Dimming laminate, smart window including the same, and automotive or building fixture using the same

Abstract

SOLUTION: Provided is a dimming laminate comprising a first transparent conductive layer formed on one side of a first polarizing plate; a second transparent conductive layer formed on one side of a second polarizing plate and facing the first transparent conductive layer; and a liquid crystal layer disposed between the first transparent conductive layer and the second transparent conductive layer. The first and second transparent conductive layers include a conductive polymer, and the liquid crystal layer is the cured product of a composition for liquid crystal layer formation including a polymerizable monomer and a liquid crystal compound, the liquid crystal compound being arranged with a uniform initial orientation.EFFECT: It is possible to provide a dimming laminate the thickness of which relative to conventional dimming laminates is conspicuously reduced, for which manufacturing process is simplified, and a smart window including the same, and an automotive or a building fixture using the same. The laminate is hardly separable thanks to excellent adhesion between the liquid crystal and the conductive layer and can, therefore, be prevented from breaking. Even when a polymer is included in the liquid crystal layer, cell drivability is good even at low voltage when a transmission mode is implemented. Normal white can be implemented when no voltages are applied.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] In addition, the liquid crystal compound constituting the liquid crystal does not have a reactive group, and therefore does not have adhesive strength with the conductive layer. Therefore, a sealant must be provided to bond the liquid crystal and the conductive layer, but if the sealant is not provided or is damaged, the laminate will easily peel off.

[0008] Furthermore, when a polymer such as a polymer dispersed liquid crystal (PDLC) is included in a conventional liquid crystal layer, the liquid crystal compound is phase-separated into droplets or capsules within the polymer, and the phase-separated droplet or capsule-shaped liquid crystal compound is arranged in an irregular direction and does not have a uniform initial orientation. In addition, in order to realize a light-blocking mode, it is necessary to maintain a voltage applied, which has the disadvantage of consuming a lot of power.

[0009] Therefore, it is necessary to develop a light-control laminate that has excellent adhesion between the liquid crystal and the conductive layer regardless of whether a sealant is present or damaged, and that can be driven sufficiently at 10 to 30 V so that power consumption for implementing the light-transmitting mode is not increased even if it contains a polymer. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2018-010035 Summary of the Invention [Problem to be solved by the invention]

[0011] An object of the present invention is to provide a light-control laminate that has excellent adhesion between a liquid crystal and a conductive layer and is difficult to peel off.

[0012] Another object of the present invention is to provide a light-controllable laminate that has good cell drivability even at low voltage when implementing a light-transmitting mode, even when a polymer is included in the liquid crystal layer, and that can implement normal white when no voltage is applied.

[0013] Another object of the present invention is to provide a light-controlling laminate whose manufacturing process is simplified by not requiring a separate substrate for forming a conductive layer and a separate alignment film for initially aligning a liquid crystal compound.

[0014] 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.

[0015] However, the problems to be solved by the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0016] The present invention relates to a light-controlling laminate comprising: a first polarizing plate; a first transparent conductive layer formed on one side of the first polarizing plate; a second polarizing plate facing the first polarizing plate; a second transparent conductive layer formed on one side 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, wherein the first transparent conductive layer and the second transparent conductive layer comprise a conductive polymer, and the liquid crystal layer is a cured product of a liquid crystal layer-forming composition comprising a polymerizable monomer and a liquid crystal compound, wherein the polymerizable monomer comprises one or more selected from the group consisting of a trifunctional aziridine-based monomer, a trifunctional isocyanate-based monomer, and an acrylate-based monomer, and the liquid crystal compound is aligned with a uniform initial orientation.

[0017] The polymerizable monomer may include at least one selected from a trifunctional aziridine monomer and a trifunctional isocyanate monomer, and an acrylate monomer.

[0018] The polymerizable monomer may be contained in an amount of 40% by weight or less based on the weight of the liquid crystal compound.

[0019] 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, ECB (Electrically Controlled Birefringence) mode, and VA (Vertical alignment) mode.

[0020] The liquid crystal behavior mode of the liquid crystal layer may be a TN (Twisted Nematic) mode.

