Light control laminate, smart window including the same, and automobile or fittings for building applied with the same

Abstract

SOLUTION: A light control laminate includes: a first polarizing plate; a first transparent conductive layer formed on one surface of the first polarizing plate; a second polarizing plate facing the first polarizing plate; a second transparent conductive layer formed on one surface of the second polarizing plate, and facing the first transparent conductive layer; and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer. At least one of the first polarizing plate and the second polarizing plate has S calculated by the formula 1 of 0.5-4.0 N mm.EFFECT: A light control laminate that is easily handled and not damaged during transport and can be joined to a smart window without occurrence of a defect, a smart window including the same, and an automobile or fittings for a building applied with the same, can be provided.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a light-control laminate, a smart window including the light-control laminate, and a fitting for an automobile or building to which the light-control laminate is applied. [Background technology]

[0002] Generally, external light blocking coatings are applied to the glass windows of vehicles such as cars. However, conventional glass windows of vehicles have a fixed transmittance, and external light blocking coatings also have a fixed transmittance.

[0003] Therefore, the overall transmittance of such conventional vehicle windows is fixed, which can lead to accidents. For example, if the overall transmittance is set low, there is no problem during the day when there is sufficient light in the surroundings. However, there is a problem that drivers have difficulty properly checking the surroundings of the vehicle when there is insufficient light in the surroundings, such as at night. Alternatively, if the overall transmittance is set high, there is a problem that drivers may experience glare during the day when there is sufficient light in the surroundings. For this reason, a light-control laminate has been developed that can change light transmittance when voltage is applied.

[0004] The light-control laminate is driven by applying a voltage to drive the liquid crystal and change the transmittance. The light-control laminates developed to date are manufactured by forming a conductive layer for driving the liquid crystal on a separate substrate and combining it with other elements such as a polarizer.

[0005] For example, Japanese Patent Application Laid-Open No. 2018-010035 also discloses a light-control laminate including a transparent electrode layer formed on a polycarbonate (PC) substrate or the like having a predetermined thickness.

[0006] However, when a separate substrate is used to form the conductive layer, the manufacturing process becomes complicated, which increases manufacturing costs, and the thickness of the laminate increases, which causes a phase difference, resulting in changes in transmittance.

[0007] On the other hand, when a polarizer used in conventional image display devices such as LCDs is applied to a smart window, there is a risk that the polarizer may be easily warped during transportation due to the absence of a supporting substrate, resulting in bending and breakage. In addition, when the polarizer is bonded to the smart window, there are problems such as defects such as lifting and pressing due to bonding pressure.

[0008] Therefore, it is necessary to develop a light-control laminate that is free from the risk of breakage during transportation and that does not cause defects when bonded to a smart window. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2018-010035 Summary of the Invention [Problem to be solved by the invention]

[0010] An object of the present invention is to provide a light-control laminate that does not require a separate substrate for forming a conductive layer, thereby simplifying the manufacturing process.

[0011] Another object of the present invention is to provide a light-control laminate that is easy to handle, is free from the risk of breakage during transportation, and prevents defects from occurring when it is bonded to a smart window.

[0012] Another object of the present invention is to provide a smart window including the light-control laminate and a fitting for an automobile or building to which the smart window is applied.

[0013] However, the problems to be solved by the present invention are not limited to those mentioned above, and other problems not mentioned above will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0014] The present invention relates to a light-control laminate including a first polarizer; a first transparent conductive layer formed on one side of the first polarizer; a second polarizer facing the first polarizer; a second transparent conductive layer formed on one side of the second polarizer and facing the first transparent conductive layer; and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer, wherein at least one of the first polarizer and the second polarizer has an S of 0.5 to 4.0 N mm as calculated by the following Equation 1:

[0015]

number

[0016] (In the above formula 1, E is the elastic modulus (N / mm 2 ), t is the thickness (mm) and ν is the Poisson's ratio. 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 retardation adjusting layer, and a refractive index adjusting layer.

[0017] At least one of the first and second polarizing plates may have a thickness of 50 to 300 μm.

[0018] At least one of the first transparent conductive layer and the second transparent conductive layer may be formed in direct contact with the first polarizer or the second polarizer without a separate substrate between them.

[0019] At least one of the first transparent conductive layer and the second transparent conductive layer may be formed in direct contact with the first polarizing plate or the second polarizing plate, including an easy-adhesion layer between the transparent conductive layer and the first polarizing plate or the second polarizing plate.

[0020] At least one of the first and second transparent conductive layers may include at least one selected from the group consisting of transparent conductive oxides, metals, carbon-based materials, conductive polymers, conductive inks, and nanowires.

[0021] The liquid crystal behavior mode of the liquid crystal layer may be any one selected from the group consisting of TN (Twisted nematic) mode, STN (Super twisted nematic) mode, IPS (In-plane switching) mode, FFS (Fringe-field switching) mode, and VA (Vertical alignment) mode.

[0022] The liquid crystal behavior mode of the liquid crystal layer may be a TN (Twisted Nematic) mode.

[0023] The liquid crystal layer may include a cured product of a liquid crystal layer-forming composition that includes a polymerizable monomer and a liquid crystal compound.

[0024] The liquid crystal layer may include a polymer network and a liquid crystal compound. The light-controlling laminate may further include one or more layers selected from the group consisting of an adhesive layer, an ultraviolet absorbing layer, and a hard coating layer.

[0025] The present invention also relates to a smart window comprising the light control laminate. The present invention also relates to a vehicle in which the smart window is applied to at least one of a front window, a rear window, a side window, a sunroof window, and an interior partition.

[0026] The present invention also relates to building fixtures including the smart window. [Effects of the Invention]

[0027] According to the photochromic laminate of the present invention, a conductive layer is formed directly on one side of a polarizer, and a separate substrate for forming the conductive layer is not required, thereby significantly reducing the thickness compared to conventional photochromic laminates.

[0028] Furthermore, the light-control laminate according to the present invention is easy to handle and is not susceptible to damage during transportation, and defects can be prevented from occurring when it is bonded to a smart window.

[0029] The present invention also provides a smart window including the light-control laminate and a fitting for an automobile or building to which the smart window is applied. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 is a diagram showing the layer structure of a light-control laminate according to one embodiment of the present invention. [Figure 2a] FIG. 2a is a diagram showing a stack structure of a polarizer according to one or more embodiments of the present invention. [Figure 2b] FIG. 2b is a diagram showing a stack structure of a polarizer according to one or more embodiments of the present invention. [Figure 2c] FIG. 2c shows a stack structure of a polarizer according to one or more embodiments of the present invention. [Figure 2d] FIG. 2d shows a stack structure of a polarizer according to one or more embodiments of the present invention. [Figure 2e] FIG. 2e is a diagram illustrating a stack structure of a polarizer according to one or more embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0031] The present invention relates to a light-control laminate including a first polarizer; a first transparent conductive layer formed on one side of the first polarizer; a second polarizer facing the first polarizer; a second transparent conductive layer formed on one side of the second polarizer and facing the first transparent conductive layer; and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer, wherein at least one of the first polarizer and the second polarizer has an S of 0.5 to 4.0 N mm as calculated by the following Equation 1:

[0032]

number

[0033] (In the above formula 1, E is the elastic modulus (N / mm 2 ), t is the thickness (mm) and ν is the Poisson's ratio. The light-control laminate of the present invention is particularly suitable for technical fields in which light transmittance can be changed by applying a voltage, and can be used, for example, in smart windows.

