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

Abstract

According to the technical scheme, the steady-state low-light-transmittance light valve comprises a light valve body. The light valve is characterized in that the light valve comprises a first transparent substrate, a first transparent conducting layer, a first active layer, a second transparent conducting layer, a second transparent substrate, a third transparent conducting layer, a second active layer, a fourth transparent conducting layer and a third transparent substrate which are sequentially stacked, and the steady-state light transmittance of the light valve is smaller than or equal to 0.5%. According to the utility model, the problem of high steady-state light transmittance of the light valve can be effectively solved, so that the steady-state light transmittance is reduced to below 0.5%.

Description

TECHNICAL FIELD

[0001] The utility model relates to light modulation technical field especially is related to a steady state low transmittance light valve and dimming glass. BACKGROUND

[0002] The light valve is a light control device, which mainly sets a light modulation active layer between two transparent conductive films. The light valve types include suspended particle (SPD) light valve, polymer dispersed liquid crystal (PDLC) light valve, and electrochromic (EC) light valve. For the suspended particle light valve, polymer dispersed liquid crystal light valve, and electrochromic light valve, when the power is turned on, the arrangement or state of the material in the light valve changes, thereby changing the light transmittance characteristics of the light valve, such as converting from low transmittance to high transmittance, or converting from high transmittance to low transmittance. This type of light valve, which can realize fast conversion between the on-state and the off-state through the action of an electric field / current, has the advantages of actively regulating light transmittance and energy saving, and can be used as intelligent windows of spacecrafts, high-speed trains, vehicles, buildings, and rearview mirrors, sunglasses, displays, etc.

[0003] Although the light valve has been successfully developed for many years, for the UV-cured light valve with a steady state dark state, the dark state transmittance is relatively high, generally exceeding 0.5%. Such light valves have poor light shielding performance, thereby limiting the application field of such light valves. The reason is that, during the production of such light valves, if the dark state transmittance is too low, it will cause the UV light to be difficult to penetrate the wet film of the light valve during the UV curing process, resulting in incomplete curing of the active layer of the light valve, which seriously affects the performance of the light valve.

[0004] It can be seen that the steady state transmittance of the UV-cured light valve with a steady state dark state is relatively high in the prior art. Therefore, it is necessary to invent a light valve with lower steady state transmittance. SUMMARY

[0005] In view of the above problems, the utility model aims to provide a steady state low transmittance light valve and dimming glass to change the problem of high steady state transmittance of the light valve.

[0006] The technical scheme of the utility model is a steady state low transmittance light valve, which comprises a light valve, characterized in that: the light valve comprises a first transparent substrate, a first transparent conductive layer, a first active layer, a second transparent conductive layer, a second transparent substrate, a third transparent conductive layer, a second active layer, a fourth transparent conductive layer, and a third transparent substrate which are sequentially stacked, and the steady state transmittance of the light valve is ≤0.5%.

[0007] Preferably, the steady state transmittance of the light valve is ≤0.3%.

[0008] Preferably, the bright state transmittance of the light valve is ≥5%.

[0009] Preferably, the light transmittance of the bright state of the light valve is greater than or equal to 15%.

[0010] Preferably, the light transmittance of the bright state of the light valve is greater than or equal to 20%.

[0011] Preferably, the first active layer and the second active layer are each independently selected from a suspended particle active layer, a polymer dispersed liquid crystal active layer, and an electrochromic active layer.

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

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

[0014] Preferably, the first transparent conductive layer and / or the second transparent conductive layer and / or the third transparent conductive layer and / or the fourth transparent conductive layer is / are covered with an adhesive layer on the surface facing the active layer; the adhesive layer is made of one of an epoxy resin, a polyurethane, a polyimide resin, a polystyrene resin, an acrylic resin, a modified acrylic resin, or a silicone resin.

[0015] The utility model provides a kind of steady-state low light transmittance dimming glass, comprising: first transparent glass, second transparent glass and the above-mentioned steady-state low light transmittance light valve between the first transparent glass and second transparent glass.

