Polarizing plate for dimmable laminate, dimmable laminate containing the same, smart window, and automotive or building fixtures using the same

Abstract

The present invention relates to a polarizing plate for a photochromic laminate, comprising a polarizer and a protective film formed on one surface of the polarizer, wherein the protective film has a thickness of 100 μm to 300 μm, and a photochromic laminate containing the same. [Effect] The polarizing plate for the dimmable laminate described above and the dimmable laminate containing the same prevent defects caused by steps between the liquid crystal layer and sealant, and provide a smart window with excellent visibility, as well as automotive or building fixtures to which the same is applied.

Description

Technical Field

[0001] The present invention relates to a polarizing plate for a dimming laminate, a dimming laminate including the same, a smart window, and an automotive or building fixture to which the same is applied.

Background Art

[0002] Generally, an external light blocking coating is often applied to the glass window of a moving means such as a vehicle. However, the glass window of a conventional moving means has a fixed transmittance, and the external light blocking coating also has a fixed transmittance.

[0003] Therefore, the window of such a conventional moving means has a fixed overall transmittance, which may induce an accident. For example, when the overall transmittance is set low, there is no problem during the daytime when the light amount around is sufficient, but in the case of nighttime when the light amount around is not sufficient, there is a problem that it is only difficult for a driver or the like to properly check the periphery of the moving means. Or when the overall transmittance is set high, there is a problem that it may cause glare to a driver or the like during the daytime when the light amount around is sufficient. As a result, a dimming laminate that can change the light transmittance when a voltage is applied has been developed.

[0004] The dimming laminate is driven by driving liquid crystal by applying a voltage to vary the transmittance, and achieves the target transmittance by including a liquid crystal layer whose phase changes by applying an electric field for varying the transmittance, and this is applied to a smart window and used in places where a change in light transmittance is required, such as a moving means or a building fixture.

[0005] Generally, in dimmable laminates, a sealant is applied along the outer surface of the liquid crystal layer to prevent the liquid crystal layer from separating. However, as shown in Figure 4, due to the difference in physical properties between the liquid crystal layer 20 and the sealant 30, the first laminate 10-1, located above the liquid crystal layer 20 and sealant 30 formed on the second laminate 10-2, had a problem where a step d occurred on its outer surface. Therefore, particularly in the glass bonding process for application to smart windows, there was a problem where surface waviness and bubble formation occurred, resulting in visible mottling in the appearance of the smart window. Furthermore, smart windows with a highly permeable protective film applied had a problem where bubbles flowed into the liquid crystal layer and deformation occurred when exposed to high temperature and high humidity environments for extended periods. This caused problems in smart windows because the bubbles flowing into the liquid crystal layer were visible as amorphous black spots.

[0006] Korean Patent No. 10-2154513 discloses a smart window with improved transparency and visibility, but it does not acknowledge the aforementioned problems, nor does it offer any alternative solutions to these problems.

[0007] Therefore, there is a need to develop a dimmable laminate that prevents problems caused by steps in the liquid crystal layer, making the unevenness invisible, and improves heat and humidity resistance so that defects do not occur. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Korean Registered Patent No. 10-2154513 [Overview of the project] [Problems that the invention aims to solve]

[0009] The present invention aims to provide a polarizing plate and a light-adjustable laminate containing the same, which prevent defects caused by steps between the liquid crystal layer and the sealant, thereby preventing concerns about reduced visibility due to mottled patterns.

[0010] The present invention aims to provide a polarizing plate that can prevent deformation due to the application of voltage over a long period of time, and a photochromic laminate containing the same.

[0011] Furthermore, the present invention aims to provide a smart window including the polarizing plate and the light-adjusting laminate, and a building fixture for an automobile or building to which the same is applied.

[0012] However, the problems that this invention aims to solve are not limited to those mentioned above, and other problems not mentioned should be clearly understood by an ordinary person from the following description. [Means for solving the problem]

[0013] The present invention relates to a polarizing plate for a photochromic laminate, comprising a polarizer and a protective film formed on one surface of the polarizer, wherein the protective film has a thickness of 100 μm to 300 μm.

[0014] The polarizing plate may have a thickness of 150 μm to 500 μm.

[0015] The protective film may have an in-plane phase difference of less than 4000 nm for light with a wavelength of 550 nm.

[0016] The protective film may have a multilayer structure in which a number of layers are continuously laminated.

[0017] A phase difference adjustment layer may be further included on the surface on which the protective film is not formed.

[0018] The phase difference adjustment layer may include one or more functional layers selected from the group consisting of a hard coating layer and a refractive index adjustment layer.

[0019] The present invention 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; a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer; and a sealant formed along the outer peripheral surface of the liquid crystal layer. At least one of the first transparent conductive layer and the second transparent conductive layer is formed in direct contact with one of the first polarizing plate and the second polarizing plate. The first polarizing plate and the second polarizing plate each include a first protective film and a second protective film on the surface where the first transparent conductive layer and the second transparent conductive layer are not formed. The first protective film and the second protective film each have a thickness of 100 μm to 300 μm, and relates to a light-adjusting laminate characterized by this.

[0020] The first polarizing plate and the second polarizing plate may each have a thickness of 150 to 500 μm.

[0021] The in-plane retardation of the first protective film and the second protective film with respect to light having a wavelength of 550 nm may be less than 4000 nm.

[0022] The first protective film and the second protective film may have a multilayer structure in which a number of layers are continuously laminated.

[0023] At least one of the first polarizing plate and the second polarizing plate may further include a first retardation adjusting layer or a second retardation adjusting layer on the surface where the first protective film or the second protective film is not formed.

[0024] 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 hard coating layer and a refractive index adjusting layer on the retardation adjusting layer.

[0025] At least one of the first transparent conductive layer and the second transparent conductive layer may be formed in direct contact with either the first polarizing plate or the second polarizing plate, without including a separate substrate between them.

[0026] At least one of the first transparent conductive layer and the second transparent conductive layer may be formed in direct contact with either the first polarizer or the second polarizer, including an easy-adhesion layer.

[0027] At least one of the first transparent conductive layer and the second transparent conductive layer may contain one or more selected from the group consisting of transparent conductive oxides, metals, carbon-based materials, conductive polymers, conductive inks, and nanowires.

[0028] The light-adjusting laminate may further include one or more selected from the group consisting of an alignment film, an adhesive layer, and an ultraviolet absorbing layer.

[0029] Furthermore, the present invention relates to a smart window including the dimmable laminate.

[0030] Furthermore, the present invention relates to an automobile to which the smart window is applied to at least one of the following: a front window, a rear window, a side window, a sunroof window, and an interior partition.

[0031] Furthermore, the present invention relates to building fixtures including the smart window. [Effects of the Invention]

[0032] According to the polarizing plate and dimmable laminate containing the same, defects due to steps between the liquid crystal layer and sealant do not occur, resulting in no mottled patterns and excellent visibility.

[0033] Furthermore, the polarizing plate of the present invention and the photochromic laminate containing the same have excellent heat resistance, moisture resistance, and moisture permeability, and can prevent deformation.

[0034] Furthermore, the polarizing plate and the photochromic laminate containing the same of the present invention have a conductive layer formed directly on one surface of the polarizing plate, and do not require a separate substrate for forming the conductive layer, thus simplifying the manufacturing process.

