Variable transmittance optical laminate and sunroof comprising same

Abstract

The present invention relates to a variable transmittance optical laminate and a sunroof comprising the same, the variable transmittance optical laminate comprising: a dimming laminate comprising an electric field-driven liquid crystal between polarizing plates; and a shutter-type film disposed on at least a portion of the indoor side of the light-dimming laminate, the shutter-type film being formed by laminating two or more layers and including a light-shielding pattern, and the light-shielding pattern being disposed so as to face the indoor side. The variable-transmittance optical laminate according to the present invention exhibits an excellent anti-reflection function without reducing the transmittance of external light by means of a shutter-type film comprising a light-shielding pattern protruding toward the indoor side and having two or more layers laminated therein.

Description

Technical Field

[0001] The present invention relates to a variable transmittance optical laminate and a skylight including the same. Background Art

[0002] Generally, an external light blocking coating is often applied to the glass windows of moving tools such as vehicles. However, the transmittance of the glass windows of traditional moving tools is fixed, and the transmittance of the external light blocking coating is also fixed. Therefore, since the overall transmittance of the windows of such traditional moving tools is fixed, accidents may occur. For example, if the overall transmittance is set low, there is no problem during the day when the surrounding light is sufficient. However, in situations such as at night when the surrounding light is insufficient, there is a problem that it is difficult for the driver or the like to correctly view the surroundings of the moving tool. In addition, if the overall transmittance is set high, there is a problem that glare may occur to the driver or the like during the day when the surrounding light is sufficient. For this reason, a variable transmittance optical laminate that can change the light transmittance when a voltage is applied has been developed.

[0003] On the other hand, in a social atmosphere that emphasizes privacy protection, attempts have been made to impart an antireflection function to glass windows. In particular, in the case of the skylight of a vehicle, there is a problem that the reflected image of the front seat panel reflected from the skylight during night driving causes glare to the field of view of the rear seat passengers. Therefore, when applying a variable transmittance optical laminate to a skylight or the like, not only a transmittance adjustment function but also an improvement in the antireflection function during night driving or the like is required.

[0004] For this reason, a technique of attaching a coating having an antireflection function to one or both sides of an optical laminate has been developed. For example, Korean Patent Publication No. 1999-0028992 discloses a window glass having an antireflection coating, specifically a window glass including layers of materials having high and low refractive indices of two or more layers.

[0005] However, in the case of introducing a multi-layer coating layer to impart an antireflection function in this way, there are problems that the thickness of the optical laminate becomes thick and the transmittance adjustment performance decreases, or the manufacturing process becomes complicated. In addition, when applying such a coating to a laminate that must include a liquid crystal layer or a polarizing plate and includes an electric field-driven liquid crystal between the polarizing plates, since the overall thickness of the laminate becomes too thick, it is not suitable for application to vehicles or buildings.

[0006] Therefore, in reality, it is necessary to develop an optical laminate that has an antireflection function without reducing the transmittance of external light, has a thin thickness and is advantageous for bending characteristics, and a skylight including the same.

[0007] Prior Art Documents

[0008] Patent Documents

[0009] Patent Document 1: Korean Published Patent No. 1999-0028992 Summary of the Invention

[0010] Problems to be Solved

[0011] An object of the present invention is to provide an optical laminate that has an antireflection function without reducing the transmittance of external light, is thin in thickness, and is advantageous for bending characteristics, and a skylight including the same.

[0012] Means for Solving the Problems

[0013] To achieve the above object, the present invention provides a variable transmittance optical laminate including: a dimming laminate including an electric field-driven liquid crystal between polarizing plates; and a shutter film disposed on at least a part of the indoor side of the dimming laminate, wherein two or more layers of the shutter film are laminated and include a light-shielding pattern disposed toward the indoor side.

[0014] In one embodiment of the present invention, two or more layers of the shutter film are laminated, and may include a second adhesion surface on the indoor side and a first adhesion surface between the second adhesion surface and the dimming laminate, and the light-shielding pattern of the second adhesion surface may protrude toward the indoor side.

[0015] In another embodiment of the present invention, the first adhesion surface may include a first light-shielding pattern, the second adhesion surface may include a second light-shielding pattern, and in a vertical cross-section, a straight line connecting the outermost point where the first light-shielding pattern meets the first adhesion surface and the corresponding outermost point where the second light-shielding pattern meets the second adhesion surface may be inclined with respect to the first adhesion surface and form a predetermined inclination angle θ with the adhesion surface.

[0016] In another embodiment of the present invention, in a vertical cross-section, the length a of the straight line obtained by projecting the inclined line connecting the outermost point where the first light-shielding pattern meets the first adhesion surface and the outermost point of the corresponding second light-shielding pattern onto the first adhesion surface may be 5 to 50% of the length ω1 of the first light-shielding pattern.

[0017] In one embodiment of the present invention, the range of the maximum viewing angle θ1 of the reflected image of the variable transmittance optical laminate may be 40° to 75°, and the viewing angle of the reflected image is the angle of the reflected image with respect to a straight line perpendicular to the adhesion surface on the indoor side in the vertical cross-section of the variable transmittance optical laminate.

[0018] In one embodiment of the present invention, the range of the maximum viewing angle θ2 of the external light transmitted from the outside through the variable transmittance optical laminate may be 60° to 85°, and the viewing angle of the above-mentioned external light is the angle of the external light relative to the straight line perpendicular to the adhesion surface on the indoor side in the vertical cross-section of the variable transmittance optical laminate.

[0019] In one embodiment of the present invention, the above-mentioned louvered film may be formed by joining at least two or more adhesion surfaces through an adhesive / binder.

[0020] In one embodiment of the present invention, the above-mentioned louvered film includes a pattern interval ω2 where the above-mentioned light shielding pattern is not formed on the adhesion surface and a light shielding portion where the above-mentioned light shielding pattern is formed on the adhesion surface. When the height of the above-mentioned second light shielding pattern is set to h2, the shortest straight-line distance between the above-mentioned adhesion surfaces is set to h3, and the length of the above-mentioned first light shielding pattern is set to ω1, the value of (h2 + h3) / ω1 may be 0.5 to 4.0. Based on the direction perpendicular to the plane, the aperture ratio (p) defined by ω3 / (ω2 + ω1)×100(%) may be 70% or more.

[0021] In another embodiment of the present invention, the dimming laminate may include a first polarizing plate, a first transparent conductive layer formed on one surface of the first polarizing plate, a second polarizing plate opposite to the first polarizing plate, a second transparent conductive layer formed on one surface of the second polarizing plate and opposite to the first transparent conductive layer, and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer. At least one of the first transparent conductive layer and the second transparent conductive layer may be formed in direct contact with one of the first polarizing plate and the second polarizing plate.

[0022] In another embodiment of the present invention, at least one of the first transparent conductive layer and the second transparent conductive layer may include one or more selected from the group consisting of transparent conductive oxides, metals, carbon-based materials, conductive polymers, conductive inks, and nanowires.

[0023] In another embodiment of the present invention, at least one of the first polarizing plate and the second polarizing plate may include one or more functional layers selected from the group consisting of a protective layer, a retardation adjusting layer, and a refractive index adjusting layer.

[0024] In another embodiment of the present invention, at least one of the first polarizing plate and the second polarizing plate may have a thickness of 30 μm to 200 μm.

[0025] In another embodiment of the present invention, the liquid crystal layer may include one or more spacers selected from the group consisting of ball spacers and column spacers.

[0026] In another embodiment of the present invention, an alignment film may also be included on both surfaces of the liquid crystal layer.

[0027] The present invention provides a sunroof including the above-described variable transmittance optical laminate.

[0028] Advantages of the Invention

[0029] According to an embodiment of the present invention, an optical laminate, by including a shutter-type film formed by laminating two or more layers and including a light-shielding pattern protruding toward the indoor side, exhibits an excellent antireflection function while not reducing the transmittance of external light.

[0030] According to an embodiment of the present invention, an optical laminate can provide an optical laminate having a thin overall thickness and being advantageous for bending characteristics because a transparent conductive layer is directly formed on the polarizer itself to enable a form of direct contact therewith, rather than the transparent conductive layer being formed through a separate substrate and attached to the polarizer.

[0031] In addition, as described above, since the overall thickness of the optical laminate is reduced, in the case of applying the shutter-type film having a unique structure of the present invention, there is an advantage that the antireflection function and the transmittance adjustment function can be maximized.

[0032] Furthermore, as described above, since the overall thickness of the optical laminate is reduced, in the case of applying the shutter-type film having a unique structure of the present invention, it is advantageous even when stacking multiple shutter-type films.