[0021] The first and second transparent conductive layers may have a surface in contact with the liquid crystal layer that is rubbed and aligned.

[0022] The conductive polymer may be 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):toluenesulfonic acid, poly(3,4-ethylenedioxythiophene): The polymerizable composition may include one or more polymers selected from the group consisting of polythiophene:dioxythiophene):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.

[0023] 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 therebetween.

[0024] 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, with an easy-adhesion layer interposed therebetween.

[0025] 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.

[0026] The first and second polarizing plates may have a thickness of 30 to 200 μm.

[0027] 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.

[0028] 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.

[0029] The present invention also relates to building fixtures including the smart window. [Effects of the Invention]

[0030] According to the light-controlling laminate of the present invention, the liquid crystal and the conductive layer have excellent adhesion and are not easily peeled off, so that damage to the laminate can be prevented.

[0031] According to the light-control laminate of the present invention, even if a polymer is included in the liquid crystal layer, the cell drivability is good at 10 to 30 V when implementing the light-transmitting mode, and good normal white can be implemented when no voltage is applied.

[0032] In addition, according to the light-controlling laminate of the present invention, the conductive layer containing a conductive polymer material can serve both as an electrode for driving the liquid crystal layer and as an alignment film, and therefore, since a separate alignment film for initial alignment of the liquid crystal compound is not included, the thickness can be significantly reduced compared to conventional light-controlling laminates.

[0033] Furthermore, with the photochromic laminate of the present invention, it is possible to omit the steps of forming a conductive layer on a substrate and then laminating other components to form a conventional photochromic laminate, thereby simplifying the manufacturing process compared to conventional photochromic laminates.

[0034] In addition, 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, so the thickness can be significantly reduced compared to conventional photochromic laminates.

[0035] 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]

[0036] [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

[0037] The present invention relates to a light-control laminate comprising: a first polarizing plate; a first transparent conductive layer formed on one side of the first polarizing plate; a second polarizing plate facing the first polarizing plate; a second transparent conductive layer formed on one side 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, wherein the first transparent conductive layer and the second transparent conductive layer comprise a conductive polymer, and the liquid crystal layer is a cured product of a liquid crystal layer-forming composition comprising a polymerizable monomer and a liquid crystal compound, wherein the polymerizable monomer comprises one or more of a trifunctional aziridine-based monomer, a trifunctional isocyanate-based monomer, and an acrylate-based monomer, and the liquid crystal compound is aligned with a uniform initial orientation.

[0038] 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 may be used, for example, in smart windows.

[0039] 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.

[0040] 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.

[0041] The light-controlling laminate of the present invention can also be used in smart windows in the various technical fields mentioned above. Because the conductive layer is formed directly on the polarizer, no separate substrate is required for forming the conductive layer, resulting in a thin thickness and advantageous flexibility. Even if the conductive layer contains a polymer material, it can be driven at a low voltage. It can achieve good normal white when no voltage is applied and has excellent adhesion, making it particularly suitable for use in smart windows for vehicles or buildings. In one or more embodiments, a smart window incorporating the light-controlling laminate of the present invention can be used in the front, rear, side, and sunroof windows of automobiles, or as building fixtures. In addition to blocking external light, it can also be used as an interior partition or for privacy purposes, such as for dividing the interior space of an automobile or building.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] <Light-control laminate> FIG. 1 is a diagram showing the layer structure of a light-control laminate according to one embodiment of the present invention, and FIG. 2 is a diagram showing the layer structure of a polarizing plate according to one or more embodiments of the present invention.

[0048] Referring to FIG. 1, a light-controlling laminate 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, and the liquid crystal layer 300 may include a liquid crystal compound 310 and a polymer network 320.

[0049] 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.

[0050] 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), a polarizer 110, a protective layer 120 stacked on one side of the polarizer 110, and a phase difference adjusting layer 130 stacked on the other side of the polarizer 110 opposite the one side (see FIG. 2c), a polarizer 110, a protective layer 120 stacked on one side of the polarizer, and a phase difference 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), or a polarizer 110, a protective layer 120 stacked on one side of the polarizer, and a protective layer 120 and a phase difference adjusting layer 130 stacked in sequence on the other side of the polarizer 110 opposite the one side (see FIG. 2e).