[0016] Preferably, a first interlayer is provided between the first transparent glass and the light valve, and / or a second interlayer is provided between the second transparent glass and the light valve.

[0017] Preferably, the first interlayer and the second interlayer are made of one of EVA film, TPU film and PVB film.

[0018] Preferably, the first transparent glass and the second transparent glass are made of inorganic glass or organic glass.

[0019] The utility model can achieve the effect of steady-state low light transmittance, has the characteristics of good shielding light transmittance and good privacy, thereby expanding the application field of dimming glass. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a structural schematic view of the light valve of the utility model;

[0021] Figure 2A structure schematic view of the light-adjustable glass;

[0022] Figure 3 A structure principle schematic view of the light valve prepared by the utility model;

[0023] 1 - light valve; 11 - first transparent substrate; 12 - first transparent conductive layer; 13 - first active layer; 14 - second transparent conductive layer; 15 - second transparent substrate; 16 - third transparent conductive layer; 17 - second active layer; 18 - fourth transparent conductive layer; 19 - third transparent substrate; 2 - first transparent glass; 3 - second transparent glass; 4 - first laminated layer; 5 - second laminated layer; p1, p2, p3 are coating dies, m1, m2 are transparent conductive films with transparent conductive layer on one side, n is a transparent conductive film with transparent conductive layer on both sides, f1, f2, f3 are coating rollers, q1, q2 are laminating rollers, r1, r2, r3 are curing units. DETAILED DESCRIPTION

[0024] The utility model will be further explained in detail in combination with the drawings.

[0025] In the utility model, the following terms used have the meanings as defined below.

[0026] The steady state of the light valve, i.e. the light transmission state of the light valve without applying electric field / current, generally, the steady state of the suspended particle light valve and the polymer dispersed liquid crystal light valve is dark state, and the bright state after applying electric field; and the steady state of the electrochromic light valve is bright state, and the dark state after applying current. Of course, there are also cases that the steady state of the suspended particle light valve and the polymer dispersed liquid crystal light valve is bright state, and the dark state after applying electric field; and the steady state of the electrochromic light valve is dark state, and the bright state after applying current.

[0027] The dark state of the light valve is the state with the minimum light transmittance of the light valve.

[0028] The bright state of the light valve is the state with the maximum light transmittance of the light valve.

[0029] The transition state of the light valve is the state with the light transmittance of the light valve between the dark state and the bright state.

[0030] The transparent conductive film, the transparent substrate and the transparent conductive layer can be a laminated combination of one transparent substrate and one transparent conductive layer, or a laminated combination of one transparent substrate and two transparent conductive layers distributed on both sides of the transparent substrate.

[0031] For example, Figure 1As shown, this utility model provides a steady-state low transmittance light valve, including a light valve 1, characterized in that: the light valve 1 includes a first transparent substrate 11, a first transparent conductive layer 12, a first active layer 13, a second transparent conductive layer 14, a second transparent substrate 15, a third transparent conductive layer 16, a second active layer 17, a fourth transparent conductive layer 18, and a third transparent substrate 19 stacked sequentially, and the steady-state transmittance of the light valve 1 is ≤0.5%.

[0032] In the above scheme, the steady-state transmittance of the light valve 1 is ≤0.3%.

[0033] Specifically, the light transmittance of the light valve 1 in the bright state is ≥5%.

[0034] Specifically, the light transmittance of the light valve 1 in the bright state is ≥15%.

[0035] Specifically, the light transmittance of the light valve 1 in the bright state is ≥20%.

[0036] Specifically, the first active layer 13 and the second active layer 17 are each independently selected from the suspended particle active layer, the polymer dispersed liquid crystal active layer, and the electrochromic active layer.

[0037] Specifically, the first transparent conductive layer 12, the second transparent conductive layer 14, the third transparent conductive layer 16, and the fourth transparent conductive layer 18 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.

[0038] Specifically, the first transparent substrate 11, the second transparent substrate 15, and the third transparent substrate 19 are transparent plastic sheets.

