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 including a light-shielding pattern, and the light-shielding pattern protruding toward 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 including a light shielding pattern protruding toward the indoor side.

Description

Technical Field

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

[0002] Generally speaking, glass windows of mobile tools such as vehicles are often coated with external light blocking coatings. However, the transmittance of glass windows of conventional mobile tools is fixed, and the transmittance of external light blocking coatings is also fixed. Therefore, since the overall transmittance of the windows of such conventional mobile tools is fixed, accidents may occur. For example, if the overall transmittance is set low, there will be no problem during the day when the surrounding light is sufficient. However, in situations such as the night when the surrounding light is insufficient, there is a problem that it is difficult for the driver and the like to correctly view the surrounding conditions of the mobile tool. In addition, if the overall transmittance is set high, there is a problem that it may cause dazzle to the driver and the like during the day when the surrounding light is sufficient. For this reason, a variable transmittance optical laminate that can change the transmittance of light when a voltage is applied has been developed.

[0003] On the other hand, in a society that values ​​privacy protection, attempts have been made to give glass windows an anti-reflection function. In particular, in the case of a sunroof of a vehicle, there is a problem that the reflected image of the front seat panel reflected from the sunroof during night driving causes glare to the rear seat passengers. Therefore, when a variable transmittance optical laminate is applied to a sunroof, etc., not only a transmittance adjustment function is required, but also an improvement in the anti-reflection function during night driving, etc. is required.

[0004] For this reason, a technology for attaching a coating having an anti-reflection function on 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 anti-reflection coating, specifically a window glass including two or more layers of materials having high and low refractive indices.

[0005] However, when a multilayer coating layer is introduced to impart an anti-reflection function, the thickness of the optical laminate becomes thicker, the transmittance adjustment performance decreases, or the manufacturing process becomes complicated. In addition, when such a coating is applied 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, the overall thickness of the laminate becomes too thick, making it unsuitable for use in vehicles or buildings.

[0006] Therefore, the actual situation is that it is necessary to develop an optical layered body and a skylight including the same which have an antireflection function without reducing the transmittance of external light and are thin and advantageous in bending characteristics.

[0007] Prior art literature

[0008] Patent Literature

[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, has a thin 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 the shutter film includes a light-shielding pattern protruding toward the indoor side.

[0014] 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 45° to 75°, and the viewing angle of the reflected image is an angle of the reflected image with respect to a straight line perpendicular to the adhesion surface on the indoor side in a vertical cross-section of the variable transmittance optical laminate.

[0015] In one embodiment of the present invention, the range of the maximum viewing angle θ2 of the external light transmitted from the outside of the variable transmittance optical laminate may be 60° to 85°, and the viewing angle of the external light is an angle of the external light with respect to a straight line perpendicular to the adhesion surface on the indoor side in a vertical cross-section of the variable transmittance optical laminate.

[0016] The shutter film may include a light-transmitting portion where the light-shielding pattern is not formed and a light-shielding portion where the light-shielding pattern is formed. When the height of the light-shielding pattern is h and the light-shielding portion is ω1, h / ω1 may be 0.5 to 3.0. When the light-transmitting portion is ω2, the aperture ratio p defined by ω2 / (ω2 + ω1) × 100 (%) may be 70% or more.

[0017] 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 disposed between the first transparent conductive layer and the second transparent conductive layer, wherein at least one of the first transparent conductive layer and the second transparent conductive layer may be formed to be in direct contact with one of the first polarizing plate and the second polarizing plate.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] In another embodiment of the present invention, alignment films may also be included on both surfaces of the liquid crystal layer.

[0023] The present invention provides a sunroof including the above-described variable transmittance optical laminate.

[0024] Advantages of the Invention

[0025] According to an embodiment of the present invention, the optical laminate includes a shutter-type film having a light-shielding pattern protruding toward the interior side, thereby exhibiting an excellent antireflection function without reducing the transmittance of external light.