[0034] A smart window is an optical structure that controls the amount of light or heat passing through by changing its light transmittance in response to the application of an electrical signal. That is, a smart window can be changed between transparent, opaque, or translucent depending on the voltage applied, and is also called variable transmittance glass, light-control glass, or smart glass.

[0035] Smart windows can be used to divide the interior space of vehicles and buildings or as partitions for privacy, or as light windows placed in openings in buildings. They can also be used for highway signs, bulletin boards, odometers, clocks, or advertising screens, and can be used to replace glass in vehicles such as windows or sunroofs in automobiles, buses, airplanes, ships, or trains.

[0036] The light-control laminate of the present invention can also be used in smart windows in the various technical fields mentioned above, but since the conductive layer is formed directly on the polarizer and therefore does not require a separate substrate for forming the conductive layer, it is thin and has advantageous 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 light-control laminate of the present invention can be used in transportation, for example, the front window, rear window, side window, and sunroof window of an automobile, or building fixtures, and can be used not only for blocking external light but also for dividing the interior space of an automobile or building, such as an interior partition, or for privacy protection.

[0037] Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. However, the following drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and, together with the above-described invention content, serve to further understand the technical concept of the present invention, and therefore the present invention should not be interpreted as being limited only to the matters depicted in these drawings.

[0038] The terms used herein are for the purpose of describing the embodiments and are not intended to limit the present invention. In this specification, the singular form includes the plural form unless otherwise specified in the phrase. For example, the term "polarizer" used herein may refer to at least one polarizer of the first polarizer and the second polarizer, and the term "transparent conductive layer" may refer to at least one transparent conductive layer of the first transparent conductive layer and the second transparent conductive layer.

[0039] As used herein, the terms "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components, steps, operations and / or elements other than the stated components, steps, operations and / or elements. Like reference numerals refer to like elements throughout the specification.

[0040] Spatially relative terms such as "below," "bottom," "lower," "upper," "top," "top," and the like may be used to easily describe the relationship of one element or component to another, as illustrated in the figures. Spatially relative terms should be understood to encompass different orientations of elements in use or operation in addition to the orientation depicted in the figures. For example, if an element depicted in the figures is inverted, an element described as "below" or "below" another element may also be positioned "above" the other element. Thus, the exemplary term "below" may encompass both an orientation of below and above. Elements may be oriented in other directions, and thus the spatially relative terms may be interpreted accordingly.

[0041] As used herein, the "planar direction" can be interpreted as the direction perpendicular to the polarizer and / or transparent conductive layer, ie, the direction viewed from the user's viewing side.

[0042] <Light-control laminate> FIG. 1 is a diagram showing the stack structure of a light-controlling laminate according to one embodiment of the present invention, and FIGS. 2a to 2e are diagrams showing the stack structure of a polarizing plate according to one or more embodiments of the present invention.

[0043] Referring to FIG. 1, a light-controlling stack according to one embodiment of the present invention may include a first polarizer 100-1, a second polarizer 100-2, a first transparent conductive layer 200-1, a second transparent conductive layer 200-2, and a liquid crystal layer 300.

[0044] Referring to FIG. 2, the polarizing plate 100 includes a polarizer 110, and may further include functional layers, such as a protective layer 120, a retardation adjusting layer 130, and a refractive index adjusting layer 140, on one or both sides of the polarizer 110.

[0045] For example, the polarizing plate 100 may include a polarizer 110 and a protective layer 120 stacked on one or both sides of the polarizer 110 (see FIGS. 2a and 2b), or may include a polarizer 110, a protective layer 120 stacked on one side of the polarizer 110, and a retardation adjusting layer 130 stacked on the other side of the polarizer 110 opposite the one side (see FIG. 2c). Alternatively, the polarizing plate 100 may include a polarizer 110, a protective layer 120 stacked on one side of the polarizer, and a retardation adjusting layer 130 and a refractive index adjusting layer 140 stacked in sequence on the other side of the polarizer 110 opposite the one side (see FIG. 2d). Alternatively, the polarizer 110, a protective layer 120 stacked on one side of the polarizer, and a protective layer 120 and a retardation adjusting layer 130 stacked in sequence on the other side of the polarizer 110 opposite the one side (see FIG. 2e).

[0046] In one or more embodiments of the present invention, the polarizer 100, i.e., at least one of the first polarizer 100-1 and the second polarizer 100-2, may have an S calculated by the following equation 1 of 0.5 to 4.0 N·mm, preferably 0.5 to 3.0 N·mm.

[0047]

number

[0048] In the above formula 1, E is the elastic modulus (N / mm 2 ), t is the thickness (mm) and ν is the Poisson's ratio.

[0049] The polarizing plate 100 of the present invention can improve rigidity by satisfying the above formula 1, and may be suitable for application to smart windows.

[0050] That is, if S in the above formula 1 is outside the above range, the polarizing plate 100 may be easily warped or may be too soft and easily bent, and may be lifted or pressed during transportation or bonding, causing bubbles or damage.

[0051] The polarizing plate 100 may have a thickness of 50 to 300 μm, preferably 70 to 200 μm, and more preferably 80 to 170 μm. In this case, the polarizing plate 100 can maintain its optical properties while preventing lift-up when bonded to glass for application to a smart window, thereby preventing the thickness of the smart window from increasing.

[0052] Meanwhile, the polarizing plate 100 has an elastic modulus of 2000 to 8000 N / mm so that S calculated by the above formula 1 satisfies 0.5 to 4.0 N·mm. 2 , preferably 3000 to 6000 N / mm 2 In this case, it is advantageous to prevent the polarizing plate 100 from being lifted or pressed down during transportation or bonding.

[0053] The polarizer and functional layer constituting the polarizing plate 100 are not particularly limited as long as they are made of materials that can satisfy the value of S calculated by the above-mentioned formula 1 of 0.5 to 4.0 N·mm.

[0054] The polarizer 110 may be a conventional or later developed polarizer, such as a stretched polarizer or a coated polarizer.

[0055] In one embodiment, the stretched polarizer may include a stretched polyvinyl alcohol (PVA)-based resin. The polyvinyl alcohol (PVA)-based resin may be a polyvinyl alcohol-based resin obtained by saponifying a polyvinyl acetate-based resin. Examples of polyvinyl acetate-based resins include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate with other monomers copolymerizable therewith. The other monomers may be unsaturated carboxylic acid-based, unsaturated sulfonic acid-based, olefin-based, vinyl ether-based, or acrylamide-based monomers having an ammonium group. The polyvinyl alcohol (PVA)-based resin may also be modified, such as polyvinyl formal or polyvinyl acetal modified with aldehydes.

