An electrochromic film

Abstract

This invention provides an electrochromic film comprising a lower substrate, a lower circuit layer, an electrolyte layer, an upper circuit layer, and an upper substrate stacked sequentially. Multiple patterned grid grooves are formed on both the lower and upper circuit layers, and these grooves are filled with conductive material. The patterned grid grooves are located on the lower circuit layer and on the upper circuit layer, respectively, on the side away from the lower substrate. The lower and upper circuit layers form an electric field under the voltage of an external power supply, causing the electrolyte layer to change in brightness. Combining the circuit layer with the patterned grid grooves with the electrolyte layer overcomes the shortcomings of existing technologies using ITO material, resulting in high transmittance, low sheet resistance, and bend resistance. This enables rapid dimming and reduces manufacturing costs. Furthermore, it solves the problem of interference fringes during application, resulting in more uniform dimming and meeting the needs of multiple fields.

Description

Technical Field

[0001] This utility model relates to the field of optoelectronic technology, and in particular to an electrochromic film. Background Technology

[0002] In existing technologies, conventional glass materials and automotive sunroof structures generally suffer from insufficient sunlight-blocking performance. When exposed to direct sunlight, their optical adjustment capabilities are limited, forcing users to rely on external sunshade devices (such as curtains or sun visors) to achieve a shading effect. This passive shading solution suffers from technical problems such as poor ease of operation and aesthetic impact.

[0003] Current dimming films primarily utilize indium tin oxide (ITO) conductive materials. However, ITO materials suffer from several limitations: slow electrochromic response, with typical response times exceeding industry application requirements; low optical transmittance, generally below 85% in the visible light region; high sheet resistance, affecting dimming uniformity; brittle mechanical properties leading to cracking and difficulty in adapting to flexible devices (such as foldable screens and curved smart windows), with conductivity drastically decreasing under repeated bending or impact; and high material and manufacturing costs, limiting large-area applications (such as architectural glass). Given the demands for flexibility, low cost, and large-area applications, the development of alternative materials has become a key breakthrough in this field. Therefore, there is an urgent need for a thin film that is both conductive and possesses high transparency in the visible light range, low sheet resistance, and reduced manufacturing costs, making it suitable for various industry needs. Utility Model Content

[0004] In view of this, the purpose of this utility model is to provide an electrochromic film with high transmittance, low sheet resistance, bend resistance and reduced manufacturing cost, which can achieve rapid dimming.

[0005] This invention provides an electrochromic film comprising a lower substrate, a lower circuit layer, an electrolyte layer, an upper circuit layer, and an upper substrate stacked sequentially. Multiple patterned grid grooves are provided on both the lower and upper circuit layers. The patterned grid grooves are filled with conductive material. The patterned grid grooves are located on the lower circuit layer and on the upper circuit layer, respectively, on the side away from the lower substrate. The lower and upper circuit layers are used to form an electric field under the voltage of an external power supply, causing the electrolyte layer to change between light and dark.

[0006] Furthermore, the width and depth of the graphical mesh grooves range from 1μm to 50μm.

[0007] Furthermore, the spacing between two adjacent patterned grid grooves ranges from 100μm to 1000μm.

[0008] Furthermore, the thickness of the lower circuit layer and the upper circuit layer ranges from 10μm to 70μm. The depth of the patterned mesh groove on the lower circuit layer is less than the thickness of the lower circuit layer, and the depth of the patterned mesh groove on the upper circuit layer is less than the thickness of the upper circuit layer.

[0009] Furthermore, the transmittance of the lower circuit layer and the upper circuit layer is ≥85%.

[0010] Furthermore, the sheet resistance range of the lower and upper circuit layers is 0.2Ω / □ to 10Ω / □.

[0011] Furthermore, the top view shape of the graphical grid groove is a quadrilateral, hexagon, regular polygon, sine, or irregular polygon.

[0012] Furthermore, the top view shape of the graphical mesh groove is a sinusoidal mesh with a period ranging from 100µm to 500µm.

[0013] Furthermore, the edges of the sinusoidal grid are sinusoidal curves, and the difference between the peaks and troughs of the sinusoidal curves ranges from 20µm to 100µm.

