TWI839877B - Manufacturing method of electrochromic film - Google Patents

Abstract

The present disclosure provides a manufacturing method for an electrochromic thin film. The manufacturing method includes: performing a film-forming step including forming a film-like laminate, in which the film-like laminate includes a first conductive film, a color-changing reduction layer, a solid-state electrolyte layer, a color-changing oxididation layer, and a second conductive film stacked in sequence, and a material of the color-changing reduction layer includes tungsten oxide; performing a cutting step including cutting off the second conductive film material, the color-changing oxididation layer, and the solid-state electrolyte layer on a first side of the film-like laminate, such that the color-changing reduction layer on the first side is exposed; performing a removing step including using a first solution to remove the exposed color-changing reduction layer, such that a portion of the first conductive film is exposed, in which the first solution includes sodium hydroxide, hydrogen peroxide, and water; and performing a coating step including forming a first electrode on a surface of the exposed first conductive film.

Description

Method for manufacturing electrochromic film

This disclosure relates to a method for manufacturing an electrochromic film.

Currently, most electrochromic components on the market use hard materials such as glass substrates as the base layer, which makes it impossible to store electrochromic components during the production process. They can only be implemented in an independent sheet-type structure. Independent sheet-type electrochromic components are not conducive to mass production and their production capacity is relatively limited. Electrochromic components with sheet-type structures are easily limited in application due to the size, shape and bending (curved surface) of the material and cannot be widely used. In addition, in order to adapt to the size of the object during application, waste is easily generated after cutting.

According to some embodiments of the present disclosure, the present disclosure provides a method for manufacturing an electrochromic film, comprising: performing a film forming step, comprising forming a film-like stack, wherein the film-like stack comprises a first conductive film material, a color-changing reduction layer, a solid electrolyte layer, a color-changing oxide layer and a second conductive film material stacked in sequence, and the material of the color-changing reduction layer comprises tungsten oxide; performing a cutting step, comprising cutting the first side of the film-like stack to form a second conductive film material; The second conductive film material, the color-changing oxide layer and the solid electrolyte layer are removed to expose the color-changing reduction layer on the first side; a cleaning step is performed, including using a first solution to remove the exposed color-changing reduction layer to expose part of the first conductive film material, wherein the first solution includes sodium hydroxide, hydrogen peroxide and water; and a coating step is performed, including forming a first electrode on the surface of the exposed first conductive film material.

In some embodiments of the present disclosure, the cutting step further includes: removing the first conductive film material, the color-changing reduction layer, and the solid electrolyte layer on the second side of the film-like stack, so that the color-changing oxide layer on the second side is exposed.

In some embodiments of the present disclosure, the material of the color-changing oxide layer includes nickel oxide, and the cleaning step further includes: using a second solution to remove the exposed color-changing oxide layer to expose a portion of the second conductive film material, wherein the second solution includes nitric acid, citric acid, hydrogen peroxide and water.

In some embodiments of the present disclosure, in the second solution, the content of nitric acid is between 15 parts by weight and 40 parts by weight, the content of citric acid is between 0.5 parts by weight and 10 parts by weight, and the content of hydrogen peroxide is between 1 part by weight and 10 parts by weight.

In some embodiments of the present disclosure, the method for manufacturing the electrochromic film further includes: adjusting the pH value of the first solution so that the pH value of the first solution is between 8.0 and 10.0; and adjusting the pH value of the second solution so that the pH value of the second solution is between 1.0 and 3.0.

In some embodiments of the present disclosure, in the first solution, the content of sodium hydroxide is between 15 parts by weight and 40 parts by weight, and the content of hydrogen peroxide is between 2 parts by weight and 10 parts by weight.

In some embodiments of the present disclosure, the exposed discolored reduction layer is removed by wiping in the removal step.

In some embodiments of the present disclosure, there is a gap between the first electrode formed in the coating step and the solid electrolyte layer.

In some embodiments of the present disclosure, the method for manufacturing the electrochromic film further includes: forming an edge sealing structure in the gap, wherein the material of the edge sealing structure includes acrylic resin, epoxy resin or a combination thereof.

In some embodiments of the present disclosure, the edge sealing structure covers the top surface of the first electrode.

According to the above-mentioned implementation method of the present disclosure, the present disclosure completely removes the residual color-changing oxidation/reduction layer in a short time through a special process method (cleaning method), which is not only conducive to stably forming the electrode in the electrochromic film, but also can greatly improve the convenience of the process.

1000:Electrochromic film

100: Membrane layer

110: The first conductive film material

111: Surface

115: Base material

116: Surface

117: Indium tin oxide conductive film

118: Surface

120: Color-changing restoration layer

121: Surface

130: Second conductive film material

131: Surface

135: Base material

136: Surface

137: Indium tin oxide conductive film

138: Surface

140: Color-changing oxide layer

141: Surface

150: Solid electrolyte layer

160: Hardening layer

170: Edge banding structure

G: ion conducting colloid

M: Sprayer

P1: First pressing wheel

P2: Second pressing wheel

R1: First conveyor wheel

R2: Second conveyor wheel

H1,H2,H3,H4,H5,H6,H7:Thickness

d: Spacing

S: Side wall

S1: First side

S2: Second side

A1: First electrode region

A2: Second electrode area

E1: First electrode

E2: Second electrode

E1T,E2T: Top surface

SP: Gap

U: Ultraviolet light source

C: Curved side wall

S10~S50: Steps

A-A': line segment

In order to make the above and other purposes, features, advantages and embodiments of the present disclosure more clearly understandable, the attached drawings are described as follows: FIG. 1 is a flow chart of a method for manufacturing an electrochromic film according to some embodiments of the present disclosure; FIG. 2 is a schematic diagram of a process of a film-like stack according to some embodiments of the present disclosure; FIG. 3A is a three-dimensional schematic diagram of a film-like stack according to some embodiments of the present disclosure; FIG. 3B is a schematic diagram of a cross-section of the film-like stack of FIG. 3A taken along line segment A-A'; FIG. 4A, FIG. 4B and FIG. 4C are schematic diagrams of cross-sections of an electrochromic film according to some embodiments of the present disclosure at different stages during the process; and FIG. 5A to FIG. 5C are schematic diagrams of top views of an electrochromic film according to some embodiments of the present disclosure in different embodiments during the process.

The following will disclose multiple implementations of the present disclosure. For the sake of clarity, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present disclosure. In other words, in some implementations of the present disclosure, these practical details are not necessary and therefore should not be used to limit the present disclosure.