[0039] Specifically, the first transparent conductive layer 12 and / or the second transparent conductive layer 14 and / or the third transparent conductive layer 16 and / or the fourth transparent conductive layer 18 are covered with an adhesive layer on their surfaces facing the active layer; the adhesive layer material includes one of epoxy resin, polyurethane, polyimide resin, polystyrene resin, acrylic resin, modified acrylic resin or silicone resin.

[0040] like Figure 2 As shown, this utility model provides a steady-state low-transmittance dimming glass, including: a first transparent glass 2, a second transparent glass 3, and the aforementioned steady-state low-transmittance light valve disposed between the first transparent glass 2 and the second transparent glass 3.

[0041] Specifically, a first interlayer 4 is provided between the first transparent glass 2 and the light valve 1, and / or a second interlayer 5 is provided between the second transparent glass 3 and the light valve 1.

[0042] Specifically, the first and second interlayer 4, 5 are selected from one of EVA film, TPU film, PVB film.

[0043] Specifically, the first and second transparent glass 2, 3 are selected from inorganic glass or organic glass.

[0044] The preparation steps of the steady-state low-transmittance light valve are as follows:

[0045] As shown in Figure 3 Step a, on the transparent conductive layer side of the two single-sided transparent conductive films m1, m2 with transparent conductive layers, the active layer precursor is coated by coating die p1, p3, compounded by coating roller f1, f3, and cured by UV curing unit r1, r3,

[0046] Step b, the two products prepared in step a are laminated by lamination rollers q1 and q2, with the two-sided transparent conductive film n with transparent conductive layers arranged between the two active layers, forming a laminated structure of the first transparent substrate, the first transparent conductive layer, the first active layer, the second transparent conductive layer, the second transparent substrate, the third transparent conductive layer, the second active layer, the fourth transparent conductive layer, and the third transparent substrate.

[0047] Alternatively,

[0048] Step a, on the transparent conductive layer side of the single-sided transparent conductive film m2 with transparent conductive layer, the active layer precursor is coated by coating die p3, compounded by coating roller f3, and cured by UV curing unit r3,

[0049] Step b, on the transparent conductive layer side of the two-sided transparent conductive film n away from the transparent conductive layer of step a, the active layer precursor is coated by coating die p2, and cured by UV curing unit r2,

[0050] Step c, the products prepared in steps a and b are laminated with the single-sided transparent conductive film m1 with transparent conductive layer by lamination rollers q1 and q2, forming a laminated structure of the first transparent substrate, the first transparent conductive layer, the first active layer, the second transparent conductive layer, the second transparent substrate, the third transparent conductive layer, the second active layer, the fourth transparent conductive layer, and the third transparent substrate.

[0051] The active layer precursor is selected from suspended particle active layer precursor, polymer dispersed liquid crystal active layer precursor, and electrochromic active layer precursor.

[0052] The coating methods 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.

[0053] Furthermore, the preparation method of this steady-state low-transmittance dimming glass in this invention includes the following steps:

[0054] The layers of stable low-transmittance smart glass are sequentially stacked and then laminated to obtain smart glass. The lamination process is carried out at a temperature of 90–130°C and a pressure of 0.1–1.5 MPa.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] In practical use, the light transmittance of the dimming glass of this invention can be varied by controlling the first active layer 13 and the second active layer 17 to be in a dark state, a bright state, or a transitional state.

[0059] Finally, the dimming glass produced by this invention can be applied to glass products such as automotive windows, skylights, or glass curtain walls.

[0060] The general production process of a light valve involves coating and curing. When the steady state of the light valve is dark and the light transmittance is very low, for UV-cured light valves, the low light transmittance leads to poor UV light penetration, resulting in incomplete UV curing of the dimming active layer and affecting the quality of the light valve product.

[0061] This invention first uses UV curing to create a laminate of a transparent conductive layer and an active layer precursor with high light transmittance, and then laminates the two cured transparent conductive layers and active layers together to prepare a light valve, thus solving the problem of difficult UV curing for low light transmittance.

[0062] This invention calculates the curing rate of the light valve based on FT-IR test results:

[0063] The FT-IR data of the dimming active layer precursor (before curing) and the dimming active layer (after curing) were tested separately.

