Transparent conductive film, touch panel, and method for manufacturing the same

Abstract

The present application relates to a kind of transparent conductive film, including the first hard coating, the first transparent conductive layer and the first metal layer formed in the first surface of substrate in turn, and the second hard coating, the second transparent conductive layer and the second metal layer of the second surface of substrate.The first hard coating and / or second hard coating contain multiple particles, to form multiple protrusions on the surface of the first metal layer and / or second metal layer, wherein, the surface arithmetic average roughness of particle is 0.025~0.5 μm.When curling transparent conductive film, multiple protrusions can form point contact between two adjacent metal layers, thereby preventing the generation of sticking.And, because the surface roughness of particle is higher, then indicate the more subtle structure of particle surface.Therefore, the contact area between particle and the first hard coating and / or second hard coating increases, so the adhesion of particle increases, thereby effectively preventing particle shedding.In addition, the present application also provides a kind of touch screen and its preparation method.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of capacitive touch screen, in particular to a transparent conductive film, a touch screen and a preparation method thereof. BACKGROUND

[0002] The transparent conductive film is a core element of the capacitive touch screen. With the rapid development of intelligent terminals, the demand for the transparent conductive film is also increasing. The transparent conductive film generally comprises a substrate and hard coating layers, conductive layers and metal layers arranged on both sides of the substrate. At present, since the amorphous polymer film has the advantages of less birefringence and uniformity compared with the crystalline polymer film, most of the transparent conductive films use the substrate formed by the amorphous polymer film.

[0003] The amorphous polymer film is more fragile than the crystalline polymer film, and its surface is more susceptible to damage. When the transparent conductive film is rolled to be in a cylindrical shape, the metal layers of adjacent transparent conductive films may be bonded and pressed to each other. Therefore, the transparent conductive film with protrusions formed on the surface of the metal layer by adding particles in the hard coating layer is provided. The protrusions can make the adjacent metal layers form point contact, thereby avoiding bonding and pressing.

[0004] However, the particles in the existing conductive film are generally spherical, and the surface thereof is relatively smooth. Therefore, the adhesion of the particles in the hard coating layer is limited. When the conductive layer and the metal layer are formed on the hard coating layer containing the particles, coating, drying and other steps are required, which will easily cause the particles with poor adhesion to fall off from the hard coating layer, thereby affecting the anti-bonding effect of the conductive film. SUMMARY

[0005] Therefore, it is necessary to provide a transparent conductive film, a touch screen and a preparation method thereof capable of effectively enhancing the adhesion of particles in view of the problem that the particles in the existing transparent conductive film with anti-bonding function are easy to fall off.

[0006] A transparent conductive film comprises:

[0007] a substrate comprising a first surface and a second surface arranged oppositely;

[0008] a first hard coating layer, a first transparent conductive layer and a first metal layer formed on the first surface in sequence;

[0009] a second hard coating layer, a second transparent conductive layer and a second metal layer formed on the second surface in sequence;

[0010] The first hard coating layer and / or the second hard coating layer contains a plurality of particles to form a plurality of protrusions on the surface of the first metal layer and / or the second metal layer, and the arithmetic average roughness of the surface of the particles is 0.025-0.5 μm.

[0011] Since the arithmetic average roughness of the surface of the particles is 0.025-0.5 μm, the roughness is high. The higher the roughness is, the more fine structures the surface of the particles has. Therefore, the contact area between the particles and the first hard coating layer and / or the second hard coating layer increases, and the adhesion of the particles is enhanced, so that the particles can be effectively prevented from falling off.

[0012] In one embodiment, the substrate is a polyalkene or polycarbonate or polyethylene terephthalate film.

[0013] The two types of films can meet the requirements for the birefringence of the substrate and its deviation, and are easy to obtain. Therefore, the cost of the transparent conductive film can be reduced.

[0014] In one embodiment, the distribution density of the protrusions is 100-3000 / mm 2 .