It should be understood that relative terms such as "lower" or "bottom" and "upper" or "top" may be used herein to describe the relationship of one element to another element, as shown in the drawings. It should be understood that relative terms are intended to include different orientations of the device in addition to the orientation shown in the drawings. For example, if the device in a figure is flipped, the elements described as being on the "lower" side of other elements will be oriented on the "upper" side of the other elements. Therefore, the exemplary term "lower" can include both "lower" and "upper" orientations, depending on the particular orientation of the figure. Similarly, if the device in a figure is flipped, the elements described as being "lower" or "below" other elements will be oriented as being "above" the other elements. Therefore, the exemplary term "lower" or "below" can include both "upper" and "lower" orientations.

The present disclosure provides a method for manufacturing an electrochromic film, which integrates the manufacturing process of the electrochromic film into a roll-to-roll process through a special process improvement. In this way, not only can the production efficiency and yield be improved, the emission of waste gas or waste liquid be avoided, and the convenience of storage and transportation be improved, but also a roll-shaped electrochromic film can be formed to replace the traditional plate (sheet)-shaped electrochromic element. In this way, the rolled electrochromic film can be directly cut into a suitable shape and size according to the design of the back end, so that the entire electrochromic film manufacturing method is not limited by the final shape, size and curvature of the electrochromic film when it is used. In addition, the rolled electrochromic film can be completely removed from the residual color-changing oxidation/reduction layer in a short time through the special process method (cleaning method) disclosed in the present invention after cutting, which is not only conducive to stably forming the electrode in the electrochromic film, but also greatly improves the convenience of the process. In addition, the electrochromic film prepared by the manufacturing method disclosed in the present invention can save the configuration of the frame glue (frame), that is, there is no need to introduce additional frame glue to prevent the electrolyte in the electrochromic film from leaking out, thereby greatly improving the applicability and installation convenience of the electrochromic film, so that the electrochromic film can be applied to a variety of fields. The electrochromic film disclosed herein can be applied to building curtain glass, skylights, smart windows, interior partition walls, car rearview mirrors or exterior mirrors, car sunroofs, side windows and windshields (applied in cars, large land transportation vehicles, MRT, trams, high-speed rail, airplanes, ships, etc.), personal wearable lenses (photochromic lenses, snow goggles, safety goggles), helmet lenses, 3C virtual reality goggles, and many other fields.

Please refer to FIG. 1, which shows a flow chart of a method for manufacturing an electrochromic film according to some embodiments of the present disclosure. The method for manufacturing an electrochromic film includes steps S10 to S40, wherein steps S10 to S40 can be performed in sequence. In step S10, a film forming step is performed to form a film-like stacked layer, the film-like stacked layer includes a first conductive film material, a color-changing reduction layer, a solid electrolyte layer, a color-changing oxide layer, and a second conductive film material stacked in sequence, and the material of the color-changing reduction layer includes tungsten oxide. In step S20, a cutting step is performed, including removing the second conductive film material, the color-changing oxide layer and the solid electrolyte layer on the first side of the film-like stack, so that the color-changing reduction layer on the first side is exposed. In step S30, a cleaning step is performed, including using a first solution to clean the exposed color-changing reduction layer, so that part of the first conductive film material is exposed, wherein the first solution includes sodium hydroxide, hydrogen peroxide and water. In step S40, a coating step is performed, including forming a first electrode on the surface of the exposed first conductive film material. In the following description, each of the above steps will be described in detail through Figures 2 to 5C, wherein Figure 2 is a schematic diagram of the process of the film-like stack according to some embodiments of the present disclosure, Figure 3A is a three-dimensional schematic diagram of the film-like stack 100 according to some embodiments of the present disclosure, Figure 3B is a schematic diagram of the cross-section of the film-like stack 100 of Figure 3A taken along the line segment A-A', Figures 4A, 4B and 4C are schematic diagrams of the cross-section of the electrochromic film 1000 according to some embodiments of the present disclosure at different stages during the process, and Figures 5A to 5C are schematic diagrams of the electrochromic film 1000 according to some embodiments of the present disclosure in different embodiments during the process.

First, in step S10, a film forming step is performed to form a film-shaped stack 100. Specifically, the film forming step may include steps S11 to S16. First, in step S11, a color-changing reduction layer 120 is formed on the first conductive film material 110. In some embodiments, the color-changing reduction layer 120 may be formed on the surface 111 of the first conductive film material 110 that is continuously supplied through a roll-to-roll process. In some embodiments, the first conductive film material 110 may include a substrate 115 and an indium tin oxide conductive film 117 disposed on a surface 116 of the substrate 115, wherein the material of the substrate 115 may include polyethylene terephthalate, and the thickness H1 of the substrate 115 may be between 38 microns and 188 microns, preferably between 75 microns and 125 microns, and more preferably between 100 microns and 125 microns, so that the first conductive film material 110 has a certain bearing capacity and good flexibility, which is conducive to integration into the roll-to-roll process. In some embodiments, the surface resistance of the indium tin oxide conductive film 117 may be between 5Ω/□ and 50Ω/□, so that the electrochromic film 1000 has suitable electrical specifications.

In some embodiments, the color-changing reduction layer 120 can be formed by evaporation or sputtering, so that the color-changing reduction layer 120 is disposed on the surface 118 of the indium tin oxide conductive film 117 facing away from the substrate 115. The color-changing reduction layer 120 formed by evaporation or sputtering can have good material density and material distribution uniformity, so it is not easy to fall off or crack, and stably provides ions when the electric field changes. It is to be noted that, compared with the use of spin coating, electroplating, wet coating and other processes, the use of evaporation or sputtering to form the color-changing reduction layer 120 has its advantages. Specifically, the use of spin coating, electroplating, wet coating and other processes easily leads to poor slurry adhesion, which makes the color-changing reduction layer 120 easy to fall off, resulting in the inability to change color or reducing the service life. In some embodiments, the material of the color-changing reduction layer 120 may include tungsten oxide. In some embodiments, the thickness H2 of the color-changing reduction layer 120 may be between 50 nm and 800 nm, preferably between 100 nm and 600 nm, and more preferably between 100 nm and 400 nm, so that the color-changing reduction layer 120 can stably provide ions (stably produce color changes) when the electric field changes and has good flexibility and is not too thick, thereby facilitating integration into the roll-to-roll process.