[0033] Furthermore, when the variable transmittance optical laminate of the present invention is used as a sunroof, it is possible to improve the phenomenon in which the reflected image of the front seat panel reflected from the sunroof dazzles the view of the rear seat passengers during night driving. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1a and Figure 1b are diagrams showing the laminate structure of a variable transmittance optical laminate according to an embodiment of the present invention.

[0035] Figure 2 are diagrams showing the laminate structure of a shutter-type film according to an embodiment of the present invention.

[0036] Figure 3 are diagrams showing the travel of external light and reflected light reaching a shutter-type film according to one or more embodiments of the present invention.

[0037] Figure 4 It is a diagram showing the substantial inclination and its angles of a light-shielding pattern formed by laminating multiple adhesion surfaces according to an embodiment of the present invention.

[0038] Figure 5a and 5b It is a diagram showing the change in viewing angle of external light reaching a louvered film due to the difference in the shortest distance between the light-shielding pattern configuration and the adhesion surface according to one or more embodiments of the present invention.

[0039] Figure 6a and 6b It is a diagram showing the change in viewing angle of the reflected light reaching a louvered film due to the difference in the shortest distance between the light-shielding pattern configuration and the adhesion surface according to one or more embodiments of the present invention.

[0040] Figure 7 It is a diagram showing the reflected light when the viewing angle of the reflected image in a transmittance-variable optical laminate formed by laminating multiple adhesion surfaces is maximum according to an embodiment of the present invention.

[0041] Figure 8 It is a diagram showing the visual field range of a subject determined based on the maximum viewing angle range θ1 of the reflected image and the maximum viewing angle range θ2 of external light of the above-mentioned transmittance-variable optical laminate.

[0042] Figures 9a - 9e It is a diagram showing the laminated structure of a polarizing plate according to one or more embodiments of the present invention.

[0043] Symbol Explanation

[0044] 100: Dimming laminate

[0045] 200: Polarizing plate

[0046] 210: Polarizer

[0047] 220: Protective layer

[0048] 230: Phase difference adjustment layer

[0049] 240: Refractive index adjustment layer

[0050] 300: Transparent conductive layer

[0051] 400: Liquid crystal layer

[0052] 500: Alignment film

[0053] 600: Sealant

[0054] 700: Louvered film

[0055] 700-1: First louvered film

[0056] 700-2: Second louvered film

[0057] 710: Adhesive surface

[0058] 710-1: First adhesive surface

[0059] 710-2: Second adhesive surface

[0060] 720: Light-shielding pattern

[0061] 720-1: First light-shielding pattern

[0062] 720-2: Second light-shielding pattern Detailed implementation mode

[0063] The present invention relates to a variable transmittance optical laminate and a smart window and a skylight including the same. The variable transmittance optical laminate is not only thin in thickness and beneficial to bending characteristics, but also can have an antireflection function while effectively adjusting the transmittance of external light. Therefore, when driving at night, it significantly improves the glare caused by the reflected image of the front seat panel reflected from the skylight to the rear seat passengers' field of vision.

[0064] More specifically, the main feature of the present invention is that by including a louvered film in which two or more layers of louvered films having light-shielding patterns are laminated and the light-shielding patterns are arranged so as to protrude toward the indoor side, the viewing angle range of the reflected image can be adjusted.

[0065] The variable transmittance optical laminate of the present invention is particularly suitable for the technical field capable of changing the light transmittance according to the application of voltage. For example, it can be used for smart windows, etc.

[0066] A so-called smart window is an optical structure that changes the light transmittance according to the application of an electric signal to control the amount of light or heat passing through. That is, a smart window can change into a transparent, opaque or translucent state according to voltage, and is also called variable transmittance glass, dimming glass or smart glass, etc.

[0067] Smart windows can be used as partitions for dividing the interior space of vehicles and buildings or partitions for privacy protection, or as daylighting windows arranged at the openings of buildings, and can also be used as highway road signs, billboards, scoreboards, clocks or advertising screens, and can be used instead of the glass of transportation tools such as the windows or skylights of automobiles, buses, airplanes, ships or trains.

[0068] The variable transmittance optical laminate of the present invention can also be used as a smart window in the above technical fields. However, since the conductive layer is directly formed on the polarizing plate without including a separate substrate for forming the conductive layer, it has a thin thickness and is advantageous for bending characteristics, and can be particularly suitable for smart windows for vehicles or buildings. In one or more embodiments, the smart window using the variable transmittance optical laminate of the present invention can be used for transportation means, such as the front window, rear window, side window, and sunroof of an automobile, or building windows. In addition to the use of blocking external light, it can also be used for internal space partitioning or privacy protection purposes in an automobile or a building, such as an internal partition, and can also be used for wearable devices such as helmets, glasses, or watches. More specifically, the variable transmittance optical laminate of the present invention is characterized in that it can not only adjust the external light transmitted but also block the light reflected from adjacent positions, thereby maximizing the privacy protection function. In particular, when the variable transmittance optical laminate of the present invention is used as the sunroof of a vehicle, it has the following advantages: not only is it thin and advantageous for bending characteristics, but it also has an antireflection function without reducing the transmittance of external light, so that the glare caused by the reflected image of the front seat panel reflected from the sunroof on the field of view of the rear seat passengers is significantly improved during night driving.

[0069] Hereinafter, embodiments of the present invention will be described more specifically with reference to the accompanying drawings. However, the following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further understand the above-described invention content and the technical idea of the present invention. Therefore, the present invention should not be construed as being limited only to the matters described in these drawings.

[0070] The terms used in this specification are intended to describe the embodiments and are not intended to limit the present invention. In this specification, unless otherwise specifically mentioned in the context, the singular form also includes the plural form. For example, the "polarizing plate" used in this specification may refer to at least one of the first polarizing plate and the second polarizing plate, and the "transparent conductive layer" may refer to at least one of the first transparent conductive layer and the second transparent conductive layer.

[0071] The terms "comprises" and / or "comprising" used in this specification are used in the sense of not excluding the presence or addition of one or more other elements, steps, operations, and / or components other than the recited elements, steps, operations, and / or components. Throughout the specification, the same reference numerals refer to the same components.

[0072] As illustrated in the accompanying drawings, spatially relative terms such as "lower", "bottom surface", "lower part", "upper", "upper surface", "upper part", etc. may be used to easily describe the relative relationship between one element or component and other elements or components. Spatially relative terms should be understood as terms that include different directions from each other when the element is in use or operation, in addition to the directions illustrated in the drawings. For example, in the case of flipping the element illustrated in the drawings, the element described as "lower" or "lower part" of other elements may be placed "above" other elements. Therefore, the exemplary term "lower" may include both the lower and upper directions. The element may also be oriented in other directions, so spatially relative terms may be interpreted according to the orientation.

[0073] The "top view direction" used in this specification may be interpreted as the direction orthogonal to the polarizing plate and / or the transparent conductive layer, that is, the direction observed from the visible side of the user. In addition, the "vertical direction" used in this specification may be the thickness direction of the polarizing plate and / or the transparent conductive layer, that is, the direction orthogonal to the "top view direction" along the direction observed from the visible side of the user. In addition, the "vertical cross-section" may refer to the cross-section when the transmittance variable optical laminate of the present invention is cut along the vertical direction.

[0074] The "indoor side" used in this specification may refer to the visible side of the main user. For example, when the transmittance variable optical laminate is applied to a vehicle, it may refer to the visible side of the passenger, that is, the inner side of the vehicle. When the transmittance variable optical laminate is applied to a building, it may refer to the visible side of the user inside the building, that is, the inner side of the building, but is not limited thereto. The "outdoor side" or "outside" is a concept opposite to the indoor side, and based on the transmittance variable optical laminate, it may refer to the opposite side of the visible side of the main user.

[0075] <Transmittance Variable Optical Laminate>

[0076] Figure 1a and Figure 1b is a diagram showing the laminated structure of the transmittance variable optical laminate according to an embodiment of the present invention (the inclined light shielding pattern is not shown).

[0077] The transmittance variable optical laminate of the present invention is characterized by comprising: a dimming laminate 100, which contains an electric field-driven liquid crystal between polarizing plates; and a shutter film 700, which is disposed on at least a part of the indoor side of the above dimming laminate. In particular, two or more layers of the above shutter film 700 are laminated, and the above shutter film 700 contains a light shielding pattern 720, and the above light shielding pattern 720 protrudes toward the indoor side.

[0078] The adhesion surface of the present invention refers to the layer to which the light-shielding pattern 720 of the above-mentioned louver film 700 adheres. As an example, when the light-shielding pattern 720 of the louver film 700 of the present invention is directly formed on the light control laminate 100 without additional substrates or films, the above-mentioned adhesion surface can be one side of the light control laminate 100, preferably the indoor side one side of the light control laminate 100. For example, it can be a polarizing plate 200, a polarizer 210, a protective layer 220, the stacked retardation adjusting layer 230 or the refractive index adjusting layer 240. In another example of the present invention, when the light-shielding pattern 720 of the louver film 700 of the present invention is formed on an additional substrate or film such as a transparent film and adheres to the light control laminate, the above-mentioned adhesion surface can be an additional substrate or film such as a transparent film.