[0035] Furthermore, the present invention can provide a smart window including the polarizing plate and the light-adjusting laminate, and a building fixture for an automobile or building to which the same is applied. [Brief explanation of the drawing]

[0036] [Figure 1] Figure 1 shows a laminated structure of a polarizing plate according to one embodiment of the present invention. [Figure 2] Figure 2 shows a laminated structure of a polarizing plate according to another embodiment of the present invention. [Figure 3] Figure 3 shows the laminated structure of a dimmable laminate according to one embodiment of the present invention. [Figure 4] Figure 4 schematically shows the form in which a step occurs in a conventional dimmable laminate. [Modes for carrying out the invention]

[0037] [Specific details for carrying out the invention] The present invention relates to a polarizing plate that can be laminated on the outermost surface of a photochromic laminate, and more particularly to a polarizing plate for a photochromic laminate that can suppress the occurrence of steps caused by sealant when applied to a photochromic laminate. Specifically, the polarizing plate of the present invention is a polarizing plate for a photochromic laminate that includes a polarizer and a protective film formed on one surface of the polarizer, wherein the protective film has a thickness of 100 μm to 300 μm.

[0038] Furthermore, the present invention relates to a photochromic laminate including the polarizing plates, wherein the photochromic laminate includes a first polarizing plate and a second polarizing plate, each having a first transparent conductive layer and a second transparent conductive layer formed on one surface, and a liquid crystal layer and a sealant provided between the two transparent conductive layers, and the first polarizing plate and the second polarizing plate each include a first protective film and a second protective film, respectively, which are thickened on the surfaces where the transparent conductive layer is not formed.

[0039] More specifically, the dimmable laminate of the present invention 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; a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer; and a sealant formed along the outer peripheral surface of the liquid crystal layer, wherein at least one of the first transparent conductive layer and the second transparent conductive layer is formed in direct contact with either the first polarizing plate or the second polarizing plate, and the first polarizing plate and the second polarizing plate each include a first protective film and a second protective film on the surfaces where the first transparent conductive layer and the second transparent conductive layer are not formed, and the first protective film and the second protective film each have a thickness of 100 μm to 300 μm.

[0040] The dimmable laminate of the present invention is particularly suitable for technical fields in which the transmittance of light can be changed by applying a voltage, and may be used, for example, in smart windows.

[0041] A smart window refers to an optical structure that controls the amount of light or heat passing through by changing its light transmittance through the application of an electrical signal. In other words, a smart window is designed to change between transparent, opaque, and semi-transparent states depending on the voltage applied, and is also called variable transmittance glass, dimmable glass, or smart glass.

[0042] Smart windows can be used as partitions or privacy dividers for the interior spaces of vehicles and buildings, or as skylights in building openings, or as highway signs, billboards, timetables, clocks, or advertising screens, and can replace glass in windows or sunroofs of vehicles such as cars, buses, aircraft, ships, or trains.

[0043] The dimmable laminate of the present invention can also be used in smart windows in the various technical fields mentioned above. However, because the conductive layer is formed directly on the polarizing plate, it does not require a separate substrate for forming the conductive layer. As a result, it is thin, has advantageous bending properties, and is particularly suitable for use in smart windows for vehicles or buildings. In one or more embodiments, a smart window to which the dimmable laminate of the present invention is applied can be used in means of transportation, such as front windows, rear windows, side windows and sunroof windows of automobiles, or building fixtures. In addition to applications of blocking external light, it can also be used for partitioning internal spaces in automobiles or buildings, or for privacy protection, such as internal partitions.

[0044] The embodiments of the present invention will be described in more detail below with reference to the drawings. However, the following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the content of the invention described above, serve to help to better understand the technical concept of the present invention. Therefore, the present invention should not be interpreted as being limited only to the matters described in these drawings.

[0045] The terms used herein are for illustrative purposes only and are not intended to limit the invention. In this specification, the singular form includes the plural form unless otherwise specified in the text. For example, as used herein, “polarizing plate” may mean at least one of the first polarizing plate and the second polarizing plate, and “transparent conductive layer” may mean at least one of the first transparent conductive layer and the second transparent conductive layer.

[0046] As used herein, “comprises” and / or “comprising” are used in a manner that does not exclude the presence or addition of one or more other components, steps, operations, and / or elements other than those mentioned. Throughout the specification, identical reference numerals refer to the same component.

[0047] Spatially relative terms such as "down," "bottom," "lower part," "up," "upper part," and "upper part" can be used to easily describe the correlation between one element or component and another element or component, as shown in the drawing. Spatially relative terms should be understood as terms that include the different orientations of elements in use or operation, in addition to the orientation shown in the drawing. For example, when overturning elements shown in the drawing, an element described as "down" or "lower part" of another element may also be placed "up" of the other element. Therefore, the exemplary term "down" can include both the down and up directions. Elements can also be oriented in other directions, and thus spatially relative terms can be interpreted according to their orientation.

[0048] As used herein, “planar direction” can be interpreted as the direction perpendicular to the polarizer and / or transparent conductive layer, i.e., the direction viewed from the user’s viewing side.

[0049] <Polarizing plate> Figure 1 shows a laminated structure of a polarizing plate according to one embodiment of the present invention, and Figure 2 shows a laminated structure of a polarizing plate according to another embodiment of the present invention.

[0050] Referring to Figure 1, a polarizing plate 100 according to one embodiment of the present invention may include a polarizer 110 and a protective film 120 formed on one surface of the polarizer.

[0051] The polarizing plate 100 may have a thickness of 150 μm to 500 μm, preferably 170 μm to 500 μm, and more preferably 190 μm to 450 μm. In this case, it is possible to prevent the generation or lifting of bubbles due to the step difference between the liquid crystal layer 300 and the sealant 400 that occurs in the glass bonding process, while maintaining the optical properties of the polarizing plate 100.

[0052] The polarizer 110 may be a conventional or subsequently developed polarizer, such as a stretched polarizer or a coated polarizer.

[0053] In one embodiment, the stretched polarizer may contain a stretched polyvinyl alcohol (PVA) resin. The polyvinyl alcohol (PVA) resin may be a polyvinyl alcohol resin obtained by saponifying a polyvinyl acetate resin. Examples of polyvinyl acetate resins include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. The other monomers may be unsaturated carboxylic acid monomers, unsaturated sulfonic acid monomers, olefin monomers, vinyl ether monomers, or acrylamide monomers having an ammonium group. Furthermore, the polyvinyl alcohol (PVA) resin may be a modified form, for example, polyvinyl formal or polyvinyl acetal modified with aldehydes.

[0054] In one embodiment, the coated polarizer may be formed from a liquid crystal coating composition. In this case, the liquid crystal coating composition may include a reactive liquid crystal compound and a dichroic dye, etc.

[0055] The reactive liquid crystal compound can refer to a compound that includes, for example, a mesogen skeleton and further includes one or more polymerizable functional groups. Such reactive liquid crystal compounds are widely known under the name RM (Reactive Mesogen). 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 arrangement.

[0056] 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 may mean a compound containing two or more polymerizable functional groups.

[0057] The aforementioned dichroic dye is a component included in a liquid crystal coating composition that imparts polarization properties and has the property that its absorbance in the long axis direction and absorbance in the short axis direction are different. The aforementioned dichroic dye may be a conventional or subsequently developed dichroic dye, and may include 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.