[0064] Curing rate % = (1 - (M1 / R1) / (M0 / R0)) * 100

[0065] M1 / R1 is the 1406 cm⁻¹ in the FT-IR spectrum of the light-adjusting active layer (after curing). -1 Peak area and 1740cm -1 The ratio of peak areas

[0066] M0 / R0 is the FT-IR spectrum of the light-tuning active layer precursor (before curing) at 1406 cm⁻¹. -1 The peak area is 1740 cm⁻¹ -1 The ratio of peak area.

[0067] A higher percentage of curing rate indicates a better curing effect.

[0068]

Example 1

[0069] The fabrication steps of the steady-state low transmittance light valve are as follows:

[0070] Step a: Prepare the precursor for the suspended particle dimming active layer according to the method in Example 5 of CN112882258A.

[0071] Step b, as follows Figure 3 As shown, on the transparent conductive layer sides of two transparent conductive films m1 and m2 with transparent conductive layers on one side, active layer precursors are coated using slit coating dies p1 and p3. The coating thickness of the suspended particle dimming active layer precursor is controlled to be 45 μm. The coating is then compounded using coating rollers f1 and f3, and cured under a nitrogen atmosphere using UV curing units r1 and r3. The UV curing time is 1 min, and the UV lamp power is 700 W / m. 2 ,

[0072] Step c, two pieces of the product prepared in step b are laminated by laminating rollers q1 and q2, with the transparent conductive film n with the two active layers in the middle and the transparent conductive layer on both sides, to form a laminated structure of the first transparent substrate, the first transparent conductive layer, the first active layer, the second transparent conductive layer, the second transparent substrate, the third transparent conductive layer, the second active layer, the fourth transparent conductive layer, and the third transparent substrate, that is, the light control film as shown in Figure 1 The test results are shown in Table 1.

[0073]

Example 2

[0074] The preparation steps of the steady-state low-transmittance light valve are as follows:

[0075] Step a, the suspension particle light control active layer precursor is prepared according to the method of Example 5 in CN112882258A,

[0076] Step b, as shown in Figure 3 , the active layer precursor is coated on the transparent conductive layer side of the transparent conductive film m2 with a transparent conductive layer on one side by a slot coating die p3, the coating thickness of the suspension particle light control active layer precursor is controlled to be 50 μm, and the coating is performed by a coating roller f3. In a nitrogen atmosphere, curing is performed by a UV curing unit r3, UV curing for 1 min, and the UV lamp power is 700 W / m 2 ,

[0077] Step c, the active layer precursor is coated on the transparent conductive layer side of the transparent conductive film n with a transparent conductive layer on both sides away from the transparent conductive layer of step b by a slot coating die p2, and curing is performed by a UV curing unit r2 in a nitrogen atmosphere, UV curing for 1 min, and the UV lamp power is 700 W / m 2 ,

[0078] Step d, the products prepared in steps b and c are laminated with a transparent conductive film m1 with a transparent conductive layer on one side by laminating rollers q1 and q2 to form a laminated structure of the first transparent substrate, the first transparent conductive layer, the first active layer, the second transparent conductive layer, the second transparent substrate, the third transparent conductive layer, the second active layer, the fourth transparent conductive layer, and the third transparent substrate, that is, the light control film as shown in Figure 1 The test results are shown in Table 1.

[0079]

Example 3

[0080] Two pieces of super white glass, two EVA adhesive layers, and the suspension particle light control film prepared in

Example 2

[0081] ​Comparative Example 1

[0082] The method of Example 7 in CN112882258A was used, except that the coating thickness of the suspended particle light modulation active layer precursor was controlled to be 20 μm, and the test results are shown in Table 1.

[0083] Comparative Example 2

[0084] The method of Comparative Example 1 was used, except that the coating thickness of the suspended particle light modulation active layer precursor was controlled to be 100 μm, and the test results are shown in Table 1.

