Conductive film and method for manufacturing the same

Abstract

The present invention provides a conductive film, comprising a substrate and a conductive adhesive layer arranged on the substrate, wherein the conductive adhesive layer comprises a curing adhesive and a conductive slurry mixed with the curing adhesive, and the conductive adhesive layer is provided with a plurality of perforations exposing the substrate, so that the conductive adhesive layer forms a patterned structure. The present invention also provides a method for making the conductive film. The conductive film and the method for making the conductive film of the present invention not only improve the yield of the conductive film, but also make the conductive performance of the conductive film more stable.

Description

Technical Field

[0001] The present invention relates to the technical field of conductive films, and in particular to a conductive film and a manufacturing method thereof. Background Art

[0002] With the development of science and technology, more and more terminal devices with touch functions are developing towards flexibility, lightness and thinness. Transparent conductive films are widely used in the field of touch screens due to their high transmittance and good conductivity. In recent years, the demand for conductive films, which are essential for touch screens, has also increased.

[0003] In the manufacture of transparent conductive films, due to the low production efficiency of traditional metal etching processes and nanosilver laser processes, as well as the low reliability and service life of transparent conductive films, in order to solve the above problems, UV embossing is increasingly used in the manufacture of transparent conductive films. In the UV embossing method, a mold is used through a roll-to-roll embossing process to emboss a pattern groove in the UV adhesive layer (cured adhesive layer), and then the pattern groove is filled with conductive ink, and then sintered to form a conductive grid. The conductive ink is usually made of copper nano slurry or silver nano slurry. Because sintering is required after filling the conductive ink, the substrate size will shrink, making it difficult to control the size of the substrate, and ultimately leading to an increase in the defective rate of the transparent conductive film graphic size, making subsequent bonding very difficult; in addition, the inconsistency between the shrinkage rate of the substrate and the shrinkage rate of the conductive material will also cause the transparent conductive film graphic to have a short circuit. Summary of the invention

[0004] The object of the present invention is to provide a conductive film and a method for manufacturing the same, which not only improves the yield of the conductive film but also enables the conductive performance of the conductive film to be more stable.

[0005] The present invention provides a conductive film, comprising a substrate and a conductive adhesive layer arranged on the substrate, wherein the conductive adhesive layer comprises a curing adhesive and a conductive paste mixed with the curing adhesive, and the conductive adhesive layer is provided with a plurality of perforations exposing the substrate so that the conductive adhesive layer forms a patterned structure.

[0006] Furthermore, the conductive adhesive layer is a grid-shaped patterned structure.

[0007] Furthermore, the conductive paste is one or more of copper nano paste, silver nano paste, and graphene paste.

[0008] Furthermore, the width of the perforation is 4-15 μm, and the depth of the perforation is equal to the thickness of the conductive adhesive layer.

[0009] Furthermore, the thickness of the conductive adhesive layer is 3-10 μm.

[0010] Furthermore, the substrate is PET, PC or flexible glass.

[0011] The present invention also provides a method for manufacturing a conductive film, comprising:

[0012] Preparing a curing glue and a conductive paste, and mixing the curing glue and the conductive paste together;

[0013] Providing a substrate, coating the mixed curing glue and the conductive paste on the substrate to form a conductive glue layer;

[0014] A plurality of through holes exposing the substrate are made on the conductive adhesive layer to form a patterned conductive adhesive layer.

[0015] Furthermore, the step of making a plurality of through holes on the conductive adhesive layer to expose the substrate includes:

[0016] Firstly, a mold is provided, and then the mold is pressed on the conductive adhesive layer to form a plurality of grooves;

[0017] Etching is performed in the region of the conductive adhesive layer corresponding to the groove to form a plurality of through holes exposing the substrate.

[0018] Furthermore, the conductive adhesive layer is a grid-shaped patterned structure.

[0019] Furthermore, the conductive paste is one or more of copper nano paste, silver nano paste, and graphene paste.

