Composite conductive film

Abstract

The utility model discloses a composite conductive film, which comprises a base film and a conductive layer, the base film comprises a first base film, the first base film is provided with a through first anchoring hole, at least one surface of the first base film is connected with a second base film, one side of the second base film close to the first base film is embedded into the anchoring hole to form a first anchoring point, and the first anchoring point is connected with the conductive layer. The conductive layer is compounded on the surface layer, away from the first base film, of the second base film, and the conductive layer and the second anchoring hole act to form a second anchoring point. The composite film is provided with a composite base film structure, meanwhile, anchoring structures are formed between the base films, the composite film is formed, the performance of the base films can be improved, and application scenes are increased.

Description

Technical Field

[0001] The utility model relates to the technical field of conductive film materials, in particular to a composite conductive film. Background Art

[0002] The composite conductive film is a polymer material with a metal plated on the surface. It can be used in the field of secondary batteries as a current collector, or in the field of optoelectronics as a (flexible) conductive film. For example, aluminum film is generally obtained based on evaporation, and composite copper film is obtained by water electroplating after forming a copper seed layer.

[0003] For composite copper film, the commonly used method in the industry is secondary plating; the base film materials of composite copper film commonly used in the industry are PET, PP and PI. PI is too expensive, and PET is not resistant to acid and alkali corrosion, which limits its use in certain scenarios; PP has relatively poor mechanical properties.

[0004] Further improvements are needed. Utility Model Content

[0005] The utility model aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one purpose of the utility model is to provide a composite conductive film having a composite base film structure, and at the same time, an anchoring structure is formed between the base films to form a composite film, which can improve the performance of the base film and increase the applicable scenarios.

[0006] The technical solution of the utility model is as follows:

[0007] A composite conductive film comprises a base film and a conductive layer, wherein the base film comprises a first base film, a first through anchoring hole is arranged on the first base film, and a second base film is connected to at least one surface of the first base film, a side of the second base film close to the first base film is embedded in the anchoring hole to form a first anchoring point, and a second anchoring hole is formed on the surface of the second base film corresponding to the first anchoring point, and the conductive layer is composited on the surface of the second base film away from the first base film, and acts with the second anchoring hole to form a second anchoring point.

[0008] Based on the above technical solution, the bonding force between the composite base films can be improved, and the roughness of the base film surface can be further improved to enhance the adhesion of the subsequent conductive layer.

[0009] Furthermore, a second base film is formed on one surface in the thickness direction of the first base film.

[0010] Further, the thickness of the first base film is D, the thickness of the second base film is D1, and D1≥0.6D is satisfied.

[0011] Further, the thickness of the first base film is D, and the thickness of the second base film is D1, satisfying D1≥D.

[0012] Furthermore, the second base film is formed on two surfaces in the thickness direction of the first base film, and the second base film on both sides forms a first anchoring point in the first anchoring hole.

[0013] Based on the above technical solution, the second basement membrane is provided on both sides, which can reduce the thickness of the second basement membrane and further reduce the influence of the thickness of the first basement membrane on the depth of the second anchoring hole, and also reduce the thickness of the second basement membrane to a certain extent.

[0014] Further, when the thickness of the first base film is D, the thickness of the second base film is D1, and D1≥0.5D is satisfied, the formed first anchoring points contact and interact with each other to form a connecting portion.

[0015] Based on the above technical solution, the mutual anchoring force between the two second basement membranes is further increased, thereby improving the overall consistency of the basement membrane and preventing it from delaminating.

[0016] Furthermore, the diameter of the first anchoring hole is 0.05-1 mm, and the hole spacing is 0.5-10 mm.

[0017] Furthermore, the thickness D of the first base film is 2-12 μm.

[0018] Furthermore, the thickness D of the first base film is 3-6 μm.

[0019] Furthermore, the first base film material is a polyester film, and / or the second base film material is a polyolefin film.

[0020] Furthermore, the first base film material is polyethylene terephthalate (PET), and the second base film material is polypropylene (PP).

[0021] Based on the above technical solution, that is, selecting PET (polyester) as the first base film and selecting PP (polyolefin) as the second base film, the processing performance of PP can be improved. At the same time, the surface corrosion resistance is enhanced, and the setting of anchor points can also improve the connection strength between the two.

[0022] Furthermore, the conductive layer is a metal layer or a conductive coating.

[0023] Compared with the prior art, the utility model has the following beneficial effects: by setting a first anchoring hole and allowing the two groups of base films to form an anchoring effect through the anchoring hole, the adhesion between the base films can be improved, which is especially suitable for films with poor compatibility; the base film structure formed based on thermal composite also increases the vacancy defects on the surface of the base film to a certain extent, thereby increasing the bonding strength with the conductive layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a conductive film having a metal layer formed on one side;

[0025] Figure 2A schematic diagram of a conductive film having a metal layer formed on both sides;

[0026] Figure 3 for Figure 1 Schematic diagram of single-sided processing;

[0027] Figure 4 for Figure 2 Schematic diagram of double-sided processing.

[0028] In the figure: 1-first basement membrane; 11-first anchoring hole; 2-conductive layer; 21-second anchoring point; 3-second basement membrane; 31-first anchoring point; 32-second anchoring hole; 33-connecting part; 4-first hot pressing roller; 5-first cooling roller; 6-second hot pressing roller; 7-second cooling roller. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the contents in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0030] Reference Figure 1 A composite conductive film comprises a base film and a conductive layer 2, wherein the base film comprises a first base film 1, a first through anchoring hole 11 is arranged on the first base film 1, and a second base film 3 is connected to the surface of the first base film, and the second base film 3 is embedded in the anchoring hole 11 on the side close to the first base film 1 to form a first anchoring point 31, and the second base film 3 forms a second anchoring hole 32 on its surface corresponding to the first anchoring point 31, and the conductive layer 2 is composited on the surface of the second base film 3 (away from the first base film 1), and acts with the second anchoring hole 32 to form a second anchoring point 21.

