Steady-state low-light-transmittance dimming film and dimming glass

Abstract

According to the technical scheme, the steady-state low-light-transmittance dimming film comprises a dimming film body and is characterized in that the dimming film body comprises a first transparent substrate, a first transparent conducting layer, an active layer, a second transparent conducting layer and a second transparent substrate which are sequentially arranged in a stacked mode, and the dark-state light transmittance of the dimming film body is smaller than or equal to 0.5%. The dimming glass can achieve the effect of steady-state low light transmittance, and has the characteristics of good light shielding and transmitting performance and good privacy, so that the application field of the dimming glass is expanded.

Description

Technical Field

[0001] This utility model relates to the field of dimming technology, and in particular to a steady-state low-transmittance dimming film and dimming glass. Background Technology

[0002] A dimming film is a light-controlling device, primarily consisting of a dimming active layer sandwiched between two transparent conductive films. Types of dimming films include suspended particle dimming films (SPD), polymer-dispersed liquid crystal dimming films (PDLC), and electrochromic dimming films. For suspended particle dimming films, polymer-dispersed liquid crystal dimming films, and electrochromic dimming films, when electricity is applied, the arrangement or state of the materials within the dimming film changes, thereby altering the film's light transmittance characteristics, such as switching from low to high transmittance, or vice versa. These dimming films, which achieve rapid on-off switching through the action of an electric field / current, offer advantages such as active control of light transmittance and energy saving. They can be used in smart windows, rearview mirrors, sunglasses, displays, etc., for spacecraft, high-speed trains, automobiles, and buildings.

[0003] Although dimming films have been successfully developed for many years, UV-curable dimming films with a stable dark state generally have high dark-state transmittance, exceeding 0.5%. This results in poor light-blocking performance, limiting their application areas. The main reason for this is that if the dark-state transmittance is too low during the manufacturing process, UV light will have difficulty penetrating the wet film during UV curing, leading to incomplete curing and severely impacting the film's performance.

[0004] It is evident that in previous technologies, UV-cured dimming films with a steady-state dark state have relatively high dark-state transmittance. Therefore, there is a need to invent a dimming film with even lower steady-state transmittance. Utility Model Content

[0005] To address the aforementioned problems, this utility model aims to provide a dimming film with low light transmittance in the dark state, thereby changing the issue of high light transmittance in the dark state of the dimming film.

[0006] The technical solution of this utility model is a steady-state low transmittance dimming film, including a dimming film body, characterized in that: the dimming film body includes a first transparent substrate, a first transparent conductive layer, an active layer, a second transparent conductive layer, and a second transparent substrate stacked in sequence, wherein the dark state transmittance of the dimming film body is ≤0.5%.

[0007] Preferably, the dark transmittance of the dimming film body is ≤0.3%.

[0008] Preferably, the light transmittance of the dimming film body is ≥5% in the bright state.

[0009] Preferably, the light transmittance of the dimming film body is ≥15% in the bright state.

[0010] Preferably, the light transmittance of the dimming film body is ≥20%.

[0011] Preferably, the active layer is selected from suspended particle active layer, polymer dispersed liquid crystal active layer, and electrochromic active layer.

[0012] Preferably, the first transparent conductive layer and the second transparent conductive layer are each independently selected from one of the following: ITO conductive layer, FZO conductive layer, IZO conductive layer, GZO conductive layer, AZO conductive layer, PEDOT conductive layer, nano-Ag wire conductive layer, conductive graphene, conductive polymer and nano-Cu wire conductive layer.

[0013] Preferably, the first transparent substrate and the second transparent substrate are transparent plastic sheets.

[0014] This utility model provides a steady-state low-transmittance dimming glass, characterized in that it includes: a first transparent glass, a second transparent glass; and the aforementioned steady-state low-transmittance dimming film disposed between the first transparent glass and the second transparent glass.

[0015] Preferably, a first interlayer is provided between the first transparent glass and the dimming film body, and / or a second interlayer is provided between the second transparent glass and the dimming film body.

[0016] Preferably, the materials of the first and second adhesive layers are selected from one of EVA film, TPU film, and PVB film.

[0017] Preferably, the first transparent glass and the second transparent glass are selected from inorganic glass or organic glass, respectively.

[0018] This invention effectively reduces the dark-state transmittance of the dimming film and improves its ability to block light transmission, thereby broadening the application areas of this type of dimming film. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the dimming film of this utility model;

[0020] Figure 2 This is a schematic diagram of a structure of the dimming glass of this utility model;

[0021] Wherein: 1—Dimming film body; 11—First transparent substrate; 12—First transparent conductive layer; 13—Active layer; 14—Second transparent conductive layer; 15—Second transparent substrate; 2—First transparent glass; 3—Second transparent glass; 4—First interlayer; 5—Second interlayer. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings.