Next, in step S12, a color-changing oxide layer 140 is formed on the second conductive film material 130. In some embodiments, the color-changing oxide layer 140 can be formed on the surface 131 of the continuously supplied second conductive film material 130 through a roll-to-roll process. In some embodiments, the second conductive film material 130 can include a substrate 135 and an indium tin oxide conductive film 137 disposed on a surface 136 of the substrate 135, wherein the material of the substrate 135 can include polyethylene terephthalate, and the thickness H3 of the substrate 135 can be between 38 microns and 188 microns, preferably between 75 microns and 125 microns, and more preferably between 100 microns and 125 microns, so that the second conductive film material 130 has both a certain bearing capacity and good flexibility, thereby facilitating integration into the roll-to-roll process. In some embodiments, the surface resistance of the indium tin oxide conductive film 137 can be between 5Ω/□ and 50Ω/□, so that the electrochromic film 1000 has suitable electrical specifications. It is worth noting that the same material, thickness and specifications are used to form the first conductive film material 110 and the second conductive film material 130, so that the electrochromic film 1000 has better performance in terms of structural stability and electrical stability.

In some embodiments, the color-changing oxide layer 140 can be formed by evaporation or sputtering, so that the color-changing oxide layer 140 is disposed on the surface 138 of the indium tin oxide conductive film 137 facing away from the substrate 135. The color-changing oxide layer 140 formed by evaporation or sputtering can have good material density and uniform material distribution, and is not easy to fall off or crack, and can stably provide ions when the electric field changes. It should be noted that compared with using spin coating, electroplating, wet coating and other processes, using evaporation or sputtering to form the color-changing oxide layer 140 has its advantages. Specifically, using spin coating, electroplating, wet coating and other processes can easily lead to poor slurry adhesion, which can easily cause the color-changing reduction layer 120 to fall off, resulting in failure to change color or reduced service life. In some embodiments, the material of the color-changing oxide layer 140 may include nickel oxide. In some embodiments, the thickness H4 of the color-changing oxide layer 140 may be between 100 nanometers and 800 nanometers, preferably between 200 nanometers and 700 nanometers, and more preferably between 400 nanometers and 600 nanometers, so that the color-changing oxide layer 140 can stably accept ions (stably produce color changes) when the electric field changes, and has good flexibility and is not too thick, thereby facilitating integration into a roll-to-roll process. In some embodiments, since the reaction speeds of the color-changing reduction layer 120 and the color-changing oxide layer 140 are different, the thickness H4 of the color-changing oxide layer 140 can be adjusted to be at least 100 nanometers greater than the thickness H2 of the color-changing reduction layer 120, so that the color-changing oxide layer 140 and the color-changing reduction layer 120 can be matched to achieve better electrochromic performance.

Then, in step S13, the color-changing reduction layer 120 is continuously supplied and the ion-conducting gel G is formed on the color-changing reduction layer 120. More specifically, the first conductive film material 110 equipped with the color-changing reduction layer 120 can be transported in a roll-to-roll process by the rotation of the first conveying wheel R1, so that the first conductive film material 110 equipped with the color-changing reduction layer 120 can be continuously and uninterruptedly supplied. At the same time, the ion-conducting gel G is provided to the first conveying wheel R1, so that the surface 121 of the color-changing reduction layer 120 opposite to the first conductive film material 110 can receive the ion-conducting gel G provided by the sprayer M. In some embodiments, the coating speed of the sprayer M may be between 1 m/min and 20 m/min, that is, the ion conductive colloid G may be coated on the surface 121 of the continuously supplied color-changing reduction layer 120 at a speed of 1 m/min to 20 m/min, so that the ion conductive colloid G may be arranged on the surface 121 of the color-changing reduction layer 120 in an appropriate amount and at an appropriate density. Specifically, if the coating speed of the spray coating machine M is greater than 20 m/min, the content of the ion conductive colloid G carried per unit area on the surface 121 of the color-changing reduction layer 120 may be too low, that is, the distribution of the ion conductive colloid G on the surface 121 of the color-changing reduction layer 120 is too sparse, and the color-changing reduction layer 120 cannot be closely bonded to the subsequent color-changing reduction layer 120. The reduction layer 120 and the color-changing oxidation layer 140; if the coating speed of the sprayer M is less than 1 meter/minute, the surface 121 of the color-changing reduction layer 120 may carry too much ion-conducting gel G per unit area, which not only easily causes glue overflow during the subsequent pressing, but also causes unnecessary waste of materials. In a preferred embodiment, the coating speed of the sprayer M can be between 2 meters/minute and 6 meters/minute, thereby achieving a better bonding effect.

On the other hand, controlling the coating speed of the spray coating machine M within the above range can also help control the thickness H5 of the ion conductive gel G formed on the surface 121 of the color-changing reduction layer 120, so that the thickness H5 of the ion conductive gel G can be controlled between 10 microns and 100 microns. This can not only improve the stability of the film material (for example, the first conductive film material 110 equipped with the ion conductive gel G and the color-changing reduction layer 120) during transportation, but also avoid the overflow of the glue during the subsequent pressing period, and ensure that the solid electrolyte layer 150 formed by the ion conductive gel G after subsequent curing has good ionic conductivity. Specifically, if the thickness H5 of the ion conductive gel G is less than 10 microns, a break may be formed during subsequent pressing, resulting in a discontinuous distribution of the formed solid electrolyte layer 150, and thus failing to provide good ion conductivity; and if the thickness H5 of the ion conductive gel G is greater than 100 microns, subsequent pressing may be difficult, and the thicker the thickness H5 of the ion conductive gel G, the slower the electron conduction efficiency, resulting in a slower color change speed, and not conducive to forming the "thin film" electrochromic film 1000 emphasized in the present disclosure. In a preferred embodiment, the thickness H5 of the ion conductive gel G can be further controlled to be between 20 microns and 50 microns, thereby better achieving the above effect. In some embodiments, the thickness H5 of the ion conductive colloid G formed on the surface 121 of the color-changing reduction layer 120 is the thickness H5 of the solid electrolyte layer 150 after curing.

It is worth noting that the present disclosure further uses a specially improved ion conductive gel G to integrate the coating of the ion conductive gel G into the roll-to-roll process, and the ion conductive gel G can be finally cured into a solid electrolyte layer 150, so that the final electrochromic film 1000 can omit the configuration of the frame glue (this part will be described in more detail below), so that the electrochromic film 1000 can be configured according to objects of different shapes and curvatures, thereby greatly improving the applicability and installation convenience of the electrochromic film 1000, so that the electrochromic film 1000 can be applied in a variety of fields.