[0079] Louver film 700

[0080] Figure 2 It is a diagram showing the laminated structure of the louver film of an embodiment of the present invention.

[0081] The variable transmittance optical laminate of the present invention includes a louver film 700 disposed on at least a part of the indoor side of the light control laminate, and the above-mentioned louver film 700 must include a light-shielding pattern 720.

[0082] In addition to the light-shielding pattern 720, the louver film 700 of the present invention may not include additional substrates or films for supporting the light-shielding pattern 720. In this case, the above-mentioned light-shielding pattern 720 can be directly formed on one side of the light control laminate 100. In this case, the above-mentioned light-shielding pattern 720 is formed on the indoor side one side of the light control laminate 100 and protrudes toward the indoor side. The louver film 700 of the present invention can directly form the light-shielding pattern 720 on the indoor side one side of the light control laminate 100. In this case, it has the advantage of minimizing the overall thickness of the variable transmittance optical laminate of the present invention. A method of pre-forming a pattern including a release layer and then transferring it through an adhesion surface and an adhesive / binder can be used. At this time, as the thickness of the adhesive / binder is minimized, the overall thickness of the variable transmittance optical laminate will become thinner.

[0083] In addition, as Figure 1b shown, in addition to the light-shielding pattern 720, the louver film 700 of the present invention may further include additional substrates or films for supporting the light-shielding pattern 720, preferably a transparent film may be further included.

[0084] The above-mentioned louvered film 700 is characterized in that it is laminated with two or more layers, and includes a second adhesion surface 710-2 on the indoor side and a first adhesion surface 710-1 between the second adhesion surface 710-2 and the dimming laminate. The light-shielding pattern 720-2 of the second adhesion surface 710-2 protrudes toward the indoor side.

[0085] More specifically, the first adhesion surface 710-1 includes a first light-shielding pattern 720-1, and the second adhesion surface 710-2 includes a second light-shielding pattern 720-2. As Figure 2 shown, in a vertical cross-section, the straight line connecting the outermost point where the first light-shielding pattern 720-1 meets the first adhesion surface 710-1 and the outermost point where the corresponding second light-shielding pattern 720-2 meets the second adhesion surface 710-2 may be an oblique line with respect to the first adhesion surface and form a predetermined inclination angle θ with the adhesion surface, but it is not limited thereto.

[0086] On the other hand, the present invention is characterized in that the first light-shielding pattern 720-1 and the corresponding second light-shielding pattern 720-2 are arranged offset from each other in a plane, so that the light-shielding pattern 720 is inclined at a predetermined angle with respect to the adhesion surface in a vertical cross-section. The meaning of the inclination includes substantial inclination. In the present invention, the meaning of substantial inclination may refer to the overall shape of the light-shielding pattern 720 being inclined in the direction toward the user in a vertical cross-section. Hereinafter, in this specification, the "overall shape of the light-shielding pattern 720" refers to the shape of the light-shielding pattern formed by the corresponding plurality of light-shielding patterns 720 on the first adhesion surface 710-1 and the second adhesion surface 710-2. As an example, it may be Figure 2 and Figure 4 ~the trapezoidal shape formed by the first light-shielding pattern 720-1 and the corresponding second light-shielding pattern 720-2 shown in FIG. 5.

[0087] More specifically, referring to Figure 2 , in the cross-section of the louvered film 700 of the present invention, the first adhesion surface 710-1 includes a shape in which the first light-shielding pattern 720-1 having a predetermined height h1 and length ω1 is formed repeatedly at a predetermined interval ω2 on the first adhesion surface 710-1, and the second adhesion surface 710-2 includes a shape in which the second light-shielding pattern 720-2 having a predetermined height h2 and length ω4 is formed repeatedly at a predetermined interval ω2 on the second adhesion surface 710-2. Figure 2, ω1 and ω4 are the same, h1 and h2 are the same, and the spacing between the first light-shielding patterns and the spacing between the second light-shielding patterns are the same, but the scope of the present invention is not limited thereto. At this time, since the overall shape of the light-shielding pattern of the present invention is formed obliquely relative to the adhesive surface due to the corresponding multiple light-shielding patterns 720 on the first adhesive surface 710-1 and the second adhesive surface 710-2, based on the direction perpendicular to the multiple adhesive surfaces, a predetermined vertical light-transmitting portion ω3 without a pattern may be included.

[0088] More specifically, the overall shape of the shading pattern 720 of the present invention caused by the multiple shading patterns included in the louver-type film stacked with more than two layers of the present invention is inclined at a predetermined angle relative to the above-mentioned adhesive surface in a vertical section, which means that due to the stacking of multiple adhesive surfaces, the shape formed by the multiple shading patterns is not perpendicular to the above-mentioned adhesive surface, but forms an angle.

[0089] More specifically, the shading pattern 720 of the present invention may be tilted in a direction toward the user in a vertical cross section. For example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, the shading pattern 720 may be tilted in a direction toward the rear seat passengers. Therefore, the transmittance loss of external light to the rear seat passengers of the vehicle is minimized, and the glare caused by the reflected image to the rear seat passengers' field of vision is significantly improved.

[0090] The light shielding pattern 720 attached to the adhesive surface 710 may be arranged to face the indoor side. Figure 2 The second light shielding pattern 720-2 may protrude toward the indoor side.

[0091] The above-mentioned shading pattern can be one of polygonal, circular, semicircular, dotted, straight, oblique, wavy, toothed, and grid shapes, and its cross-sectional shape is not particularly limited as long as the effect of the present application can be achieved.

[0092] In the two or more layers of the louver film of the present invention, the adhesive surfaces are stacked with the shortest straight line distance h3 between them, and a tackiness agent / adhesive may be further included and stacked between the two or more layers of the louver film.

[0093] In the present invention, the light shielding patterns of two or more louver films corresponding to each other may be arranged to be offset at a predetermined distance in a vertical cross section.

[0094] More specifically, in a vertical cross-section, there is a length of the oblique line connecting the outermost point where the first light-shielding pattern meets the first adhesion surface and the outermost point of the corresponding second light-shielding pattern projected onto the first adhesion surface, that is, the oblique line projection length a. In addition, referring to Figure 7 , the above-mentioned oblique line projection length a can be regarded as the length obtained by subtracting the vertical light-transmitting portion ω3 from the pattern pitch ω2 between the first light-shielding patterns. The above a can be 5 to 50% of the length ω1 of the first light-shielding pattern. When the pattern sizes are the same, the smaller the angle θ of the overall shape of the light-shielding pattern 720 with respect to the adhesion surface, the longer the oblique line projection length a.

[0095] The variable transmittance optical laminate according to an embodiment of the present invention can not only adjust the shapes and specifications of the first light-shielding pattern 720-1 and the second light-shielding pattern 720-2, but also adjust the maximum viewing angle θ1 of the reflected image and the maximum viewing angle θ2 of external light according to the degree of misalignment of the patterns determined by the pattern pitch ω2, the vertical light-transmitting portion ω3, the oblique line projection length a, and / or the shortest straight-line distance h3 between adjacent adhesion surfaces.

[0096] Figure 3 It is a diagram showing the travel of external light (solid arrows) and reflected light (dashed arrows) reaching the louvered film according to one or more embodiments of the present invention.

[0097] In the louvered film 700 of the variable transmittance optical laminate of the present invention, since the light-shielding pattern 720-2 on the adhesion surface, especially on the indoor side, protrudes inward in two or more layers of louvered films, the reflected light can be blocked by the side surface of the light-shielding pattern. Thus, the viewing angle range of the reflected image can be adjusted by making only the reflected image not blocked by the side surface of the above-mentioned light-shielding pattern 720-2 visible.

[0098] Different from the conventional polarizing panel that controls external light by introducing a separate polarizing layer and relying on the physical properties within the polarizing layer, the variable transmittance optical laminate of the present invention absorbs light by means of the physical structure of the light-shielding pattern, thereby preventing the reflected light from reaching the observer.

[0099] Referring to Figure 3 , the louvered film 700 of the variable transmittance optical laminate of the present invention is laminated with two or more layers. According to the shortest straight-line distance h3 between the adhesion surfaces of each layer with the light-shielding pattern and the degree of misalignment of the light-shielding patterns of each layer, the viewing angle range θ2 of the external light transmitted from the outside can be adjusted.

