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, the light-shielding pattern being inclined at a predetermined angle with respect to an adhesive surface in a vertical cross-section. The optical laminate according to the present invention exhibits an excellent anti-reflection function without reducing the transmittance of external light rays 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 Patent Publication 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 louver film disposed on at least a part of the indoor side of the dimming laminate, wherein the louver film includes a light-shielding pattern that is inclined at a predetermined angle with respect to the adhesion surface in a vertical cross section.

[0014] In one embodiment of the present invention, the length a of the inclined surface of the light-shielding pattern projected onto the adhesion surface in a vertical cross section of the light-shielding pattern may be 5 to 50% of the light-shielding portion ω1.

[0015] In one embodiment of the present invention, the range of the maximum viewing angle 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 a vertical cross section of the variable transmittance optical laminate.

[0016] In one embodiment of the present invention, the range of the maximum viewing angle 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 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 a vertical cross section of the variable transmittance optical laminate.

[0017] In another embodiment of the present invention, the light-shielding pattern may be formed by at least partial dislocation lamination of two or more unit patterns.

[0018] In another embodiment of the present invention, the louver film includes a pattern interval 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 set to h and the light-shielding portion is set to ω1, h / ω1 may be 0.5 to 4.0. When the pattern interval is set to ω2 and the vertical light-transmitting portion is set to ω3, the aperture ratio p defined by ω3 / (ω2 + ω1) × 100 (%) with respect to the direction perpendicular to the plane may be 70% or more.

[0019] In another embodiment of the present invention, the light-shielding pattern may protrude toward the indoor side.

[0020] 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.

[0021] 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 a transparent conductive oxide, a metal, a carbon-based material, a conductive polymer, a conductive ink, and a nanowire.

[0022] 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.

[0023] 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.

[0024] In another embodiment of the present invention, the liquid crystal layer may include one or more spacers selected from the group consisting of a ball spacer and a column spacer.

[0025] In another embodiment of the present invention, an alignment film may also be included on both surfaces of the liquid crystal layer.

[0026] The present invention provides a skylight including the above-described variable transmittance optical laminate.

[0027] Advantages of the Invention

[0028] According to an embodiment of the present invention, the optical laminate includes a shutter-type film having a light-shielding pattern protruding toward the indoor side, thereby exhibiting an excellent antireflection function without reducing the transmittance of external light.

[0029] The optical laminate according to an embodiment of the present invention can achieve a form in which it is in direct contact because the transparent conductive layer is directly formed on the polarizing plate itself, rather than the transparent conductive layer being formed through a separate substrate and attached to the polarizing plate. Therefore, an optical laminate with a thin overall thickness of the optical laminate and favorable bending characteristics can be provided.

[0030] Furthermore, as described above, since the overall thickness of the optical laminate becomes thinner, in the case of applying the shutter-type film with a unique structure of the present invention, there is an advantage that the antireflection function and the transmittance adjustment function can be maximized.

[0031] Furthermore, when the variable transmittance optical laminate of the present invention is used as a sunroof, it is possible to improve the phenomenon that 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

[0032] Figure 1a and Figure 1b are diagrams showing the laminated structure of the variable transmittance optical laminate according to an embodiment of the present invention (the inclined light shielding pattern is not shown).

[0033] Figure 2a and Figure 2b are diagrams showing the structure of the shutter-type film according to an embodiment of the present invention.

[0034] Figure 3 is a diagram showing the angle with the adhesion surface when the light shielding pattern in the present invention is a single layer.

[0035] Figure 4 is a diagram showing the unit pattern of the light shielding pattern when the light shielding pattern in the present invention is a multi-layer.

[0036] Figures 5a - 5c is a diagram showing the substantial inclination formed by the unit pattern when the light shielding pattern in the present invention is a multi-layer.

[0037] Figure 6 is a diagram showing the travel of the reflected light of the variable transmittance optical laminate according to an embodiment of the present invention.

[0038] Figure 7 is a diagram showing the travel of the external light of the variable transmittance optical laminate according to an embodiment of the present invention.

[0039] Figure 8 is a diagram showing the reflected light when the viewing angle of the reflected image is maximum in the variable transmittance optical laminate in which the light shielding pattern is formed in a single layer or a multi-layer with a substantial inclination according to an embodiment of the present invention.

[0040] Figure 9It is a diagram showing the visual field range of a subject determined based on the maximum viewing angle range θ1 of the reflected image of the variable transmittance optical laminate described above and the maximum viewing angle range θ2 of external light.

[0041] Figures 10a - 10e It is a diagram showing the laminated structure of a polarizing plate according to one or more embodiments of the present invention.