[0056] In one embodiment, the coating type polarizer may be formed using a liquid crystal coating composition, which may include a reactive liquid crystal compound and a dichroic dye.

[0057] The reactive liquid crystal compound may refer to a compound containing a mesogen skeleton and one or more polymerizable functional groups. Such reactive liquid crystal compounds are known in various ways as reactive mesogens (RMs). The reactive liquid crystal compound can be polymerized by light or heat to form a cured film in which a polymer network is formed while maintaining the liquid crystal alignment.

[0058] The reactive liquid crystal compound may be a monofunctional or polyfunctional reactive liquid crystal compound. The monofunctional reactive liquid crystal compound is a compound having one polymerizable functional group, and the polyfunctional reactive liquid crystal compound is a compound having two or more polymerizable functional groups.

[0059] The dichroic dye is a component contained in the liquid crystal coating composition that imparts polarization properties and has different absorbance in the long axis direction and the short axis direction of the molecule. The dichroic dye may be any conventional or later-developed dichroic dye, for example, one or more 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.

[0060] The liquid crystal coating composition 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, chloroform, etc. The liquid crystal coating composition may further include a labeling agent, a polymerization initiator, etc., within a range that does not impair the polarization properties of the coating film.

[0061] The protective layer 120 serves to protect the polarization characteristics of the polarizer 110 from post-processing and external environments, and may be implemented in the form of a protective film.

[0062] 2a and 2b, the protective layer 120 may be formed on one or both surfaces of the polarizer 110 in direct contact therewith, but is not limited thereto. For example, the protective layer may be used as a multi-layer structure in which one or more protective layers are continuously stacked, or may be formed in direct contact with other functional layers.

[0063] In one or more embodiments, the protective layer 120 may include one or more selected from the group consisting of 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 polymer (COP).

[0064] The retardation adjusting layer 130 complements the optical properties of the optical laminate and may be implemented in the form of a retardation film, or may be a conventional or later-developed retardation film, etc. For example, a quarter-wave plate (1 / 4 wave plate) or a half-wave plate (1 / 2 wave plate) for delaying the phase of light may be used, and these may be used alone or in combination.

[0065] 2c and 2d, the retardation adjusting layer 130 may be formed on one surface of the polarizer 110 in direct contact therewith, but is not limited thereto. For example, as shown in FIG. 2e, the retardation adjusting layer 130 may be formed on one surface of the protective layer 120, and the polarizer 110, the protective layer 120, and the retardation adjusting layer 130 may be sequentially stacked.

[0066] The retardation adjusting layer 130 may be a polymer stretched film obtained by stretching a polymer film that can be given optical anisotropy by stretching in an appropriate manner, or a liquid crystal polymer film.

[0067] In one embodiment, the polymer stretched film may be a polymer layer containing polyolefins such as polyethylene (PE) or polypropylene (PP), cycloolefin polymers (COP) such as polynorbornene, polyesters such as polyvinyl chloride (PVC), polyacrylonitrile (PAN), polysulfone (PSU), acrylic resins, polycarbonate (PC), or polyethylene terephthalate (PET), polyacrylate, cellulose ester polymers such as polyvinyl alcohol (PVA), or triacetyl cellulose (TAC), or a copolymer of two or more monomers among the monomers forming the polymers.

[0068] The method for obtaining the stretched polymer film is not particularly limited, and can be, for example, by molding the polymer material into a film and then stretching it. The film-forming method is not particularly limited, and can be formed into a film by known methods such as injection molding, sheet molding, blow molding, injection blow molding, inflation molding, extrusion molding, foam molding, and cast molding. Secondary processing methods such as compressed air molding and vacuum forming can also be used. Among these, extrusion molding and cast molding are preferred. In this case, for example, an unstretched film can be extruded using an extruder equipped with a T-die, a circular die, or the like. When obtaining a molded product by extrusion molding, a material in which various resin components, additives, etc. have been melt-kneaded in advance can be used, or the product can be formed through melt-kneading during extrusion molding. Alternatively, an unstretched film can be cast-molded by dissolving various resin components in a solvent common to the various resin components, such as chloroform or methylene dichloride, followed by casting, drying, and solidification.

[0069] The polymer stretched film may be produced by uniaxially stretching the formed film in the mechanical direction (MD; machine direction, lengthwise or longitudinal direction) or uniaxially stretching the formed film in the transverse direction (TD; widthwise or transverse direction) of the mechanical direction. Alternatively, a biaxially stretched film may be produced by stretching the formed film using a method such as sequential biaxial stretching with roll stretching and tenter stretching, simultaneous biaxial stretching with tenter stretching, or biaxial stretching with tubular stretching.

[0070] The liquid crystal polymer film may include a reactive liquid crystal compound in a polymerized state. The reactive liquid crystal compound may be the same as the reactive liquid crystal compound of the coating-type polarizer described above.

[0071] In one or more embodiments, the thickness of the retardation adjusting layer 130 may be 10 to 100 μm in the case of a polymer stretched film, and may be 0.1 to 5 μm in the case of a liquid crystal polymer film.

[0072] The refractive index control layer 140 is provided to compensate for a refractive index difference of the optical laminate caused by the transparent conductive layer 200, and may serve to improve visibility by reducing the refractive index difference. The refractive index control layer 140 may also be provided to correct a color caused by the transparent conductive layer 200. Meanwhile, when the transparent conductive layer has a pattern, the refractive index control layer 140 can compensate for a transmittance difference between a patterned region where the pattern is formed and a non-patterned region where the pattern is not formed.

[0073] Specifically, the transparent conductive layer 200 is stacked adjacent to another member (e.g., polarizer 110) having a different refractive index from the transparent conductive layer 200, and the difference in refractive index between the adjacent layers may cause a difference in light transmittance. In particular, when a pattern is formed on the transparent conductive layer, a problem may occur in which the patterned region and the non-patterned region are visually distinguishable. Therefore, by including the refractive index adjusting layer 140, the refractive index is compensated for, thereby reducing the difference in light transmittance of the optical stack. In particular, when a pattern is formed on the transparent conductive layer, the patterned region and the non-patterned region are visually distinguishable.

[0074] In one embodiment, the refractive index of the refractive index adjusting layer 140 may be appropriately selected depending on the material of the adjacent member, and may be preferably 1.4 to 2.6, and more preferably 1.4 to 2.4, in order to prevent light loss due to a sharp difference in refractive index between the other member, such as the polarizer 110, and the transparent conductive layer 200.

[0075] The refractive index adjustment layer 140 is not particularly limited as long as it can prevent a sharp difference in refractive index between other components such as the polarizer 110 and the transparent conductive layer 200. The refractive index adjustment layer 140 may be formed using a compound used to form a conventional or later-developed refractive index adjustment layer, for example, a refractive index adjustment layer-forming composition containing a polymerizable isocyanurate compound.

[0076] In one embodiment, the polarizing plate 100 may further include other components in addition to the above-mentioned components to support or enhance the properties of the polarizer, for example, an overcoat layer to further improve mechanical durability.