[0100] Specifically, in the variable transmittance optical laminate according to an embodiment of the present invention, the angle range at which external light passes through the louvered film 700 can be determined according to the angle formed by the straight line connecting the outermost points of the first light-shielding pattern and the second light-shielding pattern and the straight line perpendicular to the adhesion surface 710.

[0101] In addition, referring to Figure 3 , since a part of the reflected light reflected from the indoor side is absorbed by the light-shielding pattern according to the angle, the viewing angle of the reflected light can be adjusted according to the shape or size of the light-shielding pattern 720.

[0102] Hereinafter, the viewing angle range of external light and the viewing angle range of reflected light of the transmissivity variable optical laminate according to an embodiment of the present invention will be described in more detail through Figures 4 - 6b .

[0103] Figure 4 FIG. is a diagram showing the substantial inclination and angle formed by the lamination of a plurality of adhesion surfaces of the light-shielding pattern according to an embodiment of the present invention. At this time, the length of the diagonal line connecting the outermost point where the first light-shielding pattern is in contact with the first adhesion surface and the corresponding outermost point where the second light-shielding pattern is in contact with the second adhesion surface projected onto the first adhesion surface is called the diagonal projection length a.

[0104] Referring to Figure 4 , when the diagonal projection length a is used as the base of a right triangle and the shortest straight-line distance h3 between the first adhesion surface and the second adhesion surface is used as the height of the right triangle, the viewing angle range of external light of the transmissivity variable optical laminate of the present invention can be adjusted according to the inclination angle (hereinafter, referred to as θ.) determined by the degree of misalignment of the light-shielding patterns of the laminated adhesion surfaces.

[0105] The angle formed by the hypotenuse and the base of the right triangle is the angle formed by the line connecting the outermost points of the first light-shielding pattern 720-1 and the second light-shielding pattern 720-2 and the horizontal direction of the first adhesion surface 710-1 and / or the second adhesion surface 710-2, which is the same as the substantial inclination angle formed by the lamination of the light-shielding patterns due to a plurality of adhesion surfaces. Since it is realized by inclining at a predetermined angle θ in the vertical cross-section, the transmittance loss of external light in the inclined direction can be minimized.

[0106] Figure 5a FIG. shows the change of the maximum viewing angle θ2 of external light based on the degree of misalignment of the light-shielding pattern according to the diagonal projection length when the shortest straight-line distance h3 between the first adhesion surface and the second adhesion surface in the transmissivity variable optical laminate according to an embodiment of the present invention is the same.

[0107] Referring to Figure 5a, the maximum viewing angle θ2 of external light can be determined according to the degree of misalignment between the first light-shielding pattern 720-1 formed on the first adhesion surface 710-1 and the second light-shielding pattern 720-2 formed on the second adhesion surface 710-2. At this time, as the oblique projection length a increases, the maximum viewing angle θ2 of external light becomes larger. Therefore, in order to adjust the range of the maximum viewing angle θ2 of external light, it is preferable to adjust the oblique projection length a to a predetermined range. When the pattern sizes are the same, as the angle θ of the light-shielding pattern substantially inclined with respect to the adhesion surface decreases, the oblique projection length a becomes longer.

[0108] As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, in order to allow external light to reach the rear seat passenger of the driver's seat of the vehicle as an observer, the oblique projection length a can be 5 to 50% of the length ω1 of the first light-shielding pattern, but is not limited thereto. In this case, the transmittance of external light for the rear seat passenger of the driver's seat of the vehicle can be improved more effectively.

[0109] Figure 5b Shows the change in the maximum viewing angle θ2 of external light based on the shortest distance between the above-mentioned adhesion surfaces when the degree of misalignment of the light-shielding pattern of the variable transmittance optical laminate according to an embodiment of the present invention is the same according to the above oblique projection length.

[0110] Refer to Figure 5b , the angle of the maximum viewing angle θ2 of external light can be determined according to the shortest straight-line distance h3 between the above-mentioned first adhesion surface and the second adhesion surface. At this time, as the shortest straight-line distance h3 between the adhesion surfaces increases, the maximum viewing angle θ2 of external light becomes smaller. Therefore, in order to adjust the range of the maximum viewing angle θ2 of external light, it is preferable to adjust the shortest straight-line distance h3 between the adhesion surfaces to a predetermined range.

[0111] As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, in order to allow external light to reach the rear seat passenger of the driver's seat of the vehicle as an observer, for the height h2 of the second light-shielding pattern and the length ω1 of the first light-shielding pattern, the value of (h2 + h3) / ω1 can satisfy 0.5 to 4.0, but is not limited thereto. In this case, the transmittance of external light for the rear seat passenger of the driver's seat of the vehicle can be improved more effectively.

[0112] Figure 6a Shows the change in the maximum viewing angle θ1 of reflected light based on the degree of misalignment of the light-shielding pattern according to the oblique projection length when the shortest straight-line distance h3 between the above-mentioned first adhesion surface and the second adhesion surface of the variable transmittance optical laminate according to an embodiment of the present invention is the same.

[0113] Refer to Figure 6a, the maximum viewing angle θ1 of the reflected light can be determined according to the degree of misalignment between the first light-shielding pattern 720-1 formed on the first adhesion surface 710-1 and the second light-shielding pattern 720-2 formed on the second adhesion surface 710-2. At this time, as the oblique projection length a increases, the maximum viewing angle θ1 of the reflected light becomes larger. Therefore, in order to adjust the range of the maximum viewing angle θ1 of the reflected light, it is preferable to adjust the oblique projection length a to a predetermined range.

[0114] As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, in order for the reflected light to reach the rear seat passenger of the driver's seat of the vehicle who is the observer, the oblique projection length a can be 5 to 50% of the length ω1 of the first light-shielding pattern, but it is not limited thereto. In this case, the transmittance of the reflected light for the rear seat passenger of the driver's seat of the vehicle can be improved more effectively.

[0115] Figure 6b The degree of misalignment of the light-shielding pattern of the variable transmittance optical laminate according to the above oblique projection length in one embodiment of the present invention is shown, and the change in the maximum viewing angle θ1 of the reflected light based on the shortest distance between the above adhesion surfaces is shown.

[0116] Refer to Figure 6b , the angle of the maximum viewing angle θ1 of the reflected light can be determined according to the shortest straight-line distance h3 between the above first adhesion surface and the second adhesion surface. At this time, as the shortest straight-line distance h3 between the adhesion surfaces increases, the maximum viewing angle θ1 of the reflected light becomes smaller. Therefore, in order to adjust the range of the maximum viewing angle θ1 of the reflected light, it is preferable to adjust the shortest straight-line distance h3 between the adhesion surfaces to a predetermined range.

[0117] As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, in order for the reflected light to reach the rear seat passenger of the driver's seat of the vehicle who is the observer, for the height h2 of the second light-shielding pattern and the length ω1 of the first light-shielding pattern, the value of (h2 + h3) / ω1 can satisfy 0.5 to 4.0, but it is not limited thereto. In this case, the transmittance of the reflected light for the rear seat passenger of the driver's seat of the vehicle can be improved more effectively.

[0118] Refer to the example shown in Figure 7, when the length ω1 of the first light-shielding pattern of the variable transmittance optical laminate of the present invention is the same, the viewing angle range θ1 of the reflected image and the viewing angle range θ2 of external light can be adjusted according to the above pattern interval ω2, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adhesion surfaces, and / or the oblique projection length a. As an example, when the length ω1 of the first light-shielding pattern is the same, as the pattern interval ω2 decreases and / or as h2 and h3 increase, the maximum viewing angle θ1 of the reflected image becomes smaller. In addition, when the length ω1 of the first light-shielding pattern is the same, as the pattern interval ω2 decreases and / or as h2 and h3 of the light-shielding pattern increase, the maximum viewing angle θ2 of external light becomes smaller.

[0119] In addition, for the value obtained by adding the height h2 of the second light-shielding pattern and the shortest straight-line distance h3 between the adhesion surfaces and the length ω1 of the first light-shielding pattern, (h2 + h3) / ω1 can satisfy 0.5 to 4.0. For the pattern interval ω2 and the vertical light-transmitting portion ω3, based on the direction perpendicular to the plane, the aperture ratio p defined by ω3 / (ω2 + ω1)×100(%) can be 70% or more. At this time, the ranges of each value can be defined according to the relationship satisfying all of h2, h3, ω1, and p, and thus the pattern shape can be determined.

[0120] When the aperture ratio (p) in the top view direction of the shutter-type film 700 of the present invention is 70% or more, it has the advantages of being able to ensure the antireflection performance of the surface of the light control laminate while maintaining a high transmittance in the transmittance mode of the light control laminate. Generally speaking, if the aperture ratio (p) of the shutter-type film 700 is low, the transmittance deteriorates. However, in this application, since the light-shielding pattern is inclined at a predetermined angle with respect to the adhesion surface in the vertical cross-section, if the main user is located on the indoor side along the inclined direction, a relatively high transmittance can be achieved even when the aperture ratio is low.