[0026] According to an embodiment of the present invention, in the optical laminate, since the transparent conductive layer is directly formed on the polarizing plate itself to enable a form of direct contact therewith, rather than the transparent conductive layer being formed on a separate substrate and attached to the polarizing plate, an optical laminate having a thin overall thickness and favorable bending characteristics can be provided.

[0027] 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, there is an advantage that the antireflection function and the transmittance adjustment function can be maximized.

[0028] Furthermore, in the case of using the variable transmittance optical laminate of the present invention as a sunroof, it is possible to improve the phenomenon of glare caused by the reflection image of the front seat panel reflected from the sunroof to the field of view of the rear seat passengers during night driving. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1a and Figure 1b is a diagram showing the laminated structure of a variable transmittance optical laminate according to an embodiment of the present invention.

[0030] Figure 2 is a diagram showing the structure of a louvered film according to an embodiment of the present invention.

[0031] Figure 3 is a diagram showing the viewing angle range of the reflected image of a variable transmittance optical laminate according to an embodiment of the present invention.

[0032] Figure 4 is a diagram showing the viewing angle range of external light of a variable transmittance optical laminate according to an embodiment of the present invention.

[0033] Figure 5 is a diagram showing the viewing angle range of the reflected image and the viewing angle range of external light of a variable transmittance optical laminate according to an embodiment of the present invention.

[0034] Figure 6 is a diagram when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle.

[0035] Figure 7 is a diagram showing the visual field range of a subject determined based on the maximum viewing angle range of the reflected image and the maximum viewing angle range of external light of the variable transmittance optical laminate.

[0036] Figures 8a to 8e is a diagram showing the laminated structure of a polarizing plate according to one or more embodiments of the present invention.

[0037] Symbol Explanation

[0038] 100: Dimming laminate

[0039] 200: Polarizing plate

[0040] 210: Polarizer

[0041] 220: Protective layer

[0042] 230: Phase difference adjustment layer

[0043] 240: Refractive index adjustment layer

[0044] 300: Transparent conductive layer

[0045] 400: Liquid crystal layer

[0046] 500: Alignment film

[0047] 600: Sealant

[0048] 700: Louvered film

[0049] 710: Adhesive surface

[0050] 720: Light-shielding pattern Detailed implementation mode

[0051] 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 passenger's field of view.

[0052] More specifically, the main feature of the present invention is that by including a shutter-type film in which a light-shielding pattern is arranged to protrude toward the indoor side, the viewing angle range of the reflected image can be adjusted.

[0053] The variable transmittance optical laminate of the present invention is particularly suitable for the technical field that can change the light transmittance according to the application of voltage. For example, it can be used for smart windows, etc.

[0054] A so-called smart window refers to an optical structure that changes the light transmittance according to the application of an electrical 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 a variable transmittance glass, a dimming glass or a smart glass, etc.

[0055] 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. They 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 cars, buses, airplanes, ships or trains.

[0056] The variable transmittance optical laminate of the present invention can also be used as a smart window in each of the above technical fields. However, since the conductive layer is directly formed on the polarizing plate and does not include 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 applying 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 therethrough, 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 also it 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 to the rear seat passenger's field of view is significantly improved during night driving.

[0057] 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.

[0058] The terms used in this specification are intended to describe embodiments and are not intended to limit the present invention. In this specification, unless 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.

[0059] 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.

[0060] 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 of one element or component to other elements or components. Spatially relative terms should be understood as terms that include different directions of elements from each other during use or operation in addition to the directions illustrated in the accompanying drawings. For example, in the case of flipping the element illustrated in the accompanying drawings, an element described as "lower" or "lower part" of another element may be placed "above" the other element. 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.

[0061] 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 transmissivity variable optical laminate of the present invention is cut in the vertical direction.