[0051] The polarizer 110 may be a conventional or later developed polarizer, such as a stretched polarizer or a coated polarizer.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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 successively stacked, or may be formed in direct contact with other functional layers.

[0060] 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).

[0061] 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.

[0062] 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 to this. 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.

[0063] 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.

[0064] 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 forming the above polymers.

[0065] 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.

[0066] The polymer stretched film may be produced by uniaxially stretching the formed film in the mechanical direction (MD; mechanical direction, lengthwise or longitudinal direction) or uniaxially stretching in the transverse direction (TD; transverse direction, widthwise or transverse direction) of the mechanical direction. Alternatively, a biaxially stretched film may be produced by stretching the formed film using a sequential biaxial stretching method of roll stretching and tenter stretching, a simultaneous biaxial stretching method using tenter stretching, or a biaxial stretching method using tubular stretching.

[0067] 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.

[0068] In one or more embodiments, the thickness of the retardation adjusting layer 130 may be 10 μm to 100 μm in the case of a polymer stretched film, and 0.1 μm to 5 μm in the case of a liquid crystal polymer film.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] In one or more embodiments of the present invention, the polarizer 100 may have a thickness of 30 to 200 μm, preferably 30 to 170 μm, and more preferably 50 to 150 μm. In this case, the polarizer 100 can maintain its optical properties while preventing it from lifting up when bonded to glass for use in a smart window, thereby preventing the thickness of the smart window from increasing.

[0076] 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 .

[0077] 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.

[0078] 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.

[0079] 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 means that the first transparent conductive layer 200-1 and / or the second transparent conductive layer 200-2 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 an 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 by directly contacting the pre-treated surface of at least one of the first polarizer 100-1 and the second polarizer 100-2 after pre-treating one surface of the polarizer with a corona treatment or a plasma treatment to improve adhesion to the polarizer. The pre-treatment is not limited to a corona treatment or a plasma treatment, and any conventional or later-developed pre-treatment process may be used within the scope of the present invention.

[0080] 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.

[0081] In the light control laminate of the present invention, the first transparent conductive layer 200-1 and the second transparent conductive layer 200-2 may contain a conductive polymer, preferably having a transmittance to irritating light of 50% or more. In this case, even if the transparent conductive layer is deformed by external stress, cracks can be prevented from occurring in the transparent conductive layer, and therefore an excessive increase in surface resistance can be prevented.

[0082] 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.

[0083] In one embodiment, the first transparent conductive layer 200-1 and the second transparent conductive layer 200-2 may have a surface that contacts the liquid crystal layer 300 that is rubbed and aligned. Unlike transparent conductive layers containing metal components, the conductive polymer contained in the transparent conductive layer 200 of the present invention can form grooves on its surface, thereby aligning the liquid crystal molecules in the liquid crystal layer at the desired position and direction. In this case, the transparent conductive layer 200 can function as an electrode for driving the liquid crystal layer and as an alignment film. Since no separate alignment film is required, a thinner light-control stack can be manufactured, and the manufacturing process can be simplified.

[0084] To provide the rubbing-oriented transparent conductive layer 200, a rubbing method using a rubbing process and a photo-alignment method using ultraviolet light can be used. Generally, the photo-alignment method has a weaker surface anchoring energy than the rubbing method. Therefore, it is preferable that the transparent conductive layer 200 of the present invention has a surface that contacts the liquid crystal layer 300 oriented by rubbing using a rubbing method.

[0085] 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 is preferably poly(3,4-ethylenedioxythiophene).

[0086] The transparent conductive layer 200 may be formed by a method commonly used in the art, for example, a coating process such as spin coating, roller coating, bar coating, dip coating, gravure coating, curtain coating, die coating, spray coating, doctor coating, or kneader coating; or a printing process such as screen printing, spray printing, inkjet printing, relief printing, intaglio printing, or planographic printing; or the like.