[0015] When the distribution density of the protrusions is too high, the haze value of the transparent conductive film is too high, and the light transmittance is reduced, which seriously affects the appearance and optical effect of the transparent conductive film. If the distribution density of the protrusions is too low, the anti-blocking effect is limited. Within the above-mentioned roughness and density ranges, the transparent conductive film can better balance the anti-blocking and optical effects.

[0016] In one embodiment, the material of the particles is the same as that of the first hard coating layer and the second hard coating layer.

[0017] That is, the optical parameters of the particles are also the same as those of the first hard coating layer and the second hard coating layer (hereinafter collectively referred to as the hard coating layer). Therefore, at the connecting interface between the particles and the hard coating layer, the light propagation is less affected, and the particles and the hard coating layer are closer to a whole. When the light passes through the hard coating layer containing the particles, the distortion of the propagation path of the light is small. Therefore, the transparent conductive film can achieve the purposes of anti-blocking and anti-crushing, and can also avoid the adverse effects on the optical performance.

[0018] In one embodiment, the material of the particles is silicon dioxide, an organic silicon polymer, an acrylic polymer or a styrene polymer.

[0019] The above materials have the advantages of good light transmittance and easy to obtain, and are used for the particles to reduce the cost under the premise of meeting the performance requirements.

[0020] In one embodiment, the height of the protrusions in the direction perpendicular to the surface of the first metal layer and / or the second metal layer is 0.1-0.5 μm.

[0021] The higher the height of the protrusions, the better the anti-sticking effect. However, as the height increases, the size of the suspended particles also needs to increase, which results in an increase in the haze value of the transparent conductive film, and after a certain degree, it will seriously affect the optical effect of the transparent conductive film. Within the above height range, the transparent conductive film can better balance the anti-sticking and optical effects.

[0022] In one embodiment, the particles are spheroids, and the size of the particles in the direction perpendicular to the surface of the substrate is greater than the size of the particles in the direction parallel to the surface of the substrate.

[0023] Conventional particles are spherical or amorphous, and the transverse (parallel to the substrate surface) and longitudinal (perpendicular to the substrate surface) sizes are comparable. Therefore, when the height of the protrusions needs to be increased, the longitudinal and transverse sizes need to be increased by the same proportion. At this time, due to the excessive transverse size, the light shielding effect caused by the particles is more obvious, resulting in an increase in the haze of the conductive film.

[0024] In the present application, the particles are spheroids, and the size of the particles in the direction perpendicular to the surface of the substrate (longitudinal) is greater than the size of the particles in the direction parallel to the surface of the substrate (transverse). That is, the long axis of the particles is perpendicular or approximately perpendicular to the surface of the substrate, and the longitudinal size is larger than the transverse size. Therefore, even if the height of the protrusions is increased, the transverse size of the particles can still be maintained within a small range, thereby improving the anti-sticking effect while effectively reducing the haze.

[0025] In one embodiment, the particles are spaced apart from the surface of the substrate, and the particle size of the particles is smaller than the thickness of the flat area of the first hard coating layer and / or the second hard coating layer, the flat area being the area of the first hard coating layer or the second hard coating layer that is not provided with the particles.

[0026] The spacing between the particles and the surface of the substrate is equivalent to suspending the particles in the first hard coating layer and / or the second hard coating layer, so the particles do not directly contact the substrate. Although the surface roughness of the particles increases, the particles do not directly contact the substrate, so the particles can prevent damage to the substrate.

[0027] In addition, in the existing anti-sticking conductive film, the particle size of the particles must be greater than the thickness of the hard coating layer, otherwise the protrusions cannot be formed on the surface of the metal layer. Therefore, the particle size is limited by the thickness of the hard coating layer and cannot be further reduced. However, the larger the particle size, the greater the haze value of the conductive film and the lower the light transmittance, which affects the optical effect of the conductive film.

[0028] In the present embodiment, the particles are suspended in the first hard coat layer and / or the second hard coat layer. Therefore, even if the particle size of the particles is smaller than the thickness of the hard coat layer, it does not affect the formation of protrusions on the surface of the first metal layer or the second metal layer. That is, the particle size of the particles is not limited by the thickness of the hard coat layer, and the particle size of the particles can be further reduced relative to the particle size of the particles in the conventional anti-adhesion conductive film, thereby reducing the haze value to improve the optical effect.

