Dimming laminate and smart window including same

Abstract

The present invention relates to a dimming laminate and a smart window comprising the same, the dimming laminate comprising: a first laminate comprising a first polarizing plate and a first transparent conductive layer; a second laminate facing the first laminate and including a second polarizing plate and a second transparent conductive layer; and a liquid crystal layer disposed between the first laminate and the second laminate, the first laminate and the second laminate each having a Martens hardness (HM) of 100 N / mm2 or more and 430 N / mm2 or less and an elastic recovery rate (nIT) of 40% or more and 87% or less when a pressing load of 1 mN is applied to the first laminate and the second laminate for 15 seconds using a nanoindenter. Since the polarizing plate-transparent conductive layer laminate positioned on the upper and lower portions of the liquid crystal layer has excellent hardness without deformation, has excellent elastic recovery rate, and can recover after being pressed, there is no appearance defects such as bubbles and black spots, and driving is smooth.

Description

Technical Field

[0001] This invention relates to a dimming laminate and a smart window comprising the same. Background Technology

[0002] Generally, the windows of vehicles and other mobile vehicles are often coated with an external light-blocking coating. However, the transmittance of conventional mobile vehicle windows is fixed, and so is the transmittance of the external light-blocking coating. Therefore, since the overall transmittance of such conventional mobile vehicle windows is fixed, it may cause accidents. For example, if the overall transmittance is set low, there is no problem during the day when the ambient light is sufficient. However, in situations such as nighttime when the ambient light is insufficient, it is difficult for drivers or others to properly see the surroundings of the mobile vehicle. On the other hand, if the overall transmittance is set high, it may cause glare for drivers or others during the day when the ambient light is sufficient. To address this, a light-modulating laminate that can change the light transmittance when a voltage is applied has been developed. For example, Japanese Patent Publication No. 2018-010035 discloses a light-modulating laminate with variable transmittance, which includes a transparent conductive layer formed on a polycarbonate (PC) substrate or the like having a predetermined thickness.

[0003] On the other hand, such dimming laminates are manufactured by adding a liquid crystal layer between two laminated structures containing a polarizing plate and a transparent conductive layer. During the manufacturing process of the dimming laminate, there is a problem where the liquid crystal layer cannot be restored after being pressed during the pressing process of the polarizing plate and / or the transparent conductive layer, resulting in bubbles and black spots, and poor drive operation. In particular, to simplify the manufacturing process of the transmittance-variable dimming laminate and reduce its thickness, when the polarizing plate and the transparent conductive layer are directly contacted to form a composite layer without including a separate substrate for the conductive layer used to form the transmittance-variable dimming laminate, since a separate substrate is usually not included, in addition to ensuring a thinner layer, further development may be needed to improve mechanical properties or achieve excellent appearance quality. Therefore, in practice, there is a need to develop a polarizing plate and transparent conductive layer laminate that ensures both a thinner thickness and excellent appearance and mechanical properties, making it particularly suitable for smart windows.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Publication No. 2018-010035 Summary of the Invention

[0007] The problem to be solved

[0008] The purpose of this invention is to provide a dimming laminate, in which, especially in the case where the polarizing plate and the transparent conductive layer are formed in direct contact, the generation of bubbles and black spots is minimized by adjusting the Martens hardness and elastic recovery rate of the polarizing plate-transparent conductive layer laminate, thereby making the drive smooth.

[0009] The object of the present invention is to provide a dimming laminate comprising a polarizing plate-transparent conductive layer laminate having a martensitic hardness and elastic recovery rate particularly suitable for smart windows, and a smart window comprising the same.

[0010] However, the problems to be solved by the present invention are not limited to those mentioned above, and those skilled in the art should be able to clearly understand other problems not mentioned based on the following description.

[0011] Methods for solving problems

[0012] This invention relates to a dimming laminate comprising: a first laminate including a first polarizing plate and a first transparent conductive layer; a second laminate opposite to the first laminate and including a second polarizing plate and a second transparent conductive layer; and a liquid crystal layer disposed between the first laminate and the second laminate, wherein the martensitic hardness (HM) of each of the first laminate and the second laminate is 100 N / mm² when a 1 mN compressive load is applied to the surface of the laminate for 15 seconds in the lamination direction using a nanoindenter. 2 The above 430N / mm 2 The following values ​​represent elastic recovery rate (nIT) values ​​between 40% and 87%.

[0013] In one embodiment of the present invention, the first transparent conductive layer and the second transparent conductive layer may each independently comprise one or more of the following: transparent conductive oxides, metals, carbon-based substances, conductive polymers, conductive inks, and nanowires.

[0014] In one embodiment of the present invention, the first polarizing plate and the second polarizing plate can each independently be one of an iodine-based polarizing plate, a polyene-based polarizing plate, and a dye-based polarizing plate.

[0015] In one embodiment of the present invention, the thickness of the first polarizing plate and the second polarizing plate can each be independently 30 to 300 μm.

[0016] In one embodiment of the present invention, the first polarizing plate and the second polarizing plate may each independently include a hard coating, and the hard coating may include inorganic fillers.

[0017] In another example of the present invention, the inorganic filler may comprise silica particles with an average particle size of less than 20 nm.

[0018] In another embodiment of the present invention, the aforementioned hard coating may be formed with a thickness of 3 to 25 μm.

[0019] In one embodiment of the present invention, the periphery of the first laminate may further include a first glass, and the periphery of the second laminate may further include a second glass.

[0020] In one embodiment of the present invention, a first bonding layer may be included between the first laminate and the first glass, and a second bonding layer may be included between the second laminate and the second glass. The bonding layer may be one or more selected from polyvinyl butyral (PVB) and ethylene vinyl acetate (EVA).

[0021] In one embodiment of the present invention, at least one of the first and second transparent conductive layers can be formed to be in direct contact with the first or second polarizing plate without including a separate substrate.

[0022] In one embodiment of the present invention, at least one of the first polarizing plate and the second polarizing plate may include one or more functional layers selected from the group consisting of a protective layer, a phase difference adjustment layer and a refractive index adjustment layer.

[0023] In one embodiment of the present invention, the dimming laminate may further include one or more of an adhesive / bonding layer and an ultraviolet absorption layer.

[0024] Additionally, this relates to smart windows that incorporate a dimming laminate comprising one or another embodiment of the present invention.

[0025] Invention Effects

[0026] According to the dimming laminate of the present invention, by adjusting the Martens hardness and elastic recovery rate of the polarizing plate-transparent conductive layer laminate located on the upper and lower parts of the liquid crystal layer, a dimming laminate in which bubbles and black spots are minimized and the variable transmittance function is smoothly driven can be manufactured, which is particularly suitable for dimming laminates for smart windows.

[0027] Furthermore, according to the dimming laminate of the present invention, by directly forming a conductive layer on one side of a polarizing plate without including a separate substrate for forming the conductive layer, the thickness can be significantly reduced compared to conventional dimming laminates.

[0028] Furthermore, as mentioned above, since the polarizer-transparent conductive layer laminate has excellent martensitic hardness and elastic recovery rate, it can provide a thin but strong dimming laminate. Attached Figure Description

[0029] Figure 1 This is a diagram illustrating the stacked structure of a dimming laminate according to an embodiment of the present invention.