[0042] Symbol Explanation

[0043] 100: Dimming laminate

[0044] 200: Polarizing plate

[0045] 210: Polarizer

[0046] 220: Protective layer

[0047] 230: Phase difference adjusting layer

[0048] 240: Refractive index adjusting layer

[0049] 300: Transparent conductive layer

[0050] 400: Liquid crystal layer

[0051] 500: Alignment film

[0052] 600: Sealant

[0053] 700: Louver film

[0054] 710: Adhesive surface

[0055] 720: Light shielding pattern

[0056] 721, 722, 723: First unit pattern, second unit pattern, third unit pattern Detailed Description of the Invention

[0057] 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 and advantageous for bending characteristics, but also has 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 field of view of the rear seat passengers.

[0058] More specifically, the main feature of the present invention is that by including a light shielding pattern arranged to protrude toward the indoor side, the viewing angle range of the reflected image can be adjusted.

[0059] 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.

[0060] 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 to 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.

[0061] 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 configured at the openings of buildings, and can also be used as highway road signs, billboards, scoreboards, clocks, or advertising screens, and can replace the glass of transportation tools such as windows or skylights of automobiles, buses, airplanes, ships, or trains.

[0062] 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 and does not include a separate substrate for forming the conductive layer, it has a thin thickness and is beneficial to bending characteristics, and is particularly suitable for vehicle or building smart windows. In one or more embodiments, the smart window applying the variable transmittance optical laminate of the present invention can be used for transportation tools, such as the front window, rear window, side window, and skylight of an automobile, or building windows, etc. In addition to the use of blocking external light, it can also be used for internal space partitioning or privacy protection purposes in automobiles or buildings, such as internal partitions, 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 passing through, 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 skylight of a vehicle, it has the following advantages: not only is it thin in thickness and beneficial to bending characteristics, but also it has an anti-reflection function without reducing the transmittance of external light, so it significantly improves the glare caused by the reflected image of the front seat panel reflected from the skylight to the rear seat passengers' vision during night driving.

[0063] 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 the 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 interpreted only limited to the matters described in these drawings.

[0064] 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.

[0065] As used in this specification, the terms "comprises" and / or "comprising" are used in a sense that does not exclude 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.

[0066] As illustrated in the drawings, spatially relative terms such as "below", "bottom surface", "lower part", "above", "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 directions other than those illustrated in the drawings and that are different from each other when the elements are in use or operation. For example, when the element illustrated in the drawings is flipped, the element described as "below" or "lower part" of another element may be placed "above" the other element. Therefore, the exemplary term "below" may include both the below and above directions. The element may also be oriented in other directions, so spatially relative terms may be interpreted according to the orientation.

[0067] The "top view direction" used in this specification may be interpreted as a 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 in the vertical direction.

[0068] 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 inside 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 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 transmittance variable optical laminate, may refer to the opposite side of the visible side of the main user.

[0069] <Transmittance variable optical laminate>

[0070] Figure 1a and Figure 1b FIG. is a diagram showing the laminated structure of a variable transmittance optical laminate according to an embodiment of the present invention (the inclined light shielding pattern is not shown).

[0071] The variable transmittance optical laminate of the present invention is characterized by comprising: a dimming laminate 100 which includes an electric field-driven liquid crystal between polarizing plates; and a louver film 700 which is disposed on at least a part of the indoor side of the dimming laminate. In particular, the louver film 700 includes a light shielding pattern 720 which is inclined at a predetermined angle with respect to the adhesion surface in a vertical cross section.

[0072] The adhesion surface of the present invention refers to the layer to which the light shielding pattern 720 of the 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 dimming laminate 100 without an additional substrate or film, the adhesion surface may be one surface of the dimming laminate 100, preferably the indoor side surface of the dimming laminate 100. For example, it may be a polarizing plate 200, a polarizer 210, a protective layer 220, a phase difference adjusting layer 230 or a refractive index adjusting layer 240 which are laminated. 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 dimming laminate, the adhesion surface may be an additional substrate or film such as a transparent film.

[0073] Louvered film 700

[0074] Figure 2a and Figure 2b FIG. is a diagram showing the structure of the louver film according to an embodiment of the present invention.

[0075] 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.

[0076] In addition to the light-shielding pattern 720, the louvered film 700 of the present invention may no longer include an additional substrate or film for supporting the light-shielding pattern 720. In this case, the above light-shielding pattern 720 may be directly formed on one surface of the light-adjusting laminate 100. In this case, the above light-shielding pattern 720 is formed on the indoor-side surface of the light-adjusting laminate 100 and protrudes toward the indoor side. The louvered film 700 of the present invention may directly form the light-shielding pattern 720 on the indoor-side surface of the light-adjusting laminate 100. In this case, it has the advantage of minimizing the overall thickness of the variable transmittance optical laminate of the present invention, and a method of pre-forming a pattern including a separation layer and then transferring it through an adhesion surface and an adhesive / cement may be used. At this time, as the thickness of the adhesive / cement is minimized, the overall thickness of the variable transmittance optical laminate will become thinner.