[0087] If the transparent conductive layer 200 of the present invention is not rubbed, an alignment film may be provided between the layer and the liquid crystal layer 300. The alignment film is preferably photo-aligned because it provides alignment to the liquid crystal compound 310. The alignment film may be fabricated by applying and curing an alignment film coating composition containing an alignment polymer, a photopolymerization initiator, and a solvent. The alignment polymer is not particularly limited, but may include polyacrylate resins, polyamic acid resins, polyimide resins, and polymers containing cinnamate groups. Conventional or later-developed polymers capable of exhibiting alignment may also be used.

[0088] 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 in one or more directions by the electric field generated by the transparent conductive layer 200.

[0089] 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 310, and may be located, for example, in the space between the first transparent conductive layer 200-1 and the second transparent conductive layer 200-2 in the light control region.

[0090] 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 can be formed by applying the liquid crystal layer-forming composition onto a transparent conductive layer whose surface has been rubbed and then photo-curing or thermally curing the composition.

[0091] 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.

[0092] 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.

[0093] 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.

[0094] 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.

[0095] The chiral compound for inducing helical periodicity in the liquid crystal compound must have at least chirality in its molecular structure. Examples of the chiral compound include compounds having one or more asymmetric carbons, compounds having an asymmetric point on a heteroatom such as chiral amines or chiral sulfoxides, and compounds having an axially asymmetric, optically active site such as cumulene or binaphthol.

[0096] The chiral compound may be, for example, a low-molecular-weight compound having a molecular weight of not more than 1,500. For example, the chiral compound may be, but is not limited to, a commercially available chiral nematic liquid crystal, such as chiral dopant liquid crystal S-811 manufactured by Merck or Paliocolor LC756 (manufactured by BASF).

[0097] The chiral nematic liquid crystal compound may contain, but is not limited to, 75 to 99 wt % of a nematic liquid crystal compound and 1 to 25 wt % of a 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.

[0098] 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, ECB (Electrically Controlled Birefringence) mode, and VA (Vertical alignment) mode may be used, and preferably TN (Twisted nematic) mode may be used.

[0099] The polymerizable monomer contained in the composition for forming a liquid crystal layer of the present invention means a compound that forms a polymer network (described later) by photopolymerization or thermal polymerization, and may include one or more selected from the group consisting of a trifunctional aziridine monomer, a trifunctional isocyanate monomer, and an acrylate monomer. By including these, the polymerizable monomer can form a polymer network and ensure adhesion to the transparent conductive layer.

[0100] In particular, trifunctional polymerizable monomers contain multifunctional groups, which allows for the formation of dense three-dimensional polymer networking within the liquid crystal layer, favoring the maintenance of the initially designed cell gap. While the polymer network is random, it can also form a uniform network across the entire surface. Furthermore, the trifunctional isocyanate-based monomers and trifunctional aziridine-based monomers react with and bond to hydroxyl groups distributed in the transparent conductive layer, dramatically improving adhesion. Monofunctional or difunctional aziridine-based monomers or isocyanate-based monomers have insufficient functional groups to form a network within the liquid crystal layer and bond with hydroxyl groups in the transparent conductive layer, resulting in insufficient improvement in adhesion.

[0101] The acrylate-based monomer undergoes a curing reaction earlier by UV curing than the relatively slow thermosetting isocyanate-based and aziridine-based monomers, which helps improve processability and handling when being introduced between multiple processes after the bonding process.

[0102] Among the polymerizable monomers, the polymerizable monomer capable of undergoing a photopolymerization reaction may include an acrylate-based monomer, such as n-butyl acrylate, t-butyl acrylate, sec-butyl acrylate, pentyl acrylate, 2-ethylbutyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl diglycol acrylate, n-octyl acrylate, isooctyl acrylate, isononyl acrylate, lauryl acrylate, tetradecyl acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 2-hydroxyethylene glycol (meth)acrylate and 2-hydroxypropylene glycol (meth)acrylate, (meth)acrylic acid, 2-(meth)acryloyloxyacetic acid, 3-(meth)acryloyloxypropyl acid, 4-(meth)acryloyloxybutyric acid, isobornyl acrylate, caprolactone acrylate, triethylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, and dipentaerythritol pentaacrylate.