[0023] In this utility model, the following terms have the meanings defined below.

[0024] The steady state of a dimming film, i.e., its light-transmitting state without an applied electric field / current, is generally characterized by a dark steady state for suspended particle dimming films and a bright steady state after an electric field is applied; while for electrochromic dimming films, the steady state is bright and the steady state is dark after an electric current is applied. However, there are also cases where the steady state of suspended particle dimming films and polymer-dispersed liquid crystal dimming films is bright and the steady state is dark after an electric field is applied, or where the steady state of electrochromic dimming films is dark and the steady state is bright after an electric current is applied.

[0025] The dark state of the dimming film is the state in which the light transmittance of the dimming film is at its lowest.

[0026] The bright state of the dimming film represents the state in which the light transmittance of the dimming film is at its maximum.

[0027] The transition state of a dimming film is the state in which the light transmittance of the dimming film is between the dark state and the bright state.

[0028] A transparent conductive film, a stack of a transparent substrate and a transparent conductive layer.

[0029] This utility model provides a steady-state low transmittance dimming film, including a dimming film body 1. The dimming film body 1 includes a first transparent substrate 11, a first transparent conductive layer 12, an active layer 13, a second transparent conductive layer 14, and a second transparent substrate 15 stacked sequentially. The dark state transmittance of the dimming film body 1 is ≤0.5%.

[0030] In the above scheme, the dark state transmittance of the dimming film body 1 is ≤0.3%.

[0031] Specifically, the light transmittance of the dimming film body 1 in the bright state is ≥5%.

[0032] Specifically, the light transmittance of the dimming film body 1 in the bright state is ≥15%.

[0033] Specifically, the light transmittance of the dimming film body 1 in the bright state is ≥20%.

[0034] Specifically, the active layer 13 is selected from suspended particle active layer, polymer dispersed liquid crystal active layer, and electrochromic active layer.

[0035] Specifically, the first transparent conductive layer 12 and the second transparent conductive layer 14 are each independently selected from one of the following: ITO conductive layer, FZO conductive layer, IZO conductive layer, GZO conductive layer, AZO conductive layer, PEDOT conductive layer, nano-Ag wire conductive layer, conductive graphene, conductive polymer and nano-Cu wire conductive layer.

[0036] Specifically, the first transparent substrate 11 and the second transparent substrate 15 are transparent plastic sheets.

[0037] This utility model provides a steady-state low-transmittance dimming glass, characterized in that it includes: a first transparent glass 2, a second transparent glass 3, and the aforementioned steady-state low-transmittance dimming film disposed between the first transparent glass 2 and the second transparent glass 3.

[0038] Specifically, a first interlayer 4 is provided between the first transparent glass 2 and the dimming film body 1, and / or a second interlayer 5 is provided between the second transparent glass 3 and the dimming film body 1.

[0039] Specifically, the materials of the first interlayer 4 and the second interlayer 5 are selected from one of EVA film, TPU film, and PVB film.

[0040] Specifically, the first transparent glass 2 and the second transparent glass 3 are respectively selected from inorganic glass or organic glass.

[0041] The preparation method of a steady-state low-transmittance dimming film includes the following steps:

[0042] Step a: Apply an active coating to the transparent conductive layer side of a transparent conductive film.

[0043] Step b, UV curing,

[0044] Step c: Apply the active layer coating again to the active layer side of the laminate obtained in step b.

[0045] Step d: UV curing.

[0046] Step e, repeat steps c to d.

[0047] Step f: On the active layer side of the laminate obtained in step e, cover it with a transparent conductive film, with the transparent conductive layer side facing the active layer.

[0048] The active layer coating is selected from suspended particle active layer coating, polymer dispersed liquid crystal active layer coating, and electrochromic active layer coating.

[0049] Furthermore, the coating methods in steps a and c are each independently selected from one of the following: doctor blade coating, spin coating, spray coating, anilox coating, comma coating, slot coating, gravure coating, smooth roller coating, curtain coating, reverse roller coating, knife roller coating, metering rod coating, groove coating, dip coating, and air knife coating.

[0050] Furthermore, the transparent conductive layer is selected from one of the following: ITO conductive layer, FZO conductive layer, IZO conductive layer, GZO conductive layer, AZO conductive layer, PEDOT conductive layer, nano-Ag wire conductive layer, conductive graphene, conductive polymer, and nano-Cu wire conductive layer.