[0058] The liquid crystal coating composition may further contain a solvent capable of dissolving the reactive liquid crystal compound and the dichroic dye, such as propylene glycol monomethyl ether acetate (PGMEA), methyl ethyl ketone (MEK), xylene, and chloroform. The liquid crystal coating composition may also further contain labeling agents, polymerization initiators, etc., to the extent that they do not impair the polarization properties of the coating film.

[0059] The protective film 120 is intended to prevent surface waviness while preserving the polarization characteristics of the polarizer 110 from subsequent processes and the external environment, and may have a thickness of 100 μm to 300 μm, preferably 125 μm to 300 μm. This is more preferable in terms of mitigating the height difference between the liquid crystal layer and the sealant when applied to a dimmable laminate.

[0060] By satisfying the aforementioned thickness range, the protective film 120, when applied to the dimmable laminate, prevents the visibility of unevenness caused by steps between the liquid crystal layer and sealant that occur during the glass bonding process, improves moisture permeability and heat and humidity resistance, and maintains optical properties.

[0061] Furthermore, the protective film 120 may have an in-plane phase difference Re for light with a wavelength of 550 nm, calculated by the following formula 1, that is less than 4000 nm.

[0062] [Formula 1] Re=(nx-ny)×d In the above mathematical formula 1, nx and ny are the refractive indices of the protective film in the x and y directions for light at a wavelength of 550 nm, respectively, and d is the thickness of the protective film.

[0063] By satisfying the in-plane phase difference Re range, the protective film 120 can have good moisture permeability and heat and moisture resistance without deterioration of optical properties, even in a thickness range of 100 μm to 300 μm.

[0064] The protective film 120 is arranged on one surface of the polarizer 110 and, when applied to the dimmable laminate, is positioned in the outermost direction. Preferably, it is formed on the surface of the polarizer 110 where the transparent conductive layer 200 is not laminated. This effectively suppresses the generation of air bubbles in the sealant step during the glass bonding process, and solves the safety problem of air bubbles flowing into the liquid crystal layer of the dimmable laminate due to moisture permeability.

[0065] In particular, the protective film 120 included in the polarizing plate 100 of the present invention is characterized by being formed as a thick film. However, if such a thick protective film is arranged in the inward direction, which is the direction of the liquid crystal layer, in the dimmable laminate, there may be a problem in which the color characteristics change depending on the viewing angle when the dimmable laminate is driven in the light-shielding mode.

[0066] The protective film 120 may be formed in direct contact with one surface of the polarizer 110, but is not limited to this, and may also be formed, for example, through an adhesive layer described later.

[0067] The protective film 120 may have a single-layer structure, a multi-layer structure in which multiple layers are continuously laminated, or it may be formed in direct contact with other functional layers.

[0068] In one or more embodiments, the protective layer 120 may contain 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). Naphthalate (PEN), polyethylene naphthalate (PE), polyvinyl chloride, and cyclic olefin polymer (COP) are more preferred in terms of improving moisture permeability and heat and moisture resistance.

[0069] On the other hand, as shown in Figure 2, the polarizing plate 100 may further include a phase difference adjustment layer 130 and a hard coating layer 140 on the side of the polarizer 110 where the protective film 120 is not formed.

[0070] The phase difference adjustment layer 130, when applied to the light-adjusting laminate, is for complementing the optical properties and can be realized in the form of a phase difference film or the like. Conventional or subsequently developed phase difference films can be used. For example, a quarter-wave plate (1 / 4 wave plate) or 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.

[0071] The phase difference adjustment layer 130 may be formed in direct contact with the other surface of the polarizer 110 where the protective film 120 is not formed.

[0072] The phase difference adjustment layer 130 may be a polymer stretched film or a liquid crystal polymerized film obtained by stretching a polymer film that can be given optical anisotropy by stretching in an appropriate manner.

[0073] 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, polyvinyl chloride (PVC), polyacrylonitrile (PAN), polysulfone (PSU), acrylic resin, polycarbonate (PC), polyesters such as polyethylene terephthalate (PET), polyacrylate, polyvinyl alcohol (PVA), or cellulose ester polymers such as triacetylcellulose (TAC), or copolymers of two or more monomers that form the polymer.

[0074] The method for obtaining the polymer stretched film is not particularly limited, and for example, it can be obtained by forming the polymer material into a film and then stretching it. The method for forming the film is not particularly limited, and it is possible to form the film using known methods such as injection molding, sheet molding, blow molding, injection blow molding, inflation molding, extrusion molding, foam molding, and cast molding, and secondary processing molding methods such as pressure molding and vacuum molding may also be used. Among these, extrusion molding and cast molding are preferably used. In this case, for example, an unstretched film can be extruded using an extruder equipped with a T-die, a circular die, etc. When obtaining a molded product by extrusion molding, a material in which various resin components and additives have been melt-kneaded in advance can be used, or it can be molded after melt-kneading during extrusion molding. Alternatively, the unstretched film may be cast molded by dissolving various resin components using a solvent common to various resin components, for example, a solvent such as chloroform or methylene chloride, and then casting and drying solidify it.

[0075] The polymer stretched film may be produced by uniaxially stretching the molded film in the mechanical flow direction (MD; Mechanical Direction, longitudinal or longitudinal direction), uniaxially stretching it in a direction perpendicular to the mechanical flow direction (TD; Transverse Direction, transverse or width direction), or by stretching it using methods such as sequential biaxial stretching with roll stretching and tenter stretching, simultaneous biaxial stretching with tenter stretching, or biaxial stretching with tubular stretching to produce a biaxially stretched film.

[0076] The aforementioned liquid crystal polymerization film may contain a reactive liquid crystal compound in a polymerized state. The reactive liquid crystal compound can be treated in the same manner as described above for the reactive liquid crystal compound of the coating-type polarizer.

[0077] In one or more embodiments, the thickness of the phase difference adjustment layer 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 polymerization film.

[0078] The hard coating layer 140 is not particularly limited as long as it protects components such as polarizers and variable transmittance layers from external physical and chemical impacts, and conventional or subsequently developed hard coating layers can be used. Specifically, when applied to crystalline polymer substrates, engineering plastic substrates, and polymer substrates whose surfaces have become new aqueous due to hydrolysis or saponification, where it is difficult to impart adhesion after coating, the adhesion can be increased without a decrease in mechanical properties. Furthermore, if the polymer substrate is subjected to plasma or corona treatment before coating with the hard coating layer of the present invention, the adhesion can be increased even further.

[0079] In this invention, a hard coating layer that can improve surface hardness can be used, taking into consideration the fact that cracks generated during the manufacturing process can be minimized.

[0080] The thickness of the hard coating layer 140 may be 3 μm to 200 μm, specifically 5 μm to 100 μm, and more specifically 7 μm to 30 μm, but is not limited thereto. However, when the thickness of the hard coating layer 140 satisfies the above range, it is possible to manufacture a hard coating layer that has excellent hardness, can be made thin, and hardly exhibits curling. The thickness of the coating layer may refer to the thickness after drying.

[0081] The hard coating layer 140 can be formed by known methods such as die coating, air knife, reverse roll, spray, blade, casting, gravure, microgravure, and spin coating.

[0082] Furthermore, the hard coating layer 140 can be formed by applying a hard coating layer-forming composition to another component and then curing it with light or heat. The hard coating layer-forming composition is not particularly limited and may include, for example, a photocurable compound and a photoinitiator.