[0121] In the present invention, as described above, if the maximum viewing angle θ1 of the reflected image and the maximum viewing angle θ2 of external light set according to the length ω1 of the first light-shielding pattern, the pattern interval ω2, the height h1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adhesion surfaces, and the oblique projection length a of the light-shielding pattern are considered together with the distance from the variable transmittance optical laminate of the present invention to the main user located on the indoor side and / or the line-of-sight height of the main user, the antireflection function and the external light transmittance function for any shape on the indoor side can be maximized more precisely.

[0122] Figure 8 It is a diagram showing an example of the above variable transmittance optical laminate. Referring to using the light control laminate of the present invention as a sunroof of a vehicle Figure 8The range that determines the visual field range of the passenger in the vehicle of the above main user is △D. Regarding the above △D, the distance to the end of the △D value range forms the maximum viewing angle of the external light, the distance from the point where the line of sight of the main user reaches to the ceiling is D2, the distance to the start of the △D value range forms the maximum viewing angle of the reflected light, and the distance from the point where the line of sight of the main user reaches to the ceiling is D1.

[0123] In an example of the present invention, when the maximum viewing angle θ1 of the reflected image and the maximum viewing angle θ2 of the external light are set such that the line of sight position of the main user on the indoor side of the variable transmittance optical laminate of the present invention deviates from the maximum viewing angle θ1 of the reflected image but is within the range of the maximum viewing angle θ2 of the external light, the antireflection function and the external light transmission function for any shape on the indoor side can be maximized. Therefore, the maximum viewing angle θ1 of the reflected image and the maximum viewing angle θ2 of the external light of the present invention can be set such that the line of sight position of the main user on the indoor side of the variable transmittance optical laminate of the present invention deviates from the maximum viewing angle θ1 of the reflected image but is within the range of the maximum viewing angle θ2 of the external light, and the length ω1 of the first light-shielding pattern, the pattern interval ω2, the height h1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adhesion surfaces, and / or the oblique projection length a of the light-shielding pattern of the louvered film of the present invention can be set in such a way as to achieve such a viewing angle range.

[0124] More specifically, for the variable transmittance optical laminate formed with an arbitrary light-shielding pattern, the light starting from the front seat panel of the vehicle forms the maximum viewing angle θ1 of the reflected image and reaches the visual field of the passenger, and the external light forms the maximum viewing angle θ2 of the external light and reaches the visual field of the passenger.

[0125] As an example of the present invention, the range of the maximum viewing angle θ1 of the reflected image can be 40° to 75°, and the viewing angle of the above reflected image is the angle of the reflected image with respect to the straight line perpendicular to the adhesion surface on the indoor side in the vertical cross-section of the variable transmittance optical laminate.

[0126] As an example of the present invention, the range of the maximum viewing angle θ2 of the external light transmitted from the outside can be 60° to 85°, and the viewing angle of the above external light is the angle of the external light with respect to the straight line perpendicular to the adhesion surface on the indoor side in the vertical cross-section of the variable transmittance optical laminate.

[0127] In an example of the present invention, when the dimming laminate of the present invention is used as a sunroof of a vehicle, in order not to cause glare to the visual field of the rear seat passenger due to the indoor side reflected image of the front seat panel or the like, and at the same time not to reduce the transmittance of the external light, the range where the visual field of the rear seat passenger is located must be adjusted to the extent that it includes the viewing angle range θ2 of the external light but does not include the viewing angle range θ1 of the reflected image.

[0128] The appropriate range of the curvature of the variable transmittance optical laminate applied in the above vehicle can be changed according to the height of the vehicle body, the sitting height of the passengers, etc., but may be affected by the ceiling height. The above ceiling height refers to the vertical distance from the eye height of the rear seat passenger to the outermost surface on the indoor side of the ceiling, and specifically can satisfy 300 mm to 600 mm, preferably can satisfy 300 mm to 500 mm.

[0129] Hereinafter, with reference to Figure 8 to more specifically describe the height h1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adhesion surfaces, and the oblique projection length a that do not cause glare to the field of view of the rear seat passenger for the reflected image of the front seat panel while not reducing the transmittance of external light.

[0130] Figure 8 It is a diagram showing the reflected image (dashed arrow) starting from the front seat panel and reaching the field of view of the passenger and the external light (solid arrow) passing through from the outside and reaching the field of view of the passenger. For example, when the pattern pitch without a light-shielding pattern formed on the adhesion surface is set to ω2, the straight-line distance from the point where the light starting from the front seat panel reaches the variable transmittance optical laminate to the ceiling of the rear seat passenger is set to L', the distance from the point where the external light reaches the field of view of the rear seat passenger to the ceiling of the rear seat passenger is set to D2, and the distance from the point where the reflected light reaches the field of view of the rear seat passenger to the ceiling of the rear seat passenger is set to D1, the value of D1 - D2 means △D. The above △D value is the field of view range of the rear seat passenger that does not cause glare to the field of view of the rear seat passenger for the reflected image of the front seat panel while not reducing the transmittance of external light. Therefore, the field of view of the rear seat passenger can be within the range of △D.

[0131] The △D value is the field of view range of the subject that does not cause glare to the reflected image in the field of view of the subject while not reducing the transmittance of external light. Specifically, if the position of the eye is within the range of △D, the reflected light will not be seen and only the external light will be seen. If it deviates from the range of △D, not only the external light will be seen, but also the reflected light will be seen. As an example, if it is assumed that the variable transmittance optical laminate of the present invention is applied to the sunroof of a vehicle, it is preferable that the vertical distance from the eye height of the rear seat passenger to the outermost surface on the indoor side of the ceiling (variable transmittance optical laminate), that is, the range of 300 mm to 500 mm, overlaps with the range of the △D value.

[0132] The above-mentioned △D value can be determined based on the length ω1 of the first light-shielding pattern of the light-shielding pattern, the pattern interval ω2, the height h1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adhesion surfaces, and the oblique projection length a. Specifically, since the viewing angle of the reflected image is tan^(-1)(ω2 / (2h2 + 2h3)), the viewing angle of the external light is tan^(-1)((ω2 + a) / (h2 + h3)), the distance D1 from the point where the reflected light reaches the field of view of the rear-seat passenger to the ceiling of the rear-seat passenger is L' / tan(θ1), and the distance D2 from the point where the external light reaches the field of view of the rear-seat passenger to the ceiling of the rear-seat passenger is (L' + ω2 / 2 + a) / tan(θ2). Therefore, the viewing angles θ1 and θ2 are adjusted by the sum of the length ω1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, and the shortest straight-line distance h3 between the adhesion surfaces, and the values of D1 and D2 are adjusted according to the above values of θ1, θ2, the pattern interval ω2, and the oblique projection length a, thereby determining the △D range value.

[0133] In addition, the larger the value of θ2, the smaller the value of θ1, and the larger the range of △D. Preferably, D2 can be 500 mm or less, and D2 + △D can be 300 mm or more.

[0134] At this time, if the above-mentioned oblique projection length a increases, it will cause a loss of the aperture ratio. However, as the value of θ1 decreases, the end point of △D moves away from the upper transmissivity variable optical laminate, so the range of △D will become wider.

[0135] In an example of the present invention, the above-mentioned louvered film 700 includes a light-shielding pattern 720. The above-mentioned light-shielding pattern 720 can be directly formed on the light-adjusting laminate. In addition, it can also be formed on a separate transparent film and attached to the light-adjusting laminate. When the above-mentioned light-shielding pattern 720 is formed on the transparent film, an adhesive layer (not shown for convenience) can also be further included between the above-mentioned transparent film and the light-adjusting laminate. As an example, a structure in which a first light-shielding pattern directly formed on the light-adjusting laminate, an adhesive / bonding agent layer formed on the above-mentioned first light-shielding pattern, and a transparent film layer on which a second light-shielding pattern is formed are laminated can be included.

[0136] The above-mentioned transparent film can be a film developed in the past or in the future. The material of the above-mentioned transparent film layer used in the manufacturing of the louver film 700 in the present invention can be any known synthetic resin or natural resin that exhibits a predetermined light transmittance when formed into a film. Considering economy and processability, a synthetic resin is preferred. As examples of resins that can be used as the material of the above-mentioned transparent film layer, polyvinyl chloride (PVC), polyethylene terephthalate (PET), polyacrylate, polymethyl methacrylate, polyurethane, polycarbonate, polyethylene, polypropylene, cellulose acetate butyrate (CAB), or copolymers thereof are preferred.

[0137] The above-mentioned louver film 700 may include a light-shielding pattern 720, and an adhesive layer (not shown for convenience) may be further included between the adhesion surface and the light-shielding pattern.