[0029] A touch screen made of the transparent conductive film according to any one of the preferred embodiments described above, the touch screen comprising a touch area and a lead area, the first metal layer and the second metal layer being located in the lead area; the touch area comprising a first electrode etched from the first transparent conductive layer and a second electrode etched from the second transparent conductive layer; the lead area comprising a first lead etched from the first metal layer and the first transparent conductive layer located in the lead area, and a second lead etched from the second metal layer and the second transparent conductive layer located in the lead area.

[0030] In the touch screen described above, the first lead and the second lead are directly etched from the first metal layer, the second metal layer, the first transparent conductive layer and the second transparent conductive layer. Therefore, there is no need to form the leads electrically connected to the first electrode and the second electrode by screen printing. Compared with the conventional touch screen, since there is no need for screen printing, the width of the electrode leads directly formed by photolithography can be further reduced, and therefore the touch screen has a narrow frame.

[0031] A method for manufacturing a touch screen, comprising the steps of:

[0032] providing a transparent conductive film according to any one of the preferred embodiments described above;

[0033] etching the first metal layer and the second metal layer to expose the first transparent conductive layer and the second transparent conductive layer of the touch area, and form a metal lead pattern located in the lead area;

[0034] etching the first transparent conductive layer and the second transparent conductive layer to form a first electrode and a second electrode located in the touch area, and form a transparent lead pattern located in the lead area, the metal lead pattern and the transparent lead pattern together constituting an electrode lead.

[0035] In the method described above, the first electrode, the second electrode and the electrode lead electrically connected to the first electrode and the second electrode can be obtained by directly etching the first metal layer, the second metal layer, the first transparent conductive layer and the second transparent conductive layer when manufacturing the touch screen. Therefore, there is no need to form the leads by screen printing, thereby effectively simplifying the process and improving the processing efficiency. Moreover, the touch screen manufactured by the method described above has a narrow frame. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 A schematic diagram of a layered structure of a transparent conductive film according to a preferred embodiment of the present application;

[0037] Figure 2 A schematic diagram of a layered structure of a transparent conductive film according to another embodiment of the present application; Figure 1 A schematic diagram of a partial A of the transparent conductive film shown;

[0038] Figure 3 A microstructure diagram of particles in the transparent conductive film shown; Figure 1

[0039] A schematic diagram of a layered structure of a transparent conductive film according to another embodiment of the present application; Figure 4

[0040] A schematic diagram of a layered structure of a touch screen according to a preferred embodiment of the present application; Figure 5

[0041] A schematic diagram of a flow of a method of manufacturing a touch screen according to a preferred embodiment of the present application. Figure 6 DETAILED DESCRIPTION

[0042] In order to facilitate the understanding of the present application, a more complete understanding of the present application can be had by reference to the following description in conjunction with the associated drawings. The preferred embodiments of the present application are illustrated in the drawings. However, the present application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the application to those skilled in the art.

[0043] It should be noted that when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present. The terms "vertical", "horizontal", "left", "right" and similar expressions as used herein are for illustration only.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0045] Reference will now be made to Figure 1 and Figure 2 ​In a preferred embodiment of the present invention, the transparent conductive film 10 includes a substrate 11, a first hard coating layer 12, a first transparent conductive layer 13, a first metal layer 14, a second hard coating layer 22, a second transparent conductive layer 23, and a second metal layer 24.

[0046] Substrate 11 includes a first surface disposed opposite to the substrate ( Figure 1 The upper surface shown) and the second surface ( Figure 1 (See lower surface shown). The first and second surfaces are merely for distinguishing the two surfaces of the substrate 11, and their positions can be interchanged. The substrate 11 is formed of an amorphous polymer film. Since the amorphous polymer film has a smaller and more uniform birefringence than the crystalline polymer film, color inhomogeneity in the transparent conductive film 10 of the present invention can be eliminated. The in-plane birefringence of the amorphous polymer film used in the present invention is preferably 0 to 0.001, more preferably 0 to 0.0005. The deviation of the in-plane birefringence of the amorphous polymer film used in the present invention is preferably 0.0005 or less, more preferably 0.0003 or less.