[0083] The photocurable compound and photoinitiator can be used without limitation as they are commonly used in the art. For example, the photocurable compound may be a photopolymerizable monomer, a photopolymerizable oligomer, etc., and examples include monofunctional and / or polyfunctional (meth)acrylates. Examples of photoinitiators include hydroxycyclohexyl phenyl ketone, trimethylbenzoyl diphenylphosphine oxide, acetophenone-based, oxime ester-based, etc. Commercial products include Irgacure-184, TPO, and Irgacure-907.

[0084] The polarizing plate 100 of the present invention includes a protective film 120 on one side of the polarizer 110 as described above, and may further include a phase difference adjustment layer 130 and a hard coating layer 140 sequentially on the other side of the polarizer 110, and may also include functional layers such as a refractive index adjustment layer.

[0085] The refractive index adjusting layer, when applied to a photochromic laminate, is provided to compensate for the refractive index difference of the photochromic laminate caused by the transparent conductive layer, and may also serve to improve visibility characteristics by reducing the refractive index difference. Furthermore, the refractive index adjusting layer may also be provided to correct the hue caused by the transparent conductive layer. On the other hand, if the transparent conductive layer has a pattern, the refractive index adjusting layer can compensate for the transmittance difference between the patterned region where the pattern is formed and the unpatterned region where the pattern is not formed.

[0086] Specifically, when a transparent conductive layer is laminated adjacent to other components with different refractive indices (e.g., polarizers), a difference in light transmittance may be induced due to the difference in refractive indices with adjacent layers. In particular, if a pattern is formed on the transparent conductive layer, a problem may arise where the patterned area and the non-patterned area are visually distinguishable. Therefore, by including the refractive index adjustment layer, the difference in light transmittance of the photochromic laminate can be reduced by compensating for the refractive index, and in particular, if a pattern is formed on the transparent conductive layer, the patterned area and the non-patterned area are distinguished and not visually distinguishable.

[0087] In one embodiment, the refractive index of the refractive index adjustment layer may be appropriately selected based on the material of the adjacent other components, but is preferably 1.4 to 2.6, and more preferably 1.4 to 2.4. In this case, it is possible to prevent light loss due to a sudden difference in refractive index between the other components, such as the polarizer, and the transparent conductive layer.

[0088] The refractive index adjusting layer is not particularly limited as long as it can prevent a rapid difference in refractive index between other components such as polarizers and the transparent conductive layer. It can be a compound used in the formation of conventional or subsequently developed refractive index adjusting layers, and may be formed from a refractive index adjusting layer forming composition containing a polymerizable isocyanurate compound, for example.

[0089] In one embodiment, the polarizing plate 100 may further include other functional layers to assist or enhance the polarizer's properties, in addition to the functional layer described above. For example, it may further include an overcoat layer to further improve mechanical durability.

[0090] The thickness of the refractive index adjusting layer and the functional layer that may be further included may be 1 to 30 μm, and more preferably 2 to 20 μm. The thickness may refer to the thickness after drying, and as long as each thickness satisfies the above range, thinning is possible and each functional layer can perform its function without any problems.

[0091] <Dimmable Laminate> Figure 3 shows the laminated structure of a dimmable laminate according to one embodiment of the present invention.

[0092] Referring to Figure 3, the dimmable laminate according to one embodiment of the present invention may include a first polarizing plate 100-1, a second polarizing plate 100-2, a first transparent conductive layer 200-1, a second transparent conductive layer 200-2, a liquid crystal layer 300, and a sealant 400.

[0093] polarizing plate The polarizing plate 100 of the present invention may refer to a first polarizing plate 100-1 and a second polarizing plate 100-2, or either one of them, and the types and characteristics of each layer constituting the polarizing plate can be commonly applied as described in the <Polarizing Plate> section above.

[0094] The first polarizing plate 100-1 and the second polarizing plate 100-2 may each include a first protective film 120-1 and a second protective film 120-2 on one surface of the first polarizer 110-1 and the second polarizer 110-2, respectively, for preventing surface waviness while preserving the polarization characteristics of the first polarizer 110-1 and the second polarizer 110-2 from subsequent processes and the external environment. The first protective film 120-1 and the second protective film 120-2 may have a thickness of 100 μm to 300 μm, preferably 125 to 300 μm. This is more preferable in terms of mitigating the height difference between the liquid crystal layer and the sealant.

[0095] On the other hand, the second protective film 120-2 may be thinner than or the same thickness as the first protective film 120-1, depending on the intended use and application field of the glass bonded product.

[0096] By satisfying the thickness range of the first protective film 120-1 and the second protective film 120-2, it is possible to prevent the visibility of unevenness caused by steps between the liquid crystal layer 300 and the sealant 400 of the polarizing plate 100 that occur during the glass bonding process, improve moisture permeability and heat and humidity resistance, and maintain optical properties.

[0097] Furthermore, the first protective film 120-1 and the second protective film 120-2 may have an in-plane phase difference Re for light with a wavelength of 550 nm, calculated by the following formula 1, that is less than 4000 nm.

[0098] [Formula 1] Re=(nx-ny)×d In the above mathematical formula 1, nx and ny are the refractive indices of the first protective film and the second protective film in the x and y directions for light at a wavelength of 550 nm, respectively, and d is the thickness of the first protective film and the second protective film.

[0099] The first protective film 120-1 and the second protective film 120-2 can have good moisture permeability and heat and moisture resistance without deterioration of optical properties even in a thickness range of 100 μm to 300 μm, by satisfying the in-plane phase difference Re range.

[0100] The first protective film 120-1 and the second protective film 120-2 are arranged in the outermost direction of the dimmable laminate, and it is preferable that they are formed on the surfaces of the first polarizer 110-1 and the second polarizer 110-2 where the transparent conductive layers 200-1 and 200-2 are not formed. This effectively suppresses the generation of air bubbles in the sealant step portion during the glass bonding process and solves the problem of air bubbles flowing into the liquid crystal layer of the dimmable laminate due to moisture permeability. In particular, if the first protective film 120-1 and the second protective film 120-2 of the present invention, which are formed as thick films, are arranged in the inward direction of the dimmable laminate, centered on the polarizers 110-1 and 110-2, there may be a problem in which the color characteristics change depending on the viewing angle when the dimmable laminate is driven in the light-shielding mode.

[0101] The first protective film 120-1 and the second protective film 120-2 may be formed in direct contact with one surface of the respective polarizers 110-1 and 110-2, but are not limited to this, and may also be formed, for example, through an adhesive layer described later.

[0102] The first protective film 120-1 and the second protective film 120-2 may be single-layer structures, multi-layer structures in which multiple layers are continuously laminated, or they may be formed in direct contact with other functional layers.

[0103] On the other hand, as shown in Figure 3, the first polarizer 100-1 and the second polarizer 100-2 may further include, in order, a first phase difference adjustment layer 130-1 and a second phase difference adjustment layer 130-2, and a first hard coating layer 140-1 and a second hard coating layer 140-2 on the surfaces of the polarizers 110-1 and 110-2 where the first protective film 120-1 and the second protective film 120-2 are not formed.

[0104] The first phase difference adjustment layer 130-1, the second phase difference adjustment layer 130-2, the first hard coating layer 140-1, and the second hard coating layer 140-2 can be similarly to the descriptions of the phase difference adjustment layer 130 and the hard coating layer 140 described in the <Polarizing Plate> section, and the descriptions of other functional layers that may be included can also be similarly applied.

