Conductive film and electrochromic film

Abstract

The utility model discloses a conducting film and an electrochromic film. The conducting film comprises a first resin layer, a base material layer, a second resin layer, a transition layer, a first ITO layer, a gold layer and a second ITO layer which are sequentially arranged in a stacked mode. Wherein the refractive index of the second resin layer is greater than or equal to the refractive index of the first resin layer, the absolute value of the difference between the thickness H1 of the first ITO layer and the thickness H2 of the second ITO layer is greater than or equal to (H1 + H2) / 2, and the sheet resistance of the conductive film is 2.5-4 omega. The two ITO layers with the asymmetric thicknesses are arranged on the two sides of the gold layer, a parallel circuit is formed, the ultralow-sheet-resistance conducting film can be obtained, meanwhile, the thickness difference value of the two ITO layers is larger than half of the total thickness of the two ITO layers, the asymmetric design is obtained based on optical matching, and the light transmittance of the conducting film can be remarkably improved.

Description

Technical Field

[0001] This application belongs to the field of electrochromic technology, specifically relating to a conductive film and an electrochromic film. Background Technology

[0002] With the development of intelligent and electric vehicles, the intelligent configuration experience in different scenarios has become a major focus for many consumers. Among them, panoramic heat-insulating color-changing sunroofs need to balance heat insulation and adjustable brightness. Currently, only EC electrochromic technology can meet the requirements of panoramic heat-insulating color-changing sunroofs for sun protection performance and color-changing effect.

[0003] In panoramic thermal insulation EC color-changing canopy, a conductive film acts as an electrode to uniformly apply voltage to the electrochromic material, driving ion implantation or extraction and triggering a redox reaction to achieve color change. Because the operating voltage of the panoramic thermal insulation EC color-changing canopy is as low as below 1.5V, the impedance requirements for the conductive film are relatively high; at the same time, to improve the user experience, high requirements are placed on the thermal insulation performance, conductivity, and transmittance of the conductive film.

[0004] Conventional ITO films require increased thickness to meet impedance requirements, resulting in very high costs. Currently, the lowest sheet resistance ITO film on the market, at 300nm thick, has an impedance of around 6Ω and low transmittance, failing to meet the requirements. Symmetrical IMI films with ITO layers sandwiching Ag layers can meet the transmittance requirements, but they cannot effectively control metal oxidation, affecting product stability and lifespan. Existing metal mesh materials can achieve ultra-low resistance and high transmittance, but when applied to electrochromic materials, they cannot withstand the corrosive effects of the color-changing materials and have poor environmental reliability. Utility Model Content

[0005] The purpose of this application is to provide a conductive film and an electrochromic film to solve the technical problem that existing conductive films cannot simultaneously meet the requirements of heat insulation performance, conductivity performance and transmittance, and thus cannot meet the needs of panoramic heat insulation EC color-changing skylights.

[0006] To achieve the above objectives, the first aspect of this application provides a conductive film comprising a first resin layer, a substrate layer, a second resin layer, a transition layer, a first ITO layer, a gold layer, and a second ITO layer stacked sequentially.

[0007] Wherein, the refractive index of the second resin layer is greater than or equal to the refractive index of the first resin layer, the absolute value of the difference between the thickness H1 of the first ITO layer and the thickness H2 of the second ITO layer is greater than or equal to (H1+H2) / 2, and the sheet resistance of the conductive film is 2.5~4 Ω.

[0008] In one or more embodiments, the sum of the thicknesses of the first ITO layer and the second ITO layer is 280~310 nm.

[0009] In one or more embodiments, the absolute value of the difference between the thickness H1 of the first ITO layer and the thickness H2 of the second ITO layer is greater than or equal to 2(H1+H2) / 3.

[0010] In one or more embodiments, the thickness of the first ITO layer is 240-260 nm, and the thickness of the second ITO layer is 40-50 nm.

[0011] In one or more embodiments, the thickness of the first ITO layer is 40-50 nm, and the thickness of the second ITO layer is 240-260 nm.

[0012] In one or more embodiments, the thickness of the gold layer is 5-8 nm.