[0047] The aforementioned birefringence and its deviation can be achieved by selecting a suitable type of amorphous polymer film. Specifically, in this embodiment, the substrate 11 is a polycyclic olefin, polycarbonate, or polyethylene terephthalate film. These two types of films can meet the requirements for birefringence and its deviation. The thickness of the substrate 11 formed from the amorphous polymer film is 20 μm to 200 μm.

[0048] A first hard coating layer 12, a first transparent conductive layer 13, and a first metal layer 14 are sequentially formed on the first surface of the substrate 11. A second hard coating layer 22, a second transparent conductive layer 23, and a second metal layer 24 are sequentially formed on the second surface of the substrate 11. Wherein:

[0049] The first hard coating 12 protects the first surface of the substrate 11. The first hard coating 12 comprises an adhesive resin. This adhesive resin comprises, for example, a curable resin composition based on ultraviolet light or electron beams. The curable resin composition preferably comprises a polymer obtained by the addition reaction of a glycidyl acrylate polymer with acrylic acid. Alternatively, the curable resin composition preferably comprises a polyfunctional acrylate polymer (pentaerythritol, dipentaerythritol, etc.). The curable resin composition also comprises a polymerization initiator.

[0050] A first transparent conductive layer 13 is formed on the surface of the first hard coating layer 12. The first transparent conductive layer 13 has high transmittance (over 80%) in the visible light region (380nm to 780nm) and a surface resistivity per unit area (unit: Ω / m). 2 ) is 500Ω / m 2The following layers are formed. The thickness of the first transparent conductive layer 13 is preferably 15 nm to 100 nm, more preferably 15 nm to 50 nm. The first transparent conductive layer 13 is formed of, for example, any one of indium tin oxide (ITO), indium tin oxide, or an indium oxide-zinc oxide composite.

[0051] The first metal layer 14 is formed on the surface of the first transparent conductive layer 13. The first metal layer 14 is used to form a wiring on the outside of a touch input area when the transparent conductive film of the present application is used in, for example, a touch panel. As the material for forming the first metal layer 15, copper, silver, and any other metal having excellent conductivity are representative. The thickness of the first metal layer 14 is preferably 50 nm to 500 nm, more preferably 100 nm to 300 nm.

[0052] Further, the second hard coat layer 22, the second transparent conductive layer 23, and the second metal layer 24 have the same film layer structure, function, and material composition as the first hard coat layer 12, the first transparent conductive layer 13, and the first metal layer 14, respectively, and thus will not be described again here.

[0053] In addition, the first hard coat layer 12 and / or the second hard coat layer 22 contain a plurality of particles 15 to form a plurality of protrusions 16 on the surface of the first metal layer 14 and / or the second metal layer 24. Please refer to Figure 3 The surface of the particles 15 is a non-smooth surface. The arithmetic average roughness of the surface of the particles 15 is 0.025 to 0.5 μm. Thus, the roughness of the surface of the particles 15 is higher, indicating that there are more fine structures on the surface of the particles 15. The fine structures can be fine concave-convex, undulations, and the like on the surface of the particles 15.

[0054] Specifically, the particles 15 can be distributed irregularly or in a predetermined pattern (e.g., uniformly) in the first hard coat layer 12 and / or the second hard coat layer 22. The shape of the particles 15 can be spherical, ellipsoidal, or the like. The particles 15 can be contained only in the first hard coat layer 12 or the second hard coat layer 12, thereby obtaining a transparent conductive film 10 having protrusions 16 formed on one side; or the particles 15 can be contained in both the first hard coat layer 12 and the second hard coat layer 12, thereby obtaining a transparent conductive film 10 having protrusions 16 formed on both sides.