[0105] Transparent conductive layer The transparent conductive layers 200-1 and 200-2 are provided for driving the liquid crystal layer 300 and may be formed in direct contact with the polarizing plates 100-1 and 100-2.

[0106] For example, as shown in Figure 3, the first transparent conductive layer 200-1 may be formed in direct contact with the first polarizing plate 100-1, and the second transparent conductive layer 200-2 may be formed in direct contact with the second polarizing plate 100-2.

[0107] Conventional dimmable laminates used in the manufacture of smart windows and the like are manufactured by forming a conductive layer for driving liquid crystals on one surface and laminating the other surface with a polarizing plate. However, the dimmable laminate according to the present invention is characterized by reducing the thickness of the laminate while improving the transmittance and bending characteristics in light-transmitting mode by partially omitting a separate substrate for forming the conductive layer and directly forming the conductive layer on one surface of the polarizing plate.

[0108] In this case, the polarizing plates 100-1 and 100-2 included in the dimmable laminate of the present invention include a protective film with a thickness of 100 μm or more, and have the characteristic of less sagging of the raw material and less surface waviness, especially when applied to a dimmable laminate. Since it is easy to maintain the tension of the raw material between rolls, it is possible to produce a transparent conductive layer with little deviation in in-plane thickness in roll-to-roll continuous production, which is advantageous for achieving rapid in-plane switching and response speed when driving a smart window.

[0109] In one embodiment, 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 polarizing plates, the first polarizing plate 100-1 and the second polarizing plate 100-2, share a contact surface with the first polarizing plate 100-1 and / or the second polarizing plate 100-2, do not include a separate substrate, and are formed on the polarizing plate. For example, the first transparent conductive layer 200-1 and / or the second transparent conductive layer 200-2 may be formed by vapor deposition on the upper surface of a coating layer formed on the first polarizing plate 100-1 and / or the second polarizing plate 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 surface of the polarizing plate with the pre-treated surface after performing a pre-treatment such as corona treatment or plasma treatment on one surface of the polarizing plate in order to improve adhesion to at least one of the polarizing plates, namely the first polarizing plate 100-1 and the second polarizing plate 100-2. The pre-treatment is not limited to corona treatment or plasma treatment, and conventional or subsequently developed pre-treatment processes can be used as long as they do not impair the objectives of the present invention.

[0110] In other embodiments 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 polarizing plate 100-1 and the second polarizing plate 100-2, may be formed in direct contact with the polarizing plate with an easy-adhesion layer (not shown) provided on one surface of the polarizing plate in between, in order to improve adhesion to the polarizing plate. The easy-adhesion layer can use conventional or subsequently developed adhesives, and in one or more embodiments, acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, polyvinyl alcohol adhesives, polyvinylpyrrolidone adhesives, polyacrylamide adhesives, cellulose adhesives, vinyl alkyl ether adhesives, etc., may be used. The adhesive is not particularly limited as long as it has adhesive strength and viscoelasticity, but from the viewpoint of availability, it is preferably an acrylic adhesive, and may contain, for example, a (meth)acrylate copolymer, a crosslinking agent and a solvent.

[0111] The transparent conductive layers 200-1 and 200-2 may be formed by deposition and coating on one surface of the polarizing plates 100-1 and 100-2 by methods commonly used in the art. For example, 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 planar printing; and deposition processes such as CVD (chemical vapor deposition), PVD (physical vapor deposition), and PECVD (plasma-enhanced chemical vapor deposition), as well as dry or wet plating processes, may be selected from among these methods to form the layers.

[0112] In the dimmable 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 transmittance of 50% or more to visible light, and may contain, but is not limited to, one or more selected from the group consisting of transparent conductive oxides, metals, carbon-based materials, conductive polymers, conductive inks and nanowires, and conventional or subsequently developed transparent conductive layer materials may be used.

[0113] 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).

[0114] Furthermore, the aforementioned 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. For example, it may include a silver-palladium-copper (APC) alloy or a copper-calcium (CuCa) alloy.

[0115] The carbon-based material may include one or more materials selected from the group consisting of carbon nanotubes (CNTs) and graphene.

[0116] The conductive polymer can be a conventional or subsequently developed conductive polymer material, such as polythiophene, poly(3,4-ethylenedioxythiophene), polyaniline, polyacetylene, polydiacetylene, polyphenylene, polyphenylene vinylene, polyphenylene sulfide, polythiophenylene vinylene, polyfluorene, polypyrrole, poly(3,4-ethylenedioxythiophene):polystyrene sulfonate, poly(3,4-ethylenedioxythiophene):camphor sulfonic acid, poly(3,4-ethylenedioxythiophene):toluene sulfonic acid, poly(3,4-ethylene It may also contain one or more selected from the group consisting of: dioxythiophene: dodecylbenzenesulfonic acid, polyaniline: polystyrene sulfonate, polyaniline: camphor sulfonic acid, polypyrrole: polystyrene sulfonate, polypyrrole: camphor sulfonic acid, polypyrrole: toluenesulfonic acid, polypyrrole: dodecylbenzenesulfonic acid, polythiophene: polystyrene sulfonate, polythiophene: camphor sulfonic acid, polythiophene: toluenesulfonic acid, and polythiophene: dodecylbenzenesulfonic acid, and preferably poly(3,4-ethylenedioxythiophene).

[0117] The conductive ink may be an ink in which metal powder and a curable polymer binder are mixed, and the nanowire may be, for example, silver nanowire (AgNW).

[0118] Furthermore, 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 or more structure by combining the aforementioned materials. For example, it may be formed as a two-layer structure including a metal layer and a transparent conductive oxide layer to reduce the reflectance of incident light and increase the transmittance.

[0119] In one embodiment, the transparent conductive layers 200-1 and 200-2 may have a thickness of 1 μm or less, preferably 10 nm to 500 nm, and more preferably 30 nm to 200 nm. In this case, the transparent conductive layers 200-1 and 200-2 can be manufactured as thin light-adjustable laminates without significant changes in properties due to external stress, while ensuring a predetermined transmittance.

[0120] The transparent conductive layers 200-1 and 200-2 of the present invention may not require a separate alignment film because they are physically oriented themselves, or an alignment film may be provided between the transparent conductive layers 200-1 and 200-2 and the liquid crystal layer 300. The alignment film is for adding orientation to the liquid crystal compound, and is preferably photo-oriented. The alignment film may be produced by applying and curing an alignment film coating composition containing an oriented polymer, a photopolymerization initiator, and a solvent. The oriented polymer is not particularly limited, but polyacrylate resins, polyamic acid resins, polyimide resins, polymers containing thinnermate groups, etc., and conventional or subsequently developed polymers capable of exhibiting orientation can be used.

[0121] Liquid crystal layer The liquid crystal layer 300 included in the dimmable 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.

[0122] The liquid crystal layer 300 may contain a liquid crystal compound 310 and may be located, for example, in a space provided by a sealant 400 and / or a spacer (not shown) between the first transparent conductive layer 200-1 and the second transparent conductive layer 200-2 in the light control region.

[0123] The liquid crystal layer 300 can adjust the transmittance of light incident from an external light source by an electric field formed between the first transparent conductive layer 200-1 or the second transparent conductive layer 200-2.

[0124] The liquid crystal compound 310 is not particularly limited as long as it is driven by an electric field and can control the transmittance of light, and conventional or subsequently developed liquid crystal compounds can be used, and for example, the contents of the reactive liquid crystal compounds for coating-type polarizers described above can be applied in the same way.