[0030] Figure 2 A diagram showing the structure of a polarizing plate-transparent conductive layer stack, which is an object for evaluating the compressibility properties of an embodiment of the present invention.

[0031] Figure 3a This is a cross-sectional view illustrating a dimming laminate according to an embodiment of the present invention.

[0032] Figure 3b This is a cross-sectional view illustrating the dimming laminate of Comparative Example 1 included in the experimental examples of the present invention.

[0033] Figures 4a to 4e This is a diagram illustrating the stacked structure of a polarizing plate according to one or more embodiments of the present invention. Detailed Implementation

[0034] This invention relates to a dimming laminate and a smart window comprising the same, the dimming laminate being characterized in that it comprises: a first laminate comprising a first polarizing plate and a first transparent conductive layer; a second laminate opposite to the first laminate and comprising a second polarizing plate and a second transparent conductive layer; and a liquid crystal layer disposed between the first laminate and the second laminate, wherein the martensitic hardness (HM) of each of the first laminate and the second laminate is 100 N / mm. 2 The above 430N / mm 2 The following values ​​represent elastic recovery rate (nIT) values ​​between 40% and 87%.

[0035] More specifically, the first and second laminates described above can each be adjusted such that, after being fixed to the glass with an adhesive, the martensitic hardness (HM) of the laminate surface is 100 N / mm² when a 1 mN compressive load is applied for 15 seconds in the lamination direction using a nanoindenter. 2 The above 430N / mm 2 The elastic recovery rate (nIT) is in the range of 40% to 87%. The type or thickness of the adhesive is not particularly limited as long as it is used for the purpose of fixing the first and second laminates onto the nanoindenter, and it can be used within a range that does not affect the martensitic hardness of the first and second laminates.

[0036] In one embodiment of the present invention, if the Martens hardness of the first laminate and the second laminate is less than 100 MPa, the impact resistance may be reduced; if it is greater than 430 MPa, the bending resistance may be worse.

[0037] The dimming laminate and smart window of the present invention have excellent martensitic hardness, do not deform and maintain their shape, and have excellent elastic recovery rate, which can recover after being pressed. Therefore, they have the advantages of being able to be manufactured without appearance defects such as bubbles and black spots, and smooth driving of variable transmittance function.

[0038] In this invention, martensitic hardness refers to the hardness measured under an applied test load (indentation), which can be obtained from the load-indentation depth curve as the load increases. Martensitic hardness includes both plastic and elastic deformation components. Martensitic hardness is defined specifically for square pyramidal indenters and triangular pyramidal indenters. Specifically, as shown in Equation 1 below, it is defined as the test load F divided by the surface area As penetrated by the indenter from the zero contact point.

[0039] <Formula 1>

[0040] Martens hardness = F / As

[0041] Martens hardness is obtained, for example, by a load-indentation depth test according to the method specified in ISO 14577. An example of the specific determination method is shown below.

[0042] The indentation test was performed according to the sequence and method specified in ISO 14577. A microhardness tester (e.g., FISCHERSCOPE 100C, manufactured by Fischer Instruments) was used, employing a pyramidal diamond indenter with a square base and a 136° angle between opposite faces. Specifically, the test object was fixed to glass at a level of several hundred μm using an adhesive with a thickness of approximately several μm, and the load application and removal times were each set to 15 seconds for evaluation. The test temperature was set to 23°C, and the indenter was pressed into the surface of the polarizing plate-transparent conductive layer laminate at a constant speed with a load of 1 mN applied for 15 seconds. The Martens hardness was calculated by applying a load (1 mN) to the surface of the polarizing plate-transparent conductive layer laminate and dividing this load by the surface area of ​​the indenter penetrating beyond the contact zero point.

[0043] The dimming laminate of the present invention is particularly suitable for the field of technology that can change the light transmittance according to the application of voltage, for example, it can be used in smart windows, etc.

[0044] A smart window is an optical structure that controls the amount of light or heat passing through by changing the light transmittance based on the application of an electrical signal. In other words, a smart window can change between transparent, opaque, or translucent states depending on the voltage; it is also known as variable transmittance glass, dimming glass, or smart glass.

[0045] Smart windows can be used as partitions to divide interior spaces in vehicles and buildings or as privacy partitions, or as windows for lighting in building openings. They can also be used as highway signs, billboards, scoreboards, clocks or advertising screens, and can replace the glass of transportation vehicles such as windows or skylights in cars, buses, airplanes, ships or trains.

[0046] The dimming laminate of the present invention can also be used as a smart window in the above-mentioned technical fields. However, since the conductive layer is formed directly on the polarizing plate without including a separate substrate for forming the conductive layer, it is thin and has good bending properties, making it particularly suitable for use in smart windows for vehicles or buildings. In one or more embodiments, a smart window using the dimming laminate of the present invention can be used as a front window, rear window, side window, and sunroof of a car, or a window for a building, etc. In addition to its use for blocking external light, it can also be used for interior space division or privacy protection purposes in cars or buildings, such as as an interior partition.

[0047] Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the following drawings accompanying this specification are merely illustrative of preferred embodiments of the present invention and serve to further illustrate the above-described invention and its technical concept. Therefore, the present invention should not be interpreted solely as described in these drawings.

[0048] The terminology used in this specification is intended to describe embodiments and is not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated in the context. For example, as used herein, "polarizing plate" may refer to at least one of a first polarizing plate and a second polarizing plate, and "transparent conductive layer" may refer to at least one of a first transparent conductive layer and a second transparent conductive layer.

[0049] The terms "comprises" and / or "comprising" as used herein are used to mean that they do not exclude the presence or addition of more than one other component, step, operation, and / or element besides those mentioned. Throughout this specification, the same reference numerals refer to the same components.

[0050] As illustrated in the accompanying drawings, spatially relative terms such as "below," "bottom," "lower part," "above," "upper surface," and "upper part" are used to readily describe the relationship between one element or component and other elements or components. Spatially relative terms should be understood in accordance with terms relating to the different orientations of the elements during use or operation, in addition to those illustrated in the drawings. For example, when the elements illustrated in the drawings are flipped, an element described as "below" or "lower part" of another element can be placed "above" the other element. Therefore, the illustrative term "below" can include both the lower and upper orientations. Elements can also be oriented in other directions, so spatially relative terms can be interpreted according to orientation.

[0051] In this invention, "peripheral portion" can refer to the outermost part of the dimming laminate, for example, it can be the opposite concept to the liquid crystal layer located in the center of the dimming laminate.

[0052] The term "viewing direction" as used in this specification can be interpreted as a direction orthogonal to the polarizing plate and / or the transparent conductive layer, i.e., the direction of view from the user's visible side.

[0053] <Dimming Layer>

[0054] The dimming laminate of the present invention may include: a first laminate comprising a first polarizing plate 210 and a first transparent conductive layer 310; a second laminate opposite to the first laminate and comprising a second polarizing plate 220 and a second transparent conductive layer 320; and a liquid crystal layer 400 disposed between the first laminate and the second laminate.

[0055] Figure 1 This is a diagram illustrating the stacked structure of a dimming laminate according to an embodiment of the present invention. (Refer to...) Figure 1 In one embodiment of the present invention, the dimming laminate may include a first polarizing plate 210, a second polarizing plate 220, a liquid crystal layer 400, a first transparent conductive layer 310, and a second transparent conductive layer 320.