[0055] The following describes the formation of the protrusions 16 on the surface of the first metal layer 14:

[0056] The particles 15 protrude from the surface of the first hard coat layer 12, so that the surface of the first hard coat layer 12 forms a convex region, and the region of the first hard coat layer 12 where no particles 15 are present forms a flat region 17. Since the first transparent conductive layer 13 and the first metal layer 14 are sequentially stacked on the surface of the first hard coat layer 12, the surface shapes of the first transparent conductive layer 13 and the first metal layer 14 are the same as the surface shape of the first hard coat layer 12. Therefore, in the region of the first metal layer 14 corresponding to the particles 14, a plurality of protrusions 16 are formed.

[0057] Similarly, when the second hard coat layer 22 contains the particles 15, the surface of the second metal layer 24 can also form a plurality of protrusions 16.

[0058] When the transparent conductive film 10 is manufactured by a roll to roll process, the particles 15 cause the surface of the first metal layer 14 and / or the second metal layer 24 to form a plurality of protrusions 16. Therefore, when the transparent conductive film 10 is rolled, the plurality of protrusions 16 can cause the adjacent two metal layers to form point contacts, thereby preventing mutual adhesion and pressure bonding.

[0059] Furthermore, since the surface arithmetic mean roughness of the particles 15 is high, the contact area between the particles 15 and the first hard coat layer 12 and / or the second hard coat layer 22 increases, so that the adhesion of the particles 15 increases, thereby effectively preventing the particles 15 from falling off.

[0060] In the present embodiment, the first hard coat layer 12 and the second hard coat layer 22 both contain the particles 15, so that the surface of the first metal layer 14 and the surface of the second metal layer 24 both form a plurality of protrusions 16.

[0061] That is, the obtained transparent conductive film 10 has a plurality of protrusions 16 on both sides. Therefore, when the transparent conductive film 10 is rolled, the number of point contacts between the adjacent two metal layers increases, so that the effect of preventing adhesion and pressure bonding is better.

[0062] Please refer to Figure 4 In another embodiment, either the first hard coat layer 12 or the second hard coat layer 22 contains the particles 15, so that the surface of the first metal layer 14 or the surface of the second metal layer 24 forms a plurality of protrusions 16.

[0063] That is, the obtained transparent conductive film 10 has a plurality of protrusions 16 on only one side. Therefore, the mutual superposition of the shadows of the two layers of particles 15 can be avoided, so that the haze is reduced, thereby improving the optical effect of the transparent conductive film 10.

[0064] In the present embodiment, the particles 15 and the first hard coat layer 12 and the second hard coat layer 22 are made of the same material.

[0065] Since the material of the particles 15 is the same as that of the first hard coating layer 12 and the second hard coating layer 22 (hereinafter collectively referred to as the hard coating layer), the optical parameters of the particles 15 are also the same. Therefore, at the connecting interface between the particles 15 and the hard coating layer, the light propagation is less affected, and the particles 15 and the hard coating layer are closer to a whole. When the light passes through the hard coating layer containing the particles 15, the distortion of the light propagation path is smaller. Therefore, the transparent conductive thin film 10 can achieve the purpose of anti-adhesion and anti-pressing while avoiding the adverse effect on the optical performance.

[0066] Further, in the present embodiment, the material of the particles 15 is silicon dioxide, organic silicon polymer, acrylic polymer or styrene polymer.

[0067] The above materials have the advantages of good light transmission and easy to obtain, and can be used for the particles 15 to reduce the cost under the premise of meeting the performance requirements. Of course, other suitable materials can also be selected according to the actual performance and cost requirements.

[0068] In the present embodiment, the particles 15 are ellipsoidal, and the size of the particles 15 in the direction perpendicular to the surface of the substrate 11 is greater than that in the direction parallel to the surface of the substrate.

[0069] The conventional particles are spherical or amorphous, and the transverse (parallel to the surface of the substrate) and longitudinal (perpendicular to the surface of the substrate) sizes are comparable. Therefore, when the height of the protrusion 16 needs to be increased, the longitudinal and transverse sizes of the particles 15 also need to be increased in proportion. However, when the transverse size of the particles 15 is too large, the light shielding effect caused by the particles 15 is more obvious, thereby increasing the haze of the conductive film.