[0103] Among the polymerizable monomers, those capable of undergoing a thermal polymerization reaction may include a trifunctional isocyanate-based monomer and a trifunctional aziridine-based monomer.

[0104] The trifunctional monomer has the advantage that it does not give any impact to the liquid crystal and has excellent compatibility with the liquid crystal, so that appropriate phase separation with the liquid crystal can be achieved.

[0105] The trifunctional aziridine monomer may include, for example, one or more selected from the group consisting of pentaerythritol-tris-(β-(N-aziridinyl)propionate, trimethylolpropane-tris(β-N-aziridinyl)propionate, trimethylolpropane tris(2-methyl-1-aziridinepropionate), triethylenemelamine, and tri-1-aziridinylphosphine oxide.

[0106] The trifunctional isocyanate monomer may be, for example, an isocyanate addition polymer, an isocyanurate polymer, or a biuret, and may contain triphenylmethane triisocyanate, methylene bistriisocyanate, or the like. From the viewpoint of compatibility with liquid crystals, a hexamethylene diisocyanate-based trifunctional polymer that exists in a liquid state at room temperature is preferred.

[0107] 1, the liquid crystal layer 300 of the present invention may include a polymer network 320 and a liquid crystal compound 310, and the liquid crystal compound 310 is aligned with a uniform initial alignment. Although the liquid crystal layer 300 of the present invention includes the polymer network 320, the liquid crystal compound 310 may not be phase-separated into droplets or capsules but may exist in a mixed form with the polymer network 320 and be aligned with a uniform initial alignment within the liquid crystal layer. The liquid crystal layer 300 may implement a light-transmitting mode and a light-blocking mode by controlling the transmittance of light incident in one or more directions using an electric field generated by the transparent conductive layer 200. Therefore, the liquid crystal layer 300 may exhibit a superior light-blocking rate compared to conventional polymer-dispersed liquid crystals, which implement a light-blocking mode by scattering incident light. In addition, the light-controllable 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-controllable laminate requires a lower applied voltage for driving, thereby reducing power consumption compared to conventional polymer-dispersed liquid crystals, and has the advantage of being able to be driven sufficiently even at 10 to 30 V when realizing a light-transmitting mode. Furthermore, because the liquid crystals are not randomly arranged, a good normal white can be realized without applying voltage.

[0108] The polymer network 320 may be formed by a crosslinking reaction of the polymerizable monomer. In order to maintain a uniform initial alignment of the liquid crystal compound 310 in the liquid crystal layer during the formation of the polymer network, it is preferable to use an alignment film having strong surface anchoring energy. To this end, as described above, the surface of the transparent conductive layer 200 in contact with the liquid crystal layer 300 may be rubbed or the surface of the alignment film in contact with the liquid crystal layer may be photo-aligned.

[0109] Conventional light-control laminates require the inclusion of a sealant and spacers to maintain a cell gap, i.e., a certain amount of space within the liquid crystal layer where the liquid crystal compound resides. However, including column spacers within the liquid crystal layer to maintain the cell gap increases manufacturing costs due to the complex manufacturing process, and the alignment layer can be damaged during the spacer formation process by irradiating photoresist with UV light, resulting in changes in transmittance. Furthermore, using ball spacers to maintain the cell gap of the liquid crystal layer poses problems such as the inability to maintain a firm cell gap, difficulty in maintaining a consistent in-plane optical color, and the risk of current shorts in the optical laminate. Furthermore, using a sealant to maintain the cell gap of 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 laminate or thickness differences between the sealant and the spacers included in the sealant.

[0110] The liquid crystal layer 300 included in the light control laminate of the present invention includes a polymer network together with the liquid crystal compound 310, thereby properly maintaining the cell gap of the liquid crystal layer without the need for a separate sealant and / or spacer. In addition, since the cell gap is maintained by the polymer network alone, rather than by 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.

[0111] In addition, since the composition for forming a liquid crystal layer of the present invention contains the polymerizable monomer, the degree of hardening of the polymer network is sufficient and the adhesion to the transparent conductive layer is excellent, so that even without the use of a separate sealant, there is no risk of separation between the liquid crystal layer and the conductive layer, thereby preventing damage.