[0056] The dimming laminate of the present invention can be suitably applied, for example, to smart windows. In particular, in cases where the polarizer must contain separate elements such as electrodes, the compressibility properties are determined not only by the properties of the individual materials contained in the polarizer and the transparent conductive layer, but also by the constituent elements. Therefore, with this in mind, the compressibility properties of the polarizer-transparent conductive layer laminate, especially its hardness and elastic recovery rate, can be adjusted by adding a hard coating to the polarizer, using a material with a high molecular weight, increasing or decreasing the thickness of the transparent conductive layer, or using a material with excellent hardness characteristics. If the hardness is too high, cracks and other defects may occur during the bonding process.

[0057] Specifically, the dimming laminate of the present invention can be manufactured with suitable martensitic hardness and elastic recovery rate by adjusting the thickness of the hard coating formed on the polarizing plate, whether inorganic fillers are added to the hard coating, and adjusting the thickness of the transparent conductive layer. If the martensitic hardness and elastic recovery rate of the first laminate and the second laminate are adjusted to satisfy a martensitic hardness (HM) of 100 N / mm² by adjusting the constituent elements as described above... 2 The above 430N / mm 2 If the elastic recovery rate (nIT) is between 40% and 87%, it can be determined that the polarizing plate-transparent conductive layer laminate has sufficient mechanical properties and will not exhibit the phenomenon of morphological changes due to pressure during the bonding process of the polarizing plate-transparent conductive layer laminate with the liquid crystal layer, resulting in bubble formation. Therefore, it is possible to manufacture a dimming laminate with excellent martensitic hardness, which maintains its shape without deformation, and excellent elastic recovery rate, which can recover after being pressed, without producing undesirable appearance.

[0058] At this time, if either the first stack or the second stack does not meet the above range, the polarizing plate-transparent conductive layer stack will shrink significantly, making it difficult for the bonding layer to remain fixed. This may result in wrinkles in the stack, causing appearance defects such as bubbles and black spots, or the stack may not be able to be driven as a dimming stack.

[0059] For smart windows, transparency and visibility are crucial factors. Unlike traditional LCD displays, smart windows do not contain a supporting substrate between layers. Due to their structural characteristics, the polarizing plate has a significant impact on the appearance. Besides ensuring a thinner layer thickness, further development may be needed to improve mechanical properties or achieve superior aesthetic quality. Therefore, to use the dimming laminate in smart windows, the hardness of the polarizing plate-transparent conductive layer laminate must be considered. From this perspective, Marlowan hardness is appropriate for identifying defects and trends in the composite layer, as it also reflects the properties of the underlying layers.

[0060] The aforementioned bubbles and / or black spots may appear on the outer periphery of the first and second layers of the dimming laminate, particularly on the surfaces of the first and second layers that contact glass or the like. For example, refer to the defective... Figure 3b In the manufacture of which appeared Figure 3b In the case of smart windows with dimming overlays, the visible black spots may spread so severely throughout the entire window that they render it unusable, rather than appearing only in specific areas such as the periphery or center.

[0061] The first and second layers mentioned above can be the same as each other or different.

[0062] Polarizing plate 210, 220

[0063] The first polarizing plate 210 and the second polarizing plate 220 can each independently be one of an iodine-based polarizing plate, a polyene-based polarizing plate, or a dye-based polarizing plate. In particular, when it is an iodine-based polarizing plate, it is suitable for smart windows due to its high transmittance.

[0064] In one or more embodiments, the first polarizing plate and the second polarizing plate may each have a thickness of 30 to 300 μm, preferably 30 to 250 μm, and more preferably 50 to 200 μm. When the thickness of the substrate is less than 30 μm, the impact resistance may decrease, and when it is greater than 300 μm, the bending resistance may decrease relatively.

[0065] Reference Figures 4a to 4e The first polarizing plate 210 and the second polarizing plate 220 each include a polarizer 201. Functional layers such as a protective layer 202, a phase difference adjustment layer 203, and a refractive index adjustment layer 204 may also be included on one or both sides of the polarizer. In this case, the composition of the functional layers included in the first polarizing plate and the second polarizing plate may be the same or different. The Martens hardness and elastic recovery rate of the polarizing plate-transparent conductive layer laminate can be adjusted according to the type and thickness of the layers constituting the polarizing plate, the thickness of the conductive layer, etc.

[0066] For example, a polarizing plate may include a polarizer 201 and a protective layer 202 stacked on one or both sides of the polarizer 201 (see reference). Figure 4a and Figure 4b It may include a polarizer 201, a protective layer 202 stacked on one side of the polarizer 201, and a phase difference adjustment layer 203 stacked on the other side of the polarizer 201 opposite to the aforementioned side (see reference). Figure 4c It may include a polarizer 201, a protective layer 202 stacked on one side of the polarizer, and a phase difference adjustment layer 203 and a refractive index adjustment layer 204 sequentially stacked on the opposite side of the polarizer 201 (see reference). Figure 4d It may include a polarizer 201, a protective layer 202 stacked on one side of the polarizer, and a protective layer 202 and a phase difference adjustment layer 203 sequentially stacked on the other side of the polarizer 201 opposite to the aforementioned side (see reference). Figure 4e ).

[0067] As an example, the first and second polarizing plates described above may each have a first protective layer and a second protective layer on one and the other side, respectively, centered on a polarizer such as PVA. The first and second protective layers are intended to protect the polarizer. As one embodiment of the protective layers, they can be provided using materials described later; specifically, cellulose triacetate (TAC) or polyethylene terephthalate (PET) can be used. Alternatively, an adhesive / binder can be used to bond the polarizer to the first and second protective layers. There are no particular limitations on the adhesive / binder as long as it has suitable adhesive strength, transparency, and thermal stability. The bonding method between the polarizer and the first and / or second protective layers using the adhesive / binder can be implemented using bonding methods commonly used in the art. For example, the following methods can be used: after applying an adhesive / bonding agent composition to the bonding surface of the polarizer or protective layer using flexible coating, Mayer bar coating, gravure coating, die coating, dip coating, spray coating, etc., the polarizer or protective layer can be inserted into a clamping roller or the like for bonding.

[0068] The polarizer 201 described above can use polarizers that have been developed in the past or in the future, such as stretch polarizers or coating polarizers.

[0069] In one embodiment, the stretched polarizer may comprise a stretched polyvinyl alcohol (PVA) resin. The PVA resin may be a polyvinyl alcohol resin obtained by saponifying a polyvinyl acetate (PVC) resin. Besides PVC homopolymers, copolymers of PVC with other monomers that can copolymerize with PVC can also be cited as PVC resins. These other monomers may be unsaturated carboxylic acid monomers, unsaturated sulfonic acid monomers, olefin monomers, vinyl ether monomers, or acrylamide monomers with ammonium groups. Furthermore, the PVA resin may include modified substances, such as aldehyde-modified polyvinyl alcohol formaldehyde or polyvinyl alcohol acetal.

[0070] In one embodiment, the above-mentioned coated polarizer can be formed using a liquid crystal coating composition, wherein the liquid crystal coating composition may include a reactive liquid crystal compound and a dichroic dye, etc.

