Transparent conductive film

Abstract

The invention discloses a transparent conductive film which comprises a transparent base material layer and a conductive layer located on the surface of the transparent base material layer, and the conductive layer is obtained by coating and drying conductive liquid. The conductive liquid is prepared from the following components in parts by weight: 100 parts of a solvent, 10 to 15 parts of silver nanowires, 2 to 5 parts of polyvinyl butyral, 1 to 3 parts of polyvinylpyrrolidone, 0.1 to 0.5 part of a dispersing agent, 0.3 to 1.5 parts of a silane coupling agent, 0.1 to 1 part of a flatting agent and 0.2 to 0.6 part of polycitric acid; the diameter of the silver nanowire is 30-50 nm, and the length of the silver nanowire is 15-30 [mu] m. According to the transparent conductive film, the yellowness value of the film is reduced while the low surface resistance is maintained, and the light transmittance stability and the appearance effect of the transparent conductive film are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of conductive films, and particularly to a transparent conductive film. Background Art

[0002] As a functional film with high light transmittance and low film resistance, the transparent conductive film is widely used in fields such as touch screens, display panels, electromagnetic shielding, LED displays, electroluminescent devices, and thin-film solar cells.

[0003] Due to the disadvantages of existing transparent conductive films such as resource shortage, high price, and easy occurrence of defects, currently, those skilled in the art are committed to developing new alternative materials for use in transparent conductive films. Among them, metal nanomaterials, especially silver nanomaterials, have become the most promising alternative materials for commercialization. The existing silver nanowire transparent conductive films will turn yellow after long-term use, thus affecting their light transmittance. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a transparent conductive film, which maintains a low surface resistance while reducing the yellowness value of the film, ensuring the light transmittance stability and appearance effect of the transparent conductive film.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a transparent conductive film, comprising: a transparent substrate layer, and a conductive layer on the surface of the transparent substrate layer, the conductive layer being obtained by coating and drying a conductive liquid, and the conductive liquid being composed of the following components in parts by weight:

[0006]

[0007] The silver nanowires have a diameter of 30 - 50 nm and a length of 15 - 30 μm.

[0008] The further improved technical solutions in the above technical solutions are as follows:

[0009] 1. In the above solution, the transparent substrate layer is a PET substrate layer, a PE substrate layer, a PP substrate layer, or a PI substrate layer.

[0010] 2. In the above solution, the solvent is methanol, ethanol, or isopropanol.

[0011] 3. In the above solution, the leveling agent is isopropanol, propylene glycol monomethyl ether, diacetone alcohol, or ethylene glycol monobutyl ether.

[0012] 4. In the above solution, the dispersant is 2-amino-2-methyl-1-propanol, ethanolamine, or diethyl phthalate.

[0013] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0014] For the transparent conductive film of the present invention, the conductive layer of the transparent conductive film is based on 10-15 parts of silver nanowires, 2-5 parts of polyvinyl butyral, and 1-3 parts of polyvinylpyrrolidone and 0.2-0.6 parts of polycitric acid are added, so that while maintaining a low surface resistance, the yellowing value of the film is reduced, ensuring the light transmittance stability and appearance effect of the transparent conductive film. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Attached Figure 1 It is a schematic structural diagram of the transparent conductive film of the present invention.

[0016] In the above drawings: 1. Transparent substrate layer; 2. Conductive layer. DETAILED DESCRIPTION OF THE INVENTION

[0017] The present patent can be further clearly understood through the following specific embodiments given, but they do not limit the present patent.

[0018] The present invention will be further described below in conjunction with the embodiments:

[0019] Examples 1-4: A transparent conductive film, comprising: a transparent substrate layer 1 and a conductive layer 2 located on the surface of the transparent substrate layer 1. The conductive layer 2 is obtained by coating and drying a conductive liquid, and the conductive liquid is composed of the following components in parts by weight as shown in Table 1:

[0020] Table 1

[0021] Component Example 1 Example 2 Example 3 Example 4 Solvent 100 parts 100 parts 100 parts 100 parts Silver nanowire 12 parts 10 parts 12 parts 14 parts Polyvinyl butyral 3 parts 5 parts 3 parts 4 parts Polyvinylpyrrolidone 2 parts 1 part 2 parts 2 parts Dispersant 0.3 part 0.2 part 0.3 part 0.2 part Silane coupling agent 1 part 0.7 part 1 part 0.6 part Leveling agent 0.5 part 0.6 part 0.4 part 0.4 part Polycitric acid 0.3 part 0.2 part 0.2 part 0.3 part ;

[0022] The diameter of the above silver nanowires is 30-50 nm, and the length is 15-30 μm.

[0023] In Example 1, the transparent substrate layer is a PET substrate layer, the above solvent is methanol, the above leveling agent is propylene glycol methyl ether, and the above dispersant is diethyl phthalate.

[0024] In Example 2, the transparent substrate layer is a PP substrate layer, the above solvent is methanol, the above leveling agent is propylene glycol methyl ether, and the above dispersant is 2-amino-2-methyl-1-propanol.

[0025] In Example 3, the transparent substrate layer is a PET substrate layer, the above solvent is methanol, the above leveling agent is isopropanol, and the above dispersant is 2-amino-2-methyl-1-propanol.