[0077] The thickness of each of the functional layers other than the retardation adjusting layer 130 may be 1 to 30 μm, more preferably 2 to 20 μm. The thickness may refer to the thickness after drying, and when each thickness satisfies the above range, the film can be thinned and each functional layer can perform its function without any problems.

[0078] The transparent conductive layer 200 is provided to drive the liquid crystal layer 300 and may be formed in direct contact with the polarizer 100 .

[0079] For example, as shown in FIG. 1, the first transparent conductive layer 200-1 may be formed in direct contact with the first polarizer 100-1, and the second transparent conductive layer 200-2 may be formed in direct contact with the second polarizer 100-2.

[0080] Conventional light-control laminates used in the manufacture of smart windows and the like are manufactured by forming a conductive layer for driving liquid crystals on one side of the laminate and laminating the other side with a polarizer. However, the light-control laminate of the present invention does not include a separate substrate for forming the conductive layer, and instead forms the conductive layer directly on one side of the polarizer, thereby reducing the thickness of the laminate and improving the transmittance and bending characteristics in the light-transmitting mode.

[0081] In one embodiment, the first transparent conductive layer 200-1 and / or the second transparent conductive layer 200-2 formed in direct contact with at least one of the first polarizer 100-1 and the second polarizer 100-2 share a contact surface with the first polarizer 100-1 and / or the second polarizer 100-2 and are formed on the polarizer without a separate substrate. For example, the first transparent conductive layer 200-1 and / or the second transparent conductive layer 200-2 may be formed by depositing on the upper surface of a coating layer formed on the first polarizer 100-1 and / or the second polarizer 100-2. In this case, the first transparent conductive layer 200-1 and / or the second transparent conductive layer 200-2 may be formed in direct contact with the pre-treated surface of the polarizer after pre-treatment such as corona treatment or plasma treatment is performed on one surface of the polarizer to improve adhesion to at least one of the first polarizer 100-1 and the second polarizer 100-2. The pretreatment is not limited to corona treatment or plasma treatment, and any conventional or later developed pretreatment process may be used within the scope of the present invention.

[0082] In another embodiment of the present invention, the first transparent conductive layer 200-1 and / or the second transparent conductive layer 200-2, which are formed in direct contact with at least one of the first polarizer 100-1 and the second polarizer 100-2, may be formed in direct contact with the polarizer via an easy-adhesion layer (not shown) provided on one side of the polarizer to improve adhesion to the polarizer. The easy-adhesion layer may be made of a conventional or later-developed adhesive. In one or more embodiments, an acrylic adhesive, a rubber adhesive, a silicone adhesive, a urethane adhesive, a polyvinyl alcohol adhesive, a polyvinylpyrrolidone adhesive, a polyacrylamide adhesive, a cellulose adhesive, a vinyl alkyl ether adhesive, or the like may be used. The adhesive is not particularly limited as long as it has adhesive strength and point elasticity. However, from the viewpoint of availability, an acrylic adhesive may be used, and may contain, for example, a (meth)acrylate copolymer, a crosslinking agent, and a solvent.

[0083] The transparent conductive layer 200 may be formed by depositing and coating one surface of the polarizer 100 using a method commonly used in the art. For example, the transparent conductive layer 200 may be formed by selecting an appropriate process from coating processes such as spin coating, roller coating, bar coating, dip coating, gravure coating, curtain coating, die coating, spray coating, doctor coating, and kneader coating; printing (coating) processes such as screen printing, spray printing, inkjet printing, relief printing, intaglio printing, and planographic printing; and deposition processes such as CVD (chemical vapor deposition), PVD (physical vapor deposition), and PECVD (plasma enhanced chemical vapor deposition).

[0084] In the light-control laminate of the present invention, at least one of the first transparent conductive layer 200-1 and the second transparent conductive layer 200-2 preferably has a visible light transmittance of 50% or more, and may include, for example, one or more selected from the group consisting of transparent conductive oxides, metals, carbon-based materials, conductive polymers, conductive inks, and nanowires. However, this is not limited thereto, and conventional or later-developed transparent conductive layer materials may also be used.

[0085] In one or more embodiments, the transparent conductive oxide may include one or more selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), fluorine tin oxide (FTO), and zinc oxide (ZnO).

[0086] The metal may include one or more selected from 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 these, and may include, for example, a silver-palladium-copper (APC) alloy or a copper-calcium (CuCa) alloy.

[0087] The carbon-based material may include at least one selected from the group consisting of carbon nanotubes (CNTs) and graphene.

[0088] The conductive polymer may be a conventional or later developed conductive polymer material, for example, polythiophene, poly(3,4-ethylenedioxythiophene), polyaniline, polyacetylene, polydiacetylene, polyphenylene, polyphenylene vinylene, polyphenylene sulfide, polythienylene vinylene, polythiophene vinylene, polyfluorene, polypyrrole, poly(3,4-ethylenedioxythiophene):polystyrene sulfonate, poly(3,4-ethylenedioxythiophene):camphorsulfonic acid, poly(3,4-ethylenedioxythiophene):toluene ... The polythiophene may contain one or more selected from the group consisting of 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, and preferably may be poly(3,4-ethylenedioxythiophene).

[0089] The conductive ink may be an ink containing a metal powder mixed with a curable polymer binder, and the nanowires may be, for example, silver nanowires (AgNWs).

[0090] At least one of the first transparent conductive layer 200-1 and the second transparent conductive layer 200-2 may be formed as a two-layer structure including a metal layer and a transparent conductive oxide layer by combining the above materials, for example, to reduce the reflectance and increase the transmittance of incident light.

[0091] The transparent conductive layer 200 of the present invention may have an alignment layer between it and the liquid crystal layer 300. The alignment layer is preferably photo-aligned to impart alignment to the liquid crystal compound 310. The alignment layer may be fabricated by applying and curing an alignment layer coating composition containing an alignment polymer, a photopolymerization initiator, and a solvent. The alignment polymer is not particularly limited, but may be a polyacrylate resin, a polyamic acid resin, a polyimide resin, a polymer containing a cinnamate group, or any other conventional or later-developed polymer capable of exhibiting alignment.

[0092] The liquid crystal layer 300 included in the light-controlling laminate of the present invention can change the driving mode of the optical laminate to a light-transmitting mode or a light-blocking mode by adjusting the transmittance of light incident from one or more directions by the electric field generated by the transparent conductive layer 200.

[0093] The liquid crystal layer 300 may include a liquid crystal compound 310 and may be located, for example, in the light control region within a space provided by a sealant layer (not shown) and a spacer (not shown) provided between the first transparent conductive layer 200-1 and the second transparent conductive layer 200-2.

[0094] The liquid crystal compound 310 is not particularly limited as long as it is driven by an electric field and can control the light transmittance, and any conventional or later developed liquid crystal compound may be used. For example, the above-mentioned reactive liquid crystal compound of the coating-type polarizer may be similarly applied.