[0062] The "indoor side" used in this specification may refer to the visible side of the main user. For example, when the transmissivity variable optical laminate is applied to a vehicle, it may refer to the visible side of the passenger, that is, the inside of the vehicle. When the transmissivity variable optical laminate is applied to a building, it may refer to the visible side of the user inside the building, that is, the inside 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 transmissivity variable optical laminate, it may refer to the opposite side of the visible side of the main user.

[0063] <Transmissivity Variable Optical Laminate>

[0064] Figure 1a and Figure 1b is a diagram showing the laminated structure of the transmissivity variable optical laminate according to an embodiment of the present invention.

[0065] The transmissivity variable optical laminate of the present invention may include: a dimming laminate 100 that includes an electric field-driven liquid crystal between polarizing plates; and a louver film 700 that is disposed on at least a part of the indoor side of the dimming laminate, and the louver film includes a light-shielding pattern that protrudes toward the indoor side.

[0066] Louvered film 700

[0067] Figure 2 is a diagram showing the structure of the louver film according to an embodiment of the present invention.

[0068] 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 dimming laminate, and the louver film 700 must include a light-shielding pattern 720.

[0069] In addition to the light-shielding pattern 720, the louver film 700 of the present invention may not include an additional substrate or film for supporting the light-shielding pattern 720. In this case, the light-shielding pattern 720 may be directly formed on one surface of the dimming laminate 100. In this case, the light-shielding pattern 720 is formed on the indoor-side surface of the dimming laminate 100 and protrudes toward the indoor side. The louver film 700 of the present invention may also directly form the light-shielding pattern 720 on the indoor-side surface of the dimming 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 separation 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.

[0070] 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 an additional substrate or film for supporting the light-shielding pattern 720, and preferably may further include a transparent film.

[0071] The above light-shielding pattern may be one of a dotted line shape, a straight line shape, an oblique line shape, a corrugated shape, a serrated shape, a grid shape, and there is no particular limitation as long as the effects of the present application are achieved.

[0072] Specifically, referring to Figure 2 , it includes a shape in which light-shielding patterns 720 having a predetermined height h are formed at a predetermined interval ω2 and repeatedly on the above louver film 700. Thus, the above light-transmitting portion ω2 and light-shielding portion ω1 can be included.

[0073] Figure 3 is a view showing the viewing angle range θ1 of the reflection image of the variable transmittance optical laminate according to an embodiment of the present invention. Referring to Figure 3 , the light-shielding pattern 720 of the present invention protrudes toward the indoor side, so that the above reflection image can be blocked by the side surface of the light-shielding pattern 720. Thus, only the reflection image not blocked by the side surface of the above light-shielding pattern 720 is visible, and thus the viewing angle range of the reflection image can be adjusted.

[0074] In the variable transmittance optical laminate of the present invention, the viewing angle of the above reflection image is the angle of the reflection image with respect to a straight line perpendicular to the adhesion surface on the indoor side ( Figure 3 the dotted line in

[0075] Figure 4 It is a diagram showing the viewing angle range θ2 of external light of a transmittance-variable optical laminate according to an embodiment of the present invention. Figure 5 It is a diagram showing the viewing angle range of the reflected image and the viewing angle range of external light of a transmittance-variable optical laminate according to an embodiment of the present invention. In the present invention, the viewing angle of the above external light is the angle of the external light with respect to a straight line perpendicular to the adhesion surface on the indoor side in the vertical cross-section of the transmittance-variable optical laminate.

[0076] The transmittance-variable optical laminate according to an embodiment of the present invention can adjust the maximum viewing angle θ1 of the reflected image and the maximum viewing angle θ2 of the external light according to the light-shielding portion ω1, the light-transmitting portion ω2 of adjacent light-shielding patterns, and / or the height h of the light-shielding pattern.