In detail, the preparation method of the ion conductive gel G may include the following steps. First, lithium perchlorate (LiClO ₄ ) is added to polycarbonate (PC) and stirred for 8 to 12 hours to uniformly disperse and mix, thereby forming an electrolyte mixture. Then, the electrolyte mixture is added to the UV curable glue and stirred for 8 to 12 hours with a homogenizer to uniformly disperse and mix, and then a photoinitiator is added and stirred for 0.5 to 2 hours to form the ion conductive gel G. In some embodiments, the content of the electrolyte mixture may be between 30 parts by weight and 40 parts by weight, the content of the UV-curable adhesive may be between 60 parts by weight and 70 parts by weight, and the content of lithium perchlorate may be between 1 wt% and 15 wt% based on the total weight of the electrolyte mixture. In detail, if the content of the electrolyte mixture is greater than 40 parts by weight (or the content of the UV-curable adhesive is less than 60 parts by weight), and the content of lithium perchlorate is greater than 15 wt%, it may cause the lithium salt (lithium perchlorate) in the ion-conducting gel G to be too much, making it difficult to disperse evenly and easily aggregate into lumps (clumps, precipitation), and the content of the UV-curable adhesive may be too little, causing the local block in the ion-conducting gel G to fail to fully cure, resulting in glue overflow (or If the content of the electrolyte mixture is less than 30 parts by weight (or the content of the UV-curable adhesive is greater than 70 parts by weight), and the content of lithium perchlorate is less than 1wt%, the lithium salt (lithium perchlorate) in the ion conductive gel G may be too little to provide sufficient ion conductivity, and the UV-curable adhesive may not be able to fully cure quickly in the dynamic roll-to-roll process due to the excessive content, and there is also the risk of glue overflow (or glue leakage). In a preferred embodiment, the content of lithium perchlorate is between 4wt% and 10wt% based on the total weight of the electrolyte mixture to better achieve the above effect.

In some embodiments, the UV-curable adhesive may include an acrylic resin (or an acrylic pressure-sensitive resin). For example, the acrylic (pressure-sensitive) resin may be polymethyl methacrylate, polyurethane acrylate, or epoxy acrylate. The above-mentioned acrylic resin UV-curable adhesive can be rapidly cured within a specific UV wavelength range, thereby facilitating the integration of the curing process into a roll-to-roll process and avoiding damage to other layers in the electrochromic film 1000 (e.g., the color-changing reduction layer 120 and the color-changing oxidation layer 140) due to excessive energy provided by the curing or due to excessively long curing time, as will be described below. As previously described, the ion-conducting gel G may include an appropriate amount of a photoinitiator so that the ion-conducting gel G reacts rapidly and cures after being irradiated with UV light. Specifically, the optional photoinitiator disclosed in the present invention includes acylphosphine oxide materials (models: Irgacure® TPO, Irgacure® 819), and the content of the photoinitiator can be between 0.5wt% and 2.5wt% based on the total weight of the electrolyte mixture to achieve the best curing effect and avoid the photoinitiator residue from further decomposing other components in the cured solid electrolyte layer 150 and causing degradation of other components, thereby avoiding the rapid loss of ionic conductivity of the solid electrolyte layer 150 over time. Specifically, if the content of the photoinitiator is less than 0.5wt%, the ion conductive gel G may not be completely cured; and if the content of the photoinitiator is greater than 2.5wt%, the photoinitiator may remain in the solid electrolyte layer 150 due to incomplete consumption.

On the other hand, the viscosity of the ion conductive gel G is important for whether the solid electrolyte layer 150 can be stably disposed in the electrochromic film 1000 through a roll-to-roll process, and is also important for whether the electrolyte in the solid electrolyte layer 150 can be uniformly dispersed to achieve good ionic conductivity. In detail, the viscosity of the ion conductive gel G can affect its fluidity, viscosity and the dispersion of the ion salt therein. If the viscosity of the ion conductive gel G is too high, the fluidity of the ion conductive gel G may be too low and the viscosity may be too high. It is easy to accumulate at the nozzle of the spray coating machine M and is not easy to spread on the supporting surface (for example, the surface 121 of the color-changing reduction layer 120). It is too late to be evenly dispersed before the pressing step in the dynamic roll-to-roll process, resulting in the final solid electrolyte layer being formed. 150 cannot have a uniform thickness, thereby affecting the ionic conductivity of the solid electrolyte layer 150, and easily causing the lithium salt in the ion conductive colloid G to be unevenly dispersed, easily agglomerated or deposited; and if the viscosity of the ion conductive colloid G is too low, it may cause the fluidity of the ion conductive colloid G to be too high and the viscosity to be too low, which is not conducive to stably configuring it on the supporting surface (for example, the surface 121 of the color-changing reduction layer 120) in the dynamic roll-to-roll process, and it is not suitable as a colloid with a certain degree of adhesion. Based on the above, the present disclosure can control the viscosity of the ion conductive gel G within the range of 200 cps to 10000 cps within the processing temperature range of the roll-to-roll process (between 15° C. and 70° C.), so as to facilitate the overall coating of the ion conductive gel G in the roll-to-roll process. In a preferred embodiment, the viscosity of the ion conductive gel G can be further controlled within the processing range of 25° C. to 40° C., thereby better achieving the above effects and more stably maintaining the overall quality of the rolled electrochromic film 1000. It is to be noted that the viscosity of the ion conductive gel G is measured using a Brookfield (model: DV-E) viscometer. In some embodiments, a thermostat (not shown) can be used to contain the ion conductive gel G to be coated to ensure that the ion conductive gel G maintains a suitable viscosity during the coating period. In other words, the temperature of the thermostat can be controlled between 15°C and 70°C, preferably between 25°C and 40°C.

In some embodiments, in step S13, the ion conductive colloid G can also be selectively formed on the surface 141 of the continuously supplied color-changing oxide layer 140 opposite to the second conductive film material 130. In other words, the ion conductive colloid G can be selectively formed on the surface 121 of the continuously supplied color-changing reduction layer 120, or formed on the surface 141 of the continuously supplied color-changing oxide layer 140 according to actual process conditions.

Next, in step S14, the second conductive film material 130 provided with the color-changing oxide layer 140 is pressed onto the ion-conducting colloid G which is continuously supplied and arranged on the surface 121 of the color-changing reduction layer 120, so that the color-changing oxide layer 140 is located between the second conductive film material 130 and the ion-conducting colloid G. Specifically, the second conductive film material 130 provided with the color-changing oxide layer 140 can be transported in the roll-to-roll process by the rotation of the second conveying wheel R2, so as to transport the second conductive film material 130 provided with the color-changing oxide layer 140 to between the first pressing wheel P1 and the second pressing wheel P2, and at the same time, the first conductive film material 110 provided with the ion conductive gel G and the color-changing reduction layer 120 can be transported by the rotation of the first conveying wheel R1. Transported between the first pressing wheel P1 and the second pressing wheel P2, wherein the first pressing wheel P1 and the second pressing wheel P2 are configured to press the second conductive film material 130 provided with the color-changing oxide layer 140 onto the continuously supplied ion-conductive gel G, and the first pressing wheel P1 and the second pressing wheel P2 have opposite rotation directions (for example, the first pressing wheel P1 rotates clockwise, and the second pressing wheel P2 rotates counterclockwise).