[0020] The conductive film provided by the present invention is formed into a conductive adhesive layer by mixing a curing adhesive and a conductive slurry, and a plurality of perforations are provided on the conductive adhesive layer to expose the substrate, so that the conductive adhesive layer forms a patterned structure, which not only improves the yield of the conductive film, but also makes the conductive performance of the conductive film more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a flowchart of a method for manufacturing a conductive film according to an embodiment of the present invention;

[0022] Figure 2a to Figure 2c is a step diagram of a method for manufacturing a conductive film according to an embodiment of the present invention;

[0023] Figure 3 Schematic diagram of the structure of the conductive film in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0025] Embodiment 1

[0026] like Figures 1 to 3 As shown, the conductive film provided in the embodiment of the present invention includes a substrate 1 and a conductive adhesive layer 2 arranged on the substrate 1, the conductive adhesive layer 2 includes a curing adhesive and a conductive slurry mixed with the curing adhesive, so that the conductive adhesive layer 2 has conductivity, and a plurality of through holes 20 exposing the substrate 1 are provided on the conductive adhesive layer 2, so that the conductive adhesive layer 2 forms a patterned structure.

[0027] The substrate 1 plays a role of bearing and protection, and the light transmittance of the substrate 1 is relatively high. Specifically, the material of the substrate 1 is PET, PC or flexible glass.

[0028] In this embodiment, the conductive adhesive layer 2 is a grid-shaped patterned structure, that is, a grid-shaped conductive circuit pattern is formed.

[0029] The conductive paste uses materials with conductive properties such as copper nano paste, silver nano paste, and graphene paste.

[0030] Specifically, the width of the through hole 20 is 4-15 μm, and since the substrate 1 is exposed through the through hole 20, the depth of the through hole 20 is equal to the thickness of the conductive adhesive layer 2. The thickness of the conductive adhesive layer 2 is 3-10 μm, so it can be understood that the depth of the through hole 20 is also 3-10 μm.

[0031] In this embodiment, the conductive film is a single-layer structure. If a double-layer conductive film is required, in other embodiments, two conductive films may be subsequently bonded together to realize a double-layer conductive circuit.

[0032] like Figure 1 , Figure 2a to Figure 2c As shown, an embodiment of the present invention further provides a method for manufacturing a conductive film, which is used to manufacture the above conductive film. The method includes:

[0033] S1: preparing a curing adhesive and a conductive paste, and mixing the curing adhesive and the conductive paste together.

[0034] Specifically, the curing glue and the conductive paste are mixed in a certain ratio, or the conductive paste is filled into the curing glue, so that the mixed material has conductive properties.

[0035] S2: providing a substrate 1, and coating the mixed curing adhesive and conductive paste on the substrate 1 to form a conductive adhesive layer 2.

[0036] S3: Provide a mold 3, and then press the mold 3 onto the conductive adhesive layer 2 to form a plurality of grooves 21.

[0037] Specifically, Figure 2aAs shown, the surface of the mold 3 has a plurality of pattern grooves 31 and protrusions 32 corresponding to the pattern grooves 31. The cross-section of the pattern grooves 31 can be rectangular, trapezoidal, and irregular, with a depth of 3 to 10 μm and a width of 4 to 15 μm. The side surface of the mold 3 having the plurality of pattern grooves 31 is pressed downward toward the substrate 1 so that the protrusions 32 are imprinted on the conductive adhesive layer 2 to form a plurality of grooves 21 of the same depth corresponding to the protrusions 32, and a conductive circuit pattern corresponding to the pattern grooves 31, and then UV curing is performed. At this time, the overall thickness of the conductive adhesive layer 2 is 4 to 11 μm. The plurality of grooves 21 on the conductive adhesive layer 2 are consistent in shape with the plurality of protrusions 32. For example, the cross-section of the grooves 21 of the conductive adhesive layer 2 can be rectangular, trapezoidal, and irregular. Preferably, the mold 3 is a metal mold 3.

[0038] S4: making a plurality of through holes 20 on the conductive adhesive layer 2 to expose the substrate 1, so as to form a patterned conductive adhesive layer 2.