[0095] The sealant may include a curable resin as a base resin. The base resin may be a UV-curable resin or a thermosetting resin known in the art for use in sealants. The UV-curable resin may be a polymer of a UV-curable monomer. The thermosetting resin may be a polymer of a thermosetting monomer.

[0096] The base resin of the sealant may be, for example, an acrylate-based resin, an epoxy-based resin, a urethane-based resin, a phenol-based resin, or a mixture of these resins. In one embodiment, the base resin may be an acrylate-based resin, and the acrylate-based resin may be a polymer of an acrylic monomer. The acrylic monomer may be, for example, a multifunctional acrylate. In another embodiment, the sealant may further include a monomer component in the base resin. The monomer component may be, for example, a monofunctional acrylate. In this specification, a monofunctional acrylate may refer to a compound having one acrylic group, and a multifunctional acrylate may refer to a compound having two or more acrylic groups. The curable resin may be cured by ultraviolet irradiation and / or heating. The ultraviolet irradiation conditions or heating conditions may be appropriately set within a range that does not impair the objectives of the present application. The sealant may further include an initiator, for example, a photoinitiator or a thermal initiator, as needed.

[0097] The sealant may be formed by a method commonly used in the art, for example, by drawing the sealant onto the outer periphery (i.e., non-active area) of the liquid crystal layer using a dispenser equipped with a nozzle.

[0098] The spacers may include at least one of ball spacers and column spacers, and are preferably ball spacers. The number of ball spacers may be one or more, and the diameter thereof is preferably 1 to 10 μm. In addition, when viewed from the planar direction, the area of ​​the ball spacers in the liquid crystal layer 300 is preferably 0.01 to 10% of the area of ​​the liquid crystal layer 300 in terms of improving user visibility and transmittance in the transmission mode.

[0099] The liquid crystal layer 300 included in the light-controlling laminate of the present invention may include a polymer network, as described below, and the polymer network may be formed by a crosslinking reaction of a polymerizable compound. In order to maintain a uniform initial alignment of the liquid crystal compound 310 in the liquid crystal layer when the polymer network is formed, it is preferable to use an alignment film having strong surface anchoring energy. Methods for forming such an alignment film include a rubbing method using a rubbing process and photo-alignment using ultraviolet light, and the photo-alignment method generally has a weaker surface anchoring energy than the rubbing method. More specifically, an alignment film formed by the rubbing method has a surface anchoring energy of about 1×10 -3 J / m 2 The surface anchoring energy of the alignment film formed by the photoalignment method is approximately 1 × 10 -6 J / m 2 Therefore, in order to maintain a uniform initial alignment of the liquid crystal compound 310 when a polymer network is formed in the liquid crystal layer 300, the surface of the second transparent conductive layer 200-2 of the present invention that contacts the liquid crystal layer 300 may be rubbed and aligned by a rubbing method.

[0100] In one embodiment, the transparent conductive layer 200 may have a thickness of 1 μm or less, preferably 10 nm to 500 nm, and more preferably 30 nm to 200 nm, in which case the transparent conductive layer 200 does not significantly change in characteristics due to external stress while ensuring a predetermined transmittance, and a thin light-control stack can be manufactured.

[0101] The liquid crystal layer 300 may include a polymer network and a liquid crystal compound 310, and may be located, for example, in the light control region, in the space provided by the polymer network between the first transparent conductive layer 200-1 and the second transparent conductive layer 200-2.

[0102] As described above, a sealant and spacers are required to maintain a certain space, i.e., a cell gap, within the liquid crystal layer, in which the liquid crystal compound resides. However, including column spacers within the liquid crystal layer to maintain the cell gap complicates the manufacturing process, increasing manufacturing costs. Furthermore, the process of forming spacers by irradiating photoresist with ultraviolet light can damage the alignment layer, resulting in changes in transmittance. Furthermore, using ball spacers to maintain the cell gap within the liquid crystal layer can impair the maintenance of a solid cell gap, making it difficult to maintain a consistent in-plane optical color, and can lead to current shorts in the optical stack. Furthermore, using a sealant to maintain the cell gap within the liquid crystal layer can result in a decrease in apparent quality due to the visibility of the sealant, and can lead to defects such as sealant tearing during handling of the optical stack or thickness differences between the sealant and the spacers included in the sealant.

[0103] The liquid crystal layer 300 can properly maintain the cell gap of the liquid crystal layer without using a separate sealant and / or spacer by including a polymer network together with the liquid crystal compound 310. In addition, since the cell gap is maintained by a single polymer network configuration, rather than a combination of a sealant and a spacer, there is an advantage in that defects due to thickness differences between the sealant and the spacer can be fundamentally prevented.

[0104] The liquid crystal compound 310 is not particularly limited as long as it is driven by an electric field and can control light transmittance, and any conventional or later-developed liquid crystal compound may be used. For example, the above-described reactive liquid crystal compound of the coating-type polarizer may be similarly applied.

[0105] The liquid crystal compound may include a chiral nematic (cholesteric) liquid crystal compound, and the chiral nematic liquid crystal compound may include a nematic liquid crystal compound and a chiral compound.

[0106] Nematic liquid crystal compounds have long, rod-like molecules arranged parallel to one another, with no regularity in the molecular center positions, but with order in the molecular axis direction. Nematic liquid crystal compounds have low viscosity and good fluidity because each molecule can move freely along its long axis, and the orientation of each molecule is almost the same up and down, so polarization is offset and they generally do not exhibit ferroelectricity. The type of nematic liquid crystal compound is not particularly limited, and any compound containing a mesogenic group is acceptable.

[0107] The chiral compounds have symmetrical structures, like the relationship between a right hand and a left hand. Although they have the same chemical structure and physical properties, they are not identical in structure because they are mirror images of each other. When a certain amount of the chiral compound is contained in the nematic liquid crystal compound, it induces a helical period. The type of the chiral compound is not particularly limited as long as it can induce the desired helical period without damaging the liquid crystal properties, e.g., nematic regularity, of the liquid crystal compound.

[0108] The chiral compound for inducing a helical period in the liquid crystal compound 310 must have at least chirality in its molecular structure. Examples of the chiral compound include a compound having one or more asymmetric carbons, a compound having an asymmetric point on a heteroatom such as a chiral amine or chiral sulfoxide, or a compound having an axially asymmetric, optically active site with an axial member such as cumulene or binaphthol.

[0109] The chiral compound may be a low-molecular-weight compound having a molecular weight of not more than 1,500. For example, the chiral compound may be a commercially available chiral nematic liquid crystal, such as chiral dopant liquid crystal S-811 manufactured by Merck or Paliocolor LC756 (manufactured by BASF), but is not limited thereto.

[0110] The chiral nematic liquid crystal compound may contain, but is not limited to, 75 to 99 wt % of the nematic liquid crystal compound and 1 to 25 wt % of the chiral compound based on the total weight of the chiral nematic liquid crystal compound. The helical period, i.e., pitch, of the chiral nematic liquid crystal compound can be controlled by appropriately adjusting the contents of the nematic liquid crystal compound and the chiral compound within the above ranges. The pitch of the chiral nematic liquid crystal compound is not particularly limited, but may be 5 to 20 μm.