In some embodiments, the distance d between the first pressing wheel P1 and the second pressing wheel P2 may be between 100 μm and 500 μm, that is, the distance d may be 85% to 105% of the overall thickness of the electrochromic film 1000 (or film-like laminate 100) expected to be obtained in the present disclosure, thereby providing good pressing strength. Specifically, if the distance d between the first pressing wheel P1 and the second pressing wheel P2 is less than 100 microns (i.e., less than 85% of the overall thickness of the electrochromic film 1000 or the film-like laminate 100), it may cause seepage, thereby affecting the configuration state of the ion-conducting gel G; and if the distance d between the first pressing wheel P1 and the second pressing wheel P2 is greater than 500 microns (i.e., greater than 105% of the overall thickness of the electrochromic film 1000 or the film-like laminate 100), it may cause the layers to fail to be tightly bonded, thereby affecting the structural stability of the electrochromic film 1000. In some embodiments, the speed ratio of the first pressing wheel P1 and the second pressing wheel P2 may be between 1.5:1.0 and 1.0:1.5 (for example, 1:1), thereby controlling the tension of each layer so that the final electrochromic film 1000 has good flatness. In some embodiments, the wheel temperature of the first pressing wheel P1 and the second pressing wheel P2 may be between 15°C and 70°C, and preferably between 25°C and 40°C, to ensure that the ion conductive gel G still has good leveling during the conveying process. In some embodiments, the first pressing wheel P1 and the second pressing wheel P2 may be driven by different and independently operated motors.

Then, in step S15, the ion conductive gel G is cured to form a solid electrolyte layer 150. Specifically, after each layer (the first conductive film material 110, the color-changing reduction layer 120, the ion conductive gel G, the color-changing oxidation layer 140, and the second conductive film material 130) is pressed by the first pressing wheel P1 and the second pressing wheel P2, each layer can pass through an ultraviolet light source U so that each layer is irradiated with ultraviolet light during the transport of the roll-to-roll process. In other words, ultraviolet light can be used to irradiate the ion conductive gel G sandwiched between the color-changing reduction layer 120 and the color-changing oxidation layer 140, so that the ion conductive gel G is cured to form a solid electrolyte layer 150, and the color-changing reduction layer 120 and the color-changing oxidation layer 140 are tightly and firmly bonded. As mentioned above, the present disclosure uses an acrylic resin that can be quickly cured within a specific ultraviolet light wavelength range as the ultraviolet light curing glue, and the specific ultraviolet light wavelength range can avoid damaging other layers in the electrochromic film 1000. Specifically, the wavelength of the ultraviolet light can be between 365 nanometers and 395 nanometers. Since this wavelength range is narrow, it can provide more concentrated energy, so that the ion conductive gel G can be thoroughly cured even if it needs to pass through the ultraviolet light source U quickly in the roll-to-roll process (for example, passing through the ultraviolet light source U at a conveying speed of 1 meter/minute to 20 meters/minute). In some embodiments, the length of the ultraviolet light irradiation range (the length parallel to the conveying direction) can be between 1 meter and 3 meters, and the width (the width perpendicular to the conveying direction, the width) can be between 300 mm and 1600 mm, so as to ensure that all the ion conductive gel G is indeed irradiated by ultraviolet light and cured to form a solid electrolyte layer 150.

After at least performing the above steps S11 to S15, the film-like laminate 100 can be rolled up to form a film-like laminate 100. In some embodiments, the rolled film-like laminate 100 can be further cut to form an electrochromic film 1000 of a desired size and shape according to actual application requirements. Please refer to FIG. 3A and FIG. 3B at the same time. The cut film-like laminate 100 includes a first conductive film material 110, a color-changing reduction layer 120, a solid electrolyte layer 150, a color-changing oxide layer 140, and a second conductive film material 130. The color-changing reduction layer 120 is disposed on the first conductive film material 110, the solid electrolyte layer 150 is disposed on the color-changing reduction layer 120, the color-changing oxide layer 140 is disposed on the solid electrolyte layer 150, and the second conductive film material 130 is disposed on the color-changing oxide layer 140. In the film-shaped stack 100, the color-changing reduction layer 120 is configured to produce an oxidation-reduction reaction with the color-changing oxide layer 140 when the electrochromic film 1000 undergoes an electric field change. When the ions in the color-changing reduction layer 120 move to the color-changing oxide layer 140, the color-changing reduction layer 120 produces a color change, and the color-changing oxide layer 140 undergoes an oxidation reaction due to receiving the ions in the color-changing reduction layer 120, and also produces a color change. For example, the color-changing oxide layer 140 contains tungsten oxide, and when the electric field of the electrochromic film 1000 is not changed, the color-changing oxide layer 140 is transparent. When the electric field of the electrochromic film 1000 is changed, the color-changing oxide layer 140 turns blue, so that the light transmittance of the electrochromic film 1000 changes.

It is worth noting that each layer in the film-like stack 100 formed by the cutting step has substantially flat side walls S, and through the arrangement of the solid electrolyte layer 150, the film-like stack 100 disclosed herein and the electrochromic film 1000 formed subsequently do not need to be additionally provided with a frame on the side walls S to prevent the solid electrolyte layer 150 from being deformed. The ion-conducting material flows out, and through the design of the above-mentioned roll-to-roll process, the color-changing reduction layer 120 and the color-changing oxide layer 140 can be tightly bonded to each other, so there is no need to additionally set a frame glue (frame) on the side wall S of the film-like stack 100 and the subsequently formed electrochromic film 1000 to prevent the color-changing reduction layer 120 and the color-changing oxide layer 140 from peeling off. In other words, the electrochromic film 1000 finally formed in the present disclosure does not have a frame glue disposed on and contacting at least one side of each of the first conductive film material 110, the color-changing reduction layer 120, the solid electrolyte layer 150, the color-changing oxide layer 140, and the second conductive film material 130, so the side wall S of the electrochromic film 1000 is exposed to the external environment. In detail, the frame materials used in conventional electrochromic devices may generally include acrylic resin, epoxy resin, or a combination thereof (e.g., frame materials used in the One Drop Filling (ODF) process, Seal frame materials (manufacturers: Sekisui Chemical, Mitsui Chemicals, Kyoritsu Kyoritsu, and Nippon Kayaku)), while the electrochromic film 1000 disclosed herein does not have a frame material including the above materials.