[0070] In the present embodiment, the particles 15 are ellipsoidal, and the size of the particles 15 in the direction perpendicular to the surface of the substrate 11 (longitudinal direction) is greater than that in the direction parallel to the surface of the substrate 11 (transverse direction). That is, the long axis of the particles 15 is arranged perpendicular or approximately perpendicular to the surface of the substrate 11, and the longitudinal size is larger than the transverse size. Therefore, even if the height of the protrusion 16 is increased, the transverse size of the particles 15 can still be maintained within a small range, thereby improving the anti-adhesion effect of the transparent conductive thin film 10 while effectively reducing the haze.

[0071] In the present embodiment, the particles 15 are spaced apart from the surface of the substrate 11, and the particle size of the particles 15 is smaller than the thickness of the flat area 17 of the first hard coating layer 12 and / or the second hard coating layer 22.

[0072] Specifically, the particles 15 are spaced apart from the surface of the substrate 11, which is equivalent to suspending the particles 15 in the first hard coating layer 12 and / or the second hard coating layer 22, so that the particles 15 are not in direct contact with the substrate 11. Although the surface roughness of the particles 11 is increased, the particles 15 can prevent the damage to the substrate 11 because they are not in direct contact with the substrate 11.

[0073] In addition, in the existing anti-adhesion conductive film, the particle size of the particles must be greater than the thickness of the hard coat layer, otherwise the particles cannot form protrusions on the surface of the metal layer. Therefore, the particle size is limited by the thickness of the hard coat layer, and cannot be further reduced. However, the larger the particle size, the greater the haze value of the conductive film, the lower the light transmittance, and the greater the impact on the optical effect of the conductive film.

[0074] In the present embodiment, the particles 15 are suspended in the first hard coat layer 12 and / or the second hard coat layer 22. Therefore, even if the particle size of the particles 15 is smaller than the thickness of the hard coat layer, it does not affect the formation of protrusions on the surface of the first metal layer 14 or the second metal layer 24. That is, the particle size of the particles 15 is not limited by the thickness of the hard coat layer, and the particle size of the particles 15 can be further reduced compared to the particle size of the particles in the existing anti-adhesion conductive film, thereby reducing the haze value to improve the optical effect.

[0075] In order to achieve better anti-adhesion and anti-crushing effect, the surface roughness of the first metal layer 14 and the second metal layer 24 and the density of the protrusions 16 have corresponding requirements.

[0076] In the present embodiment, the arithmetic average roughness Ra of the surface of the first metal layer 14 and the second metal layer 24 is 0.0025-0.025 μm. In addition, the distribution density of the protrusions 16 on the surface of the first metal layer 14 is 100-3000 / mm 2 .

[0077] When the distribution density of the protrusions 16 is too large, it will cause the haze value of the transparent conductive film 10 to be too large, the light transmittance to be reduced, and the appearance and optical effect of the transparent conductive film 10 to be seriously affected. If the distribution density of the protrusions 16 is too small, the anti-adhesion effect is limited. Within the above roughness and density range, the transparent conductive film 10 can better balance the anti-adhesion and optical effect.

[0078] The arithmetic average roughness Ra and the distribution density of the surface of the first metal layer 14 and the second metal layer 24 can be changed by adjusting the shape, size and content of the particles 15.

[0079] Further, in the present embodiment, the height of the plurality of protrusions 16 in the direction perpendicular to the surface of the first metal layer 14 and / or the second metal layer 24 is 0.1-0.5 μm.

[0080] The height of the protrusion 16 refers to the height of the protrusion 16 protruding from the surface of the first metal layer 14 and / or the second metal layer 24. Since the size of the particle 15 is small, it is difficult to precisely control the height of each protrusion 16. Therefore, the height of the protrusion 16 is controlled within the above range. It should be noted that in actual production, due to the difficulty in precisely controlling each particle 15, it is inevitable that a small portion of the particles 15 form protrusions 16 with heights outside the above range. However, the influence of the protrusions 16 is negligible.