[0013] In one or more embodiments, the substrate layer is a PET substrate layer with a thickness of 20~200 μm.

[0014] In one or more embodiments, the transition layer is one of a single-element silicon layer, a silicon oxide layer, and an aluminum oxide layer, and the thickness of the transition layer is 1~2 nm.

[0015] In one or more embodiments, the refractive index of the first resin layer is 1.5 to 1.55, and the thickness is 0.8 to 1.0 μm.

[0016] In one or more embodiments, the refractive index of the second resin layer is 1.5 to 1.55, and the thickness is 0.8 to 1.0 μm.

[0017] In one or more embodiments, the refractive index of the second resin layer is 1.62 to 1.68, and the thickness is 0.8 to 1.0 μm.

[0018] In one or more embodiments, a surface conditioning layer is further included, disposed between the first ITO layer and the gold layer, wherein the surface conditioning layer is a zinc aluminum oxide layer or a niobium pentoxide layer, and the thickness is 8-10 nm.

[0019] To achieve the above objectives, a second aspect of this application provides an electrochromic film, comprising a color-changing material layer and a conductive film as described in any of the above embodiments;

[0020] The conductive film is arranged on both sides of the color-changing material layer.

[0021] The advantages of this application, which differ from existing technologies, are:

[0022] This application obtains an ultra-low sheet resistance conductive film by setting two ITO layers with asymmetrical thickness on both sides of the gold layer to form a parallel circuit. At the same time, the thickness difference between the two ITO layers is greater than half of the total thickness of the two layers. This asymmetrical design is based on optical matching and can significantly improve the light transmittance of the conductive film.

[0023] This application uses Au material as the metal layer, which can effectively avoid the metal layer from being corroded and oxidized during electrochromism, improve the stability and service life of the conductive film, and help improve the thermal insulation performance and weather resistance of the conductive film.

[0024] Based on the design of the refractive index and thickness of the first resin layer and the second resin layer, the light transmittance of the conductive film can be improved through optical matching.

[0025] This application provides a surface conditioning layer on the surface of the ITO layer, which can provide a flatter growth surface for the gold layer, thereby helping to improve the thickness uniformity and continuity of the gold layer and improve the performance of the conductive film. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of one embodiment of the conductive film of this application;

[0028] Figure 2 This is a schematic diagram of another embodiment of the conductive film of this application;

[0029] Figure 3 This is a schematic diagram of the structure of one embodiment of the electrochromic film of this application;

[0030] Figure 4 These are partial SEM images of the conductive films of Embodiments 2 and 3 of this application.

[0031] Explanation of key figure labels:

[0032] Conductive film 1: First resin layer 10; Substrate layer 20; Second resin layer 30; Transition layer 40; First ITO layer 50; Gold layer 60; Second ITO layer 70; Surface conditioning layer 80;

[0033] Color-changing material layer 2. Detailed Implementation

[0034] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0035] The impedance requirement for conductive film in panoramic heat-insulating EC color-changing canopy is a sheet resistance of about 3 Ω. Pure ITO conductive film cannot meet the requirements. Symmetrical IMI film with ITO layer sandwiched with Ag layer cannot effectively control metal oxidation, affecting the stability and service life of the product. Metal mesh material is also difficult to apply to EC color-changing canopy because it cannot resist the corrosion of color-changing material and has poor environmental reliability.

[0036] To this end, the applicant provides a novel conductive film that, through layer structure design and optical matching of the thickness of each layer, can meet the requirements of ultra-low sheet resistance and high light transmittance, and has excellent environmental weather resistance, avoiding problems such as oxidation and corrosion during the color-changing process. It can be applied to the electrochromic film of panoramic heat insulation EC color-changing sky screen to meet performance requirements.

[0037] Specifically, please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of one embodiment of the conductive film of this application.

[0038] like Figure 1 As shown, the conductive film 1 includes a first resin layer 10, a substrate layer 20, a second resin layer 30, a transition layer 40, a first ITO layer 50, a gold layer 60, and a second ITO layer 70, which are stacked sequentially.