[0051] In this invention, by employing the aforementioned layer-by-layer coating and UV curing method, the number of layer-by-layer coating and UV curing operations can be controlled according to the required dark-state transmittance of the dimming film. This allows for the preparation of dimming films with adjustable and controllable dark-state transmittance within a wide range. On the same production line, when producing dimming films with different dark-state transmittances, the process switching is simple; only the number of layer-by-layer coating and UV curing operations needs to be adjusted to prepare dimming films with different dark-state transmittances, resulting in significant economic benefits.

[0052] A method for preparing steady-state low-transmittance dimming glass includes: stacking the layers of steady-state low-transmittance dimming glass sequentially and then performing lamination to obtain dimming glass;

[0053] Specifically, the temperature of the lamination process is 90–130°C, and the pressure is 0.1–1.5 MPa.

[0054] In this invention, there are no special restrictions on the types of the first transparent glass 2 and the second transparent glass 3. They can be conventional transparent glass for dimming glass that is well known to those skilled in the art. They can be ordinary glass such as inorganic glass or organic glass, or functional glass such as UV blocking glass, IR blocking glass, Low-E glass, tempered glass or antibacterial glass, etc. They can also be selected from colored glass such as gray glass or brown glass.

[0055] In this invention, there are no special restrictions on the types of the first interlayer 4 and the second interlayer 5. They can be conventional interlayers for dimming glass that are well known to those skilled in the art. They can be EVA film, TPU film, PVB film, or functional films, such as UV-blocking EVA film, UV-blocking TPU film, UV-blocking PVB film, etc. They can also be films with a certain color, such as gray EVA film, gray TPU film, gray PVB film, etc.

[0056] In this invention, there are no special restrictions on the method of manufacturing the dimming glass. It can be any conventional lamination method for dimming glass in the field, such as lamination in a laminator, or lamination in a high-pressure autoclave or lamination box / furnace.

[0057] Finally, the dimming glass produced by this invention can be applied to glass products such as automotive windows, skylights, or glass curtain walls.

[0058] This invention calculates the curing rate of the dimming film based on FT-IR test results:

[0059] The FT-IR data of the active coating layer (before curing) and the active layer (after curing) were tested separately.

[0060] Curing rate % = (1 - (M1 / R1) / (M0 / R0)) * 100

[0061] M1 / R1 is the 1406 cm⁻¹ in the FT-IR spectrum of the active layer (after curing). -1 Peak area and 1740cm -1 The ratio of peak areas

[0062] M0 / R0 is the 1406 cm⁻¹ value in the FT-IR spectrum of the active coating layer (before curing). -1 The peak area is 1740 cm⁻¹ -1 The ratio of peak area.

[0063] A higher percentage of curing rate indicates a better curing effect.

[0064]

Example 1

[0065] The preparation steps of the steady-state low transmittance dimming film are as follows:

[0066] Step a: Prepare a suspended particle active layer coating according to the method in Example 5 of CN112882258A.

[0067] Step b: Using a doctor blade type automatic coating machine (MSK-AFA-III type, MTI Corporation), the suspended particle active layer coating prepared in step a is coated onto the ITO side of the ITO / PET transparent conductive film, controlling the coating thickness of the suspended particle active layer coating to be 20 μm.

[0068] Step c: Curing the wet film prepared in step b under a nitrogen atmosphere using a UV curing machine (Aventk X200-150) for 1 minute with a UV lamp power of 700 W / m. 2 ,

[0069] Step d is the same as step b, except that the suspended particle active layer coating prepared in step a is applied onto the active layer prepared in step c.

[0070] Step e, repeat step c, only using the wet film from step d.

[0071] Step f, repeat steps d to e, 2 times.

[0072] Step g, repeat step d.

[0073] In steps h and g, another ITO / PET transparent conductive film is placed over the wet film, with the ITO side in contact with the wet film.

[0074] Step i: Under a nitrogen atmosphere, cure the wet film prepared in step h using a UV curing machine (Aventk X200-150) for 1 min at a UV lamp power of 700 W / m. 2 That is, to obtain Figure 1 The test results for the dimming film shown are shown in Table 1.

[0075]

Example 2

[0076] Same as [Example 1], except for step f, repeat steps d to e once, and the test results are shown in Table 1.

[0077]

Example 3

[0078] The suspended particle dimming film prepared in Example 2, consisting of two ultra-white glass layers and two EVA interlayers, is processed according to... Figure 2 The structures were stacked in sequence and laminated in an autoclave at a temperature of 110℃, a relative pressure of 0.6MPa, and a time of 60 minutes to obtain the dimming glass. The test results are shown in Table 1.