[0077] In addition, as Figure 1b shown, in addition to the light-shielding pattern 720, the louvered 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.

[0078] The above light-shielding pattern 720 is characterized in that it is inclined at a predetermined angle θ with respect to the adhesion surface in a vertical cross-section. The meaning that the above light-shielding pattern 720 of the present invention is inclined at a predetermined angle with respect to the above adhesion surface in a vertical cross-section includes a substantial inclination. In the present invention, the meaning of substantial inclination may be that the overall shape exhibited by two or more light-shielding patterns 720, for example, as will be described later, when there are multiple layers of light-shielding patterns, the overall shape connecting a point outside them is inclined in the direction toward the user in a vertical cross-section.

[0079] Specifically, referring to Figure 2a and Figure 2b , the louvered film 700 of the present invention includes a shape in which light-shielding patterns 720 having a predetermined height h are formed at a predetermined interval ω2 and repeated. At this time, since the light-shielding patterns 720 are formed obliquely, it may include a vertical light-transmitting portion ω3 between the inclined light-shielding patterns and a light-shielding portion ω1 formed by the light-shielding patterns.

[0080] More specifically, the above-described light-shielding pattern 720 of the present invention being inclined at a predetermined angle with respect to the above-described adhesion surface in a vertical cross-section may mean forming an angle that is not perpendicular to the above-described adhesion surface. More specifically, the above-described light-shielding pattern 720 of the present invention may be inclined in a direction toward the user in a vertical cross-section. As an example, in the case where the variable transmittance optical laminate of the present invention is applied to a vehicle sunroof, the above-described light-shielding pattern 720 may be inclined in a direction toward the rear seat passenger of the vehicle. Therefore, it has the advantages of minimizing the transmittance loss of external light for the rear seat passenger of the vehicle and significantly improving the glare caused by the reflected image to the rear seat passenger's field of view.

[0081] The light-shielding pattern 720 of the present invention, as an inclined pattern, may be a single layer or multiple layers.

[0082] Figure 3 It is a diagram showing the angle between the light-shielding pattern of the present invention and the adhesion surface when the light-shielding pattern is a single layer. When the above-described light-shielding pattern is a single layer, the above-described light-shielding pattern may be one of a polygon, a circle, a semi-circle, a dotted line shape, a straight line shape, a slanted line shape, a corrugated shape, a serrated shape, a grid shape, and there is no particular limitation on its cross-sectional shape as long as the effects of the present application are achieved. Preferably, as Figure 3 shown, the cross-section of the light-shielding pattern may be an inclined quadrilateral shape, and thus a light-shielding pattern inclined at a predetermined angle θ can be achieved.

[0083] The angle between the above-described light-shielding pattern 720 of the present invention and the adhesion surface in a vertical cross-section may be the same or different from each other depending on the position. As an example, in the case where the variable transmittance optical laminate of the present invention is applied to a vehicle sunroof, with respect to the angle between the above-described light-shielding pattern 720 and the adhesion surface in a vertical cross-section, the closer to the rear seat passenger of the vehicle, the larger the angle may be, and the farther from the rear seat passenger, the smaller the angle may be, but it is not limited thereto. In this case, the transmittance of external light for the rear seat passenger of the vehicle can be improved more effectively.

[0084] Figure 4 It is a diagram showing the unit pattern of the light-shielding pattern when the light-shielding pattern of the present invention is multiple layers. When the light-shielding pattern of the present invention is multiple layers, a light-shielding pattern that is inclined as a whole in a predetermined direction may be formed by laminating two or more unit patterns offset from each other. In the present invention, the meaning of offset lamination may be that the entire light-shielding pattern of the present invention is laminated in an inclined manner. The cross-section of the above-described unit pattern may be a polygon, a circle, or a semi-circle, and preferably may be a quadrilateral shape. In this case, a light-shielding pattern with an inclined cross-section can be achieved by photolithography, and thus there are great advantages in manufacturing.

[0085] More specifically, in FIG. 5, the light-shielding pattern is a three-layer multi-layer structure, including a first unit pattern 721, a second unit pattern 722, and a third unit pattern 723. This is only for illustrating one embodiment of the present invention, and the present invention is not limited thereto. When the light-shielding pattern of the present invention is multi-layered, the overall shape, included angle, spacing ω2 between patterns, and height h of the light-shielding pattern of the present invention can be adjusted by adjusting the width ω1 of multiple unit patterns, their respective heights, the number of stacked layers, the degree of misalignment with each other, etc. Thus, the transmissivity variable optical laminate of the present invention can adjust the range of the viewing angle of the reflected image and the range of the viewing angle of external light.