[0085] Table 1

[0086] Example Total coating thickness μm Dark-state light transmittance Bright-state light transmittance Curing rate Example 1 90 0.10% 38.5% 99.3% Example 2 100 0.04% 40.2% 99.1% Example 3 Not applicable 0.08% 37.7% Not applicable Comparative Example 1 20 20.80% 71.8% 99.8% Comparative Example 2 100 0.06% 39.6% 56.7%

[0087] # Power supply: voltage effective value 110V, 60Hz

[0088] As can be seen from the results in Table 1, the preparation method of the present application can obtain a light valve with UV curing and very low steady-state dark-state light transmittance. Since the light modulation active layer is divided into two layers, the single-layer coating thickness is thin, and the influence on the penetration of UV light is small, the expected curing effect can be achieved. Comparative Example 2 was compared with Example 2, and it can be seen that Comparative Example 2 was coated and cured once, resulting in a very poor curing rate, which seriously affects the use of the light modulation film.

[0089] The above is only a preferred embodiment of the present application, and does not limit the application in any form. Any simple modification, equivalent change or modification made according to the technical principles of the present application to the above embodiments still falls within the scope of the technical solutions of the present application.

Claims

1. A steady state low-transmission light valve comprising a light valve (1), characterized in that: The light valve (1) comprises a first transparent substrate (11), a first transparent conductive layer (12), a first active layer (13), a second transparent conductive layer (14), a second transparent substrate (15), a third transparent conductive layer (16), a second active layer (17), a fourth transparent conductive layer (18) and a third transparent substrate (19) which are sequentially stacked, and the steady-state light transmittance of the light valve (1) is ≤0.5%.

2. A steady state low-transmission light valve according to claim 1, characterized in that: The steady-state light transmittance of the light valve (1) is ≤0.3%.

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

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

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

6. A steady state low-transmission light valve according to claim 1, wherein: The first active layer (13) and the second active layer (17) are each independently selected from a suspended particle active layer, a polymer dispersed liquid crystal active layer and an electrochromic active layer.

7. A steady state low-transmission light valve according to claim 1, wherein: The first transparent conductive layer (12), the second transparent conductive layer (14), the third transparent conductive layer (16) and the fourth transparent conductive layer (18) are each independently selected from one of an ITO conductive layer, an FZO conductive layer, an IZO conductive layer, a GZO conductive layer, an AZO conductive layer, a PEDOT conductive layer, a nano-Ag wire conductive layer, conductive graphene, a conductive polymer and a nano-Cu wire conductive layer.

8. A steady state low-transmission light valve according to claim 1, wherein: The first transparent substrate (11), the second transparent substrate (15) and the third transparent substrate (19) are transparent plastic sheets.

9. A steady state low-transmission light valve according to claim 1, wherein: The surface of the first transparent conductive layer (12) and / or the second transparent conductive layer (14) and / or the third transparent conductive layer (16) and / or the fourth transparent conductive layer (18) facing the active layer is covered with an adhesive layer; the material of the adhesive layer comprises one of an epoxy resin, a polyurethane, a polyimide resin, a polystyrene resin, an acrylic resin, a modified acrylic resin or a silicone resin.

10. A steady state low light transmittance switchable glass, characterized by: Comprise: A first transparent glass (2), a second transparent glass (3), and a steady-state low light transmittance light valve as claimed in any one of claims 1 to 9 arranged between the first transparent glass (2) and the second transparent glass (3).

11. The steady state low light transmittance switchable glass according to claim 10, wherein: A first interlayer adhesive layer (4) is arranged between the first transparent glass (2) and the light valve (1), and / or a second interlayer adhesive layer (5) is arranged between the second transparent glass (3) and the light valve (1).

12. The steady state low light transmittance switchable glass according to claim 11, wherein: The material of the first interlayer adhesive layer (4) and the second interlayer adhesive layer (5) is selected from one of an EVA adhesive film, a TPU adhesive film and a PVB adhesive film.

13. The steady state low light transmittance switchable glass according to claim 10, wherein: The first transparent glass (2) and the second transparent glass (3) are selected from inorganic glass or organic glass. The first transparent glass (2) and the second transparent glass (3) are selected from inorganic glass or organic glass.

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