In some embodiments, the film-like laminate 100 may further include a hardening layer 160. The hardening layer 160 may protect the layers from scratches or abrasions, thereby extending the service life of the electrochromic film 1000. In some embodiments, the material of the hardening layer 160 may include a resin mixture to ensure that the film-like laminate 100 is flexible and thin. In some embodiments, the stacking of the hardening layer 160 may also be integrated into the roll-to-roll process, thereby facilitating the improvement of process convenience and productivity.

Then, please refer to FIG. 4A , in step S20, a cutting step is performed, including removing the second conductive film material 130, the color-changing oxide layer 140, and the solid electrolyte layer 150 on the first side S1 of the film-like stack 100, so that the color-changing reduction layer 120 on the first side S1 is exposed. In detail, the area where the electrode is to be set (electrode area) can be reserved before the cutting step, and the second conductive film material 130, the color-changing oxide layer 140, the solid electrolyte layer 150 located in the electrode area and the hardening layer 160 contacting the surface of the second conductive film material 130 are removed through the cutting step. In some embodiments, the cutting step can be performed by using cutting equipment (means) such as a _CO2 laser machine, a stamping machine, a dimming film electrode knife, etc. In some embodiments, the electrode region of the film-like stack 100 can be cut before the film-like stack 100 is cut into a suitable size (before the cutting step is performed), for example, the cutting step is integrated into the roll-to-roll process, and the film-like stack 100 is transported in the roll-to-roll process by the rotation of the conveyor wheel, so that the film-like stack 100 is continuously supplied to the cutter for cutting, so as to increase the speed of the cutting step. After the second conductive film material 130, the color-changing oxide layer 140, the solid electrolyte layer 150 and the hardening layer 160 in contact with the surface of the second conductive film material 130 located in the electrode area are removed, the color-changing reduction layer 120 located in the electrode area can be exposed, and the side walls of the color-changing reduction layer 120 and the first conductive film material 110 will protrude from the side walls of the second conductive film material 130, the color-changing oxide layer 140 and the solid electrolyte layer 150. In some embodiments, the cutting step cannot completely remove the solid electrolyte layer 150 located in the electrode area. For example, the cutting step may only reduce the thickness H5 of the solid electrolyte layer 150, or remove part of the solid electrolyte layer 150 to expose part of the color-changing reduction layer 120 located in the electrode area.

In addition, in step S20, the cutting step further includes removing the first conductive film material 110, the color-changing reduction layer 120, the solid electrolyte layer 150 and the hardening layer 160 contacting the surface of the first conductive film material 110 on the second side S2 of the film-like stack 100, so that the color-changing oxide layer 140 of the second side S2 is exposed. In detail, before the cutting step is performed, the area where the electrode is to be set (electrode area) is reserved, and the first conductive film material 110, the color-changing reduction layer 120, the solid electrolyte layer 150 and the hardening layer 160 contacting the surface of the first conductive film material 110 are removed through the cutting step. The specific removal method is as described in the previous paragraph and will not be repeated here. After the first conductive film material 110, the color-changing reduction layer 120 and the solid electrolyte layer 150 located in the electrode area are removed, the color-changing oxide layer 140 located in the electrode area can be exposed, and the side walls of the color-changing oxide layer 140 and the second conductive film material 130 will protrude from the side walls of the first conductive film material 110, the color-changing reduction layer 120 and the solid electrolyte layer 150. In some embodiments, the cutting step cannot completely remove the solid electrolyte layer 150 located in the electrode area. For example, the cutting step may only reduce the thickness H5 of the solid electrolyte layer 150, or remove part of the solid electrolyte layer 150 to expose part of the discoloration oxide layer 140 located in the electrode area. After completing this step, the first electrode area A1 and the second electrode area A2 can be defined on the first side S1 and the second side S2 of the film-like stack 100, respectively, in preparation for setting the positive electrode and the negative electrode in the subsequent process.

Next, referring to FIG. 4B , in step S30, a cleaning step is performed, including using a first solution and a second solution to clean the exposed color-changing reduction layer 120 and the color-changing oxidation layer 140. For the color-changing reduction layer 120, when the material of the color-changing reduction layer 120 includes tungsten oxide, the first solution used may include sodium hydroxide, hydrogen peroxide and water. In more detail, sodium hydroxide can react with tungsten oxide, causing tungsten oxide to fall off the surface 118 of the indium tin oxide conductive film 117 of the first conductive film material 110, while hydrogen peroxide can maintain a stable etching (removal) rate, and water can properly adjust the concentration of sodium oxide and hydrogen peroxide, and help to remove the residues after the reaction is completed. In some embodiments, in the first solution, the content of sodium hydroxide is between 15 parts by weight and 40 parts by weight (preferably between 25 parts by weight and 35 parts by weight), and the content of hydrogen peroxide is between 2 parts by weight and 10 parts by weight (preferably between 4 parts by weight and 8 parts by weight) to achieve an excellent removal effect. In detail, if the content (ratio) of sodium hydroxide is too high and the content (ratio) of hydrogen peroxide is too low, sodium hydroxide may remain on the surface 118 of the indium tin oxide conductive film 117, resulting in an increase in the cleaning time, and the etching rate may be reduced due to the complete consumption of hydrogen peroxide during the reaction period; if the content of sodium hydroxide is too low and the content of hydrogen peroxide is too high, the tungsten oxide may not react completely and cannot be completely removed, and the sodium hydroxide may be continuously consumed during the reaction period, resulting in excess hydrogen peroxide, which may affect (decrease) the pH value of the first solution and affect the cleaning effect. In other words, through the synergistic effect of sodium hydroxide, hydrogen peroxide and water, the material of the color-changing reduction layer 120 can be completely removed in a short time, so that the first conductive film material 110 located under the removed color-changing reduction layer 120 is exposed.

In some embodiments, before or during the cleaning step using the first solution, the pH value of the first solution may be adjusted (maintained) to between 8.0 and 10.0, so that sodium hydroxide, hydrogen peroxide, and water can be stably coordinated with each other during etching to maintain the reactivity and reaction rate of the first solution. In some embodiments, after the cleaning step using the first solution, the surface 111 of the first conductive film 110 may be cleaned with 75% ethanol to ensure that all residues are removed from the surface 111 of the first conductive film 110. In some embodiments, if the solid electrolyte layer 150 in the first electrode region A1 is not completely removed in the previous step (cutting step), the solid electrolyte layer 150 can be completely removed using acetone or 75% ethanol before the cleaning step to enhance the reaction effect between the first solution and the color-changing reduction layer 120. In other words, in the present disclosure, the solid electrolyte layer 150 formed by the ion-conducting colloid G can be simply removed by acetone or 75% ethanol, thereby enhancing the simplicity of the cleaning step. In some embodiments, the cleaning step can be performed by wiping, for example, using the first solution to wipe back and forth multiple times (e.g., 5 to 20 times) on the surface 121 of the color-changing reduction layer 120 in the first electrode region A1 to achieve an excellent cleaning effect. It can be seen that the first solution used in the present disclosure can quickly and easily remove the color-changing reduction layer 120. The present disclosure can confirm that the resistance of the first conductive film material 110 is less than 500Ω by using a four-point probe to confirm that the color-changing reduction layer 120 located in the first electrode area A1 is completely removed.