[0138] The above-mentioned adhesive layer (not shown for convenience) can be formed using an adhesive, and preferably has excellent heat-resistant adhesiveness. The above-mentioned heat-resistant adhesiveness means that the adhesion change rate after being placed in an 80°C oven for 240 hours is 30% or less or no bubbles are generated compared to the adhesion before being put into the oven.

[0139] The above-mentioned adhesive can be an adhesive developed in the past or in the future. 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, etc. can be used. The above-mentioned adhesive is not particularly limited as long as it has adhesiveness and viscoelasticity. Considering ease of acquisition and other aspects, an acrylic adhesive is preferably used. For example, it may include a (meth)acrylate copolymer, a cross-linking agent, and a solvent, etc. In addition, it can also be selected considering the adhesion characteristics to the light-shielding pattern 720 and ensuring viscoelasticity. For example, the adhesive / bonding layer may include an acrylate-based pressure-sensitive adhesive / bonding (PSA) substance or an optically clear adhesive / bonding (OCR) substance.

[0140] The above-mentioned light-shielding pattern 720 can be applied without limitation to materials used for light-shielding purposes. For example, it can be manufactured by including a light-shielding agent, a light diffusing agent, and / or a coloring agent. In one embodiment of the present invention, the light-shielding pattern of the present invention can be manufactured using a composition containing a black pigment, and a composition containing a black pigment dispersion and / or a black dye can be used as the main constituent, and further includes a resin, a polymerization initiator, and additional additives as needed.

[0141] The method for forming the light-shielding pattern 720 on the above-mentioned adhesion surface 710 is not particularly limited. As an example, the following methods can be applied: a method of forming a groove on a transparent film and filling a material for forming the above-mentioned light-shielding pattern 720; or a method of manufacturing a photosensitive resin composition for forming the above-mentioned light-shielding pattern 720 and forming the light-shielding pattern 720 on the above-mentioned transparent film by a photolithography method.

[0142] The above-mentioned adhesion surface 710 can be one side of the indoor side of the light-adjusting laminate of the present invention, or can be a separate additional transparent film outside the light-adjusting laminate, but is not limited thereto.

[0143] Light-adjusting laminate 100

[0144] The light-adjusting laminate of the present invention is characterized in that it includes an electric field-driven liquid crystal between polarizing plates, and particularly has a structure in which a transparent conductive layer is in direct contact with a polarizing plate. Therefore, not only can the thickness of the light-adjusting laminate and the transmissivity variable optical laminate including the same be reduced, providing advantages in terms of manufacturing processes and applications, but in particular, the viewing angle adjustment characteristics and transmissivity adjustment characteristics of the reflected image, which are the main objects of the present invention, can be maximized.

[0145] Specifically, the light-adjusting laminate of the present invention includes a light-adjusting laminate having a first polarizing plate, a first transparent conductive layer formed on one surface of the first polarizing plate, a second polarizing plate opposite to the first polarizing plate, a second transparent conductive layer formed on one surface of the second polarizing plate and opposite to the first transparent conductive layer, and a liquid crystal layer disposed between the first transparent conductive layer and the second transparent conductive 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.

[0146] FIG. 9 is a diagram showing the laminated structure of the polarizing plate according to one or more embodiments of the present invention.

[0147] Referring to FIG. 9, the above-mentioned polarizing plate 200 includes a polarizer 210, and functional layers such as a protective layer 220, a retardation adjustment layer 230, and a refractive index adjustment layer 240 may also be included on one or both surfaces of the polarizer 210. For example, the polarizing plate 200 may include a polarizer 210 and a protective layer 220 laminated on one or both surfaces of the polarizer 210 (refer to Figure 9a and Figure 9b ), and may include a polarizer 210, a protective layer 220 laminated on one surface of the polarizer 210, and a retardation adjustment layer 230 laminated on the other surface of the polarizer 210 opposite to the above-mentioned one surface (refer to Figure 9c) may include a polarizer 210, a protective layer 220 laminated on one side of the polarizer, and a retardation adjustment layer 230 and a refractive index adjustment layer 240 laminated in sequence on the other side of the polarizer 210 opposite to the one side (refer to Figure 9d ) may include a polarizer 210, a protective layer 220 laminated on one side of the polarizer, and a protective layer 220 and a retardation adjustment layer 230 laminated in sequence on the other side of the polarizer 210 opposite to the one side (refer to Figure 9e ).

[0148] The above-mentioned polarizer 210 may use a polarizer developed in the past or in the future. For example, a stretched polarizer or a coated polarizer, etc. may be used.

[0149] In one embodiment, the above-mentioned stretched polarizer may include a stretched polyvinyl alcohol (PVA) - based resin. The above-mentioned polyvinyl alcohol (PVA) - based resin may be a polyvinyl alcohol - based resin obtained by saponifying a polyvinyl acetate - based resin. As the polyvinyl acetate - based resin, in addition to polyvinyl acetate which is a homopolymer of vinyl acetate, copolymers of vinyl acetate and other monomers capable of copolymerizing with it, etc. may also be cited. As the above-mentioned other monomers, they may be unsaturated carboxylic acid - based, unsaturated sulfonic acid - based, olefin - based, vinyl ether - based, acrylamide - based monomers having an ammonium group, etc. In addition, the polyvinyl alcohol (PVA) - based resin includes modified substances. For example, it may also be polyvinyl formal or polyvinyl acetal modified by aldehydes.

[0150] In one embodiment, the above-mentioned coated polarizer may be formed using a liquid crystal coating composition. At this time, the above-mentioned liquid crystal coating composition may include a reactive liquid crystal compound, a dichroic dye, etc.

[0151] The above-mentioned reactive liquid crystal compound may refer to a compound that includes a mesogen skeleton, etc. and includes one or more polymerizable functional groups. Such a reactive liquid crystal compound has been widely known under the name of so-called reactive mesogen (RM). The above-mentioned reactive liquid crystal compound can be polymerized by means of light or heat to form a cured film in which a polymer network is formed while maintaining the liquid crystal alignment.

[0152] The above-mentioned reactive liquid crystal compound may be a monofunctional or polyfunctional reactive liquid crystal compound. The above-mentioned monofunctional reactive liquid crystal compound may refer to a compound having 1 polymerizable functional group, and the polyfunctional reactive liquid crystal compound may refer to a compound containing 2 or more polymerizable functional groups.

[0153] The above-mentioned dichroic dye is a component added to the liquid crystal coating composition to impart polarization characteristics, and has the property that the absorbance in the long axis direction of the molecule is different from the absorbance in the short axis direction. The above-mentioned dichroic dye can be a dichroic dye developed in the past or in the future. For example, it can include one or more selected from the group consisting of azo dyes, anthraquinone dyes, perylene dyes, merocyanine dyes, azomethine dyes, phthaloperylene dyes, indigo dyes, dioxadine dyes, polythiophene dyes, and phenoxazine dyes.

[0154] The above-mentioned liquid crystal coating composition may further contain a solvent capable of dissolving the above-mentioned reactive liquid crystal compound and the above-mentioned dichroic dye. For example, propylene glycol monomethyl ether acetate (PGMEA), methyl ethyl ketone (MEK), xylene, chloroform, etc. can be used. In addition, the above-mentioned liquid crystal coating composition may also contain a leveling agent, a polymerization initiator, etc. within the range that does not hinder the polarization characteristics of the coating film.

[0155] The above-mentioned protective layer 220 is intended to protect the polarization characteristics of the polarizer 210 from the influence of subsequent processes and the external environment, and can be realized in the form of a protective film or the like.

[0156] As Figure 9a and Figure 9b As shown in the figure, the above-mentioned protective layer 220 can be formed by directly contacting one or both sides of the polarizer 210, but it is not limited thereto. For example, the above-mentioned protective layer can also be used in a multilayer structure formed by continuously laminating one or more protective layers, and can be formed by directly contacting other functional layers.

[0157] In one or more embodiments, the above-described protective layer 220 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).

[0158] As Figure 9c and Figure 9d illustrated, the above-described retardation adjusting layer 230 may be formed in direct contact with one surface of the polarizer 210, but is not limited thereto. For example, as Figure 9e illustrated, the above-described retardation adjusting layer 230 may be formed on one surface of the protective layer 220 so as to laminate the polarizer 210, the protective layer 220, and the retardation adjusting layer 230 in this order.

[0159] The above-described retardation adjusting layer 230 may use a polymer stretched film or a liquid crystal polymer film obtained by stretching a polymer film capable of imparting optical anisotropy in an appropriate manner by stretching.