[0077] As an example, when the light-shielding portion ω1 of the transmittance-variable optical laminate of the present invention is the same, the viewing angle range of the reflected image and the viewing angle range of the external light can be adjusted according to the above light-transmitting portion ω2 and the height h of the light-shielding pattern. As an example, when the light-shielding portion ω1 is the same, the smaller the width of the light-transmitting portion ω2 and the larger the height h of the light-shielding pattern, the smaller the maximum viewing angle of the reflected image. In addition, when the light-shielding portion ω1 is the same, the smaller the width of the light-transmitting portion ω2 and the larger the height h of the light-shielding pattern, the smaller the maximum viewing angle of the external light.

[0078] In addition, when the light-transmitting portion ω2 of the transmittance-variable optical laminate of the present invention is the same, the viewing angle range of the reflected image and the viewing angle range of the external light can be adjusted according to the above light-shielding portion ω1 and the height h of the light-shielding pattern. As an example, when the light-transmitting portion ω2 is the same, the larger the width of the light-shielding portion ω1 and the larger the height h of the light-shielding pattern, the smaller the maximum viewing angle of the reflected image. In addition, when the light-transmitting portion ω2 is the same, the larger the width of the light-shielding portion ω1 and the larger the height h of the light-shielding pattern, the smaller the maximum viewing angle of the external light.

[0079] In addition, regarding the height h of the above light-shielding pattern and the above light-shielding portion ω1, h / ω1 can satisfy 0.5 to 3.0. Regarding the above light-transmitting portion ω2, the aperture ratio p defined by ω2 / (ω2 + ω1)×100(%) can be 70% or more. At this time, the range of each value can be defined according to the relationship satisfying all h, ω1, and p, thereby determining the pattern shape. Further, only when all the conditions of the θ1 value being 45° to 75°, the θ2 value being 60° to 85°, and the aperture ratio (p) being 70% or more are satisfied, can a preferable light-shielding pattern be formed that ensures transmittance and suppresses the reflected image, where the reflected light cannot be seen from the subject's perspective but the external light can be seen.

[0080] When the aperture ratio (p) of the louvered film 700 of the present invention in the top view direction 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 light transmission mode of the light control laminate. Generally speaking, if the aperture ratio (p) of the louvered film 700 is low, the transmittance deteriorates. However, in this application, the light shielding pattern is inclined at a predetermined angle with respect to the adhesion surface in the vertical cross-section. Therefore, 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.

[0081] In the present invention, as described above, if the maximum viewing angle θ1 of the reflected image and the maximum viewing angle θ2 of the external light set according to the light shielding portion ω1, the light transmitting portion ω2 of the adjacent light shielding patterns and / or the height h 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 on the indoor side and / or the line of sight height of the above-mentioned main user, the antireflection function and the external light transmission function for any shape on the indoor side can be maximized more precisely.

[0082] In an example of the present invention, when the light control laminate of the present invention is used as a sunroof of a vehicle, the line of sight height of the above-mentioned main user may be the straight-line distance ( Figure 7 D1) from the ceiling of the vehicle to the field of view of the vehicle occupant, preferably the rear seat occupant. The distance from the variable transmittance optical laminate to the main user on the indoor side may be the shortest distance ( Figure 7 L) from the center between the adjacent light shielding patterns to the position of the main user.

[0083] 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 in such a way 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 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 in such a way 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 maximum viewing angle θ2 of the external light, and the light shielding portion ω1, the light transmitting portion ω2 of the light shielding pattern of the louvered film of the present invention and / or the height h of the light shielding pattern can be set in such a way as to achieve such a viewing angle range.

[0084] As an example of the present invention, the range of the maximum viewing angle of the reflected image may be 45° to 75°, and the viewing angle of the above-mentioned 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.

[0085] As an example of the present invention, the range of the maximum viewing angle of external light transmitted from the outside may 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 transmissivity variable optical laminate.

[0086] 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 dazzle the rear seat passengers' view with the indoor side reflection image of the front seat panel or the like, and at the same time not to reduce the transmissivity of external light, the range of the rear seat passengers' view is important. Therefore, the range where the rear seat passengers' view 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 reflection image.