[0071] The aforementioned reactive liquid crystal compounds can refer, for example, to compounds containing a mesogen framework and one or more polymerizable functional groups. Such reactive liquid crystal compounds are widely known under the name "Reactive Mesogen (RM)". These reactive liquid crystal compounds can be polymerized by means of light or heat to form a cured film that maintains the liquid crystal arrangement while forming a polymer network.

[0072] The aforementioned reactive liquid crystal compounds can be monofunctional or polyfunctional reactive liquid crystal compounds. Monofunctional reactive liquid crystal compounds can refer to compounds having one polymerizable functional group, while polyfunctional reactive liquid crystal compounds can refer to compounds containing two or more polymerizable functional groups.

[0073] The aforementioned dichroic dye is a component included in a liquid crystal coating composition to impart polarizing properties, possessing the property that the absorbance along the long axis of the molecule differs from the absorbance along the short axis. The aforementioned dichroic dye can be any conventionally or subsequently developed dichroic dye, for example, it can include one or more dyes selected from the group consisting of azo dyes, anthraquinone dyes, perylene dyes, merocyanine dyes, azomethine dyes, phthaloperylene dyes, indigo dyes, dioxazine dyes, polythiophene dyes, and phenoxazine dyes.

[0074] The liquid crystal coating composition described above may further include a solvent capable of dissolving the reactive liquid crystal compound and the dichroic dye, such as propylene glycol monomethyl ether acetate (PGMEA), methyl ethyl ketone (MEK), xylene, and chloroform. Furthermore, the liquid crystal coating composition may also include a leveling agent, a polymerization initiator, etc., within a range that does not impede the polarization properties of the coated film.

[0075] The aforementioned protective layer 202 is intended to protect the polarization characteristics of the polarizer 201 from the influence of subsequent processes and the external environment, and can be implemented in the form of a protective film or the like.

[0076] like Figure 4a and Figure 4bAs illustrated, the protective layer 202 can be formed in direct contact with one or both surfaces of the polarizer 201, but is not limited thereto. For example, the protective layer can also be used in a multilayer structure consisting of one or more protective layers stacked continuously, and can be formed in direct contact with other functional layers.

[0077] In one or more embodiments, the protective layer 202 may comprise one or more polymers selected from polyethylene terephthalate (PET), polyethylene isophthalate (PEI), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), diacetyl cellulose, triacetyl cellulose (TAC), polycarbonate (PC), polyethylene (PE), polypropylene (PP), polymethyl acrylate (PMA), polymethyl methacrylate (PMMA), polyethyl acrylate (PEA), polyethyl methacrylate (PEMA), and cyclic olefin polymers (COP).

[0078] The aforementioned phase difference adjustment layer 203 is intended to supplement the optical characteristics of the dimming stack and can be implemented in the form of a phase difference film, etc., which can be phase difference films developed in the past or in the future. For example, in order to suppress phase delay, a zero phase difference plate with an in-plane phase difference that is substantially close to 0 can be used, or a quarter-wave plate (1 / 4 wave plate) or a half-wave plate (1 / 2 wave plate) used to delay the phase of light can be used, which can be used alone or in combination.

[0079] like Figure 4c and Figure 4d As illustrated, the phase difference adjustment layer 203 can be formed in direct contact with one side of the polarizer 201, but is not limited to this. For example, as Figure 4e As illustrated, the phase difference adjustment layer 203 can be formed on one side of the protective layer 202, thereby stacking the polarizer 201, the protective layer 202 and the phase difference adjustment layer 203 in sequence.

[0080] The phase difference adjustment layer 203 described above can be a polymer stretch film or a liquid crystal polymer film obtained by stretching a polymer film capable of imparting optical anisotropy in an appropriate manner through stretching.

[0081] In one embodiment, the aforementioned polymeric stretch film may use a polymeric layer comprising the following substances: polyolefins such as polyethylene (PE) or polypropylene (PP), cyclic olefin polymers (COP) such as polynorbornene, polyvinyl chloride (PVC), polyacrylonitrile (PAN), polysulfone (PSU), acrylic resin, polycarbonate (PC), polyethylene terephthalate (PET), cellulose ester polymers such as polyacrylate, polyvinyl alcohol (PVA), or triacetyl cellulose (TAC), or copolymers of two or more monomers forming the aforementioned polymers.

[0082] There are no particular limitations on the method for obtaining the above-mentioned polymer stretched film. For example, it can be obtained by stretching the polymer material after molding it into a film. There are no particular limitations on the method of molding it into a film. It can be formed into a film using known methods such as injection molding, sheet molding, blow molding, injection blow molding, blow molding, extrusion molding, foam molding, and casting molding. It can also be formed using two-stage molding methods such as pressure molding and vacuum molding. Extrusion molding and casting molding are preferred. In this case, for example, an extruder equipped with a T-die, a circular die, etc., can be used to extrude the unstretched film. When obtaining the molded product by extrusion molding, a material in which various resin components and additives have been pre-melted and mixed can be used, or molding can be performed by melt mixing during extrusion molding. Alternatively, a solvent common to various resin components, such as chloroform or dichloromethane, can be used to dissolve the various resin components, followed by casting, drying, and curing, thereby casting the unstretched film.

[0083] For the aforementioned polymer stretch film, the formed film can be uniaxially stretched along the machine flow direction (MD; Mechanical Direction, longitudinal or length direction) or along the direction perpendicular to the machine flow direction (TD; Transverse Direction, transverse or width direction). Alternatively, biaxial stretch film can be manufactured by stretching using methods such as successive biaxial stretching with roller stretching and tenter frame stretching, simultaneous biaxial stretching based on tenter frame stretching, and biaxial stretching based on tubular stretching.

[0084] The aforementioned liquid crystal polymer film may contain a reactive liquid crystal compound in a polymerized state. The same applies to the reactive liquid crystal compound described above for the coated polarizer.

[0085] In one or more embodiments, the thickness of the phase difference adjustment layer 203 may be 10 μm to 100 μm when it is a polymer stretching film, and 0.1 μm to 5 μm when it is a liquid crystal polymer film.

[0086] The aforementioned refractive index adjustment layer 204 is provided to compensate for the refractive index difference in the dimming layer stack caused by the aforementioned transparent conductive layer, and can improve visibility characteristics by reducing the refractive index difference. Additionally, the aforementioned refractive index adjustment layer 204 can also be provided to correct the color caused by the aforementioned transparent conductive layer. On the other hand, when the aforementioned transparent conductive layer has a pattern, the aforementioned refractive index adjustment layer 204 can compensate for the transmittance difference between the patterned areas and the unpatterned areas.

[0087] Specifically, when the aforementioned transparent conductive layer is stacked adjacent to other components with different refractive indices (such as polarizer 201), the difference in refractive index with the adjacent layers can induce differences in light transmittance. This can be especially problematic when the transparent conductive layer is patterned, potentially causing a difference between patterned and unpatterned areas. Therefore, by including the aforementioned refractive index adjustment layer 204, the difference in light transmittance of the dimming stack can be reduced, particularly when the transparent conductive layer is patterned, preventing a difference between patterned and unpatterned areas.