[0112] The polymerizable monomer may be contained in an amount of 40 wt % or less, preferably 10 wt % to 40 wt %, based on the weight of the liquid crystal compound 310. When the polymerizable monomer is contained in this content range, it has excellent compatibility with the liquid crystal, does not reduce the viewing angle when no voltage is applied, and does not significantly affect the alignment of the TN liquid crystal caused by the alignment film, resulting in excellent driving performance even at low voltage. In addition, the polymer network formed from the polymerizable monomer has sufficient hardening and excellent adhesion, allowing the liquid crystal to be driven stably.

[0113] The light control laminate of the present invention can maintain a stable cell gap without including a sealant or spacer by including a polymer network 320 in the liquid crystal layer 300. In addition, if necessary, the light control laminate may further include one or more of a sealant and a spacer within the scope of the present invention without impairing the objectives of the present invention.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] 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 in a 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.

[0118] 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.

[0119] 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 light-control laminate is handled, as well as transparency and thermal stability.

[0120] The adhesive may be a conventional or later developed adhesive, for example, a light-curable adhesive.

[0121] 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.

[0122] 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.

[0123] 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.

[0124] The photopolymerization initiator absorbs light energy to generate radicals or cations, thereby initiating photopolymerization, and may be selected to suit the photopolymerizable resin.

[0125] 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.

[0126] 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.

[0127] 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.

[0128] 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, and more preferably 0.1 to 10 μm, in order to ensure sufficient adhesive strength and minimize the thickness of the optical laminate.

[0129] 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).

[0130] 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.

[0131] 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.

[0132] The photocurable compound and photoinitiator may be those commonly used in the art without any restrictions. 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.

[0133] The method for producing the light-controlling laminate of the present invention is not particularly limited, and the steps of forming a first transparent conductive layer on a first polarizing plate and then performing a rubbing process or an alignment film formation process and forming a liquid crystal layer, and forming a second transparent conductive layer on a second polarizing plate and then performing a rubbing process or forming an alignment film and bonding it to the liquid crystal layer can also be produced by a roll-to-roll process.

[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.

[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 for 1 hour and a shower temperature of 14°C.

[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 PEDOT·PSS (manufacturer: DAEHAMANTECH, model: TEA-150) was coated onto the first and second polarizers to a uniform thickness using a 1-inch wire bar cotter (manufacturer: KIPAE ENT, model: #24) and dried at 80°C for 5 minutes to form first and second transparent conductive layers with thicknesses of approximately 200 nm. The first and second polarizers with the first and second transparent conductive layers were then fixed to the vacuum plate of a rubbing machine to rub them in the same direction as the polarizer absorption axis. Physical alignment was performed using a rubbing cloth (material: rayon) at a speed of 10 mm / s, a depth of 0.3 mm, and a RPM of 1,000 times / min, with two passes.

[0145] Production example 3: Production of composition for forming liquid crystal layer Manufacturing Example 3-1 A liquid crystal layer-forming composition was prepared by mixing 2 g of TN liquid crystal (manufacturer: SILICHEM, model: WH-S811) and 0.5 g of HDI isocyanurate trimer (manufacturer: Vencorex Tolonate, model: HDT-LV2), a trifunctional isocyanate monomer, and stirring for 30 minutes.

[0146] Manufacturing Example 3-2 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-1, except that 0.5 g of a trifunctional aziridine monomer, trimethylolpropane tris(2-methyl-1-aziridinepropionate) (manufacturer: DURY CHEMICAL, HD-100), was used instead of the trifunctional isocyanate monomer.

[0147] Manufacturing Example 3-3 In Preparation Example 3-1, 0.01 g of DBTDL (manufacturer: Sigma-Aldrich) was further added as a catalyst for curing the trifunctional isocyanate-based monomer to prepare a composition for forming a liquid crystal layer.