[0087] The appropriate range of the curvature of the transmissivity variable 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 passengers to the outermost surface on the indoor side of the ceiling, and specifically, it can satisfy 300 mm to 600 mm, and preferably can satisfy 300 mm to 500 mm.

[0088] Figure 6 It is a view showing an example of applying the transmissivity variable optical laminate of the present invention to a sunroof of a vehicle. The sunroof located at the upper part of the vehicle can be in a flat form or a curved form. More specifically, Figure 6 It is a view showing both the case where the transmissivity variable optical laminate applied to the vehicle is in a curved form and the case where it is in a flat form. At this time, for the case where the transmissivity variable optical laminate is in a curved form and the case where it is in a flat form, according to the degree of bending of the transmissivity variable optical laminate, the reflection angle formed by the light emitted from the front seat panel in the shutter film will change, and the height h of the light-shielding pattern, the light-shielding part ω1, and the light-transmitting part ω2 can be adjusted so that the reflection image of the front seat panel will not dazzle the rear seat passengers' view and the transmissivity of external light will not be reduced. Within the range of achieving the object of the present invention, the height h of the plurality of light-shielding patterns, the light-shielding part ω1, and the light-transmitting part ω2 can be different from each other.

[0089] At this time, the slope on the curved surface of the transmissivity variable optical laminate can be changed according to the type and purpose of the vehicle to which it is applied, so the optimal range is not particularly limited.

[0090] In one example of the present invention, in order not to cause glare to the field of view of the rear-seat passengers due to the reflection image on the indoor side of the front seat panel or the like, and at the same time not to reduce the transmittance of external light, the range of the field of view of the rear-seat passengers is important. Therefore, the range where the field of view of the rear-seat passengers is located must be adjusted to include the viewing angle range of external light but not include the viewing angle range of the reflection image.

[0091] 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 passengers to the outermost surface on the indoor side of the ceiling, and specifically, it can satisfy 300 mm to 600 mm, and preferably can satisfy 300 mm to 500 mm.

[0092] Figure 7 It is a diagram showing an example of the above variable transmittance optical laminate. Hereinafter, with reference to Figure 7 to explain in more detail the height h of the light-shielding pattern, the light-shielding portion ω1, and the light-transmitting portion ω2 that do not cause glare to the field of view of the rear-seat passengers due to the reflection image of the front seat panel and at the same time do not reduce the transmittance of external light. Figure 7 The reflection image starting from the front seat panel and reaching the field of view of the passengers and the external light passing through from the outside and reaching the field of view of the passengers are shown. For example, if the light-transmitting portion on the louvered film where no light-shielding pattern is formed is set as ω2, the straight-line distance from the point where the light from the front seat panel reaches the variable transmittance optical laminate to the ceiling of the rear-seat passengers is set as L, the distance from the place where the external light reaches the field of view of the rear-seat passengers to the ceiling of the rear-seat passengers is set as D2, and the distance from the place where the reflected light reaches the field of view of the rear-seat passengers to the ceiling of the rear-seat passengers is set as D1, the meaning of the value of D1 - D2 is △D. The above △D value is the field of view range of the rear-seat passengers that does not cause glare to the field of view of the rear-seat passengers due to the reflection image of the front seat panel and at the same time does not reduce the transmittance of external light. Therefore, the field of view of the rear-seat passengers can be located within the range of △D.

[0093] The △D value is the field of view range of the subject that does not cause glare to the field of view of the subject and at the same time does not reduce the transmittance of external light. Specifically, if the position of the eyes 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 passengers 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.

[0094] The above ΔD value can be determined based on the light-shielding portion ω1, the light-transmitting portion ω2 of the light-shielding pattern, and the height h of the light-shielding pattern. Specifically, since the viewing angle of the reflected image is tan^(-1)(ω2 / 2h), the viewing angle of the external light is tan^(-1)(ω2 / h), 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) / tan(θ2). Therefore, the viewing angles θ1 and θ2 are adjusted by the light-shielding portion ω1 and the height h of the light-shielding pattern, and the values of D1 and D2 are adjusted according to the values of the above θ1, θ2, and the light-transmitting portion ω2, thereby determining the ΔD range value. At this time, the larger the value of θ2, the smaller the value of θ1, and the larger the range of ΔD. Preferably, D2 can be 500 mm or less, and D2 + ΔD can be 300 mm or more.