[0088] In one embodiment, in addition to the functional layers described above, the polarizing plate may also include other functional layers to assist or enhance the characteristics of the polarizer. For example, to further improve mechanical durability, it may also include an outer coating layer.

[0089] The first and second polarizing plates of the present invention may each independently include a hard coating layer (not shown). As an example, the hard coating layer may be formed on one side of the polarizing plate, and more preferably, it may be located between the polarizing plate and the transparent conductive layer. The hard coating layer can be formed by applying a hard coating forming composition to another component and then curing it by light or heat. In this case, the hard coating forming composition is not particularly limited; for example, it may contain a photocurable compound and a photoinitiator.

[0090] The aforementioned photocurable compounds and photoinitiators can be made from substances commonly used in the art without limitation. For example, the aforementioned photocurable compounds can include photopolymerizable monomers, photopolymerizable oligomers, etc., such as monofunctional and / or polyfunctional (meth)acrylates. The photoinitiators can include hydroxycyclohexylphenyl ketone, trimethylbenzoyl diphenylphosphine oxide, acetophenone series, oxime ester series, etc. Commercially available products include Irgacure-184, TPO, Irgacure-907, etc.

[0091] Furthermore, in this invention, the aforementioned hard coating may contain inorganic fillers. Specifically, when the aforementioned hard coating composition contains inorganic fillers, better hardness can be obtained, and by adjusting the thickness of the hard coating, the physical properties of the polarizer-transparent conductive layer laminate can also be improved, which is therefore preferred. As the inorganic filler used in this case, silica particles with an average particle size of 20 nm or less are particularly preferred. There are no limitations on the silica particles used in the manufacturing process, but it is preferable to use water-dispersed or organic solvent-dispersed colloidal silica sol. By including inorganic fillers that meet the above conditions, the polarizer having the aforementioned hard coating can ensure sufficient hardness and prevent curling. When the average particle size of the silica particles is greater than 20 nm, the transparency of the dimming laminate will decrease or the surface condition will deteriorate.

[0092] As specific examples, commercially available products that disperse silica sol include the PURISOL-O series (manufactured by GEMATECH), the CATALOID-S series (manufactured by Catalyst Chemical Industry), and the YGS series (manufactured by YOUNG IL CHMICAL).

[0093] The aforementioned hard coating can be formed with a thickness of 3 to 25 μm. When the hard coating is formed on the polarizing plate within the above range, it is advantageous to ensure mechanical properties and maintain a thinner dimming laminate because the thickness satisfies the requirement of imparting appropriate Martens hardness and elastic recovery rate to the polarizing plate-conductive layer laminate containing the polarizing plate. If the thickness is less than 3 μm, the hardness may be insufficient and the Martens hardness may not be achieved. If the thickness is greater than 25 μm, not only will the amount of resin used to form the hard coating increase, leading to increased manufacturing costs, but damage such as wrinkles may also occur, and the elastic recovery rate will decrease. In particular, if one or more of the first or second laminates contains a hard coating with a thickness exceeding the above range, the dimming laminate containing the first and second laminates may develop black spots, curling, or poor drive on the side containing the hard coating.

[0094] The dimming laminate of the present invention may also include other components without prejudice to the purpose of the present invention, for example, it may also include one or more of an adhesive / bonding layer and an ultraviolet absorption layer.

[0095] The aforementioned ultraviolet (UV) absorbing layer is not particularly limited as long as it is used to prevent the degradation of the dimming laminate caused by UV radiation. For example, salicylic acid-based UV absorbers (phenyl salicylate, p-tert-butyl salicylate, etc.), benzophenone-based UV absorbers (2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, etc.), and benzotriazole-based UV absorbers (2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole, ... 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-(3",4",5",6"-tetrahydrophthalimidemethyl)-5'-methylphenyl)benzotriazole, 2,2-methylenebis(4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol), 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'- Hydroxy-3'-tert-butyl-5'-(2-octoxycarbonylethyl)-phenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-(1-methyl-1-phenylethyl)-5'-(1,1,3,3-tetramethylbutyl)-phenyl)benzotriazole, 2-(2H-benzotriazol-2-yl)-6-(linear and side-chain dodecyl)-4-methylphenol, octyl-3-[3-tert-butyl-4-hydroxy-5-(chloro-2H-benzotriazol-2-yl)phenyl]propionate, and 2-ethylhexyl-3-[3-tert-butyl-4-hydroxy] Mixtures of 5-(5-chloro-2H-benzotriazole-2-yl)phenyl]propionate, etc.), cyanoacrylate-based UV absorbers (2'-ethylhexyl-2-cyano-3,3-diphenyl acrylate, ethyl-2-cyano-3-(3',4'-methylenedioxyphenyl)-acrylate, etc.), triazine-based UV absorbers, etc., preferably benzotriazole-based or triazine-based UV absorbers with high transparency and excellent effect in preventing the deterioration of polarizing plates or layers, and especially preferably benzotriazole-based UV absorbers with more suitable spectroscopic absorption spectra. The aforementioned benzotriazole-based ultraviolet absorbers can also be bis(Bis)-substituted substances, such as 6,6'-methylenebis(2-(2H-benzo[d][1,2,3]triazol-2-yl)-4-(2,4,4-trimethylpentane-2-yl)phenol, 6,6'-methylenebis(2-(2H-benzo[d][1,2,3]triazol-2-yl)-4-(2-hydroxyethyl)phenol, etc.

[0096] Transparent conductive layers 310, 320

[0097] The aforementioned transparent conductive layers 310 and 320 are provided for driving the liquid crystal layer 400. At least one of the first and second transparent conductive layers can be formed to be in direct contact with the first or second polarizing plate without a separate substrate. In this case, it is possible to manufacture a dimming laminate that maintains the optical characteristics of the first and second polarizing plates while being thin.

[0098] For example, such as Figure 1 As shown in the figure, the first transparent conductive layer 310 can be formed in direct contact with the first polarizing plate 210, and the second transparent conductive layer 320 can be formed in direct contact with the second polarizing plate 220.

[0099] Conventional dimming laminates used in manufacturing smart windows and similar products are manufactured by forming a conductive layer for driving liquid crystals on one side of a substrate and bonding the other side of the substrate to a polarizing plate. However, the dimming laminate of the present invention is characterized by forming a conductive layer directly on one side of the polarizing plate without intentionally including a separate substrate for forming the conductive layer, thereby reducing the thickness of the laminate and improving transmittance and bending characteristics in the light transmission mode.

[0100] In one embodiment, the first transparent conductive layer 310 and / or the second transparent conductive layer 320, which are formed in direct contact with at least one of the first polarizing plate 210 and the second polarizing plate 220, are formed on the polarizing plates by sharing a contact surface with the first polarizing plate 210 and / or the second polarizing plate 220 without including a separate substrate. For example, the first transparent conductive layer 310 and / or the second transparent conductive layer 320 can be formed by vapor deposition on the upper surface of the coating formed on the first polarizing plate 210 and / or the second transparent conductive layer 220. In this case, in order to improve the adhesion between the first transparent conductive layer 310 and / or the second transparent conductive layer 320 and at least one of the first polarizing plate 210 and the second polarizing plate 220, a pretreatment such as corona treatment or plasma treatment can be performed on one side of the polarizing plate before direct contact with the pretreated side of the polarizing plate. The pretreatment is not limited to corona treatment or plasma treatment, and conventional or future pretreatment processes can be used within the scope of the present invention without prejudice to the purpose of the present invention.