[0014] Furthermore, the ratio of the difference between the peaks and troughs of the sinusoidal curve to the period of the sinusoidal grid ranges from 1 / 25 to 1 / 2.

[0015] Compared with existing color-changing films using ITO materials, the electrochromic film provided by this invention has the following advantages:

[0016] (1) By combining the circuit layer with the electrolyte layer of the patterned grid groove with conductive material, the defects of the existing technology using ITO material are overcome. It has the characteristics of high transmittance (transmittance ≥85%) and low sheet resistance (0.2Ω / □~10Ω / □), realizing fast dimming, simplifying the manufacturing process and reducing the manufacturing cost, which can meet the needs of large-area practical applications.

[0017] (2) The performance of the upper and lower circuit layers can be adjusted according to different customer needs. It has the characteristics of bending resistance, so as to meet the needs of multiple fields such as home (e.g., shading), automobile (e.g., vehicle sunroof), architectural glass, flexible display devices, etc.

[0018] (3) The shape of the graphical grid can be set to a sinusoidal grid to eliminate the problem of interference fringes that occur during application, thereby making the dimming more uniform and improving the user's visual experience. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the electrochromic film of this utility model.

[0021] Figure 2 This is a schematic cross-sectional view of the electrochromic film of this utility model.

[0022] Figure 3 This is a schematic diagram of the patterned grid grooves of the circuit layer of the electrochromic film of this utility model.

[0023] Figure 4 This is a schematic diagram of the sinusoidal grid structure of the electrochromic film of this utility model.

[0024] In the figure: Electrolyte layer 1; Patterned grid groove 20; Sine grid 201; Upper circuit layer 21; Lower circuit layer 22; Upper substrate 31; Lower substrate 32. Detailed Implementation

[0025] The specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of this utility model. Based on the description of this utility model, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this utility model.

[0026] like Figures 1 to 3 As shown, this application provides an electrochromic film, comprising a lower substrate 32, a lower circuit layer 22, an electrolyte layer 1, an upper circuit layer 21, and an upper substrate 31 stacked sequentially. The upper circuit layer 21 is disposed on the side of the upper substrate 31 closest to the electrolyte layer 1, and the lower circuit layer 22 is disposed on the side of the lower substrate 32 closest to the electrolyte layer 1. Both the lower circuit layer 22 and the upper circuit layer 21 are used to form an electric field between them under the voltage of an external power supply, causing the electrolyte layer 1 to change in brightness under the influence of the electric field formed by the lower circuit layer 22 and the upper circuit layer 21.

[0027] The upper substrate 31 and the lower substrate 32 can be made of polyethylene terephthalate (PET), polycarbonate (PC), or polymethyl methacrylate (PMMA), etc. The thickness of the upper substrate 31 and the lower substrate 32 ranges from 25μm to 500μm. For example, they can be 25μm, 50μm, 85μm, 100μm, 150μm, 200μm, 250μm, 300μm, 400μm, or 500μm. The thickness of the upper substrate 31 and the lower substrate 32 can be the same or different. Different thicknesses can be customized according to actual applications. This utility model does not limit this.

[0028] The lower circuit layer 22 and the upper circuit layer 21 are made of materials such as UV adhesive or thermosetting adhesive. The thickness T of the lower circuit layer 22 and the upper circuit layer 21 ranges from 10μm to 70μm. For example, the thickness T can be 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, or 70μm. The thickness T of the lower circuit layer 22 and the upper circuit layer 21 can be the same or different. Different thicknesses T can be customized according to actual applications, and this utility model does not impose any restrictions on this.