[0039] The refractive index of the second resin layer 30 is greater than or equal to the refractive index of the first resin layer 10.

[0040] The absolute value of the difference between the thickness H1 of the first ITO layer 50 and the thickness H2 of the second ITO layer 70 is greater than or equal to (H1+H2) / 2.

[0041] Based on the above structure, by setting two ITO layers with asymmetrical thickness on both sides of the gold layer 60, a parallel circuit is formed to achieve superconductivity. This results in an ultra-low sheet resistance conductive film with a sheet resistance of 2.5~4 Ω. At the same time, the thickness difference between the two ITO layers is greater than half of their total thickness. This asymmetrical design is based on optical matching and can significantly improve the light transmittance of the conductive film 1.

[0042] Furthermore, in one embodiment, the absolute value of the difference between the thickness H1 of the first ITO layer 50 and the thickness H2 of the second ITO layer 70 is greater than or equal to 2(H1+H2) / 3, further optimizing the light transmittance of the conductive film 1.

[0043] Specifically, in one embodiment, the sum of the thicknesses of the first ITO layer 50 and the second ITO layer 70 can be 280~310 nm.

[0044] In one embodiment, the thickness of the first ITO layer 50 may be greater than that of the second ITO layer 70, wherein the thickness of the first ITO layer 50 may be 240-260 nm and the thickness of the second ITO layer 70 may be 40-50 nm.

[0045] In another embodiment, the thickness of the second ITO layer 70 can be greater than that of the first ITO layer 50, wherein the thickness of the first ITO layer 50 can be 40~50 nm and the thickness of the second ITO layer 70 can be 240~260 nm.

[0046] Preferably, the thickness of the outermost second ITO layer 70 can be less than that of the first ITO layer 50, thereby giving the conductive film 1 a better transmittance.

[0047] Furthermore, this embodiment uses Au material as the metal layer. Since the electrochromic layer contains an electrolyte containing corrosive ions such as chloride and fluoride ions, and existing conductive films use silver as the metal layer, silver itself has a low electrode potential of only about +0.799V, making it easily corroded. In contrast, gold has a relatively high electrode potential of about +1.52V, which can effectively avoid corrosion and oxidation of the metal layer during electrochromism, thus improving the stability and service life of the conductive film 1, and also helping to improve the thermal insulation performance and weather resistance of the conductive film 1.

[0048] In one embodiment, the thickness of the gold layer 60 can be 5~8 nm.

[0049] Furthermore, this application also improves the light transmittance of the conductive film 1 through optical matching based on the refractive index design of the first resin layer 10 and the second resin layer 30.

[0050] In one embodiment, the refractive index of the first resin layer 10 can be 1.5 to 1.55, and the thickness can be 0.8 to 1.0 μm.

[0051] In one embodiment, the refractive index of the second resin layer 30 may be higher than that of the first resin layer 10. Specifically, the refractive index of the second resin layer 30 may be 1.62 to 1.68, and the thickness may be 0.8 to 1.0 μm.

[0052] In another embodiment, the refractive index of the second resin layer 30 may be substantially the same as that of the first resin layer 10. Specifically, the refractive index of the second resin layer 30 may be 1.5 to 1.55, and the thickness may be 0.8 to 1.0 μm.

[0053] In this embodiment, the transition layer 40 can be made of one of elemental silicon, silicon oxide, and aluminum oxide, and its thickness can be 1~2 nm.

[0054] Preferably, the transition layer 40 can be made of elemental silicon, so that the transition layer 40 can be obtained by magnetron sputtering under a single atmosphere, thereby simplifying the sputtering process and improving production efficiency.

[0055] In this embodiment, the substrate layer 20 can be any substrate material that meets the transmittance requirements, such as PET, PC, PMMA, etc. In one embodiment, the substrate layer 20 can be a PET substrate layer 20 with a thickness of 20~200 μm.