[0148] Manufacturing Example 3-4 2 g of TN liquid crystal (manufacturer: SILICHEM, model: WH-S811), 0.4 g of HDI isocyanurate trimer (manufacturer: Vencorex Tolonate, model: HDT-LV2), a trifunctional isocyanate monomer, and 0.1 g of PETA (pentaerythritol triacrylate; manufacturer: Miwan Special Chemical, model: Miramer M340), a trifunctional acrylic monomer, were mixed together. 0.008 g of DBTDL (manufacturer: Sigma-Aldrich) was added as a catalyst for curing the trifunctional isocyanate monomer, and 0.001 g of CP-4 (manufacturer: Miwan Special Chemical, grade: Micure CP-4) and 0.001 g of TPO (manufacturer: Miwan Special Chemical, Micure TPO) were added as photoinitiators for UV curing of the trifunctional acrylic monomer. The mixture was stirred for 30 minutes to prepare a liquid crystal layer-forming composition.

[0149] Manufacturing Example 3-5 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-4, except that 0.1 g of a monofunctional acrylic monomer, HEA (2-hydroxyethyl acrylate; Sigma-Aldrich), was used instead of the trifunctional acrylic monomer.

[0150] Manufacturing Example 3-6 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-4, except that 0.4 g of a trifunctional aziridine monomer, trimethylolpropane tris(2-methyl-1-aziridinepropionate) (manufacturer: DURY CHEMICAL, HD-100), was used instead of the trifunctional isocyanate monomer.

[0151] Manufacturing Example 3-7 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-5, except that 0.4 g of a trifunctional aziridine monomer, trimethylolpropane tris(2-methyl-1-aziridinepropionate) (manufacturer: DURY CHEMICAL, HD-100), was used instead of the trifunctional isocyanate monomer.

[0152] Manufacturing Example 3-8 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-4, except that the trifunctional isocyanate monomer and catalyst were not used, and 0.5 g of the monofunctional acrylic monomer HEA (2-hydroxyethyl acrylate; Sigma-Aldrich) was used instead.

[0153] Manufacturing Example 3-9 A liquid crystal layer-forming composition was prepared in the same manner as in Preparation Example 3-4, except that the trifunctional isocyanate-based monomer and catalyst were not used, and 0.5 g of a trifunctional acrylic monomer, PETA (pentaerythritol triacrylate; Manufacturer: Miwan Special Chemical, Model: Miramer M340) was used instead.

[0154] Manufacturing Example 3-10 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-3, except that 0.8 g of the trifunctional isocyanate monomer was used.

[0155] Manufacturing Example 3-11 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-3, except that 0.9 g of the trifunctional isocyanate monomer was used.

[0156] Manufacturing Example 3-12 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-1, except that IPDI (isophorone diisocyanate; Sigma-Aldrich) was used instead of the trifunctional isocyanate monomer.

[0157] Manufacturing Example 3-13 A composition for forming a liquid crystal layer was prepared in the same manner as in Preparation Example 3-1, except that HDI (hexamethylene diisocyanate; Sigma-Aldrich) was used instead of the trifunctional isocyanate monomer.

[0158] Manufacturing Example 3-14 A liquid crystal layer-forming composition was prepared using only TN liquid crystal (manufacturer: SILICHEM, model: WH-S811).

[0159] Examples and Comparative Examples: Fabrication of Light-Controlling Laminate The liquid crystal layer forming composition of Preparation Example 3 was coated onto the first transparent conductive layer on the first polarizer prepared in Preparation Examples 1 and 2 using a 3 / 4 inch wire bar coater (manufacturer: KIPAE ENT, model: #4) to have a cell gap of 5 μm.

[0160] After the coating was completed, the absorption axis of the second polarizer having the second transparent conductive layer formed thereon, as prepared in Preparation Examples 1 and 2, was rotated 90° to the absorption axis of the first polarizer, and the second polarizer was bonded so that the rubbed surface of the second transparent conductive layer was in contact with the liquid crystal layer.

[0161] The bonded cells were treated in an autoclave at 60° C. and 6 bar for 30 minutes to form a light-control laminate with a uniform cell gap of 5 μm.

[0162] Experimental example: Evaluation of physical properties (1) Normal white evaluation The normally white state of the light-control laminates manufactured in the examples and comparative examples was visually observed when no voltage was applied, and evaluated according to the following evaluation criteria. The results are shown in Table 1 below.