[0031] In this embodiment, only a single conductive layer 2 is shown.

[0032] The first anchoring hole 11 can be formed by physical opening, such as by rolling with a needle roller, and the hole diameter can be adaptively selected according to the actual situation. The hole diameter is preferably 0.05-1mm, and the hole distance is 0.5-10mm;

[0033] The first base film 1 and the second base film 3 are connected by heat pressing and further referring to Figure 3 During compounding, the second base film 3 is attached to the first hot pressing roller 4, and the temperature is raised to near Tg (glass transition temperature) or near the softening temperature to soften the material, and then embedded in the first anchoring hole 11 after rolling. The rolling pressure is set in combination with the film thickness setting, and then it is immediately cooled to the glass transition temperature range (or the crystalline state, a temperature range that is not easily deformed) by the first cooling roller 5. After rolling and cooling, the first anchoring point 31 is formed. Due to the formation of the first anchoring point 31, the corresponding part of the top of the second base film 3 will be concave (the concave radius is larger and the depth is smaller), forming a second anchoring hole 32.

[0034] The thickness D of the first base film is controlled to be 2-12 μm, preferably 3-6 μm, and D1 is controlled to be D1≥0.6D, preferably D1≥D.

[0035] The materials of the first base film 1 and the second base film 2 can be selected according to their adaptability, such as polyamide, polyterephthalate, polyimide, polyethylene, polypropylene, polystyrene, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer, polybutylene terephthalate, poly(p-phenylene terephthalamide), polypropylene, polyoxymethylene, polytetrafluoroethylene or polycarbonate, etc.; when used as a conductive film, PP and PET are commonly used as base films in the industry, and in the present application, the two are preferably composited, that is, PET (polyester) is selected as the first base film, and PP (polyolefin) is selected as the second base film, which can improve the processing performance of PP. At the same time, the surface corrosion resistance is improved, and the setting of anchor points can also improve the connection strength between the two.

[0036] The conductive layer 2 can be a metal layer, which is obtained by physical deposition or two-step method (physical deposition followed by water electroplating); the conductive layer can also be obtained by coating a conductive slurry. The thickness of the conductive layer is not limited here, and is preferably 0.3-3 μm.

[0037] Reference Figure 2 , the figure shows a situation where the second basement membrane 3 is arranged on both surfaces of the first basement membrane 1. At this time, the second basement membranes 3 on both sides form first anchoring points 31 in the first anchoring holes 11, and when D1 ≥ 0.5D (preferably greater than or equal to 0.8D), the first anchoring points 31 can contact and interact with each other to form a connecting portion 33, further increasing the force of the two second basement membranes 3.

[0038] The second basement membrane 3 is provided on both sides, which can further reduce the influence of the thickness of the first basement membrane 1 on the second anchoring hole 32 and also reduce the thickness of the second basement membrane.

[0039] like Figure 4 During processing, hot rolling and cooling can be carried out twice, and the number of related roller groups can be adaptively selected.

[0040] Alternatively, thermal compounding (not shown in the figure) may be performed once, followed by cooling to obtain a base film, and then a conductive layer may be further provided to obtain a conductive film.

[0041] The composite conductive film can be used as a current collector for battery electrodes, an electromagnetic shielding film or as a conductive flexible film in the optoelectronic field.

[0042] In this application, structures and connection relationships that are not described in detail are all prior arts, and their structures and principles are well-known technologies and will not be described in detail here.

[0043] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0044] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A composite conductive film, comprising a base film and a conductive layer, characterized in that: The base film includes a first base film, a first anchoring hole is set on the first base film, and a second base film is connected to at least one surface of the first base film, the second base film is embedded in the anchoring hole on one side close to the first base film to form a first anchoring point, and the second base film forms a second anchoring hole on its surface corresponding to the first anchoring point, and the conductive layer is compounded on the surface of the second base film away from the first base film, and acts with the second anchoring hole to form a second anchoring point.

2. The composite conductive film according to claim 1, characterized in that: A second base film is formed on one surface of the first base film in a thickness direction.

3. The composite conductive film according to claim 2, characterized in that: The thickness of the first base film is D, the thickness of the second base film is D1, and D1≥0.6D is satisfied.

4. The composite conductive film according to claim 3, characterized in that: The thickness of the first base film is D, and the thickness of the second base film is D1, satisfying D1≥D.

5. The composite conductive film according to claim 1, characterized in that: The second base film is formed on two surfaces in the thickness direction of the first base film, and the second base film on both sides forms a first anchoring point in the first anchoring hole.

6. The composite conductive film according to claim 5, characterized in that: The thickness of the first base film is D, the thickness of the second base film is D1, and when D1≥0.5D is satisfied, the formed first anchor points contact and interact with each other to form a connection portion.

7. The composite conductive film according to any one of claims 1 to 6, characterized in that: The diameter of the first anchoring hole is 0.05-1 mm, and the hole spacing is 0.5-10 mm.

8. The composite conductive film according to claim 7, characterized in that: The thickness D of the first base film is 2-12 μm.

9. The composite conductive film according to claim 7, characterized in that: The first base film material is a polyester film, and / or the second base film material is a polyolefin film.

10. The composite conductive film according to claim 9, characterized in that: The first base film material is polyethylene terephthalate (PET), and the second base film material is polypropylene (PP).

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