[0029] Multiple patterned grid grooves 20 are imprinted on both the lower circuit layer 22 and the upper circuit layer 21. Specifically, the lower circuit layer 22 has patterned grid grooves 20 on the side away from the lower substrate 32, and the upper circuit layer 21 has patterned grid grooves 20 on the side away from the upper substrate 31. The patterned grid grooves 20 are filled with conductive material, which can be nano-silver, nano-copper, carbon paste, graphene, etc. The width W and depth D of the patterned grid grooves 20 are both in the range of 1μm-50μm. For example, the ratio of the depth D to the width W of the patterned grid grooves 20 can be 1:1, 1:2, or 1:3. The depth D of the patterned grid grooves 20 on the lower circuit layer 22 is less than the thickness T of the lower circuit layer 22, and the depth D of the patterned grid grooves 20 on the upper circuit layer 21 is less than the thickness T of the upper circuit layer 21. The depth D of the patterned grid grooves 20 on the upper circuit layer 21 and the lower circuit layer 22 can be the same or different, and this invention does not impose any limitation on this. The spacing between two adjacent patterned grid grooves 20 ranges from 100μm to 1000μm.

[0030] The top view shapes of the plurality of patterned grid grooves 20 in the upper circuit layer 21 and the plurality of patterned grid grooves 20 in the lower circuit layer 22 are any one of quadrilaterals, hexagons, regular polygons, sinusoids, and irregular polygons. The top view shapes of the patterned grid grooves 20 in the two circuit layers can be the same or different. In the electrochromic film of this application, the transmittance of the upper circuit layer 21 and the lower circuit layer 22 is ≥85%, and the sheet resistance ranges from 0.2Ω / □ to 10Ω / □.

[0031] Electrolyte layer 1 is disposed between lower circuit layer 22 and upper circuit layer 21, and its brightness state can be changed under the influence of the electric field of lower circuit layer 22 and upper circuit layer 21. In a feasible implementation, the electric field voltage formed between lower circuit layer 22 and upper circuit layer 21 is 30V. The alternating electric field formed by lower circuit layer 22 and upper circuit layer 21 rapidly changes the brightness of electrolyte layer 1, that is, the change from a transparent state to a colored state.

[0032] The applicant set the top view shape of the patterned grid groove 20 in the upper circuit layer 21 and the patterned grid groove 20 in the lower circuit layer 22 to be quadrilateral, obtained different sample films, conducted tests, and obtained the following results:

[0033] Performance test results 1

[0034]

[0035] By testing the transmittance and sheet resistance of a conventional electrochromic film using ITO material and the electrochromic film of this application, it can be seen that the transmittance of the conventional electrochromic film using ITO material is lower than that of the electrochromic film of this application, and the sheet resistance is higher. The electrochromic film of this application has a transmittance greater than 85% and a sheet resistance less than 4Ω / □. Because the width W of the patterned grid grooves 20 in the two circuit layers of this application is small, and the spacing between adjacent patterned grid grooves 20 is large, the electrochromic film can achieve high transmittance and low sheet resistance, realizing rapid dimming, simplifying the manufacturing process and reducing manufacturing costs, thus meeting the needs of large-area practical applications.

[0036] like Figure 4 As shown, in practical applications, especially in electrochromic displays, the combination of the circuit layer and the electrolyte layer structure may cause interference fringes. This phenomenon reduces the uniformity of the display and the visual experience, especially in transparent or semi-transparent states.

[0037] By setting the top view shape of the patterned mesh grooves 20 in the upper circuit layer 21 and the lower circuit layer 22 to a sinusoidal mesh 201, the period L of the sinusoidal mesh 201 ranges from 100µm to 500µm, the edges of the sinusoidal mesh 201 are sinusoidal curves, the difference H between the peaks and troughs of the sinusoidal curves ranges from 20µm to 100µm, and the ratio of the difference H between the peaks and troughs of the sinusoidal curves to the period L of the sinusoidal mesh ranges from 1 / 25 to 1 / 2. The applicant tested the sample and obtained the following results:

[0038] Performance Test Result 2

[0039]