[0163] <Evaluation criteria> ○: No spots △: 3 spots or less X: 4 or more spots, bunch (2) Evaluation of cell driveability For the light-control laminates manufactured in the examples and comparative examples, two electrodes of a voltage application device (manufacturer: GWinstek, model: APS-7050E) were connected to the electrode surface of the first polarizer and the electrode surface of the second polarizer, respectively, and a voltage of 20 V was applied. The driving state was evaluated according to the following evaluation criteria, and the results are shown in Table 1 below.

[0164] <Evaluation criteria> ○: Driving possible and no unevenness △: Operation possible and 3 or less spots X: Unable to drive and 4 or more spots (3) Evaluation of adhesion The light-control laminates produced in the examples and comparative examples were cut into pieces of 25*150 mm size using a super cutter, and attached to glass using double-sided tape.

[0165] The 180° peel strength of the first and second polarizing plates of the sample was measured using an autograph (manufacturer: SHIMADZU, model: AG-IS) and is shown in Table 1 below.

[0166] [Table 1]

[0167] -Liquid crystal compound: SILICHEM, Grade: WH-S811 -Trifunctional HDI: HDI isocyanurate trimer (manufactured by Vencorex, Tolonate HDT-LV2) - Trifunctional aziridine: Trimethylolpropane tris(2-methyl-1-aziridinepropionate) (manufacturer: DURY CHEMICAL, HD-100) -HEA: 2-hydroxyethyl acrylate (manufactured by Sigma-Aldrich, reagent) -PETA: Pentaerythritol triacrylate (manufacturer: Mione Special Chemical, Miramer M340) -IPDI: Isophorone diisocyanate (manufactured by Sigma-Aldrich, reagent) -HDI: Hexamethylene diisocyanate (manufactured by Sigma-Aldrich, reagent) -DBTDL: Dibutyltin dilaurate (manufactured by Sigma-Aldrich, reagent) -CP-4: Hydroxycyclohexyl phenyl ketone (manufacturer: Mione Specialty Chemical, Micure CP-4) -TPO: Trimethylbenzoyldiphenylphosphine oxide (manufactured by Mione Specialty Chemical, Micure TPO) From the above experimental results, it can be seen that when the polymerizable monomer in the liquid crystal layer includes one or more selected from the group consisting of a trifunctional aziridine-based monomer, a trifunctional isocyanate-based monomer, and an acrylate-based monomer, the polymerizable monomer does not obstruct the field of view, there are no problems with operation, and the adhesion is very good.

[0168] In contrast, Comparative Examples 1 and 2, which contain a bifunctional monomer as the polymerizable monomer in the liquid crystal layer, show a significant decrease in adhesion as well as a decrease in normal white and cell drivability. In the case of Comparative Example 3, which does not contain the polymerizable monomer of the present invention, there is no room for the formation of a polymer network in the liquid crystal layer, so there is no decrease in normal white, but it can be seen that there is no adhesion at all.

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; the first transparent conductive layer and the second transparent conductive layer contain a conductive polymer; the liquid crystal layer is a cured product of a liquid crystal layer-forming composition containing a polymerizable monomer and a liquid crystal compound, the polymerizable monomer includes at least one selected from the group consisting of a trifunctional aziridine monomer, a trifunctional isocyanate monomer, and an acrylate monomer; A light-controlling stack, wherein the liquid crystal compounds are aligned with a uniform initial orientation.

2. The light-controlling laminate according to claim 1 , wherein the polymerizable monomer comprises at least one selected from the group consisting of a trifunctional aziridine-based monomer and a trifunctional isocyanate-based monomer, and an acrylate-based monomer.

3. The light-control laminate according to claim 1 , wherein the polymerizable monomer is contained in an amount of 40% by weight or less relative to the weight of the liquid crystal compound.

4. 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, an electrically controlled birefringence (ECB) mode, and a vertical alignment (VA) mode.

5. The light control laminate according to claim 1 , wherein the first transparent conductive layer and the second transparent conductive layer have a surface that contacts the liquid crystal layer and is oriented by rubbing.

6. 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.

7. 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 either one of the first polarizing plate and the second polarizing plate and is formed in direct contact with the other.

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

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