[0111] The liquid crystal behavior mode of the liquid crystal layer 300 is not particularly limited, and for example, TN (Twisted nematic) mode, STN (Super twisted nematic) mode, IPS (In-plane switching) mode, FFS (Fringe-field switching) mode, and VA (Vertical alignment) mode can be used, and from the viewpoint of controlling light transmittance, TN (Twisted nematic) mode can be preferably used.

[0112] The liquid crystal layer 300 of the present invention may include a polymer network and a liquid crystal compound 310, and the liquid crystal compound 310 is aligned with a uniform initial alignment. The liquid crystal layer 300 of the present invention differs from conventional polymer-dispersed liquid crystals (PDLCs) in that, while the liquid crystal layer 300 includes a polymer network, the liquid crystal compound 310 does not phase-separate into droplets or capsules but exists in a mixed form with the polymer network and is aligned with a uniform initial alignment within the liquid crystal layer. The liquid crystal layer 300 of the present invention, including the polymer network and the liquid crystal compound 310 aligned with a uniform initial alignment, can implement a light-transmitting mode and a light-blocking mode by adjusting the transmittance of incident light from one or more directions in response to the electric field generated by the transparent conductive layer 200. Therefore, the liquid crystal layer 300 exhibits superior light-blocking efficiency compared to conventional polymer-dispersed liquid crystals, which implement a light-blocking mode by scattering incident light. In addition, the light-controlling laminate of the present invention can realize a light-transmitting mode without applying voltage by appropriately adjusting the transmission axis of the polarizer 100 and the optical axis of the liquid crystal layer 300. Furthermore, compared to conventional polymer-dispersed liquid crystals in which liquid crystals are randomly arranged, the light-controlling laminate requires a lower applied voltage for driving, which is advantageous in that it can reduce power consumption compared to conventional polymer-dispersed liquid crystals.

[0113] The liquid crystal layer 300 may include a cured product of a liquid crystal layer-forming composition including a polymerizable monomer and a liquid crystal compound.

[0114] The polymerizable monomer refers to a compound that forms a polymer network by a photopolymerization reaction or a thermal polymerization reaction, and is not particularly limited. For example, the polymerizable monomer may include an acrylate monomer, and may include at least one selected from the group consisting of isobornyl acrylate, caprolactone acrylate, triethylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, and dipentaerythritol pentaacrylate.

[0115] The polymerizable monomer may include one or more monomers selected from monofunctional to tetrafunctional monomers, preferably trifunctional monomers. The multifunctional monomer has the advantage of being highly compatible with the liquid crystal without giving any impact to the liquid crystal, and can exhibit appropriate phase separation with the liquid crystal.

[0116] The composition for forming a liquid crystal layer may contain 10 to 30 wt % of the polymerizable monomer, preferably 10 to 20 wt %, based on the total weight of the composition. When the composition for forming a liquid crystal layer contains the polymerizable monomer in this content range, the polymer network formed therefrom has a sufficient degree of hardening, which is advantageous in that the cell gap of the liquid crystal layer can be stably maintained and excellent light transmittance and adhesion can be obtained.

[0117] The method for forming the liquid crystal layer 300 using the liquid crystal layer-forming composition is not particularly limited, and for example, the liquid crystal layer 300 can be formed by applying the liquid crystal layer-forming composition onto the second transparent conductive layer 200-2 whose surface is rubbed and then photo-curing or thermal curing the composition.

[0118] When the light control laminate according to the present invention includes a polymer network in the liquid crystal layer 300, it can maintain a stable cell gap without including a sealant or spacer, and may further include one or more of the above-mentioned sealants and spacers as needed within the scope of the present invention without impairing the purpose of the present invention.

[0119] The light-controlling laminate of the present invention may further include other components within the scope of the present invention, for example, a pressure-sensitive adhesive layer, an ultraviolet absorbing layer, a hard coating layer, etc.

[0120] The adhesive layer may be formed using an adhesive or pressure-sensitive adhesive, and preferably has an appropriate adhesive strength so as to prevent peeling, bubbles, etc. from occurring when the optical laminate is handled, as well as transparency and thermal stability.

[0121] The adhesive may be a conventional or later developed adhesive, for example, a light-curable adhesive.

[0122] The photocurable adhesive exhibits strong adhesive strength by crosslinking and curing when exposed to active energy rays such as ultraviolet (UV) and electron beam (EB), and may be composed of reactive oligomers, reactive monomers, photopolymerization initiators, etc.

[0123] The reactive oligomer is an important component that determines the properties of the adhesive and forms a hardened coating by forming a polymer bond through a photopolymerization reaction. Usable reactive oligomers include polyester resins, polyether resins, polyurethane resins, epoxy resins, polyacrylic resins, and silicone resins.

[0124] The reactive monomer functions as a crosslinking agent and a diluent for the reactive oligomer, and influences adhesive properties. Usable reactive monomers include monofunctional monomers, polyfunctional monomers, epoxy-based monomers, vinyl ethers, cyclic ethers, etc.

[0125] The photopolymerization initiator absorbs light energy to generate radicals or cations, thereby initiating photopolymerization, and may be selected to suit the photopolymerizable resin.

[0126] The pressure-sensitive adhesive may be a conventional or later-developed pressure-sensitive adhesive, and in one or more embodiments, may be an acrylic pressure-sensitive adhesive, a rubber pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a polyvinyl alcohol pressure-sensitive adhesive, a polyvinylpyrrolidone pressure-sensitive adhesive, a polyacrylamide pressure-sensitive adhesive, a cellulose pressure-sensitive adhesive, a vinyl alkyl ether pressure-sensitive adhesive, etc. The pressure-sensitive adhesive is not particularly limited as long as it has adhesive strength and viscoelasticity, but from the viewpoint of availability, etc., it may preferably be an acrylic pressure-sensitive adhesive, which may contain, for example, a (meth)acrylate copolymer, a crosslinking agent, and a solvent.

[0127] The crosslinking agent may be a conventional or later developed crosslinking agent, and may include, for example, a polyisocyanate compound, an epoxy resin, a melamine resin, a urea resin, a dialdehyde, a methylol polymer, or the like, and preferably includes a polyisocyanate compound.

[0128] The solvent may include conventional solvents used in the field of resin compositions, such as alcohol-based compounds such as methanol, ethanol, isopropanol, butanol, and propylene glycol methoxyalcohol; ketone-based compounds such as methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, and dipropyl ketone; acetate-based compounds such as methyl acetate, ethyl acetate, butyl acetate, and propylene glycol methoxyacetate; cellosolve-based compounds such as methyl cellosolve, ethyl cellosolve, and propyl cellosolve; and hydrocarbon-based compounds such as hexane, heptane, benzene, toluene, and xylene. These may be used alone or in combination of two or more.