[0056] In the above embodiments, the gold layer 60 is directly disposed on the surface of the first ITO layer 50. Due to the high surface roughness of the ITO layer, the surface of the gold layer 60 may be uneven after deposition, resulting in inconsistent thickness and poor surface continuity. Although the impact on the overall impedance of the film is relatively small, it will cause the current to pass through a "rough" path, resulting in uneven current distribution, which will intensify electron scattering, increase local resistance, or reduce overall conductivity, which is not conducive to the deposition of subsequent materials and thus affects the overall performance of the conductive film 1.

[0057] To address this issue, in another embodiment, a surface conditioning layer 80 can be disposed between the first ITO layer 50 and the gold layer 60. The surface conditioning layer 80 reduces surface roughness, making the current path smoother and reducing electron scattering. (See also...) Figure 2 , Figure 2 This is a schematic diagram of another embodiment of the conductive film 1 of this application.

[0058] like Figure 2 As shown, in this embodiment, the conductive film 1 further includes a surface conditioning layer 80 disposed between the first ITO layer 50 and the gold layer 60. The surface conditioning layer 80 can be made of zinc aluminum oxide or niobium pentoxide, and its thickness can be 8~10 nm.

[0059] By setting the surface adjustment layer 80, a flatter growth surface can be provided for the gold layer 60, which helps to improve the thickness uniformity and continuity of the gold layer 60, avoid electron scattering, and help improve the performance of the conductive film 1.

[0060] This application also provides an electrochromic film using the conductive film 1 of any of the above embodiments as an electrode. Please refer to [link to relevant documentation]. Figure 3 , Figure 3 This is a schematic diagram of the structure of one embodiment of the electrochromic film of this application.

[0061] like Figure 3 As shown, the electrochromic film includes a color-changing material layer 2 and conductive films 1 disposed on both sides of the color-changing material layer 2. The second ITO layer 70 of the conductive film 1 can be disposed on the side closest to the color-changing material layer 2, thereby uniformly applying voltage to the color-changing material layer 2.

[0062] Specifically, in this embodiment, the color-changing material layer 2 can be any color-changing material commonly used in the art, such as tungsten trioxide, nickel oxide, etc., and its thickness can be adjusted according to actual needs, which will not be elaborated here.

[0063] This application also provides a method for preparing the conductive film 1 according to any of the above embodiments. Specifically, the preparation method includes:

[0064] S100. Apply resin to both sides of the substrate layer 20 to obtain the first resin layer 10 and the second resin layer 30.

[0065] S200, different metal materials are sputtered onto the surface of the second resin layer 30 to obtain a transition layer 40, a first ITO layer 50, a gold layer 60, and a second ITO layer 70.

[0066] The transition layer 40, the first ITO layer 50, the gold layer 60, and the second ITO layer 70 can be prepared sequentially by magnetron sputtering. The target material and parameters of magnetron sputtering can be adjusted according to actual needs, which will not be elaborated here.

[0067] In one embodiment, the first ITO layer 50 and the second ITO layer 70 can be sputtered in a mixed atmosphere of krypton and oxygen. By using krypton as the bombardment gas and oxygen as the reaction gas, the film thickness of the first ITO layer 50 and the second ITO layer 70 can be reduced without changing the impedance. The thinner the film thickness, the higher the overall transmittance, thus improving the transmittance of the conductive film.

[0068] The main principle is as follows: The sputtering atmosphere of conventional ITO layers is a mixture of argon and oxygen. In this embodiment, krypton is used instead of conventional argon. Krypton has a lower ionization voltage than argon, and can start arcing at a lower voltage. Therefore, compared with conventional coating using argon as the bombardment gas, krypton has a higher ionization rate, which leads to a denser coating layer. This allows for a reduction in film thickness and an increase in light transmittance while achieving the same impedance.

[0069] Furthermore, since higher oxygen content leads to lower coating efficiency, the ratio of krypton to oxygen needs to be considered comprehensively to ensure overall efficiency and coating cost. Specifically, in this scheme, the krypton flow rate can be 500~600 sccm, and the krypton to oxygen flow rate ratio can be (28~30):1.

[0070] In one embodiment, to avoid the continuity of the gold layer 60 being affected by the rough surface of the first ITO layer 50, a metal material can be sputtered onto the surface of the first ITO layer 50 before the step of sputtering to obtain the gold layer 60, to obtain a surface conditioning layer 80.