[0160] In one embodiment, the above-mentioned polymer stretched film may use a polymer layer containing the following substances: polyolefins such as polyethylene (PE) or polypropylene (PP), cyclic olefin polymers (COP) such as polynorbornene, polyvinyl chloride (PVC), polyacrylonitrile (PAN), polysulfone (PSU), acryl resin, polycarbonate (PC), polyesters such as polyethylene terephthalate (PET), polyacrylate, cellulose ester polymers such as polyvinyl alcohol (PVA) or triacetyl cellulose (TAC), or copolymers of two or more of the monomers forming the above polymers, etc.

[0161] The method for obtaining the above-mentioned polymer stretched film is not particularly limited. For example, it can be obtained by stretching after forming the above-mentioned polymer material into a film shape. The method for forming into a film shape is not particularly limited, and it 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, casting molding, etc., or it can also use secondary processing molding methods such as compression molding and vacuum molding. Among them, extrusion molding and casting molding are preferably used. At this time, for example, an extruder equipped with a T-die, a circular die, etc. can be used to extrude and mold the unstretched film. In the case of 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 it can also be molded via melt-kneading during extrusion molding. In addition, a solvent common to various resin components, such as chloroform, dichloromethane, etc., can be used to dissolve various resin components, and then cast, dried, and cured to thereby perform casting molding on the unstretched film.

[0162] For the above-mentioned polymer stretched film, the molded film can be uniaxially stretched in the machine direction (MD; Mechanical Direction, longitudinal or length direction), uniaxially stretched in the direction perpendicular to the machine direction (TD; Transverse Direction, transverse or width direction). In addition, a biaxially stretched film can also be manufactured by stretching through a sequential biaxial stretching method of roll stretching and tenter stretching, a simultaneous biaxial stretching method based on tenter stretching, a biaxial stretching method based on tubular stretching, etc.

[0163] The above liquid crystal polymer film may contain a reactive liquid crystal compound in a polymerized state. The above reactive liquid crystal compound may equally apply to the content of the reactive liquid crystal compound for the above coating type polarizer.

[0164] In one or more embodiments, for the thickness of the above retardation adjustment layer 230, in the case of a polymer stretched film, it may be 10 μm to 100 μm, and in the case of a liquid crystal polymer film, it may be 0.1 μm to 5 μm.

[0165] The above refractive index adjustment layer 240 is provided to compensate for the refractive index difference of the optical laminate caused by the above transparent conductive layer 300, and can play a role in improving visible characteristics and the like by reducing the refractive index difference. In addition, the above refractive index adjustment layer 240 may also be provided to correct the color caused by the above transparent conductive layer 300. On the other hand, in the case where the above transparent conductive layer has a pattern, through the above refractive index adjustment layer 240, it is possible to compensate for the transmittance difference between the patterned pattern region and the non-patterned region where no pattern is formed.

[0166] Specifically, the above transparent conductive layer 300 is adjacent and laminated to other members (such as a polarizer, etc.) having a different refractive index from it. Due to the refractive index difference with the adjacent other layers, a difference in light transmittance will be induced. Especially in the case where the transparent conductive layer has a pattern, there may be a problem that the pattern region and the non-pattern region look different. Therefore, by including the above refractive index adjustment layer 240, it is possible to compensate for the refractive index and reduce the difference in light transmittance of the optical laminate. Especially in the case where the transparent conductive layer has a pattern, the pattern region and the non-pattern region will not look different.

[0167] In one embodiment, the refractive index of the above refractive index adjustment layer 240 may be appropriately selected according to the material of the adjacent other members, preferably it may be 1.4 to 2.6, and more preferably it may be 1.4 to 2.4. In this case, it is possible to prevent light loss caused by a significant refractive index difference between the above polarizer 210 and other members and the transparent conductive layer 300.

[0168] The above refractive index adjustment layer 240 has no particular limitation as long as it can prevent a significant refractive index difference between the polarizer 210 and other members and the transparent conductive layer 300. Compounds used to form a refractive index adjustment layer in the past or developed in the future may be used. For example, it may be formed from a refractive index adjustment layer forming composition containing a polymerizable isocyanurate compound.

[0169] In one embodiment, in addition to the above functional layers, the polarizing plate 200 may further include other functional layers to assist or enhance the characteristics of the polarizer. For example, in order to further improve the mechanical durability, an overcoat or a hard coating layer may also be included.

[0170] In one or more embodiments, the polarizing plate 200 may have a thickness of 30 μm to 200 μm, preferably 30 μm to 170 μm, and more preferably 50 μm to 150 μm. In this case, a thin optical laminate can be manufactured while maintaining the optical properties of the polarizing plate 200 .

[0171] The transparent conductive layer 300 is provided for driving the liquid crystal layer 400 and can be formed in direct contact with the polarizing plate 200. For example, as shown in FIG1 , the first transparent conductive layer 300-1 and the second transparent conductive layer 300-2 can be formed in direct contact with the first polarizing plate 200-1 and the second polarizing plate 200-2, respectively.

[0172] In the past, the dimming stack used to manufacture smart windows and the like was manufactured by forming a conductive layer for liquid crystal driving on one side of a substrate and bonding the other side of the substrate to a polarizing plate. However, the dimming stack 100 of the present invention is characterized in that a conductive layer is directly formed on one side of a polarizing plate without including a separate substrate for forming a conductive layer, thereby reducing the thickness of the stack and improving the transmittance and bending characteristics in the light transmission mode. Furthermore, the dimming stack 100 of the present invention forms a conductive layer directly on one side of a polarizing plate, so that even if a louver-type film 700 is further included on the indoor side of the dimming stack for the anti-reflection function of the reflected image, the thickness of the variable transmittance optical stack of the present invention can be reduced and the anti-reflection function can be imparted without reducing the transmittance adjustment function.

[0173] In one embodiment, the transparent conductive layer 300 may be formed by direct evaporation on one side of the polarizing plate 200. In this case, in order to improve the adhesion between the transparent conductive layer 300 and the polarizing plate 200, the transparent conductive layer 300 may be formed by directly contacting the pretreated surface of the polarizing plate 200 after pretreatment such as corona treatment or plasma treatment is performed on one side of the polarizing plate 200. The pretreatment is not limited to corona treatment or plasma treatment, and a pretreatment process previously or developed in the future may be used within the scope that does not impair the purpose of the present invention.

[0174] In another embodiment, in order to improve the adhesive force with the polarizing plate 200 , the transparent conductive layer 300 may be formed in direct contact with the polarizing plate 200 via an easy-adhesive layer (not shown) on one side of the polarizing plate 200 .

[0175] The transmittance of the above-mentioned transparent conductive layer 300 with respect to visible light is preferably 50% or more. For example, it may include one or more selected from the group consisting of transparent conductive oxides, metals, carbon-based materials, conductive polymers, conductive inks, and nanowires, but is not limited thereto, and materials of transparent conductive layers developed in the past or in the future can be used.

[0176] In one or more embodiments, the above-mentioned transparent conductive oxide may include one or more selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (IZTO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), fluorine tin oxide (FTO), and zinc oxide (ZnO), etc. In addition, the above-mentioned 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 them, for example, it may include a silver-palladium-copper (APC) alloy or a copper-calcium (CuCa) alloy. The above-mentioned carbon-based material may include one or more selected from the group consisting of carbon nanotubes (CNT) and graphene, etc., and the above-mentioned conductive polymer may include one or more selected from the group consisting of polypyrrole, polythiophene, polyacetylene, poly(3,4-ethylenedioxythiophene) (PEDOT), and polyaniline, etc. The above-mentioned conductive ink may be an ink obtained by mixing metal powder and a curable polymer binder, and the nanowire may be, for example, a silver nanowire (AgNW).

[0177] In addition, the above-mentioned transparent conductive layer 300 may be formed in a structure of two or more layers by combining the above-mentioned substances. For example, in order to reduce the reflectivity of incident light and improve the transmittance, it may be formed of a two-layer structure including a metal layer and a transparent conductive oxide layer.

[0178] The above-mentioned liquid crystal layer 400 can adjust the transmittance of light incident from one or more directions according to an electric field, thereby changing the driving mode of the above-mentioned optical laminate.

[0179] The above-mentioned liquid crystal layer 400 may include a liquid crystal compound and a spacer. For example, as Figure 1b shown in the figure, it may refer to the region defined by the first alignment film 500-1, the second alignment film 500-2, and the sealant 600.

[0180] The above liquid crystal compound is not particularly limited as long as it can be driven according to an electric field and can control the light transmittance. Liquid crystal compounds developed in the past or in the future can be used. For example, the content of the reactive liquid crystal compound regarding the above coating type polarizer can be similarly applied.