[0079] Comparative Example 1

[0080] Same as [Example 1], except that the preparation steps of the dimming film are as follows:

[0081] Step a: Prepare a suspended particle active layer coating according to the method in Example 5 of CN112882258A.

[0082] Step b: Using a doctor blade type automatic coating machine (MSK-AFA-III type, MTI Corporation), the suspended particle active layer coating prepared in step a is coated onto the ITO side of the ITO / PET transparent conductive film, controlling the coating thickness of the suspended particle active layer coating to be 20 μm.

[0083] In step c, another ITO / PET transparent conductive film is placed over the wet film from step b, with the ITO side in contact with the wet film.

[0084] Step d: Under a nitrogen atmosphere, cure the wet film prepared in step c using a UV curing machine (Aventk X200-150) for 1 min at a UV lamp power of 700 W / m. 2 The test results are shown in Table 1.

[0085] Comparative Example 2

[0086] Same as [Comparative Example 1], except that step b controls the coating thickness of the suspended particle active layer coating to be 100 μm. The test results are shown in Table 1.

[0087] Table 1

[0088] Example Total coating thickness (μm) Dark state transmittance Bright state transmittance# Curing rate Example 1 100 0.05% 40.5% 99.8% Example 2 80 0.20% 41.8% 99.8% Example 3 not applicable 0.15% 39.7% not applicable Comparative Example 1 20 20.80% 71.8% 99.8% Comparative Example 2 100 0.06% 39.6% 56.7%

[0089] #Power supply: 110V RMS, 60Hz

[0090] As can be seen from the results in Table 1, the preparation method of this invention can produce a UV-curable dimming film with very low steady-state dark-state transmittance. Since the thickness of a single coating is thin, it has little impact on the penetration of UV light and can achieve the expected curing effect. Comparing Example 1 and Comparative Example 2, it can be seen that Comparative Example 2 is coated and cured in one step, resulting in a very poor curing rate, which seriously affects the use of the dimming film.

[0091] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the utility model. Any simple modifications, equivalent changes, or alterations made to the above embodiments based on the technical principles of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A steady-state low-transmittance dimming film, comprising a dimming film body (1), characterized in that: The dimming film body (1) includes a first transparent substrate (11), a first transparent conductive layer (12), an active layer (13), a second transparent conductive layer (14), and a second transparent substrate (15) stacked in sequence, wherein the dark state transmittance of the dimming film body (1) is ≤0.5%.

2. The steady-state low transmittance dimming film according to claim 1, characterized in that: The dark transmittance of the dimming film body (1) is ≤0.3%.

3. The steady-state low transmittance dimming film according to claim 1, characterized in that: The light transmittance of the dimming film body (1) in the bright state is ≥5%.

4. The steady-state low transmittance dimming film according to claim 1, characterized in that: The light transmittance of the dimming film body (1) in the bright state is ≥15%.

5. The steady-state low transmittance dimming film according to claim 1, characterized in that: The light transmittance of the dimming film body (1) in the bright state is ≥20%.

6. The steady-state low transmittance dimming film according to claim 1, characterized in that: The active layer (13) is selected from suspended particle active layer, polymer dispersed liquid crystal active layer, and electrochromic active layer.

7. The steady-state low transmittance dimming film according to claim 1, characterized in that: The first transparent conductive layer (12) and the second transparent conductive layer (14) are each independently selected from one of the following: ITO conductive layer, FZO conductive layer, IZO conductive layer, GZO conductive layer, AZO conductive layer, PEDOT conductive layer, nano Ag wire conductive layer, conductive graphene, conductive polymer and nano Cu wire conductive layer.

8. The steady-state low transmittance dimming film according to claim 1, characterized in that: The first transparent substrate (11) and the second transparent substrate (15) are transparent plastic sheets.

9. A steady-state low-transmittance dimming glass, characterized in that, include: First transparent glass (2); Second transparent glass (3); And a steady-state low-transmittance dimming film as described in any one of claims 1 to 8 disposed between the first transparent glass (2) and the second transparent glass (3).

10. The steady-state low-transmittance dimming glass according to claim 9, characterized in that: A first interlayer (4) is provided between the first transparent glass (2) and the dimming film body (1), and / or a second interlayer (5) is provided between the second transparent glass (3) and the dimming film body (1).

11. The steady-state low-transmittance dimming glass according to claim 10, characterized in that: The materials of the first interlayer (4) and the second interlayer (5) are selected from one of EVA film, TPU film and PVB film.

12. The steady-state low-transmittance dimming glass according to claim 9, characterized in that: The first transparent glass (2) and the second transparent glass (3) are respectively selected from inorganic glass or organic glass.

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