On the other hand, in step S30, for the color-changing oxide layer 140, when the material of the color-changing oxide layer 140 includes nickel oxide, the second solution used may include nitric acid, citric acid, hydrogen peroxide and water. In more detail, nitric acid can react with nickel oxide to cause nickel oxide to fall off from the surface 138 of the indium tin oxide conductive film 137 of the second conductive film material 130, citric acid can increase the etching (removal) rate, and hydrogen peroxide can maintain a stable etching rate, and water can appropriately adjust the concentrations of nitric acid, citric acid and hydrogen peroxide, and help to take away the residues after the reaction is completed. In some embodiments, in the second solution, the content of nitric acid is between 15 parts by weight and 40 parts by weight (preferably between 30 parts by weight and 40 parts by weight), the content of citric acid is between 0.5 parts by weight and 10 parts by weight (preferably between 4 parts by weight and 6 parts by weight), and the content of hydrogen peroxide is between 1 part by weight and 10 parts by weight (preferably between 3 parts by weight and 8 parts by weight) to achieve an excellent cleaning effect. In detail, if the content (ratio) of nitric acid is too high, nitric acid residues may remain on the surface 118 of the indium tin oxide conductive film 117, which may increase the cleaning time. If the content of nitric acid is too low, nickel oxide may not react completely and cannot be completely removed. If the content (ratio) of citric acid is too high, the etching rate may be too high, which may easily erode the surface 118 of the indium tin oxide conductive film 117, resulting in indium oxide. The tin conductive film 117 is dissolved or peeled off. If the content of citric acid is too low, the etching rate may be reduced. If the content (ratio) of hydrogen peroxide is too low, the etching rate may be reduced due to insufficient hydrogen peroxide during the reaction period. If the content of hydrogen peroxide is too high, the sodium hydroxide may be continuously consumed during the reaction period, resulting in excess hydrogen peroxide, which may affect the pH value of the second solution and affect the cleaning effect. In other words, through the synergistic effect of nitric acid, citric acid, hydrogen peroxide and water, the material of the color-changing oxide layer 140 can be completely removed in a short time, so that the second conductive film material 130 located under the removed color-changing oxide layer 140 is exposed.

In some embodiments, before or during the cleaning step using the second solution, the pH value of the second solution may be adjusted (maintained) to be between 1.0 and 3.0, so that nitric acid, citric acid, hydrogen peroxide, and water can be stably coordinated with each other during etching to maintain the reactivity and reaction rate of the second solution. In some embodiments, after the cleaning step using the second solution, the surface 131 of the second conductive film material 130 may be cleaned with 75% ethanol to ensure that all residues are removed from the surface 131 of the second conductive film material 130. In some embodiments, if the solid electrolyte layer 150 in the second electrode region A2 is not completely removed in the previous step (cutting step), the solid electrolyte layer 150 can be completely removed using acetone or 75% ethanol before the cleaning step to enhance the reaction effect between the second solution and the color-changing oxide layer 140. In some embodiments, the cleaning step can be performed by wiping, for example, using the second solution to wipe back and forth multiple times (e.g., 5 to 20 times) on the surface 141 of the color-changing oxide layer 140 in the second electrode region A2 to achieve an excellent cleaning effect. It can be seen that the second solution used in the present disclosure can quickly and easily remove the color-changing oxide layer 140. The present disclosure can confirm that the resistance of the second conductive film material 130 is less than 500Ω by using a four-point probe to confirm that the discolored oxide layer 140 located in the second electrode region A2 is completely removed.

It should be understood that the first electrode region A1 and the second electrode region A2 located on the first side S1 and the second side S2 of the film-like stack 100 can be arranged in position according to the shape of the film-like stack 100 being cut (i.e., the final shape of the electrochromic film 1000). For example, please refer to Figures 5A to 5C, which show top views of the electrochromic film 1000 during the process (cutting step and cleaning step) in different embodiments according to some embodiments of the present disclosure. The embodiment of Figure 5A shows that the electrochromic film 1000 has a rectangular shape, and the first electrode region A1 and the second electrode region A2 are respectively located on opposite sides of the electrochromic film 1000. The embodiment of FIG. 5B shows that the electrochromic film 1000 has a square shape, and the first electrode region A1 and the second electrode region A2 are adjacent to each other and each has an "L" shape. The embodiment of FIG. 5C shows that the electrochromic film 1000 has an elliptical shape, and the first electrode region A1 and the second electrode region A2 are located on opposite sides of the electrochromic film 1000 and each has a "U" shape. In short, the first electrode region A1 and the second electrode region A2 can have various possible configurations and shapes, and are not limited to the embodiments disclosed herein.

Subsequently, referring to FIG. 4C , in step S40, a coating step is performed, including forming a first electrode E1 on the surface 111 of the exposed first conductive film material 110, and forming a second electrode E2 on the surface 131 of the exposed second conductive film material 130. Specifically, the first electrode E1 and the second electrode E2 can be the positive and negative electrodes of the electrochromic film 1000, respectively, and the first electrode E1 and the second electrode E2 can be, for example, conductive silver gel, flexible printed circuit (FPC) or conductive copper foil. The first electrode E1 formed by coating may be adjacent to the color-changing reduction layer 120 and have a gap SP between the color-changing reduction layer 120; and the second electrode E2 formed by coating may be adjacent to the color-changing oxide layer 140 and have a gap SP between the color-changing oxide layer 140. In some embodiments, the thickness H6 of the first electrode E1 may be increased by coating multiple times, so that the first electrode E1 is further adjacent to the side walls of the solid electrolyte layer 150 and the color-changing oxide layer 140, and the thickness H7 of the second electrode E2 may be increased by coating multiple times, so that the second electrode E2 is further adjacent to the side walls of the solid electrolyte layer 150 and the color-changing reduction layer 120. This ensures that the first electrode E1 and the second electrode E2 have high material density, thereby reducing the probability of electrical failure. In some embodiments, the top surface E1T of the first electrode E1 can be lower than the surface 131 of the second conductive film material 130, and the top surface E2T of the second electrode E2 can be lower than the surface 111 of the first conductive film material 110 to ensure that there is no electrical connection between the first electrode E1 and the second electrode E2.