[0129] The thickness of the adhesive layer may be appropriately determined depending on the type of resin acting as the adhesive, adhesive strength, the environment in which the adhesive is used, etc. In one embodiment, the adhesive layer may have a thickness of 0.01 to 50 μm, preferably 0.05 to 20 μm, more preferably 0.1 to 10 μm, in order to ensure sufficient adhesive strength and minimize the thickness of the optical laminate.

[0130] The ultraviolet absorbing layer is not particularly limited as long as it is used to prevent deterioration of the optical laminate due to ultraviolet rays, and examples thereof include salicylic acid-based ultraviolet absorbers (phenyl salicylate, p-tert-butyl salicylate, etc.), benzophenone-based ultraviolet absorbers (2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, etc.), benzotriazole-based ultraviolet absorbers (2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t 2-(2'-hydroxy-3'-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-(3'',4'',5'',6''-tetrahydrophthalimidomethyl)-5'-methylphenyl)benzotriazole, 2,2-methylenebis(4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazo 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-(2-octyloxycarbonylethyl)-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, a mixture of octyl-3-[3-tert-butyl-4-hydroxy-5-(chloro-2H-benzotriazol-2-yl)phenyl]propionate and 2-ethylhexyl-3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate, etc.), cyanoacrylate ultraviolet absorbers (2'-ethylhexyl-2-cyano-3,3-diphenylacrylate, ethyl-2-cyano-3-(3',4'-methylenedioxyphenyl)acrylate, triazine-based UV absorbers, etc. may also be used, and benzotriazole-based UV absorbers or triazine-based UV absorbers, which have high transparency and are excellent in preventing deterioration of polarizing plates and transmittance-variable layers, are preferred, and benzotriazole-based UV absorbers with a more suitable spectral absorption spectrum are particularly preferred. The benzotriazole-based UV absorbers may be bis(bis)-modified, such as 6,6'-methylenebis(2-(2H-benzo[d][1,2,3]triazol-2-yl)-4-(2,4,4-trimethylpentan-2-yl)phenol) or 6,6'-methylenebis(2-(2H-benzo[d][1,2,3]triazol-2-yl)-4-(2-hydroxyethyl)phenol).

[0131] The hard coating layer is not particularly limited as long as it protects components such as a polarizing plate and a transmittance variable layer from external physical and chemical impacts, and any conventional or later developed hard coating layer may be used.

[0132] In one embodiment, the hard coating layer may be formed by applying a composition for forming a hard coating layer to another member and curing the composition with light or heat. The composition for forming a hard coating layer is not particularly limited and may include, for example, a photocurable compound and a photoinitiator.

[0133] The photocurable compound and photoinitiator may be those commonly used in the art without any limitation. For example, the photocurable compound may be a photopolymerizable monomer, a photopolymerizable oligomer, etc., and examples thereof include monofunctional and / or polyfunctional (meth)acrylates. Examples of the photoinitiator include hydroxycyclohexyl phenyl ketone, trimethylbenzoyldiphenylphosphine oxide, acetophenone-based, and oxime ester-based photoinitiators. Commercially available products include Irgacure-184, TPO, and Irgacure-907.

[0134] <Smart windows, automotive and building fixtures> In addition to the light control laminate, the present invention also includes a smart window including the light control laminate. By applying the light control laminate of the present invention to the smart window, handling during processing can be facilitated and breakage and defects can be prevented.

[0135] The present invention also includes a vehicle in which the smart window is applied to at least one of a front window, a rear window, a side window, a sunroof window, and an interior partition, and a building fixture including the smart window. [Example]

[0136] Hereinafter, specific examples of the present invention will be described. However, the present invention is not limited to the examples disclosed below and may be embodied in various different forms. However, these examples are provided to fully disclose the present invention and to fully convey the scope of the invention to those skilled in the art. The present invention is defined only by the claims.

[0137] Manufacturing example 1: Manufacturing a polarizing plate (1) Swelling treatment process A 60 μm thick polyvinyl alcohol film (raw film) (manufactured by Kuraray Co., Ltd., product name "Kuraray Poval Film VF-PE#6000", average polymerization degree 2400, saponification degree 99.9 mol%) was continuously unwound from a raw roll and transported, and immersed in a swelling bath containing pure water at 20°C for 30 seconds. In this swelling treatment process, inter-roll stretching (longitudinal uniaxial stretching) was performed with a difference in peripheral speed between the nip rolls. The stretching ratio based on the raw film was 2.5 times.

[0138] (2) Dyeing process Next, the film passed through the nip rolls was immersed in a dye bath containing pure water / potassium iodide / iodine / boric acid (mass ratio) of 100 / 2 / 0.01 / 0.3 at 30°C for 120 seconds. During this dyeing process, roll-to-roll stretching (longitudinal uniaxial stretching) was performed with a difference in peripheral speed between the nip rolls. The stretching ratio was 1.1 times, based on the film after the swelling treatment step.

[0139] (3) Crosslinking process Next, the film passed through the nip rolls and was immersed for 70 seconds in a first crosslinking bath at 56°C, containing pure water, potassium iodide, and boric acid (mass ratio: 100 / 12 / 4). Roll-to-roll stretching (longitudinal uniaxial stretching) was performed by setting a difference in peripheral speed between the nip rolls and a nip roll prepared between the first and second crosslinking baths. The stretching ratio was 1.9 times, based on the film after the dyeing treatment process.

[0140] (4) Complementary color processing process Next, the film after the crosslinking treatment was immersed for 10 seconds in a second crosslinking bath at 40° C. containing potassium iodide / boric acid / pure water (mass ratio) of 9 / 2.9 / 100.

[0141] (5) Cleaning process Next, the film after the second crosslinking treatment was immersed in a cleaning bath containing pure water at 14°C for 5 seconds, and the shower volume was 5 m 3 Washing was performed at 14°C / h and shower temperature.

[0142] (6) Drying process The washed film was then passed through a drying oven and heated and dried at 80°C for 190 seconds to produce a polarizer film. The moisture content after drying was 13.6%, and the thickness of the resulting polarizer film was approximately 18µm.

[0143] (7) Bonding process Next, a water-based adhesive containing 5 parts by weight of polyvinyl alcohol per 100 parts by weight of water was prepared as the adhesive. Then, protective films (PET) were laminated on both sides of the polarizer film using the prepared UV adhesive. The resulting laminate was exposed to UV light to cure the adhesive, producing a first polarizing plate and a second polarizing plate. The thicknesses of the produced polarizing plates are shown in Table 1.

[0144] Manufacturing Example 2: Fabrication of transparent conductive layer A PEDOT functional conductive layer-forming composition was applied onto the protective layers of the first polarizer and the second polarizer, and dried at 90°C for 5 to 10 minutes to form a functional conductive layer, thereby laminating a first transparent conductive layer and a second transparent conductive layer, respectively.

[0145] The composition for forming the PEDOT functional conductive layer was a mixture of 0.6 wt % PEDOT:PSS, 32.4 wt % ethanol, 40 wt % deionized water, and 27 wt % 2-methoxyethanol.