[0071] The beneficial effects of the technical solution of this application will be further described in detail below with reference to specific embodiments.

[0072] Example 1:

[0073] A conductive film, with the following structure Figure 1 As shown. The first resin layer has a refractive index of 1.5 and a thickness of 0.8 μm, using resin type Lien and NOA1504; the substrate layer is a 125 μm thick PET layer; the second resin layer has a refractive index of 1.62 and a thickness of 0.8 μm, using resin type Lien and NOA165H; the transition layer is a 0.5 nm thick silicon layer; the first ITO layer has a thickness of 240 nm; the gold layer has a thickness of 5 nm; and the second ITO layer has a thickness of 40 nm.

[0074] The conductive film was prepared using the following steps:

[0075] Step 1: Apply resin to both sides of the substrate layer to obtain the first resin layer and the second resin layer;

[0076] Step 2: Sputter metallic silicon onto the surface of the second resin layer to obtain a transition layer. Sputtering parameters: vacuum degree 7.0 × 10⁻⁶. -4 Below Pa, water vapor content is 1.0 × 10⁻⁶. -4 Below Pa, silicon purity 5N, travel speed 1.0~2.0 m / min, medium frequency sputtering power 0.5~1.0 kW, argon flow rate 200~300 sccm;

[0077] Step 3: Sputter metal onto the transition layer surface to obtain the first ITO layer. Sputtering parameters: indium oxide 90 wt%, tin oxide 10 wt%, flow rate 1.5~2.0 m / min, AE 30 kW, DC power 10~12 kW, DC sputtering, 4 sputtering targets, krypton flow rate 500~600 sccm, krypton to oxygen flow rate ratio 30:1.

[0078] Step 4: Sputter gold onto the surface of the first ITO layer to obtain a gold layer. Sputtering parameters: run speed 1.0~2.0 m / min, using a Hotting Hipims power supply with DC sputtering power of 3~5 kW and argon flow rate of 200~400 sccm.

[0079] Step 5: Sputter metal onto the gold layer surface to obtain the second ITO layer. The sputtering parameters are the same as in Step 3.

[0080] Example 2:

[0081] A conductive film, with the following structure Figure 2 As shown. The first resin layer has a refractive index of 1.5 and a thickness of 1.0 μm, using resin type Lien and NOA1504; the substrate layer is a 125 μm thick PET layer; the second resin layer has a refractive index of 1.62 and a thickness of 1.0 μm, using resin type Lien and NOA165H; the transition layer is a 1.0 nm thick silicon layer; the first ITO layer is 260 nm thick; the surface conditioning layer is a 10 nm thick zinc-aluminum oxide layer; the gold layer is 8 nm thick; and the second ITO layer is 50 nm thick.

[0082] The preparation method of this conductive film is basically the same as that in Example 1, except that:

[0083] Before step four, the process also includes sputtering metal onto the surface of the first ITO layer to obtain a surface conditioning layer. The sputtering parameters are: a zinc oxide to aluminum oxide mass ratio of 95:5, a travel speed of 1.0~2.0 m / min, a DC power of 12~15 kW, an argon flow rate of 200~300 sccm, and an argon to oxygen flow rate ratio of 10:1.

[0084] Example 3:

[0085] A conductive film, with a structure basically the same as that in Example 2, differs in that:

[0086] No surface conditioning layer.

[0087] Example 4:

[0088] A conductive film, with the following structure Figure 2 As shown. The first resin layer has a refractive index of 1.5 and a thickness of 1.0 μm, using resin type Lien and NOA1504; the substrate layer is a 125 μm thick PET layer; the second resin layer has a refractive index of 1.62 and a thickness of 1.0 μm, using resin type Lien and NOA165H; the transition layer is a 1.0 nm thick silicon oxide layer; the first ITO layer is 50 nm thick; the surface conditioning layer is a 10 nm thick zinc-aluminum oxide layer; the gold layer is 8 nm thick; and the second ITO layer is 260 nm thick.