Next, please continue to refer to FIG. 4C , the manufacturing method of the electrochromic film 1000 may further include step S50 . In step S50 , an edge sealing structure 170 may be formed in the gap SP. In more detail, the edge-sealing structure 170 located in the first electrode area A1 can fill the gap SP and extend to the side walls of the color-changing reduction layer 120, the solid electrolyte layer 150, the color-changing oxide layer 140, the second conductive film material 130 and the hardening layer 160, so as to reduce the probability of environmental factors such as moisture and dust invading the electrochromic film 1000; similarly, the edge-sealing structure 170 located in the second electrode area A2 can fill the gap SP and extend to the side walls of the color-changing oxide layer 140, the solid electrolyte layer 150, the color-changing reduction layer 120, the first conductive film material 110 and the hardening layer 160, so as to reduce the probability of environmental factors such as moisture and dust invading the electrochromic film 1000. In some embodiments, the edge sealing structure 170 may further extend to, cover, and contact the top surface E1T of the first electrode E1 and the top surface E2T of the second electrode E2, and not protrude from the outer side walls of the first electrode E1 and the second electrode E2, so as to enhance the structural stability of the edge sealing structure 170. In some embodiments, the edge sealing structure 170 may have a curved side wall C to withstand bending stress. In some embodiments, the material of the edge sealing structure 170 may include acrylic resin, epoxy resin, or a combination thereof, so as to have good barrier properties. In some embodiments, the edge sealing structure 170 can be formed by coating, and the slurry used can be irradiated with ultraviolet light with a wavelength of 365nm to 395nm, and the required time is 30 seconds to 60 seconds to cure, so that other layers in the electrochromic film 1000 will not be damaged, and the process is convenient. It is hoped that the edge sealing structure 170 disclosed in the present invention is not set to prevent the electrolyte from flowing out. More specifically, since the electrolyte used in the present invention is a solid electrolyte, even if the edge sealing structure 170 is not set, there will be no leakage or outflow of the electrolyte.

According to the above-mentioned implementation method of the present disclosure, the present disclosure not only improves the traditional plate-shaped electrochromic element with a hard material such as a glass substrate as a base layer to form an electrochromic film, but also integrates the manufacturing process of the electrochromic film into a roll-to-roll process through specific process improvements. In this way, a rolled and film-shaped electrochromic film can be obtained instead of the traditional plate-shaped (sheet) electrochromic element with a hard material such as a glass substrate as a base layer. Therefore, the electrochromic film can be directly cut into a suitable shape and size according to the design of the back end, so that the entire electrochromic film manufacturing method will not be limited by the final shape, size and curvature of the electrochromic film when it is used. On the other hand, the formation of electrochromic film through roll-to-roll process can not only improve production efficiency and yield, avoid exhaust gas or waste liquid emission, and improve storage and transportation convenience, but also can be produced in a smaller production base compared to the traditional glass process, greatly improving the process convenience and not limiting the production capacity. In addition, the rolled electrochromic film can be cut and the residual color-changing oxidation/reduction layer can be completely removed in a short time through the special process method (cleaning solution/method) disclosed in the present invention, which is not only conducive to the stable formation of electrodes in the electrochromic film, but also greatly improves the process convenience. In addition, the electrochromic film prepared by the manufacturing method disclosed herein can omit the configuration of the frame glue (frame), that is, there is no need to introduce additional frame glue to prevent the electrolyte in the electrochromic film from leaking out, thereby greatly improving the applicability and installation convenience of the electrochromic film, so that the electrochromic film can be applied to a variety of fields.

Although the present disclosure has been disclosed in the form of implementation as above, it is not intended to limit the present disclosure. Anyone familiar with this art can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the scope defined in the attached patent application.

S10~S50: Steps

Claims (9)

A method for manufacturing an electrochromic film comprises: performing a film forming step, comprising forming a film-like stack, wherein the film-like stack comprises a first conductive film material, a color-changing reduction layer, a solid electrolyte layer, a color-changing oxide layer and a second conductive film material stacked in sequence, and the material of the color-changing reduction layer comprises tungsten oxide; performing a cutting step, comprising: removing the second conductive film material, the color-changing oxide layer and the solid electrolyte layer on a first side of the film-like stack, so that the color-changing reduction layer on the first side is exposed. The first conductive film material, the color-changing reduction layer and the solid electrolyte layer on the second side of the film-like stack are removed to expose the color-changing oxide layer on the second side; a cleaning step is performed, including using a first solution to remove the exposed color-changing reduction layer to expose part of the first conductive film material, wherein the first solution includes sodium hydroxide, hydrogen peroxide and water; and a coating step is performed, including forming a first electrode on a surface of the exposed first conductive film material. The manufacturing method of the electrochromic film as described in claim 1, wherein the material of the color-changing oxide layer includes nickel oxide, and the cleaning step further includes: using a second solution to remove the exposed color-changing oxide layer to expose part of the second conductive film material, and the second solution includes nitric acid, citric acid, hydrogen peroxide and water. The method for manufacturing an electrochromic film as described in claim 2, wherein in the second solution, the content of nitric acid is between 15 parts by weight and 40 parts by weight, the content of citric acid is between 0.5 parts by weight and 10 parts by weight, and the content of hydrogen peroxide is between 1 part by weight and 10 parts by weight. The method for manufacturing the electrochromic film as described in claim 2 further includes: adjusting the pH value of the first solution so that the pH value of the first solution is between 8.0 and 10.0; and adjusting the pH value of the second solution so that the pH value of the second solution is between 1.0 and 3.0. The method for manufacturing an electrochromic film as described in claim 1, wherein in the first solution, the content of sodium hydroxide is between 15 parts by weight and 40 parts by weight, and the content of hydrogen peroxide is between 2 parts by weight and 10 parts by weight. The method for manufacturing an electrochromic film as described in claim 1, wherein in the cleaning step, the exposed color-changing reduction layer is cleaned by wiping. The method for manufacturing an electrochromic film as described in claim 1, wherein there is a gap between the first electrode formed in the coating step and the solid electrolyte layer. The method for manufacturing the electrochromic film as described in claim 7 further includes: forming a sealing structure in the gap, wherein the material of the sealing structure includes acrylic resin, epoxy resin or a combination thereof. The method for manufacturing an electrochromic film as described in claim 8, wherein the edge sealing structure covers a top surface of the first electrode.

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