[0039] like Figure 2b As shown, since the protrusion 32 of the mold 3 is stamped on the conductive adhesive layer 2, residual conductive adhesive layer 2 will be left between the protrusion 32 of the mold 3 and the substrate 1, affecting the layout of the circuit, so this part of the residual conductive adhesive layer 2 needs to be removed. Specifically, as Figure 2c As shown, etching is performed in the area of ​​the conductive adhesive layer 2 corresponding to the groove 21 , and the bottom of the groove 21 is etched through to form a plurality of through holes 20 exposing the surface of the substrate 1 .

[0040] In this embodiment, the entire conductive adhesive layer 2 is etched by dry etching or wet etching process to remove 1 μm thick conductive adhesive layer 2 to form a plurality of through holes 20 exposing the substrate 1. After etching, the thickness of the conductive adhesive layer 2 is 3-10 μm.

[0041] The method for manufacturing the conductive film provided in this embodiment adopts a method of first stamping out a rough pattern of the conductive adhesive layer 2 and then performing etching to perfect it. The manufacturing steps are simple and the manufacturing cycle of the conductive film is shortened.

[0042] In other embodiments, only the remaining conductive adhesive layer 2 may be etched, that is, only the groove 21 region is etched. Specifically, a mask is used to cover the non-groove 21 region of the conductive adhesive layer 2, and then the groove 21 region is etched to remove the 1 μm thickness of the conductive adhesive layer 2 corresponding to the groove 21, so as to form a plurality of through holes 20 exposing the substrate 1.

[0043] In other embodiments, the order of S1 and S2 can be interchanged without affecting the formation of the conductive adhesive layer 2 .

[0044] In this embodiment, the conductive adhesive layer 2 is a grid-shaped patterned structure, that is, a grid-shaped conductive circuit pattern is formed.

[0045] The conductive paste uses materials with conductive properties such as copper nano paste, silver nano paste, and graphene paste.

[0046] Embodiment 2

[0047] The present embodiment provides a conductive film, including a substrate and a conductive adhesive layer arranged on the substrate, wherein the substrate has a first surface and a second surface arranged opposite to each other, the conductive adhesive layer is arranged on the first surface and the second surface respectively, the conductive adhesive layer includes a curing adhesive and a conductive slurry mixed with the curing adhesive so that the conductive adhesive layer has conductivity, and a plurality of perforations exposing the substrate are provided on the conductive adhesive layer so that the conductive adhesive layer forms a patterned structure.

[0048] Different from the first embodiment, in this embodiment, the conductive adhesive layer is disposed on the first surface and the second surface of the substrate respectively, so as to form a conductive film with a double-sided single-layer structure.

[0049] Embodiment 3

[0050] The present embodiment also provides a touch panel, which adopts the conductive layer formed by the above method. The touch panel includes a transparent glass cover plate, a first conductive adhesive layer arranged on the transparent glass cover plate, and a second conductive adhesive layer arranged on the first conductive adhesive layer, a transparent insulating support layer is arranged between the first conductive adhesive layer and the second conductive adhesive layer, and the second conductive adhesive layer is arranged on the cured transparent insulating support layer. Wherein, the first conductive adhesive layer and the second conductive adhesive layer both include a cured adhesive and a conductive slurry mixed with the cured adhesive, so that the first conductive adhesive layer and the second conductive adhesive layer have conductivity; a plurality of first perforations exposing the substrate are provided on the first conductive adhesive layer, and the transparent insulating support layer is also filled in the plurality of first perforations; a plurality of second perforations exposing the transparent insulating support layer are provided on the second conductive adhesive layer, so that the second conductive adhesive layer forms a patterned structure.

[0051] The touch panel in this embodiment directly sets the first conductive adhesive layer and the second conductive adhesive layer on the glass cover plate. Compared with the traditional GFF structure, the thickness is equivalent to reducing one substrate and two OCA optical adhesive layers. Therefore, the thickness is thinner and the light transmittance is improved. At the same time, since there is no need to set a substrate between the first conductive adhesive layer and the second conductive adhesive layer, the touch sensitivity is also improved.