[0125] The liquid crystal layer 300 is not particularly limited in its liquid crystal behavior method and can be driven by conventional or subsequently developed liquid crystal behavior methods. 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.

[0126] In other embodiments of the present invention, the liquid crystal layer 300 may include one or more spacers selected from the group consisting of ball spacers and column spacers, with ball spacers being particularly preferred. There may be one or more ball spacers, and their diameter is preferably 1 to 10 μm. Furthermore, when viewed from a planar direction, the area occupied by the ball spacers within the liquid crystal layer (i.e., the light adjustment region) is preferably 0.01 to 10% of the area of ​​the liquid crystal layer 300, from the viewpoint of user visibility and improved transmittance in light-transmitting mode, but is not limited thereto.

[0127] sealant The sealant 400 may include a curable resin as a base resin. As the base resin, an ultraviolet-curable resin or a thermosetting resin known to be used as a sealant in the industry may be used. The ultraviolet-curable resin may be a polymer of ultraviolet-curable monomers. The thermosetting resin may be a polymer of thermosetting monomers.

[0128] As the base resin of the sealant 400, for example, an acrylate resin, an epoxy resin, a urethane resin, a phenolic resin, or a mixture of the above resins can be used. In one embodiment, the base resin may be an acrylate resin, and the acrylate resin may be a polymer of an acrylic monomer. The acrylic monomer may be, for example, a polyfunctional acrylate. In other embodiments, the sealant 400 may further contain a monomer component in the base resin. The monomer component may be, for example, a monofunctional acrylate. In this specification, a monofunctional acrylate may mean a compound having one acrylic group, and a polyfunctional acrylate may mean a compound having two or more acrylic groups. The curable resin may be cured by irradiation with ultraviolet light and / or heating. The ultraviolet irradiation conditions or heating conditions may be appropriately carried out within a range that does not impair the purpose of this application. The sealant 400 may further contain an initiator, for example, a photoinitiator or a thermal initiator, if necessary.

[0129] The sealant 400 may be formed by methods commonly used in the art, for example, by drawing the sealant 400 onto the outer periphery (i.e., the inactive region) of the liquid crystal layer using a dispenser equipped with a nozzle.

[0130] The dimmable laminate of the present invention may further include other components as long as it does not impair the purpose of the present invention, for example, it may further include an adhesive layer, an ultraviolet absorbing layer, and the like.

[0131] The adhesive layer may be formed using an adhesive or tack, and preferably has appropriate adhesive strength to prevent peeling, bubbles, etc., from occurring when handling the optical laminate, as well as transparency and thermal stability.

[0132] The adhesive may be a conventional or subsequently developed adhesive, for example, a photocurable adhesive.

[0133] The aforementioned photocurable adhesive exhibits strong adhesive strength upon exposure to active energy rays such as ultraviolet light (UV) or electron beam (EB), undergoing crosslinking and curing. It may be composed of reactive oligomers, reactive monomers, photopolymerization initiators, and the like.

[0134] The reactive oligomer is an important component that determines the properties of the adhesive, forming polymer bonds through a photopolymerization reaction to form a cured film. Examples of usable reactive oligomers include polyester resins, polyether resins, polyurethane resins, epoxy resins, polyacrylic resins, and silicone resins.

[0135] The reactive monomers act as crosslinking agents and diluents for the reactive oligomers mentioned above, affecting their adhesive properties. Examples of usable reactive monomers include monofunctional monomers, polyfunctional monomers, epoxy monomers, vinyl ethers, and cyclic ethers.

[0136] The aforementioned photopolymerization initiator absorbs light energy to generate radicals or cations and initiate photopolymerization, and a suitable one may be selected and used depending on the photopolymerization resin.

[0137] The adhesive may be a conventional or subsequently developed adhesive, and in one or more embodiments, it may be 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, etc. The adhesive is not particularly limited as long as it has adhesive strength and viscoelasticity, but from the viewpoint of availability, it may preferably be an acrylic adhesive, and may contain, for example, a (meth)acrylate copolymer, a crosslinking agent and a solvent.

[0138] The crosslinking agent may be a conventional or subsequently developed crosslinking agent, and may include, for example, polyisocyanate compounds, epoxy resins, melamine resins, urea resins, dialdehydes, methylol polymers, etc. Preferably, it may include polyisocyanate compounds.

[0139] The solvent may include ordinary solvents used in the field of resin compositions, such as alcohol compounds like methanol, ethanol, isopropanol, butanol, and propylene glycol methoxy alcohol; ketone compounds like methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, and dipropyl ketone; acetate compounds like methyl acetate, ethyl acetate, butyl acetate, and propylene glycol methoxy acetate; cellosolve compounds like methyl cellosolve, ethyl cellosolve, and propyl cellosolve; and hydrocarbon compounds like hexane, heptane, benzene, toluene, and xylene. These may be used individually or in combination of two or more.

[0140] The thickness of the adhesive layer can be appropriately determined depending on the type of resin that acts as the adhesive, the adhesive material, and the environment in which the adhesive is used. In one embodiment, the adhesive layer may be 0.01 to 50 μm thick, preferably 0.05 to 20 μm, and more preferably 0.1 to 10 μm thick, in order to ensure sufficient adhesive strength and minimize the thickness of the optical laminate.

[0141] The UV-absorbing layer is not particularly limited as long as it is for preventing degradation of the photochromic laminate due to ultraviolet light, and includes, for example, salicylic acid-based UV absorbers (phenyl salicylate, p-tert-butyl salicylate, etc.), benzophenone-based UV absorbers (2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, etc.), and benzotriazole-based UV absorbers (2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t ert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)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-benzotriazole (2H-2-yl)phenol), 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 chain (and side chain dodecyl)-4-methylphenol, a mixture of octyl-3-[3-tert-butyl-4-hydroxy-5-(chloro-2H-benzotriazole-2-yl)phenyl]propionate and 2-ethylhexyl-3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazole-2-yl)phenyl]propionate, etc.), cyanoacrylate-based UV absorbers (2'-ethylhexyl-2-cyano-3,3-diphenylacrylate, ethyl-2-cyano-3-(3',(e.g., 4'-methylenedioxyphenyl)-acrylate), triazine-based UV absorbers may be used, but benzotriazole-based UV absorbers or triazine-based UV absorbers are preferred because they have high transparency and are excellent at preventing deterioration of polarizing plates and variable transmittance layers, and benzotriazole-based UV absorbers with more appropriate spectral absorption spectra are particularly preferred. The benzotriazole-based UV absorber may be bis(Bis) modified, for example, 6,6'-methylenebis(2-(2H-benzo[d][1,2,3]triazole-2-yl)-4-(2,4,4-trimethylpentan-2-yl)phenol), 6,6'-methylenebis(2-(2H-benzo[d][1,2,3]triazole-2-yl)-4-(2-hydroxyethyl)phenol), etc.

[0142] The polarizing plate of the present invention and the photochromic laminate containing the same can have additional protective films attached to the protective films 120, 120-1, and 120-2, which are positioned at the outermost corners for product protection.

[0143] <Smart windows, automotive and building fixtures> The present invention includes a photochromic laminate containing the polarizing plate described above, as well as a smart window containing the same. By applying the photochromic laminate of the present invention to the smart window, handling during the manufacturing process is made easier and damage and defects can be prevented.