[0095] As an example, referring to Figure 7 It can be confirmed that, from the perspective of a subject located at 1000 mm (L) from the center between adjacent light-shielding patterns, if D2, which determines the starting point of the ΔD value range, satisfies 500 mm or less and the range of external light transmission becomes wider, and D1 (D2 + ΔD), which determines the end point of the ΔD value range, satisfies 300 mm or more, the range of the reflected image blocking the field of view of the subject also becomes wider.

[0096] The aperture ratio (p) of the above variable transmittance optical laminate can be determined based on the above light-shielding portion ω1 and the light-transmitting portion ω2. As an example, it can be represented by the value of ω2 / (ω2 + ω1)×100.

[0097] At this time, when the height of the above light-shielding pattern is set to h and the above light-shielding portion is set to ω1, h / ω1 satisfies 0.5 to 3.0. When the above light-transmitting portion is set to ω2, the aperture ratio (p) defined by ω2 / (ω2 + ω1)×100 (%) can be 70% or more. The ranges of each value can be limited according to the relationship satisfying all h, ω1, and p, thereby determining the pattern shape.

[0098] When the aperture ratio (p) of the louvered film 700 of the present invention in the top view direction is 70% or more, it has the advantages of being able to ensure the antireflection performance on the surface of the light control laminate and maintaining a high transmittance in the light transmission mode of the light control laminate.

[0099] In an example of the present invention, the above louvered film 700 includes a light-shielding pattern 720. The above light-shielding pattern 720 can be directly formed on the light control laminate. In addition, it can also be formed on a separate transparent film and attached to the light control laminate. When the above 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 transparent film and the light control laminate.

[0100] The above transparent film can be a film developed in the past or in the future. The material of the above transparent film layer used in the manufacturing of the louvered film 700 used 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 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.

[0101] The above adhesive layer (not shown for convenience) can be formed using an adhesive, and preferably has excellent heat-resistant adhesiveness. The above 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.

[0102] The above adhesive can be an adhesive developed in the past or in the future. In one or more embodiments, an acrylic adhesive, a rubber-based adhesive, a silicone-based adhesive, a urethane-based adhesive, a polyvinyl alcohol-based adhesive, a polyvinylpyrrolidone-based adhesive, a polyacrylamide-based adhesive, a cellulose-based adhesive, a vinyl alkyl ether-based adhesive, etc. can be used. The above adhesive has no particular limitation as long as it has adhesiveness and viscoelasticity. Considering ease of acquisition and other aspects, an acrylic adhesive is preferably used. For example, it can contain a (meth)acrylate copolymer, a crosslinking agent, and a solvent, etc. In addition, selection can also be considered in terms of the adhesion characteristics to the light-shielding pattern 720 and ensuring viscoelasticity. For example, the adhesive / bonding layer can contain an acrylate-based pressure-sensitive adhesive (PSA) substance or an optically clear adhesive (OCR) substance.

[0103] The above light-shielding pattern 720 can be applied without limitation to materials used for light-shielding purposes. For example, it can be manufactured by containing 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. A composition containing a black pigment dispersion and / or a black dye can be used as the main component, and further contains a resin, a polymerization initiator, and additional additives as needed.

[0104] The method for forming the above-described light-shielding pattern 720 is not particularly limited. As an example, the following methods can be applied: a method of forming a groove on the adhesion surface 710 and filling it with a material for forming the above-described light-shielding pattern 720; or a method of manufacturing a photosensitive resin composition for forming the above-described light-shielding pattern 720 and forming the light-shielding pattern 720 on the above-described adhesion surface 710 by a photolithography method.