[0026] In Example 4, the transparent substrate layer is a PP substrate layer, the above solvent is ethanol, the above leveling agent is ethylene glycol butyl ether, and the above dispersant is diethyl phthalate.

[0027] A preparation process for the above-mentioned transparent conductive film, comprising the following steps:

[0028] Step 1: Sequentially put silver nanowires, polyvinyl butyral, polyvinylpyrrolidone, a dispersant, a silane coupling agent, a leveling agent, and polycitric acid into a solvent, and form a uniform mixed solution through magnetic stirring. Then, let it stand for 1 to 2 hours. The diameter of the silver nanowires is 30 to 50 nm, and the length is 15 to 30 μm;

[0029] Step 2: Perform corona treatment on the transparent substrate layer by plasma;

[0030] Step 3: Coat the mixture obtained after standing on the surface of the corona-treated transparent substrate layer and dry it at 50 °C to obtain a transparent conductive film.

[0031] The drying time in the above Step 3 is 50 minutes.

[0032] Comparative Examples 1 - 3: A transparent conductive film, comprising: a transparent substrate layer 1 and a conductive layer 2 located on the surface of the transparent substrate layer 1. This conductive layer 2 is obtained by coating and drying a conductive liquid. The conductive liquid is composed of the following components in parts by weight, as shown in Table 2:

[0033] Table 2

[0034] Component Comparative Example 1 Comparative Example 2 Comparative Example 3 Solvent 100 parts 100 parts 100 parts Silver nanowire 12 parts 12 parts 12 parts Polyvinyl butyral 3 parts 3 parts 3 parts Polyvinylpyrrolidone - 2 parts - Dispersant 0.3 part 0.3 part 0.3 part Silane coupling agent 1 part 1 part 1 part Leveling agent 0.5 part 0.5 part 0.4 part Polycitric acid 0.3 part - - ;

[0035] The diameter of the above-mentioned silver nanowires is 30 to 50 nm, and the length is 15 to 30 μm.

[0036] For Comparative Examples 1 - 2, the transparent substrate layer is a PET substrate layer, the above-mentioned solvent is methanol, the above-mentioned leveling agent is propylene glycol methyl ether, and the above-mentioned dispersant is diethyl phthalate.

[0037] For Comparative Example 3, the transparent substrate layer is a PP substrate layer, the above-mentioned solvent is methanol, the above-mentioned leveling agent is propylene glycol methyl ether, and the above-mentioned dispersant is 2 - amino - 2 - methyl - 1 - propanol.

[0038] The preparation process steps of the comparative examples are the same as those of the examples.

[0039] For the transparent conductive films obtained in the above Examples 1 - 4 and Comparative Examples 1 - 3, the surface resistance of each is measured with a four - probe instrument, and the yellowness value is detected by a HunterLab colorimeter. Before detecting the yellowness value, the sample is irradiated with an ultraviolet lamp for 10 minutes. The corresponding properties are shown in Table 3:

[0040] Table 3

[0041] Sheet resistance / Ω / □ Yellowness value / B Example 1 173 1.672 Example 2 183 1.714 Example 3 182 1.753 Example 4 176 1.681 Comparative Example 1 196 1.932 Comparative Example 2 201 2.023 Comparative Example 3 192 1.911 ;

[0042] As shown in the evaluation results in Table 3, the sheet resistance of the transparent conductive films obtained in Examples 1 to 4 of the present invention is lower than 185 Ω / □, and the yellowness values are 1.672, 1.714, 1.753, and 1.681 respectively; for the transparent conductive films of Comparative Examples 1 to 3, the sheet resistance is greater than 190 Ω / □, and the yellowness values all exceed 1.9. While maintaining a low surface resistance, the transparent conductive film of this example also reduces the yellowness value of the film, ensuring the transmittance stability and appearance effect of the transparent conductive film.

[0043] The above embodiments are only used to illustrate the technical concept and features of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A transparent conductive film, characterized in that: Comprising: A transparent substrate layer (1) and a conductive layer (2) located on the surface of the transparent substrate layer (1), the conductive layer (2) is obtained by coating and drying a conductive liquid, and the conductive liquid is composed of the following components in parts by weight: 100 parts of a solvent, 10 - 15 parts of silver nanowires, 2 - 5 parts of polyvinyl butyral, 1 - 3 parts of polyvinylpyrrolidone, 0.1 - 0.5 parts of a dispersant, 0.3 - 1.5 parts of a silane coupling agent, 0.1 - 1 part of a leveling agent, 0.2 - 0.6 parts of polycitric acid; The diameter of the silver nanowires is 30 - 50 nm and the length is 15 - 30 μm.

2. The transparent conductive film according to claim 1, characterized in that: The transparent substrate layer is a PET substrate layer, a PE substrate layer, a PP substrate layer or a PI substrate layer.

3. The transparent conductive film according to claim 1, characterized in that: The solvent is methanol, ethanol or isopropanol.

4. The transparent conductive film according to claim 1, characterized in that: The leveling agent is isopropanol, propylene glycol methyl ether, diacetone alcohol or ethylene glycol butyl ether.

5. The transparent conductive film according to claim 1, characterized in that: The dispersant is 2 - amino - 2 - methyl - 1 - propanol, ethanolamine or diethyl phthalate.

Images