[0081] In general, the higher the height of the protrusion 16, the better the anti-sticking effect. However, as the height increases, the size of the particle 15 needs to increase accordingly, which leads to an increase in the haze value of the transparent conductive film 10, and after a certain degree, it will seriously affect the optical effect of the transparent conductive film 10. Within the above height range, the transparent conductive film 10 can better balance the anti-sticking and optical effects. The height of the protrusion 16 can be changed by adjusting the size of the particle 15.

[0082] The transparent conductive film 10 described above, the particle 15 forms a plurality of protrusions 16 on the surface of the first metal layer 14 and / or the second metal layer 24. Therefore, when the transparent conductive film 10 is rolled, the plurality of protrusions 16 can form point contact between adjacent two metal layers to prevent sticking. Moreover, the arithmetic mean roughness of the surface of the particle 16 is 0.025-0.5 μm, which has a high roughness. The higher the roughness, the more fine structures on the surface of the particle 15. Therefore, the contact area between the particle 15 and the first hard coating layer 12 and / or the second hard coating layer 22 increases, so the adhesion of the particle 15 increases, thereby effectively preventing the particle 15 from falling off.

[0083] In addition, the present application also provides a touch screen. Please refer to Figure 5 The touch screen 200 in the preferred embodiment of the present application is made of the transparent conductive film 10 in the above embodiment. Wherein:

[0084] The touch screen 200 includes a touch area 210 and a lead area 220. Specifically, the touch area 210 is located in the middle of the touch screen 200, and the lead area 220 is arranged around the circumference of the touch area 210. The first metal layer 14 and the second metal layer 24 are located in the lead area 220.

[0085] The touch area 210 includes a first electrode 211 and a second electrode 212. The first electrode 211 is etched from the first transparent conductive layer 13, and the second electrode 212 is etched from the second transparent conductive layer 23. The first electrode 211 and the second electrode 212 are etched into an electrode pattern. Specifically, the electrode pattern is generally in the shape of a long strip and vertically intersects to form a grid shape, and the opposite first electrode 211 and second electrode 212 form two poles of a capacitive structure.

[0086] The lead area 220 includes a first lead 221 and a second lead 222. The first lead 221 is etched from the first metal layer 14 and the first transparent conductive layer 13 located in the lead area 220, and the second lead 222 is etched from the second metal layer 24 and the second transparent conductive layer 23 located in the lead area 220. The first lead 221 and the second lead 222 are double-layer structures, thereby realizing electrical connection with the first electrode 211 and the second electrode 212.

[0087] In the above touch screen, the first lead 221 and the second lead 222 are directly etched from the first metal layer 14, the second metal layer 24, the first transparent conductive layer 13, and the second transparent conductive layer 23. Therefore, the width of the electrode lead directly formed by the lithography process can be further reduced without screen printing, and thus the touch screen has a narrow frame.

[0088] Please refer to Figure 6 The application further provides a preparation method of the touch screen, which includes steps S310-S330.

[0089] Step S310: providing a transparent conductive film.

[0090] Specifically, the transparent conductive film is the transparent conductive film 100 in the above embodiment, which includes the first transparent conductive layer 13 and the first metal layer 14 arranged in layers, and the second transparent conductive layer 23 and the second metal layer 24 arranged in layers.

[0091] Step S320: etching the first metal layer 14 and the second metal layer 24 to expose the first transparent conductive layer 13 and the second transparent conductive layer 23 of the touch area, and form a metal lead pattern located in the lead area.

[0092] Specifically, the metal lead pattern can be formed on the surface of the metal layer by one lithography process. The metal lead pattern is arranged along the edge of the touch screen. After etching the metal layer, the first transparent conductive layer 13 and the second transparent conductive layer 24 in the lower layer are partially exposed.

[0093] Step S330, etching the first transparent conductive layer 13 and the second transparent conductive layer 23 to form the first electrode 211 and the second electrode 212 located in the touch area, and form the transparent lead pattern located in the lead area, the metal lead pattern and the transparent lead pattern jointly constitute the electrode lead.