[0101] In another embodiment of the present invention, the first transparent conductive layer 310 and / or the second transparent conductive layer 320, which are formed in direct contact with at least one of the first polarizing plate 210 and the second polarizing plate 220, can be formed in direct contact with the polarizing plate through an easy-to-adhere layer (not shown for convenience) disposed on one side of the polarizing plate to improve the adhesion to the polarizing plate. The easy-to-adhere layer can use conventionally or subsequently developed adhesives. In one or more embodiments, acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, polyvinyl alcohol adhesives, polyvinylpyrrolidone adhesives, polyacrylamide adhesives, cellulose adhesives, vinyl alkyl ether adhesives, etc., can be used. There are no particular limitations on the adhesive as long as it has adhesive strength and viscoelasticity, but from the perspective of ease of acquisition, acrylic adhesives are preferred. For example, they may contain (meth)acrylate copolymers, crosslinking agents, and solvents.

[0102] As a method for vapor-depositing and coating the aforementioned transparent conductive layer onto one side of the aforementioned polarizing plate, it can be formed by methods commonly used in the art. For example, appropriate processes can be selected from coating processes such as spin coating, roll coating, bar coating, dip coating, gravure coating, curtain coating, mold coating, spray coating, scraping coating, and kneading machine coating; printing (coating) processes such as screen printing, spray printing, inkjet printing, letterpress printing, gravure printing, and lithography; and vapor deposition processes such as chemical vapor deposition (CVD), physical vapor deposition (PVD), and plasma-enhanced chemical vapor deposition (PECVD).

[0103] In the dimming laminate of the present invention, at least one of the first transparent conductive layer 310 and the second transparent conductive layer 320 may contain one or more of the following: transparent conductive oxide, metal, carbon-based material, conductive polymer, conductive ink and nanowire, but is not limited thereto, and materials of transparent conductive layers developed in the past or in the future may be used.

[0104] In one or more embodiments, the transparent conductive oxide may comprise one or more of the following selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (IZTO), zinc aluminum oxide (AZO), zinc gallium oxide (GZO), tin fluoride oxide (FTO), and zinc oxide (ZnO).

[0105] In addition, the aforementioned metal may include one or more of the group consisting of gold (Au), silver (Ag), copper (Cu), aluminum (Al), platinum (Pt), palladium (Pd), chromium (Cr), titanium (Ti), tungsten (W), niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), and alloys containing at least one of them. For example, it may include silver-palladium-copper (APC) alloy or copper-calcium (CuCa) alloy.

[0106] The aforementioned carbon-based materials may include one or more of the group consisting of carbon nanotubes (CNTs) and graphene.

[0107] The aforementioned conductive polymers can be any conductive polymers developed previously or in the future, for example, they may include those selected from polythiophene, poly(3,4-ethylenedioxythiophene), polyaniline, polyacetylene, polydiacetylene, polyphenylene, polyphenylene vinylene, polyphenylene sulfide, polythienylene vinylene, and polythiophene vinylene. Polyvinylene, polyfluorene, polypyrrole, poly(3,4-ethylenedioxythiophene):polystyrenesulfonate, poly(3,4-ethylenedioxythiophene):camphorsulfonic acid, poly(3,4-ethylenedioxythiophene):toluenesulfonic acid, poly(3,4-ethylenedioxythiophene):dodecylbenzenesulfonic acid, polyaniline:polystyrenesulfonate, polyaniline:camphorsulfonic acid, polypyrrole:polystyrenesulfonate, polypyrrole:camphorsulfonic acid, polypyrrole:toluenesulfonic acid, polypyrrole:dodecylbenzenesulfonic acid, polythiophene:polystyrenesulfonate, polythiophene:camphorsulfonic acid, polythiophene:toluenesulfonic acid, and polythiophene:dodecylbenzenesulfonic acid polymers are all grouped together. Since conductive polymers do not generate relatively high temperatures during vapor deposition, deformation of the polarizing plate during the process can be prevented. Therefore, conductive polymers that can be molded at relatively low temperatures are particularly preferred.

[0108] The conductive ink mentioned above can be an ink made by mixing metal powder and curable polymer binder, and the nanowires can be, for example, silver nanowires (AgNW).

[0109] Furthermore, the first transparent conductive layer 310 and the second transparent conductive layer 320 can be formed by combining the aforementioned materials into a structure of two or more layers. For example, in order to reduce the reflectivity of incident light and increase the transmittance, they can be formed into a two-layer structure comprising a metal layer and a transparent conductive oxide layer.

[0110] In one embodiment, the transparent conductive layer may have a thickness of 5 μm or less, preferably 3 μm or less. In this case, the transparent conductive layer ensures both the predetermined transmittance and robust compressibility, allowing the fabrication of a thinner dimming laminate. Furthermore, a thinner thickness improves the composite's hardness and elastic recovery rate.

[0111] Liquid crystal layer

[0112] The liquid crystal layer 400 can adjust the transmittance of light incident from one or more directions according to the electric field generated by the transparent conductive layer, thereby changing the driving mode of the dimming stack to a light-transmitting mode or a light-blocking mode.

[0113] There are no particular limitations on the liquid crystal compound mentioned above, as long as it can be driven by an electric field and the light transmittance can be controlled. Liquid crystal compounds that have been developed in the past or in the future can be used. For example, the content regarding the reactive liquid crystal compound for the above-mentioned coated polarizer can be applied in the same way.

[0114] There are no particular limitations on the liquid crystal behavior of the aforementioned liquid crystal layer 400. For example, it can use twisted nematic (TN) mode, super twisted nematic (STN) mode, in-plane switching (IPS) mode, fringe-field switching (FFS) mode, electrically controlled birefringence (ECB) mode, and vertical alignment (VA) mode. From the perspective of controlling light transmittance, it is preferable to use twisted nematic (TN) mode.

[0115] In another embodiment of the present invention, the liquid crystal layer 400 may further include a sealant layer formed on its periphery. This sealant layer is used to bond two different polarizing plate-transparent conductive layer laminates and may be located in a non-active region.

[0116] The dimming laminate of the present invention may also include other components without prejudice to the purpose of the present invention, such as glass, ultraviolet absorbing layer and adhesive / bonding layer.

[0117] An example of the present invention referring to the above-described dimming laminate is as follows: Figure 3a The above Figure 1The dimming laminate shown may further include a first glass 110 at the periphery of the first laminate, and a second glass 120 at the periphery of the second laminate. The first and / or second glass may possess durability against external impacts and transparency visible to the user, and may also contain glass materials that achieve flexible properties. For example, the first and second glass may each comprise glass, ceramics, quartz, borosilicate, aluminosilicate, alkali-free glass, soda-lime glass, grid glass, colored glass, magic mirror, and oxide glasses such as holographic glass, silicate glass, borosilicate glass, and phosphate glass.