[0040] By testing the transmittance and sheet resistance of sample films with different periods L, peak-to-trough differences H, and ratios of peak-to-trough differences H to period L, it can be seen that: when the ratio of the peak-to-trough difference H of the sinusoidal curve to the period L of the sinusoidal grid 201 is 1 / 3, the sheet resistance is 0.8 Ω / □, and the transmittance is 85.3%, although the sheet resistance is small, the transmittance is low; when the ratio of the peak-to-trough difference H of the sinusoidal curve to the period L of the sinusoidal grid 201 is 1 / 22, the sheet resistance is 9.4 Ω / □, and the transmittance is 89.1%, although the sheet resistance is relatively large, the transmittance is high; when the ratio of the peak-to-trough difference H of the sinusoidal curve to the period L of the sinusoidal grid 201 is 1 / 9, the electrochromic film has the best overall effect, with a transmittance of 87.8% and a sheet resistance of 3.2 Ω / □. Therefore, the larger the ratio of the difference H between the peaks and troughs of the sinusoidal curve to the period L of the sinusoidal grid 201, the lower the impedance, the smaller the sheet resistance, and the lower the transmittance; conversely, the smaller the ratio, the higher the impedance, the larger the sheet resistance, and the higher the transmittance. In practical applications, the difference H between the peaks and troughs of the sinusoidal curve and the period L of the sinusoidal grid 201 can be adjusted as needed. Using the sinusoidal grid 201 of this application can avoid interference patterns in practical applications, achieving rapid dimming while making dimming more uniform and improving the user's visual experience.

[0041] In summary, the electrochromic film of this invention overcomes the shortcomings of existing technologies using ITO material by combining a circuit layer with a patterned grid groove containing conductive material with an electrolyte layer. It features high transmittance (≥85%) and low sheet resistance (0.2Ω / □~10Ω / □), enabling rapid dimming, simplifying the manufacturing process, and reducing production costs, thus meeting the needs of large-area practical applications. The performance of the upper and lower circuit layers can be adjusted according to different customer requirements, exhibiting bend resistance to meet the needs of various fields such as home use (e.g., shading), automotive (e.g., vehicle sunroofs), architectural glass, and flexible display devices. Furthermore, by setting the shape of the patterned grid to a sinusoidal grid, interference fringes are eliminated during application, resulting in more uniform dimming and improved user visual experience.

[0042] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model.

Claims

1. An electrochromic film, characterized by, The device comprises a lower substrate, a lower circuit layer, an electrolyte layer, an upper circuit layer, and an upper substrate stacked sequentially. Both the lower circuit layer and the upper circuit layer have multiple patterned grid grooves filled with conductive material. The patterned grid grooves are located on the side of the lower circuit layer away from the lower substrate and on the side of the upper circuit layer away from the upper substrate. The lower circuit layer and the upper circuit layer are used to form an electric field under the voltage of an external power supply, causing the electrolyte layer to produce light and dark changes.

2. The electrochromic film as described in claim 1, characterized in that, The width and depth of the patterned mesh grooves range from 1μm to 50μm.

3. The electrochromic film as described in claim 1, characterized in that, The spacing between two adjacent patterned grid grooves ranges from 100μm to 1000μm.

4. The electrochromic film as described in claim 1, characterized in that, The thickness range of the lower circuit layer and the upper circuit layer is 10μm~70μm. The depth of the patterned grid groove on the lower circuit layer is less than the thickness of the lower circuit layer, and the depth of the patterned grid groove on the upper circuit layer is less than the thickness of the upper circuit layer.

5. The electrochromic film as described in claim 1, characterized in that, The transmittance of the lower circuit layer and the upper circuit layer is ≥85%.

6. The electrochromic film as described in claim 1, characterized in that, The sheet resistance range of the lower circuit layer and the upper circuit layer is 0.2Ω / □~10Ω / □.

7. The electrochromic film as described in claim 1, characterized in that, The top view shape of the graphical grid groove is a quadrilateral, hexagon, regular polygon, sine, or irregular polygon.

8. The electrochromic film as described in claim 1, characterized in that, The top view shape of the graphic grid groove is a sinusoidal grid, and the period of the sinusoidal grid ranges from 100µm to 500µm.

9. The electrochromic film as described in claim 8, characterized in that, The edges of the sinusoidal grid are sinusoidal curves, and the difference between the peaks and troughs of the sinusoidal curves ranges from 20µm to 100µm.

10. The electrochromic film as described in claim 9, characterized in that, The ratio of the difference between the peaks and troughs of the sinusoidal curve to the period of the sinusoidal grid ranges from 1 / 25 to 1 / 2.

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