[0089] Example 5:

[0090] A conductive film, with a structure basically the same as that in Example 4, differs in that:

[0091] The surface conditioning layer is a 10 nm thick niobium pentoxide layer; the transition layer is a 1.0 nm thick aluminum oxide layer.

[0092] Comparative Example 1:

[0093] A conductive film, with a structure basically the same as that in Example 2, differs in that:

[0094] A 300nm thick ITO layer was used to replace the first ITO layer, gold layer, surface conditioning layer and second ITO layer in Example 2.

[0095] Comparative Example 2:

[0096] A conductive film includes a substrate layer and a copper layer stacked sequentially, wherein the substrate layer is a 125 μm thick PET layer and the copper layer is 400 nm thick.

[0097] Comparative Example 3:

[0098] A conductive film, with a structure basically the same as that in Example 2, differs in that:

[0099] The thickness of both the first ITO layer and the second ITO layer is 150 nm.

[0100] The gold layer in Example 2 was replaced with an 8 nm thick silver layer.

[0101] Comparative Example 4:

[0102] A conductive film, with a structure basically the same as that in Example 2, differs in that:

[0103] The gold layer in Example 2 was replaced with an 8 nm thick silver layer.

[0104] Comparative Example 5:

[0105] A conductive film, with a structure basically the same as that in Example 3, differs in that:

[0106] The thickness of both the first and second ITO layers is 150 nm.

[0107] Comparative Example 6:

[0108] A conductive film, with a structure basically the same as that in Example 3, differs in that:

[0109] The thickness of the first ITO layer is 220 nm, and the thickness of the second ITO layer is 80 nm. The difference in thickness between the two is 140 nm, which is less than half of the total thickness of the two layers, 150 nm.

[0110] Comparative Example 7:

[0111] A conductive film, with the same structure as in Example 3, but prepared using a different method, is described below:

[0112] When depositing the first ITO layer and the second ITO layer, the ratio of krypton to oxygen is 25:1.

[0113] Example 1: Characterization Analysis

[0114] The conductive films of Examples 2 and 3 were characterized and analyzed to obtain... Figure 4 , Figure 4 These are partial SEM images of the conductive films of Embodiments 2 and 3 of this application.

[0115] like Figure 4 As shown, the surface of the first ITO layer in Example 3 is crystalline with a surface roughness of 4-5 nm; while the surface of the zinc oxide aluminum layer in Example 2 is amorphous with a surface roughness of only 1 nm, which can provide a flatter growth surface for the gold layer and significantly improve the uniformity of the gold layer.

[0116] Example 2:

[0117] The impedance, reflectivity, transmittance, and heat insulation rate of the conductive films of Examples 1 to 5 and Comparative Examples 1 to 7 were measured respectively. At the same time, in order to verify the weather resistance and stability of the conductive films, the impedance stability of the conductive films under electrochemical reaction conditions, salt spray conditions, and high temperature and high humidity conditions was also tested.

[0118] Specifically, impedance was measured using a Daming square resistance meter (ASTM D991); reflectivity was measured using an Olympus reflectance meter (wavelength 380~780 nm); transmittance was tested using an NDH5000 haze meter; heat insulation rate was measured using an LS182 solar film tester (wavelength 850~4000 nm); electrochemical reaction conditions were tested by immersing the conductive film in 10 wt% lithium hexafluorophosphate; salt spray conditions were simulated in a salt spray test chamber using 5 wt% NaCl; and high temperature and high humidity conditions were simulated in a high temperature and high humidity test chamber using 85 ℃ and 85 RH.

[0119] Please refer to the table below for the data of the above embodiments and comparative examples.

[0120]

[0121] As shown in the table above, the conductive films of Examples 1 to 5 have a sheet resistance of about 3.5 Ω, a transmittance of about 80%, and a heat insulation rate of about 60%. They can balance ultra-low sheet resistance, high light transmittance, and high heat insulation performance. Furthermore, they can maintain their impedance and appearance unchanged for 100 h under electrochemical conditions, salt spray conditions, and high temperature and humidity conditions, demonstrating excellent weather resistance.