[0118] At this time, a first bonding layer may be included between the first laminate and the first glass, and / or a second bonding layer may be included between the second laminate and the second glass. Specifically, when the dimming laminate of the present invention is applied to a smart window, such as... Figure 3a As shown, only by bonding the polarizing plate to the glass without wrinkles or warping can this phenomenon be avoided. Figure 3b The bubbles and black spots shown are a concern. Therefore, to prevent potential defects in appearance during the process, it is necessary not only to limit the thermal stress of the polarizing plate, but also to have a suitable bonding layer that can tightly bond the polarizing plate to the glass.

[0119] The aforementioned bonding layer can be formed from an adhesive composition comprising an acrylic random copolymer and an tackifier. Any substance that exhibits thermal and chemical stability after curing, such as a UV-curing resin or a thermosetting resin, can be used as the bonding layer. As an example, when the resin is contained in the form of a sealant, components commonly used in this art can be used, such as acrylate-based, epoxy-based, urethane-based, and phenolic resins, and resins developed in the future can also be used. In particular, polyvinyl butyral (PVB) or ethylene vinyl acetate (EVA) is preferred. Using PVB or EVA is preferable from the perspective of ensuring the stability of the bonding layer under high temperature and high pressure conditions.

[0120] The aforementioned acrylic random copolymers may contain monomers commonly used in the technical field to which this invention pertains, without reducing elasticity and adhesion.

[0121] The method for manufacturing the above-mentioned acrylic random copolymer is not particularly limited. For example, methods commonly used in the technical field of this invention, such as bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, and UV polymerization, can be used, with solution polymerization or UV polymerization being preferred.

[0122] The aforementioned tackifier can be added together with the aforementioned acrylic random copolymer to improve the adhesion and tackiness of the bonding layer formed by the adhesive composition.

[0123] The above-described bonding layer composition may further include additives to improve coatability, adhesion, etc., as needed by those skilled in the art, without prejudice to the purpose of the invention. For this purpose, it may further include ingredients commonly used in the art, such as surfactants, silane coupling agents, antioxidants, UV absorbers, and / or anti-caking agents. These may be used individually or in combination or in any ratio.

[0124] The thickness of the aforementioned bonding layer can be from 5 to 80 μm. If the thickness of the bonding layer is within the aforementioned range, the adhesion and fixing force are excellent, thus preventing the polarizer from shrinking.

[0125] Smart windows, automotive and building windows

[0126] In addition to the aforementioned dimming laminate, the present invention also includes a smart window incorporating the aforementioned dimming laminate. In particular, the dimming laminate of the present invention, by defining the Martens hardness and elastic recovery rate of the polarizing plate-transparent conductive layer laminate located above or below the liquid crystal layer, possesses the excellent advantage of being able to manufacture a dimming laminate free of bubbles and black spots and with smooth operation, particularly suitable for dimming laminates of smart windows.

[0127] Hereinafter, specific embodiments of the present invention are described. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in a variety of different ways. These embodiments are provided only to make the disclosure of the present invention complete, and to fully inform those skilled in the art of the scope of the invention. The present invention is defined only by the scope of the claims.

[0128] Manufacturing Example 1: Polarizing Plate Production

[0129] (1) Swelling treatment process

[0130] A 60 μm thick polyvinyl alcohol film (raw material film) (manufactured by Kuraray Co., Ltd., trade name "Kuraraypoval film VF-PE#6000", average degree of polymerization 2400, degree of saponification 99.9 mol%) is continuously unwound from the raw material roll and immersed in a swelling bath containing pure water at 20°C for 30 seconds. In this swelling process, inter-roll stretching (longitudinal uniaxial stretching) is performed by creating a circumferential speed difference between the pinch rolls. The stretching ratio based on the raw material film is 2.5 times.

[0131] (2) Dyeing process

[0132] Next, the film passing through the pinch rollers is immersed in a dyeing bath for 120 seconds. In this dyeing process, inter-roll stretching (longitudinal uniaxial stretching) is also performed by creating a circumferential speed difference between the pinch rollers. The stretching ratio is 1.1 times based on the film after the swelling treatment process.

[0133] (3) Crosslinking process

[0134] Next, the film passing through the clamping rollers is immersed in a first crosslinking bath at 56°C for 70 seconds. Inter-roll stretching (longitudinal uniaxial stretching) is performed by creating a circumferential speed difference between the clamping rollers and the clamping rollers positioned between the first and second crosslinking baths. The stretching ratio is 1.9 times based on the film after the dyeing process.

[0135] (4) Color matching process

[0136] Next, the crosslinked membrane was immersed in a second crosslinking bath at 40°C for 10 seconds.

[0137] (5) Cleaning process

[0138] Next, the membrane after the second crosslinking treatment was immersed in a washing bath containing pure water at 14°C for 5 seconds, and then rinsed at a flow rate of 5 mg / L. 3 Cleaning is performed at a rate of / h and a rinsing temperature of 14℃.

[0139] (6) Drying process

[0140] Next, the film after the cleaning process is passed through a drying oven and dried at 80°C for 190 seconds to produce a polarizer film. The moisture content after drying is 13.6%, and the thickness of the obtained polarizer film is approximately 21 μm.

[0141] (7) Joining process

[0142] Next, an aqueous adhesive containing 5 parts by mass of polyvinyl alcohol relative to 100 parts by mass of water was prepared as an adhesive. Then, triacetyl cellulose (TAC) films (40 μm thick) were laminated on both sides of the aforementioned polarizer film using the prepared UV adhesive as first and second protective films. The obtained laminate was subjected to UV exposure to cure the adhesive and produce a polarizing plate. The adhesive layer in the obtained polarizing plate has a thickness of approximately 2 μm. The thickness and type of the protective films constituting the polarizing plate are shown in Table 1 below.

[0143] Manufacturing Example 2-1: Preparation of a Hard Coating Composition Containing Inorganic Fillers

[0144] 15 parts by weight of pentaerythritol triacrylate as a photocurable resin, 30 parts by weight of propylene glycol monomethyl ether dispersed reactive silica sol (average particle size 15 nm, solid content 40%), 2.7 parts by weight of 1-hydroxy-cyclohexyl-phenyl-one as a photoinitiator, 52 parts by weight of propylene glycol monomethyl ether as a solvent, and 0.3 parts by weight of BYK-UV3570 (BYK) as a leveling agent were mixed in a mixer and then filtered using a PP filter to produce a hard coating composition.

[0145] Manufacturing Example 2-2: Preparation of a Hard Coating Composition Without Inorganic Fillers

[0146] 35 parts by weight of hexafunctional acrylate (PU620D, Meiyuan Special Chemicals) as a light-curing resin, 10 parts by weight of hexanediol diacrylate, 2.7 parts by weight of 1-hydroxy-cyclohexyl-phenyl-one as a photoinitiator, 52 parts by weight of propylene glycol monomethyl ether as a solvent, and 0.3 parts by weight of BYK-UV3570 (BYK) as a leveling agent were mixed in a mixer and then filtered using a PP filter to produce a hard coating composition.

[0147] Manufacturing Example 3: Fabrication of a Transparent Conductive Layer (PEDOT)

[0148] The transparent conductive layer is manufactured by mixing conductive polymer solution 1 and solution 2 in a 1:1 ratio. Solution 1 uses a mixture of 60 wt% vinylbenzenesulfonic acid homopolymer compound and 2,3-dihydrothieno[3,4-b]-1,4-dioxin homopolymer (aqueous), 20 wt% ethanol, and 20 wt% deionized water relative to the total weight of solution 1. Solution 2 uses a mixture of 1.0 wt% polyester resin (25% solids, aqueous), 75 wt% ethanol, and 24 wt% deionized water relative to the total weight of solution 2.