[0144] Furthermore, the present invention includes an automobile to which the smart window is applied to at least one of the following: a front window, a rear window, a side window, a sunroof window, and an interior partition, and building fixtures including the smart window.

[0145] The following describes specific embodiments of the present invention. However, the present invention is not limited to the embodiments disclosed below and can be realized in a variety of different forms, provided that these embodiments are provided to complete the introduction of the present invention and to fully inform a person ordinary skill in the art to which the present invention pertains, and the present invention is defined only by the scope of the claims. [Examples]

[0146] Examples 1-1 to 1-4: Fabrication of polarizing plates (1) Swelling treatment process A 60 μm thick polyvinyl alcohol film (raw material) (manufactured by Kuraray Co., Ltd., product name "Kuraray Poval Film VF-PE#6000", average degree of polymerization 2400, degree of saponification 99.9 mol%) was continuously fed from a raw material roll and transported, then immersed in a swelling bath containing 20°C pure water for 30 seconds. In this swelling process, inter-roll stretching (longitudinal uniaxial stretching) was performed by varying the peripheral speed between the nip rolls. The stretching ratio relative to the raw material film was set to 2.5 times.

[0147] (2) Dyeing process Next, the film that had passed through the nip roll was immersed for 120 seconds in a 30°C dyeing bath containing pure water / potassium iodide / iodine / boric acid (mass ratio) of 100 / 2 / 0.01 / 0.3. In this dyeing treatment as well, inter-roll stretching (longitudinal uniaxial stretching) was performed by varying the peripheral speed between the nip rolls. The stretching ratio, based on the film after the swelling treatment process, was set to 1.1 times.

[0148] (3) Crosslinking process Next, the film that had passed through the nip roll was immersed for 70 seconds in a first crosslinking bath at 56°C with a mass ratio of pure water / potassium iodide / boric acid of 100 / 12 / 4. Inter-roll stretching (longitudinal uniaxial stretching) was performed by creating a difference in peripheral speed between the nip roll and a nip roll prepared between the first and second crosslinking baths. The stretching ratio, based on the film after the dyeing process, was set to 1.9 times.

[0149] (4) Complementary color treatment process Next, the crosslinked film was immersed for 10 seconds in a second crosslinking bath at 40°C with potassium iodide / boric acid / pure water (mass ratio) in a ratio of 9 / 2.9 / 100.

[0150] (5) Washing process Next, the film after the second cross-linking treatment is immersed in a washing bath containing 14°C pure water for 5 seconds, with a shower volume of 5 m³. 3 I washed with a shower at 14°C.

[0151] (6) Drying process Next, the film after the washing process was 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 obtained polarizer film was 25 μm.

[0152] (7) Joining process Next, an aqueous adhesive was prepared containing 5 parts by mass of polyvinyl alcohol per 100 parts by mass of water. Subsequently, a protective film (PET, manufactured by Toyobo, A4360, in-plane phase difference at 550 nm wavelength: 3,200 nm) was laminated onto one surface of the polarizer film using the UV adhesive, and a 38 μm thick phase difference adjustment layer (KC3XR) was laminated onto the other surface of the polarizer film.

[0153] (8) Formation of hard coating layer A hard coating composition was prepared by mixing 16.2 g of a dendrimer compound (MIWON Specialty Chemicals, SP-1106), inorganic nanoparticles (10 to 20 nm, silica particles: 50% by weight, solvent: methyl ethyl ketone (MEK) 14.4 g, polyfunctional (meth)acrylate containing an ethylene glycol group 1.8 g, photoinitiator (1-hydroxycyclohexyl phenyl ketone) 0.7 g, and methyl ethyl ketone 2.9 g).

[0154] The manufactured hard coating composition is bar-coated onto the phase difference adjustment layer using a Meyer bar type, dried at 80°C for 5 minutes, and then heated with a high-pressure mercury lamp at 500 mJ / cm². 2 The material was cured with light at this intensity to form a 12 μm thick hard coating layer.

[0155] The resulting laminate was subjected to UV exposure to cure the adhesive, and the first and second polarizing plates were manufactured identically. The thicknesses of the protective film and polarizing plates are shown in Tables 1 and 2 below.

[0156] Comparative Example 1-1: Fabrication of a polarizing plate The first polarizer and the second polarizer were fabricated in the same manner as in Example 1, except that a TAC (HYOSUNG Corporation, 60 μm TAC, in-plane phase difference at 550 nm wavelength: 0.5 nm) film was used as the protective film.

[0157] Comparative Example 1-2: Fabrication of Polarizing Plates The first polarizer and the second polarizer were fabricated in the same manner as in Example 1, except that a PET film with a thickness of 50 μm (PET, manufactured by Toyobo, A4360, in-plane phase difference at a wavelength of 550 nm: 3,200 nm) was used as the protective film.

[0158] Experimental Example 1: Evaluation of the physical properties of polarizing plates (1) Amount of color change The first polarizing plates produced in Examples 1-1 to 1-4 and Comparative Examples 1-1 to 1-2 were cut to 4 cm x 4 cm, and samples were prepared by applying an adhesive layer to the hard coating layer side and attaching it to glass. Hues a* and b* were measured using a spectrophotometer (JASCO, V-7100), and the samples were placed in an oven (JEIOTECH, TH-TG) and left at 40°C and 93% RH for 24 hours. The hues after this period were measured in the same manner, and the amount of color change (ΔE) was calculated using Equation 2 below. The results are shown in Table 1 below.

[0159] [Formula 2] ΔE = {(Δa*)} 2+(Δb*) 2} 1 / 2 (2) Moisture permeability The first polarizing plates produced in Examples 1-1 to 1-4 and Comparative Examples 1-1 to 1-2 were cut to 4cm x 4cm, and the change in weight before and after 24 hours of standing under high humidity conditions (40°C / 90%RH) was measured using the moisture permeability evaluation method (JIS Z 0208). The moisture permeability was calculated as [change in weight (g) / moisture permeable area (m²)]. 2 The calculation was performed using the formula ) / day, and the results are shown in Table 1 below.

[0160] (3) Handling The first polarizing plates manufactured in Examples 1-1 to 1-4 and Comparative Examples 1-1 to 1-2 were cut to 10 cm x 5 cm with the MD direction as the longer side. Mandrel evaluation was performed using a mandrel bending test device (MT-3440, manufactured by M-Tech) with the hard coating layer facing inward, mounted in a mandrel holder. The maximum diameter at which no cracks occurred in the first polarizing plate while bending the mandrel 180° with varying diameters is shown in Table 1 below.

[0161] [Table 1]

[0162] Manufacturing Example 1: Fabrication of a transparent conductive layer In Examples 1-1 to 1-4 and Comparative Examples 1-1 to 1-2, the PEDOT functional conductive layer formation composition was applied to the first hard coating layer and the second hard coating layer of the first polarizing plate and the second polarizing plate, respectively. By drying at 90°C for about 5 to 10 minutes to form a functional conductive layer and then physically oriented it, the first transparent conductive layer and the second transparent conductive layer were formed, respectively.

[0163] In this instance, the composition for forming the PEDOT functional conductive layer was a mixture of 0.6% by weight of PEDOT:PSS, 32.4% by weight of ethyl alcohol, 40% by weight of deionized water, and 27% by weight of 2-methoxyethanol.