[0146] Manufacturing example 3: Fabrication of alignment film An alignment liquid was coated on each of the first and second transparent conductive layers prepared in Preparation Example 2, and then dried (80° C. / 2 minutes).

[0147] Thereafter, the dried alignment liquid was irradiated with UV light to form a first alignment film and a second alignment film.

[0148] Manufacturing Example 4: Manufacturing of polymer dispersed liquid crystal molecular layer A mixture of ethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, and 3,5,5-trimethylhexylacrylate was used as the prepolymer, and a single liquid crystal molecule with bicyclohexylbenzene as the central skeleton and cyano group as the functional group was used as the liquid crystal molecule. The prepolymer, liquid crystal molecule, and crosslinker were 25 wt%, 70 wt%, and 5 wt%, respectively, to fabricate a polymer dispersed liquid crystal molecular layer.

[0149] Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-3: Fabrication of light-control laminate A sealant (WORLDROCK No. 7632, manufactured by Kyoritsu Co., Ltd.) was applied to the outer periphery of the first polarizer, first transparent conductive layer, and first alignment film manufactured through Preparation Examples 1 to 3. The second polarizer, second transparent conductive layer, and second alignment film were bonded to the first polarizer, first transparent conductive layer, and first alignment film so that the sealant and liquid crystal molecular layer were sandwiched between them, so that the polymer dispersed liquid crystal molecular layer manufactured in Preparation Example 4 could be formed in the area where the sealant was not applied on the first alignment film. The polymer dispersed liquid crystal molecular layer manufactured in Preparation Example 4 was then injected to fabricate light control laminates of Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-3, respectively.

[0150] Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-3: Fabrication of Smart Windows 6.5g of HCl was added to 100g of PVA (Toyo Chemical Co., Ltd.) aqueous solution, and after stirring, 1.5g of butyraldehyde (ACROS Chemical Co., Ltd.) was added. After the addition, the mixture was stirred at 40°C for 4 hours, and the resulting PVB was filtered using distilled water as a solvent to prepare an adhesive solution.

[0151] The adhesive solution prepared as described above was applied to both sides of the light-control laminates of Examples 1-1 to 1-7 and Comparative Examples 1-1 and 1-3 to form adhesive layers with a thickness of 0.5 mm, and then a glass substrate (Normal Soda Lime Glass, manufactured by JMC Glass Co., Ltd.) with a thickness of 2 mm was bonded to each of the adhesive layers to fabricate smart windows of Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-3, respectively.

[0152] Experimental example: Evaluation of physical properties (1) Elastic modulus of polarizing plate The first polarizing plate and the second polarizing plate prepared in Preparation Example 1 were each cut into a size of 100 mm x 10 mm, and the tensile modulus was measured at a measurement speed of 4 mm / min using an autograph AG-X device manufactured by Shimadzu Corporation. The results are shown in Table 1 below.

[0153] (2) Thickness of the polarizing plate The first polarizing plate and the second polarizing plate prepared in Preparation Example 1 were each cut into a size of 100 mm x 10 mm, and the thickness of each was measured using a thin film thickness measuring instrument LY51 manufactured by Sony Corporation. The results are shown in Table 1 below.

[0154] (3) Poisson's ratio of the polarizing plate (ν: Poisson's ratio) The first polarizing plate and the second polarizing plate prepared in Preparation Example 1 were each cut into a size of 85 mm x 7 mm, and the Poisson's ratio was measured at a measurement speed of 3 mm / min using a local tensile testing device TST350E manufactured by Linkam. The results are shown in Table 1 below.

[0155] The elastic modulus, thickness, and Poisson's ratio of the first and second polarizers measured in (1) to (3) above were calculated using Equation 1, and the results are shown in Table 1 below.

[0156]

number

[0157] In the above formula 1, E is the elastic modulus (N / mm 2 ), t is the thickness (mm) and ν is the Poisson's ratio.

[0158] (4) Evaluation of smart windows The appearance of the smart windows of Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-3 was visually inspected to check for defects such as wrinkles, bubbles, and black spots. The number of defects was counted visually, and the size of each defect was measured using an Olympus MX61 optical microscope. The size of the largest defect was recorded. The result was evaluated according to the following evaluation criteria, and the results are shown in Table 1 below.

[0159] <Defective evaluation criteria> ◎: Number of defects 2 or less / Defect size 0.1 mm or less ○: Number of defective pieces: more than 2, less than 5 / Defect size: more than 0.1 mm, less than 0.3 mm △: Number of defective items: more than 5, less than 10 / Defect size: more than 0.3 mm, less than 0.7 mm ×: Number of defective items exceeds 10 / defect size exceeds 0.7 mm

[0160] [Table 1]

[0161] Based on the experimental results, it was confirmed that in the example where at least one of the first and second polarizers had an S calculated using Equation 1 of 0.5 to 4.0 N·mm, defects such as wrinkles, bubbles, and black spots could be minimized when applied to a smart window. In contrast, in the comparative example where at least one of the first and second polarizers had an S calculated using Equation 1 outside the range of 0.5 to 4.0 N·mm, the number and size of defects significantly increased when applied to a smart window.

Claims

1. a first polarizer; a first transparent conductive layer formed on one surface of the first polarizing plate; a second polarizing plate facing the first polarizing plate; a second transparent conductive layer formed on one surface of the second polarizer and facing the first transparent conductive layer; and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer; At least one of the first polarizing plate and the second polarizing plate has a S calculated by the following Equation 1 of 0.5 to 4.0 N·mm. [Equation 1] (In the above formula 1, E is the elastic modulus (N / mm ２ ), t is the thickness (mm) and v is the Poisson's ratio.

2. The light-controlling laminate of claim 1 , wherein at least one of the first polarizing plate and the second polarizing plate includes one or more functional layers selected from the group consisting of a protective layer, a retardation adjusting layer, and a refractive index adjusting layer.

3. The light-control stack of claim 1 , wherein at least one of the first polarizer and the second polarizer has a thickness of 50 to 300 μm.

4. 2. The light-controlling laminate of claim 1, wherein at least one of the first transparent conductive layer and the second transparent conductive layer is formed in direct contact with either one of the first polarizer and the second polarizer without a separate substrate between them.

5. The light-controlling laminate of claim 1, wherein at least one of the first transparent conductive layer and the second transparent conductive layer includes an easy-adhesion layer between the first polarizing plate and the second polarizing plate and is formed in direct contact with the first polarizing plate and the second polarizing plate.

6. 2. The light control stack of claim 1, wherein at least one of the first transparent conductive layer and the second transparent conductive layer comprises at least one selected from the group consisting of transparent conductive oxides, metals, carbon-based materials, conductive polymers, conductive inks, and nanowires.

7. 2. The light-control stack of claim 1, wherein the liquid crystal behavior mode of the liquid crystal layer is any one selected from the group consisting of a twisted nematic (TN) mode, a super twisted nematic (STN) mode, an in-plane switching (IPS) mode, a fringe-field switching (FFS) mode, and a vertical alignment (VA) mode.

8. A smart window comprising the light control stack of claim 1 .

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