[0181] There is no particular limitation on the liquid crystal behavior mode of the above liquid crystal layer 400. For example, as Figure 1b shown in the figure, it can be driven by the twisted nematic (TN) mode. In addition to this, it can also be driven by the super twisted nematic (STN) mode, the vertical alignment (VA) mode, the electrically controlled birefringence (ECB) mode, etc.

[0182] The above spacer can include at least one of a ball spacer and a column spacer, and a ball spacer is particularly preferred. The above spacer can be one or more, and the height is preferably 1 μm to 10 μm. In addition, when observed from the top view direction, considering the improvement of the user's visibility and the transmittance in the light transmission mode, the area occupied by the above spacer in the liquid crystal layer 400 is preferably 0.01 to 10% of the area of the liquid crystal layer 400.

[0183] In one embodiment, the above liquid crystal layer 400 may further include an alignment film 500 as needed. For example, it can be formed on both surfaces of the liquid crystal layer 400 containing a liquid crystal compound.

[0184] The above alignment film 500 is not particularly limited as long as it is used to impart an orientation to the liquid crystal compound, and preferably may include a photo-orientable or photocurable polymer, etc. For example, the above alignment film 500 can be produced by coating an alignment film coating composition containing a photo-orientable or photocurable polymer, a photoinitiator, and a solvent and then curing it.

[0185] The above-mentioned photo-orientable or photo-curable polymer is not particularly limited, and cinnamate-based polymers, polyimide-based polymers, etc. can be used. For example, poly(vinyl cinnamate) (PVCi), poly(siloxane cinnamate) (PSCN), poly(ω(4-chalconyloxy)alkoxyphenyl maleimide), 6-FDA-HAB-Cl, etc. can be used, and polymers that can exhibit orientation developed in the past or in the future can be used.

[0186] The above-mentioned sealant 600 is located between the first polarizing plate 200-1 and the second polarizing plate 200-2 in the non-active region, and functions to bond the first polarizing plate and the second polarizing plate. It can be provided together with spacers between the first polarizing plate 200-1 and the second polarizing plate 200-2 to ensure a space for the liquid crystal layer 400.

[0187] The above-mentioned sealant 600 may contain a curable resin as a base resin. As the above-mentioned base resin, an ultraviolet curable resin or a thermosetting resin known in the art to be usable for sealants can be used. The above-mentioned ultraviolet curable resin can be a polymer of an ultraviolet curable monomer. The above-mentioned thermosetting resin can be a polymer of a thermosetting monomer.

[0188] As the base resin of the above-mentioned sealant 600, for example, acrylate-based resins, epoxy-based resins, urethane-based resins, phenol-based resins, or mixtures of the above resins can be used. In one embodiment, the above-mentioned base resin can be an acrylate-based resin, and the above-mentioned acrylate-based resin can be a polymer of an acrylic monomer. The above-mentioned acrylic monomer can be, for example, a polyfunctional acrylate. In another embodiment, the above-mentioned sealant may further contain a monomer component in the base resin. The above-mentioned monomer component can be, for example, a monofunctional acrylate. In this specification, a monofunctional acrylate can refer to a compound having 1 acryloyl group, and a polyfunctional acrylate can refer to a compound having 2 or more acryloyl groups. The above-mentioned curable resin can be cured by irradiating ultraviolet rays and / or heating. Regarding the above-mentioned ultraviolet irradiation conditions or heating conditions, they can be appropriately implemented within the range that does not damage the purpose of this application. The above-mentioned sealant may also contain an initiator as needed, such as a photoinitiator or a thermal initiator.

[0189] The above-mentioned sealant 600 can be formed by a method commonly used in the art. For example, the sealant can be applied to the periphery (i.e., the non-active region) of the above-mentioned liquid crystal layer using a dispenser equipped with a nozzle to form it.

[0190] <Smart Windows and Sunroofs>

[0191] In addition to the above-described variable transmittance optical laminate, the present invention further includes a smart window including the above-described variable transmittance optical laminate. Further, the present invention includes an automobile in which the above-described smart window is applied to at least one of a front window, a rear window, a side window, a sunroof, and an interior partition, and a building window including the above-described smart window.

[0192] For example, in an automobile including the smart window of the present invention, vehicle glass may be bonded to both surfaces of the variable transmittance optical laminate, and the above-described vehicle glass may include the above-described louvered film. For example, the smart window including the above-described vehicle glass can be manufactured by placing an adhesive film and vehicle glass on both surfaces of the optical laminate and then heating for 10 to 20 minutes in a vacuum state at a temperature of 90 ° C and about 1 bar (bar) using a press machine. The above-described adhesive film may include an EVA film, a PVB film, or the like.

Claims

1. A variable transmittance optical stack, comprising: A light-adjusting laminate including electric field driven liquid crystals between polarizing plates; and a louver-type film disposed on at least a portion of the indoor side of the dimming stack, The louvered film is stacked with two or more layers and includes a light-shielding pattern. The light shielding pattern is arranged to face the indoor side.

2. The variable transmittance optical stack according to claim 1, wherein the louver film comprises a second adhesive surface located on the indoor side and a first adhesive surface located between the second adhesive surface and the dimming stack. The light shielding pattern of the second adhesive surface protrudes toward the indoor side.

3. The variable transmittance optical laminate according to claim 2, The first adhesive surface includes a first light shielding pattern, The second adhesive surface includes a second light shielding pattern, In the vertical section, the straight line connecting the outermost point where the first shading pattern meets the first adhesive surface and the outermost point where the corresponding second shading pattern meets the second adhesive surface is an oblique line relative to the first adhesive surface and forms a predetermined inclination angle θ with the adhesive surface.

4. According to the variable transmittance optical stack according to claim 3, in a vertical cross-section, the length a of the oblique line connecting the outermost point where the first shading pattern meets the first adhesive surface and the outermost point of the corresponding second shading pattern projected onto the first adhesive surface is 5 to 50% of the length ω1 of the first shading pattern.

5. According to the variable transmittance optical stack according to claim 1, the maximum viewing angle θ1 of the reflected image of the variable transmittance optical stack is in the range of 40° to 75°, and the viewing angle of the reflected image is the angle of the reflected image relative to the straight line perpendicular to the adhesive surface on the indoor side in the vertical cross-section of the variable transmittance optical stack.

6. According to the variable transmittance optical stack according to claim 1, the maximum viewing angle θ2 of external light passing through the variable transmittance optical stack from the outside is in the range of 60° to 85°, and the viewing angle of the external light is the angle of the external light relative to the straight line perpendicular to the adhesive surface on the indoor side in the vertical cross-section of the variable transmittance optical stack. 7 . The variable transmittance optical laminate according to claim 1 , wherein the louver film is formed by bonding at least two adhesive surfaces via an adhesive / adhesive.

8. The variable transmittance optical laminate according to claim 1, wherein the louver film includes a pattern interval ω2 where the light shielding pattern is not formed on an adhesive surface, and a light shielding portion where the light shielding pattern is formed on an adhesive surface, When the height of the second shading pattern is set to h2, the shortest straight-line distance between the adhesion surfaces is set to h3, and the length of the first shading pattern is set to ω1, the value of (h2+h3) / ω1 is 0.5~4.0, and the opening ratio p defined by ω3 / (ω2+ω1)×100(%) based on the direction perpendicular to the plane is greater than 70%.

9. The variable transmittance optical laminate according to claim 1, The dimming stack comprises: a first polarizing plate; A first transparent conductive layer formed on one surface of the first polarizing plate; a second polarizing plate, which is opposite to the first polarizing plate; A second transparent conductive layer formed on one side of the second polarizing plate and opposite to the first transparent conductive layer; as well as a liquid crystal layer disposed between the first transparent conductive layer and the second transparent conductive layer, At least one of the first transparent conductive layer and the second transparent conductive layer is formed to be in direct contact with one of the first polarizing plate and the second polarizing plate.

10. The variable transmittance optical stack according to claim 9, wherein at least one of the first transparent conductive layer and the second transparent conductive layer comprises one or more selected from the group consisting of transparent conductive oxides, metals, carbon-based materials, conductive polymers, conductive inks, and nanowires. 11 . The variable transmittance optical laminate according to claim 9 , wherein at least one of the first polarizing plate and the second polarizing plate comprises one or more functional layers selected from the group consisting of a protective layer, a phase difference adjusting layer, and a refractive index adjusting layer. 12 . The variable transmittance optical laminate according to claim 9 , wherein at least one of the first polarizing plate and the second polarizing plate has a thickness of 30 μm to 200 μm. 13 . The variable transmittance optical stack according to claim 9 , wherein the liquid crystal layer includes one or more spacers selected from the group consisting of spherical spacers and columnar spacers. 14 . The variable transmittance optical laminate according to claim 9 , further comprising alignment films on both surfaces of the liquid crystal layer. 15 . A skylight comprising the variable transmittance optical laminate according to claim 1 .

Images