[0164] Manufacturing Example 2: Ball Spacer Dispensing A mixed solvent was prepared by mixing 0.03 g of ball spacers (SP series manufactured by SEKISUI) with 100 ml of isopropyl alcohol (IPA). Next, the laminates produced through Examples 1-1 to 1-4, Comparative Examples 1-1 to 1-2, and Production Example 1 were placed in a spacer sprayer (SDSS-KHU02 manufactured by SHINDO ENG LAB), and the mixed solvent was sprayed at 110°C. After drying for 20 minutes, ball spacers were formed on the first transparent conductive layer.

[0165] Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-2: Fabrication of dimmable laminates In each laminate produced through Examples 1-1 to 1-4 and Comparative Examples 1-1 to 1-2, and Production Examples 1 and 2, a sealant (UVF-006, 70,000 mPa·s, manufactured by SEKISUI) was formed on the outer surface of the first transparent conductive layer by drawing it through a sharp needle (SPN-0.25-12.7L) at a discharge pressure of 200 mPa using a sealant dispenser (SHOTmini 200Ωx, manufactured by MUSASHI).

[0166] A liquid crystal layer was formed in the sealant on the first transparent conductive layer by injecting liquid crystal (HCCH Corporation, HPC21600) using the ODF process method.

[0167] The second polarizing plate and the second transparent conductive layer are bonded to the first polarizing plate and the first transparent conductive layer, with the sealant and liquid crystal layer in between, facing each other, and the polarization axes of the first polarizing plate and the second polarizing plate are arranged parallel to each other at 0° or 90°, with a load of 3 kg / cm². 2 The dimmable laminate was manufactured by joining the layers under pressure to form the laminated structure shown in Figure 3. Subsequently, conductive copper tape (TERAOKA, No. 8323) was bonded to the first transparent conductive layer and the second transparent conductive layer to connect them.

[0168] Experimental Example 2: Evaluation of the physical properties of a light-adjustable laminate. (1) Measurement of step height The dimmable laminate samples produced through Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-2 were fixed onto soda-lime glass with the first protective film of the first polarizing plate facing upwards. The step difference between the sealant region and the liquid crystal region, observed on the surface of the first protective film of the fixed sample, was measured using an interference microscope (KEYENCE VK-X3000). The measurement magnification was 10x, and the measurement mode was VSI mode (vertical scanning interferometer). The scan range was set to 50 μm in the thickness direction of the sample, and the value with the largest height difference was measured as the step difference between the non-display region and the display region. The results are shown in Table 2 below.

[0169] (2) Evaluation of reliability 1) Evaluation of appearance Samples were prepared by fixing both sides of the dimmable laminates manufactured through Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-2 with glass. After 1,000 hours under high humidity conditions (60°C / 90%RH), the appearance was visually inspected to confirm the number of defects such as spots and bubbles. The size of each defect was confirmed using an OLYMPUS MX61 optical microscope, and the size of the largest defect was recorded. The defects were then evaluated according to the defect evaluation criteria below, and the results are shown in Table 2 below.

[0170] <Criteria for evaluating defects in appearance> ◎: Number of defective items: 2 or less / Defect size: 0.1 mm or less ○: Number of defective items exceeds 2, but is 5 or less / Defect size exceeds 0.1 mm, but is 0.3 mm or less △: Number of defective items exceeds 5, but is 10 or less / Defect size exceeds 0.3 mm, but is 0.7 mm or less ×: Number of defective items exceeds 10 / Defect size exceeds 0.7 mm 2) Evaluation of optical performance Samples were prepared by fixing both sides of the dimmable laminates manufactured through Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-2 with glass. After 1,000 hours under high humidity conditions (60°C / 90%RH), the transmittance change rate was measured using a spectroscopic colorimeter (CM-3700d, Konica Minolta), and the optical performance was evaluated according to the evaluation criteria below. The results are shown in Table 2 below.

[0171] <Evaluation Criteria for Optical Performance> ◎: Transmittance change rate of 1% or less ○: Transmittance change rate exceeding 1%, 2% or less. △: Transmittance change rate exceeds 2%, but is 3% or less. ×: Transmittance change rate exceeding 3%, 4% or less.

[0172] [Table 2]

[0173] As a result of the evaluation of the physical properties in Tables 1 and 2 above, it was confirmed that when the thickness of the protective film located on the outermost edge of the polarizing plate of the present invention satisfies the range of 100 μm to 300 μm, the amount of color change and moisture permeability under high temperature and high humidity conditions are low, resulting in excellent heat and humidity resistance, as well as good handling properties. In the dimmable laminate to which this is applied, the occurrence of steps due to the liquid crystal layer and sealant is minimized, and defects such as unevenness and bubbles due to the occurrence of steps do not occur. Furthermore, even when a thick protective film is applied, the optical properties under high humidity conditions are maintained, and it was confirmed that the product is highly reliable.

[0174] In contrast, in the case of a comparative example where the thickness of the protective film located on the outermost edge of the polarizing plate does not satisfy the aforementioned range, the amount of color change and moisture permeability under high temperature and high humidity conditions are not as good as in the example. It can be confirmed that the step difference between the liquid crystal layer and the sealant in the dimmable laminate containing this is much larger than in the example, which can be seen as leading to the occurrence of defects and a decrease in visibility.

Claims

1. A polarizer; and a polarizing plate for a photochromic laminate, comprising a protective film formed on one surface of the polarizer, The protective film is characterized by having a thickness of 100 μm to 300 μm, and is a polarizing plate for a photochromic laminate.

2. The polarizing plate for a photochromic laminate according to claim 1, wherein the polarizing plate has a thickness of 150 μm to 500 μm.

3. The polarizing plate for a photochromic laminate according to claim 1, wherein the protective film has an in-plane phase difference of less than 4000 nm for light with a wavelength of 550 nm.

4. 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; A liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer; and Includes a sealant formed along the outer surface of the liquid crystal layer, At least one of the first transparent conductive layer and the second transparent conductive layer is formed in direct contact with either the first polarizer or the second polarizer. A light-adjustable laminate comprising a first polarizing plate and a second polarizing plate, each having a first protective film and a second protective film on the surfaces where the first transparent conductive layer and the second transparent conductive layer are not formed, and each of the first protective film and the second protective film having a thickness of 100 μm to 300 μm.

5. The photochromic laminate according to claim 4, wherein the first polarizing plate and the second polarizing plate each have a thickness of 150 μm to 500 μm.

6. The dimmable laminate according to claim 4, wherein the first protective film and the second protective film have an in-plane phase difference of less than 4000 nm with respect to light with a wavelength of 550 nm.

7. The photochromic laminate according to claim 4, wherein at least one of the first polarizing plate and the second polarizing plate further includes a first phase difference adjustment layer or a second phase difference adjustment layer on the surface on which the first protective film or the second protective film is not formed.

8. The photochromic laminate according to claim 4, 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 hard coating layer and a refractive index adjusting layer on the phase difference adjusting layer.

9. The light-adjustable laminate according to claim 4, wherein at least one of the first transparent conductive layer and the second transparent conductive layer is formed in direct contact with either the first polarizer or the second polarizer, without including a separate substrate between them.

10. The light-adjustable laminate according to claim 4, wherein at least one of the first transparent conductive layer and the second transparent conductive layer includes an easy-adhesion layer between itself and either one of the first polarizer and the second polarizer, and is formed in direct contact with it.

11. A smart window comprising the dimmable laminate described in claim 4.

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