[0052] In summary, in the embodiment of the present invention, the conductive adhesive layer is formed by mixing a curing adhesive and a conductive paste, and can be directly cured by ultraviolet light irradiation without the need for sintering, thereby avoiding the sintering of the conductive ink filled in the pattern groove in the prior art, which causes the substrate size to shrink and causes the conductive film defect rate to increase, and the conductive film to produce short circuit defects. The conductive film and touch panel provided by the embodiment of the present invention form a conductive adhesive layer by mixing a curing adhesive and a conductive paste, and a plurality of perforations are provided on the conductive adhesive layer to expose the substrate or the transparent insulating support layer, so that the conductive adhesive layer forms a patterned structure, which not only improves the yield of the conductive film, but also makes the conductive performance of the conductive film more stable.

[0053] In the accompanying drawings, the sizes and relative sizes of layers and regions are exaggerated for clarity. It should be understood that when an element, such as a layer, region, or substrate, is referred to as being "formed on," "disposed on," or "located on" another element, the element may be disposed directly on the other element, or there may be intervening elements. Conversely, when an element is referred to as being "formed directly on" or "disposed directly on" another element, there are no intervening elements.

[0054] In this document, the directions or positional relationships indicated by terms such as "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside", "vertical", and "horizontal" are based on the directions or positional relationships shown in the accompanying drawings and are only for the clarity of expressing the technical solutions and the convenience of description, and therefore should not be understood as limitations of the present invention.

[0055] In this document, the ordinal adjectives “first”, “second”, etc. used to describe elements are only used to distinguish elements with similar attributes, and do not mean that the elements described in this way must follow a given order, or time, space, level or other limitations.

[0056] As used herein, unless otherwise specified, “plurality” or “several” means two or more.

[0057] In this document, the terms "comprises," "comprising," or any other variations thereof, are intended to cover a non-exclusive inclusion of elements other than those listed and may also include additional elements not expressly listed.

[0058] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for manufacturing a conductive film, characterized in that: The method includes: Preparing a curing glue and a conductive paste, and mixing the curing glue and the conductive paste together; Providing a substrate, and coating the mixed curing glue and the conductive paste on the substrate to form a conductive glue layer; Making a plurality of through holes on the conductive adhesive layer to expose the substrate, so as to form a patterned conductive adhesive layer; The step of making a plurality of through holes on the conductive adhesive layer to expose the substrate comprises: Firstly, a mold is provided, and then the mold is pressed on the conductive adhesive layer to form a plurality of grooves; Etching is performed in the region of the conductive adhesive layer corresponding to the groove to form a plurality of through holes exposing the substrate.

2. The method for manufacturing a conductive film according to claim 1, wherein: The conductive adhesive layer is a grid-shaped patterned structure.

3. The method for manufacturing a conductive film according to claim 1, wherein: The conductive paste is one or more of copper nano paste, silver nano paste and graphene paste.

4. A conductive film, characterized in that: The conductive film is manufactured by the manufacturing method of any one of claims 1 to 3, comprising a substrate and a conductive adhesive layer arranged on the substrate, the conductive adhesive layer comprising a curing adhesive and a conductive slurry mixed with the curing adhesive, and the conductive adhesive layer is provided with a plurality of perforations exposing the substrate so that the conductive adhesive layer forms a patterned structure; the conductive adhesive layer is a grid-shaped patterned structure.

5. The conductive film according to claim 4, wherein: The conductive paste is one or more of copper nano paste, silver nano paste and graphene paste.

6. The conductive film according to claim 4, wherein: The width of the perforation is 4-15 μm, and the depth of the perforation is equal to the thickness of the conductive adhesive layer.

7. The conductive film according to claim 4, wherein: The thickness of the conductive adhesive layer is 3-10 μm.

8. The conductive film according to claim 4, wherein: The substrate is PET, PC or flexible glass.

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