[0122] Comparative Example 1 uses a pure ITO layer as the conductive layer, with a sheet resistance as high as 6 Ω, which cannot meet the requirements.

[0123] Comparative Example 2 uses pure copper as the conductive layer. The sheet resistance and transmittance can meet the requirements, but the heat insulation performance and weather resistance are poor and cannot meet the requirements.

[0124] Comparative Example 3 adopts a symmetrical conductive layer structure, which can meet the requirements of sheet resistance, but has poor transmittance and thermal insulation performance. At the same time, since Comparative Example 3 uses silver as a metal layer, it is easy to oxidize and has poor salt spray resistance.

[0125] Comparative Example 4 uses silver as the metal layer, which is easily oxidized, susceptible to electrochemical corrosion, and has poor electrochemical stability and salt spray resistance.

[0126] Comparative Example 5 uses a symmetrical conductive layer structure, which can meet the sheet resistance requirements, but has poor transmittance and thermal insulation performance.

[0127] In Comparative Example 6, the thickness difference between the first ITO layer and the second ITO layer is 140 nm, which is less than half of the total thickness of the two layers, 150 nm. This results in a high reflectivity and low transmittance of the conductive film, which cannot meet the requirements.

[0128] In Comparative Example 7, the proportion of krypton gas in the first ITO layer and the proportion of oxygen gas in the coating process of the second ITO layer is too low and the proportion of oxygen gas is too high. After the proportion of oxygen gas increases, the impedance increases and the sputtering efficiency slows down. Therefore, a larger film thickness is required to achieve ultra-low sheet resistance, resulting in excessively high impedance of the conductive film in Comparative Example 7.

[0129] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0130] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A conductive film, characterized in that, It includes a first resin layer, a substrate layer, a second resin layer, a transition layer, a first ITO layer, a gold layer, and a second ITO layer, which are stacked sequentially. Wherein, the refractive index of the second resin layer is greater than or equal to the refractive index of the first resin layer, and the absolute value of the difference between the thickness H1 of the first ITO layer and the thickness H2 of the second ITO layer is greater than or equal to (H1+H2) / 2. The sheet resistance of the conductive film is 2.5~4 Ω.

2. The conductive film according to claim 1, characterized in that, The sum of the thicknesses of the first ITO layer and the second ITO layer is 280~310 nm.

3. The conductive film according to claim 2, characterized in that, The absolute value of the difference between the thickness H1 of the first ITO layer and the thickness H2 of the second ITO layer is greater than or equal to 2(H1+H2) / 3.

4. The conductive film according to claim 1, characterized in that, The thickness of the first ITO layer is 240~260 nm, and the thickness of the second ITO layer is 40~50 nm; or, The thickness of the first ITO layer is 40~50 nm, and the thickness of the second ITO layer is 240~260 nm.

5. The conductive film according to claim 1, characterized in that, The thickness of the gold layer is 5-8 nm; and / or, The substrate layer is a PET substrate layer with a thickness of 20~200 μm.

6. The conductive film according to claim 1, characterized in that, The transition layer is one of a single-element silicon layer, a silicon oxide layer, and an aluminum oxide layer, and the thickness of the transition layer is 1~2 nm.

7. The conductive film according to claim 1, characterized in that, The first resin layer has a refractive index of 1.5~1.55 and a thickness of 0.8~1.0 μm.

8. The conductive film according to claim 1, characterized in that, The second resin layer has a refractive index of 1.5~1.55 and a thickness of 0.8~1.0 μm; or, The refractive index of the second resin layer is 1.62~1.68, and the thickness is 0.8~1.0 μm.

9. The conductive film according to claim 1, characterized in that, It also includes a surface conditioning layer disposed between the first ITO layer and the gold layer, wherein the surface conditioning layer is a zinc aluminum oxide layer or a niobium pentoxide layer with a thickness of 8~10 nm.

10. An electrochromic film, characterized in that, Includes a color-changing material layer and a conductive film as described in any one of claims 1 to 9; The conductive film is arranged on both sides of the color-changing material layer.

Images