[0094] Specifically, the exposed part of the first transparent conductive layer 13 and the second transparent conductive layer 24 is etched by another photolithography process to form the electrode pattern, so that the first electrode 211 and the second electrode 212 can be obtained. At the same time, the first metal layer 14 and the second metal layer 24 in the form of metal lead pattern are respectively superimposed with the first transparent conductive layer 13 and the second transparent conductive layer 23 in the lead area, thereby forming the first lead 221 and the second lead 222 in double-layer structure. The first lead 221 and the second lead 222 are respectively electrically connected with the first electrode 211 and the second electrode 212.

[0095] By using the above method in the preparation of the touch screen, the first metal layer 14, the second metal layer 24, the first transparent conductive layer 13 and the second transparent conductive layer 23 are etched directly, so that the first electrode 211, the second electrode 212 and the first lead 221 and the second lead 222 electrically connected with the first electrode 211 and the second electrode 212 can be obtained. Therefore, it is not necessary to form the lead by using the silk printing method, thereby effectively simplifying the process and improving the processing efficiency. Moreover, the touch screen prepared by the above method has a narrow frame.

[0096] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, however, as long as the combinations of the technical features do not exist contradictions, they should be considered as the scope of the present disclosure.

[0097] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the scope of protection of the present application should be subject to the appended claims.

Claims

1. A transparent conductive film, comprising: a substrate comprising a first surface and a second surface disposed opposite to each other, the substrate having an in-plane birefringence of 0 to 0.001; a first hard coat layer, a first transparent conductive layer, and a first metal layer sequentially formed on the first surface; a second hard coat layer, a second transparent conductive layer, and a second metal layer sequentially formed on the second surface; wherein the first hard coat layer and / or the second hard coat layer comprises a plurality of particles to form a plurality of protrusions on a surface of the first metal layer and / or the second metal layer, the particles having a surface arithmetic mean roughness of 0.025 to 0.5 μm; the particles are ellipsoidal, and a dimension of the particles in a direction perpendicular to the surface of the substrate is greater than a dimension of the particles in a direction parallel to the surface of the substrate. The substrate is a polynorbornene or polycarbonate or polyethylene terephthalate film. The particles are made of the same material as the first hard coat layer and the second hard coat layer. The particles are made of silica, silicone polymer, acrylic polymer, or styrene polymer. The particles are spaced apart from the surface of the substrate, and a particle size of the particles is less than a thickness of a flat area of the first hard coat layer and / or the second hard coat layer, the flat area being an area of the first hard coat layer or the second hard coat layer where the particles are not disposed. The touch screen is made of the transparent conductive film according to any one of claims 1 to 7, the touch screen comprising a touch area and a lead area, the first metal layer and the second metal layer being located in the lead area; the touch area comprising a first electrode etched from the first transparent conductive layer and a second electrode etched from the second transparent conductive layer; the lead area comprising a first lead etched from the first metal layer and the first transparent conductive layer located in the lead area, and a second lead etched from the second metal layer and the second transparent conductive layer located in the lead area.

2. The transparent conductive film according to claim 1, wherein The method comprises the steps of: providing a transparent conductive film according to any one of claims 1 to 7; etching the first metal layer and the second metal layer to expose the first transparent conductive layer and the second transparent conductive layer of the touch area, and to form a metal lead pattern located in the lead area; etching the first transparent conductive layer and the second transparent conductive layer to form a first electrode and a second electrode located in the touch area, and to form a transparent lead pattern located in the lead area, the metal lead pattern and the transparent lead pattern together constituting an electrode lead.

3. The transparent conductive film according to claim 1, wherein The distribution density of the protrusions is 100-3000 / mm 2 .

4. The transparent conductive film according to claim 1, wherein ​ 5. The transparent conductive film according to claim 4, wherein ​ 6. The transparent conductive film according to claim 1, wherein ​ 7. The transparent conductive film according to any one of claims 1 to 6, wherein ​ 8. A touch screen, characterized by ​ 9. A method for manufacturing a touch screen, characterized by, ​ ​ ​ ​

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