[0149] Examples and Comparative Examples: Fabrication of Polarizing Plate-Transparent Conductive Layer Laminate

[0150] A first laminate is manufactured, comprising a first polarizing plate manufactured according to Manufacturing Example 1, a hard coating composition manufactured according to Manufacturing Example 2 applied to the first polarizing plate, solvent drying and UV irradiation under a nitrogen atmosphere to form a hard coating layer, and a first transparent conductive layer manufactured according to Manufacturing Example 3. A second laminate is manufactured in the same manner as the first laminate. The configurations of the embodiments and comparative examples are shown in Table 1 below.

[0151] [Table 1]

[0152]

[0153]

[0154]

[0155] -TAC membrane: Triacetyl Cellulose, Fuji Corporation

[0156] -PVA film: Polyvinyl alcohol

[0157] - Containing inorganic filler HC: Hard coating composition manufactured according to Manufacturing Example 2-1

[0158] - Free of inorganic fillers HC: Hard coating composition manufactured according to Manufacturing Example 2-2

[0159] -PEDOT: A transparent conductive layer manufactured according to Manufacturing Example 3

[0160] Experimental examples: Evaluation of compressibility properties and evaluation of process defects

[0161] (1) Martens hardness determination of the first and second laminates

[0162] For the polarizing plate-transparent conductive layer laminate manufactured according to Table 1 above, the indentation test sequence and method specified in ISO 14577 were performed. A nanoindenter (FISHER, HM500) was used as the testing machine, with a pyramidal diamond indenter having a square base and an angle of 136° between the opposing faces. Specifically, in the test method, the laminates of the examples and comparative examples were fixed onto several hundred μm thick soda-lime glass using an adhesive with a thickness of approximately 5 μm. The load application and removal times were each set to 15 seconds for evaluation. The test temperature was set to 23°C, and the martensitic hardness (MPa) was measured using the nanoindenter when the indenter was pressed into the surface of the polarizing plate-transparent conductive layer laminate at a constant speed and a load of 1 mN was applied for 15 seconds. The results are shown in Table 2. Martens hardness is the value obtained by dividing by the surface area of ​​the indenter that penetrates beyond the zero point of contact, as shown in Equation 1 below, calculated by dividing the test load F by the surface area As penetrated by the indenter from the zero point of contact.

[0163] <Formula 1>

[0164] Martens hardness (MPa) = F / As

[0165] (2) Determination of elastic recovery rate of the first and second laminates

[0166] For the polarizing plate-transparent conductive layer laminate manufactured according to Table 1 above, the elastic recovery rate (nIT) was measured using a nanoindenter (Fischer, HM500), and the results are shown in Table 2 below. Specifically, a 1mN load was applied to the substrate surface of the polarizing plate for 15 seconds using an indenter with a triangular pyramidal tip (Vickers tip), and the elastic recovery rate (%) was measured using the nanoindenter and is shown in Table 2.

[0167] (3) Evaluation of process defects in dimming laminate

[0168] On each transparent conductive layer of the first and second laminates manufactured above, a sealant applicator (SHOTmini 200Ωx, Musashi Corporation) is applied using a sealant applicator and a pointed needle (SPN-0.25-12.7L) at a discharge pressure of 200 mPa according to the product dimension drawing. Then, liquid crystal driven in a twisted nematic (TN) mode is injected onto the alignment film using an ODF process. Next, with the transmission axes of the first and second polarizing plates at 90° to each other and the machine orientation (MD) parallel to each other (0°) in the top view, a sealant is applied at a pressure of 3 kg / cm². 2 Pressure bonding, followed by UV curing along the sealant line (500mJ / cm). 2 ).

[0169] The driving results of the produced dimming laminate were visually observed. Appearance defects such as bubbles and black spots, as well as the driving performance of the process, were evaluated, as shown in Table 2 below.

[0170] <Evaluation Criteria>

[0171] -Excellent: No black marks, driver works correctly.

[0172] - Black dot defect: Black dots are present, indicating a driver malfunction.

[0173] - Curl defect: Curl occurs during bonding.

[0174] [Table 2]

[0175]

[0176]

[0177] by Figure 2 The polarizing plate-transparent conductive layer laminate shown is used as the object. The martensitic hardness (HM) and elastic recovery rate (nIT) were measured and are shown in Table 2. It was confirmed that the martensitic hardness of both the first and second laminates meets 100 N / mm².2 The above 430N / mm 2 In Examples 1 to 6, where a polarizing plate-transparent conductive layer laminate with an elastic recovery rate (nIT) of 40% to 87% was used to manufacture the dimming laminate, no bubbles or black spots were observed to the naked eye, the drive was smooth, and no process defects occurred. On the other hand, it was confirmed that, as in Comparative Examples 1 to 9, even if the martensitic hardness of one of the first and second laminates included in the dimming laminate did not meet 100 N / mm, 2 The above 430N / mm 2 If the following conditions are met, or if the elastic recovery rate (nIT) is not above 40% or below 87%, it will also be unusable as a dimming overlay included in a smart window due to poor appearance and unsmooth operation.

Claims

1. A light-adjustable laminate comprising: a first laminate comprising a first polarizing plate and a first transparent conductive layer; a second laminate opposite to the first laminate and comprising a second polarizing plate and a second transparent conductive layer; and a liquid crystal layer disposed between the first and second laminates. The Martens hardness HM of each of the first and second laminates when using a nanoindenter and applying a pressing load of 1 mN for 15 seconds is 100 N / mm 2 The above 430 N / mm 2 Hereinafter, the elastic recovery rate nIT is 40% or more and 87% or less.

2. The light-adjustable laminate according to claim 1, wherein the first and second polarizing plates each independently have a thickness of 30 to 300 μm.

3. The light-adjustable laminate according to claim 1, wherein the first and second laminates each independently comprise a hard coat layer, the hard coat layer is formed with a thickness of 3 to 25 μm and comprises an inorganic filler.

4. The light-adjustable laminate according to claim 3, wherein the inorganic filler comprises silica particles having an average particle diameter of 20 nm or less.

5. The light-adjustable laminate according to claim 1, further comprising a first glass at a peripheral portion of the first laminate, further comprising a second glass at a peripheral portion of the second laminate.

6. The light-adjustable laminate according to claim 4, further comprising a first bonding layer between the first laminate and the first glass, further comprising a second bonding layer between the second laminate and the second glass, the bonding layer is one or more selected from the group consisting of polyvinyl butyral (PVB) and ethylene-vinyl acetate (EVA).

7. The light-adjustable laminate according to any one of claims 1 to 6, wherein at least one of the first and second transparent conductive layers is formed so as to directly contact without comprising a separate substrate therebetween.

8. The light-adjustable laminate according to any one of claims 1 to 6, wherein at least one of the first and second polarizing plates comprises one or more functional layers selected from the group consisting of a protective layer, a phase difference adjusting layer, and a refractive index adjusting layer.

9. A smart window comprising the light-adjustable laminate according to any one of claims 1 to 8.

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