[0105] The above-described 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.

[0106] Dimming laminate 100

[0107] The light-adjusting laminate of the present invention is characterized in that it contains 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 reflection image, which are the main objects of the present invention, can be maximized.

[0108] Specifically, the light-adjusting laminate of the present invention includes a first polarizing plate, a first transparent conductive layer formed on one surface of the first polarizing plate, a second polarizing plate 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 is formed in direct contact with one of the first polarizing plate and the second polarizing plate.

[0109] FIG. 8 is a diagram showing the laminated structure of polarizing plates according to one or more embodiments of the present invention.

[0110] Referring to FIG. 8, the above-described 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 8a and Figure 8b ), 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-described one surface (refer to Figure 8c), which may include a polarizer 210, a protective layer 220 laminated on one side of the polarizer, and a retardation adjusting layer 230 and a refractive index adjusting layer 240 laminated in sequence on the other side of the polarizer 210 opposite to the one side (see Figure 8d ), which may include a polarizer 210, a protective layer 220 laminated on one side of the polarizer, and a protective layer 220 and a retardation adjusting layer 230 laminated in sequence on the other side of the polarizer 210 opposite to the one side (see Figure 8e ).

[0111] 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 may be used.

[0112] 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 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.

[0113] 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.

[0114] The above-mentioned reactive liquid crystal compound may, for example, 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 by 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.

[0115] 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.

[0116] The above 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. As the above dichroic dye, a dichroic dye developed in the past or in the future can be used. For example, it may include one or more selected from the group consisting of azo dyes, anthraquinone dyes, perylene dyes, merocyanine dyes, azomethine dyes, phthaloperylene dyes, indigo dyes, dioxadine dyes, polythiophene dyes, and phenoxazine dyes.

[0117] The above liquid crystal coating composition may further contain a solvent capable of dissolving the above reactive liquid crystal compound and the above dichroic dye. For example, propylene glycol monomethyl ether acetate (PGMEA), methyl ethyl ketone (MEK), xylene, chloroform, etc. can be used. In addition, the above liquid crystal coating composition may also contain a leveling agent, a polymerization initiator, etc. within a range that does not hinder the polarization characteristics of the coating film.

[0118] The above 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.

[0119] As Figure 8a and Figure 8b As illustrated, the above protective layer 220 may be formed in direct contact with one or both surfaces of the polarizer 210, but is not limited thereto. For example, the above protective layer may also be used in a multilayer structure in which one or more protective layers are continuously laminated, and may be formed in direct contact with other functional layers.

[0120] In one or more embodiments, the above-mentioned 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).

[0121] As Figure 8c and Figure 8d illustrated, the above-mentioned retardation adjustment layer 230 may be formed in direct contact with one surface of the polarizer 210, but is not limited thereto. For example, as Figure 8e illustrated, the above-mentioned retardation adjustment 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 adjustment layer 230 in this order.

[0122] The above-mentioned retardation adjustment 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.

[0123] 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), acrylic 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.

[0124] The method for obtaining the above-mentioned polymer stretched film is not particularly limited. For example, it can be obtained by stretching the above-mentioned polymer material after forming it into a film shape. The method for forming it 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, or 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 through melt-kneading during extrusion molding. In addition, a solvent common to various resin components, such as chloroform, dichloromethane, etc., can also be used to dissolve various resin components and then perform casting, drying, and curing to thereby perform casting molding on the unstretched film.

[0125] 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.

[0126] 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.

[0127] 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.

[0128] 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, etc. 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.

[0129] Specifically, the above transparent conductive layer 300 is laminated adjacent 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.

[0130] 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.

[0131] The above refractive index adjustment layer 240 is not particularly limited 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 for forming 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.

[0132] 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.

[0133] 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 .

[0134] 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.

[0135] 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.

[0136] 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.

[0137] 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) disposed on one side of the polarizing plate 200 .

[0138] 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.

[0139] 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. 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 formed by mixing metal powder and a curable polymer binder, and the nanowire may be, for example, a silver nanowire (AgNW).

[0140] 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.

[0141] 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.

[0142] The above-mentioned liquid crystal layer 400 may include a liquid crystal compound and a spacer. For example, as illustrated in FIG. 1, it may refer to the region defined by the first alignment film 500-1, the second alignment film 500-2, and the sealant 600.

[0143] The above liquid crystal compound is not particularly limited as long as it is driven by an electric field and can control the light transmittance, and liquid crystal compounds developed in the past or in the future can be used. For example, the content regarding the reactive liquid crystal compound of the above coating type polarizer can be similarly applied.

[0144] The liquid crystal behavior mode of the above liquid crystal layer 400 is not particularly limited. For example, as illustrated in FIG. 1, it can be driven by a twisted nematic (TN) mode. In addition to this, it can also be driven by a supertwisted nematic (STN) mode, a vertical alignment (VA) mode, an electrically controlled birefringence (ECB) mode, etc.

[0145] The above spacer can include at least one or more spacers such as 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 viewed from the top view direction, considering the improvement of the visibility of the user 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.

[0146] 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.

[0147] 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 curing it.

[0148] 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.

[0149] 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.

[0150] 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.

[0151] As the base resin of the above-mentioned sealant 600, for example, an acrylate-based resin, an epoxy-based resin, a urethane-based resin, a phenol-based resin, or a mixture 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.

[0152] 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.

[0153] <Smart Windows and Sunroofs>

[0154] In addition to the above-described transmittance-variable optical laminate, the present invention further includes a smart window including the above-described transmittance-variable 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.

[0155] For example, in an automobile including the smart window of the present invention, vehicle glass may be bonded to both surfaces of the transmittance-variable optical laminate, and the above-described vehicle glass may include the above-described shutter film. For example, the smart window including the above-described vehicle glass may 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 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 louver film includes a light-shielding pattern that protrudes toward a room's interior.

2. The variable transmittance optical layered body according to claim 1, wherein the maximum viewing angle θ1 of the reflected image of the variable transmittance optical layered body is in the range of 45° to 75°. The viewing angle of the reflected image is the angle of the reflected image relative to a straight line perpendicular to the adhesion surface on the indoor side in a vertical cross section of the variable transmittance optical layered body.

3. The variable transmittance optical layered body according to claim 1, wherein the maximum viewing angle θ2 of external light transmitted from the outside of the variable transmittance optical layered body is in the range of 60° to 85°, The viewing angle of the external light is the angle of the external light relative to a straight line perpendicular to the adhesion surface on the indoor side in a vertical cross section of the variable transmittance optical laminate.

4. The variable transmittance optical laminate according to claim 1, wherein the louver film includes a light-transmitting portion where the light-shielding pattern is not formed and a light-shielding portion where the light-shielding pattern is formed. When the height of the shading pattern is set to h and the shading portion is set to ω1, h / ω1 is 0.5 to 3.0, and when the light-transmitting portion is set to ω2, the aperture ratio p defined by ω2 / (ω2+ω1)×100(%) is greater than 70%.

5. The variable transmittance optical stack according to claim 1, wherein the light-adjusting 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.

6. The variable transmittance optical stack according to claim 5, 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. 7 . The variable transmittance optical laminate according to claim 5 , 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. 8 . The variable transmittance optical laminate according to claim 5 , wherein at least one of the first polarizing plate and the second polarizing plate has a thickness of 30 μm to 200 μm. 9 . The variable transmittance optical stack according to claim 5 , wherein the liquid crystal layer includes one or more spacers selected from the group consisting of spherical spacers and columnar spacers. 10 . The variable transmittance optical laminate according to claim 5 , further comprising alignment films on both surfaces of the liquid crystal layer. 11 . A skylight comprising the variable transmittance optical laminate according to claim 1 .

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