[0086] Figure 5a and Figure 5b is a diagram showing the substantial inclination formed by the unit pattern. As described above, the meaning that the light-shielding pattern 720 of the present invention is inclined at a predetermined angle θ with respect to the adhesion surface in the vertical cross-section includes a substantial inclination. As an example, when the light-shielding pattern of the present invention is multi-layered, it may be a line connecting the outermost points of two or more unit patterns constituting the light-shielding pattern ( Figure 5a ) or a line connecting the centers of two or more unit patterns constituting the light-shielding pattern ( Figure 5b ) that is inclined at a predetermined angle θ with respect to the adhesion surface.

[0087] Figure 5c is a diagram showing an example of adjusting the substantial inclination of the light-shielding pattern of the present invention by adjusting the degree of misalignment with each other of multiple unit patterns when the light-shielding pattern of the present invention is multi-layered.

[0088] The light-shielding pattern 720 of the present invention can protrude toward the indoor side. Examples such as Figure 6 etc. are used to elaborate in detail on the blocking function of the viewing angle of the reflected image of the transmissivity variable optical laminate of the present invention based on such a shape.

[0089] Figure 6 is a diagram showing the travel of the reflected light of the transmissivity variable optical laminate according to an embodiment of the present invention.

[0090] Referring to Figure 6 , since the light-shielding pattern 720 of the present invention protrudes toward the indoor side, the above-mentioned reflected image can be blocked by the side surface of the light-shielding pattern 720. Thus, the range of the viewing angle of the reflected image can be adjusted by making only the reflected image not blocked by the side surface of the light-shielding pattern 720 visible.

[0091] Figure 7 is a diagram showing the travel of the external light of the transmissivity variable optical laminate according to an embodiment of the present invention. As shown in Figure 7As shown, since the light-shielding pattern 720 of the present invention is configured to be inclined at a predetermined angle θ in a vertical cross-section, it is possible to minimize the transmittance loss of external light in the inclined direction.

[0092] Figure 8 It is a diagram showing the reflected light when the viewing angle of the reflected image is maximized in a transmissivity variable optical laminate in which the light-shielding pattern of an embodiment of the present invention is formed in a single layer or multiple layers and is substantially inclined.

[0093] As described above, in one embodiment of the present invention constituted by a light-shielding pattern of a single layer or multiple layers, in a vertical cross-section, with respect to the above-mentioned adhesion surface, the patterns are formed at a predetermined interval ω2. At this time, the length of the inclined surface of the light-shielding pattern formed by the substantially inclined pattern shape projected onto the adhesion surface is referred to as the inclined surface projection length a. In addition, referring to Figure 8 , the above-mentioned inclined surface projection length a can be regarded as the length obtained by subtracting the vertical light-transmitting portion ω3 from the pattern interval ω2. The above-mentioned inclined surface projection length a can be 5 to 50% of the light-shielding portion ω1. When the pattern sizes are the same, the smaller the angle θ at which the light-shielding pattern is substantially inclined with respect to the adhesion surface, the longer the inclined surface projection length a.

[0094] The transmissivity variable optical laminate of one embodiment of the present invention can adjust the maximum viewing angle θ1 of the reflected image and the maximum viewing angle θ2 of external light according to the light-shielding portion ω1 of adjacent light-shielding patterns, the pattern interval ω2, the height h of the light-shielding pattern, and / or the inclined surface projection length a.

[0095] As an example, the transmissivity variable optical laminate of the present invention can adjust the viewing angle range θ1 of the reflected image and the viewing angle range θ2 of external light according to the above-mentioned pattern interval ω2, the height h of the light-shielding pattern, and / or the inclined surface projection length a when the light-shielding portion ω1 is the same. As an example, referring to the experimental example of the present invention, when the light-shielding portion ω1 is the same, the smaller the width of the pattern interval ω2 and the larger the height h of the light-shielding pattern, the smaller the maximum viewing angle θ1 of the reflected image. In addition, when the light-shielding portion ω1 is the same, the smaller the width of the pattern interval ω2 and the larger the height h of the light-shielding pattern, the smaller the maximum viewing angle θ2 of external light.

[0096] In addition, the transmissivity variable optical laminate of the present invention can adjust the viewing angle range θ1 of the reflected image and the viewing angle range θ2 of external light according to the above-mentioned light-shielding portion ω1 and the height h of the light-shielding pattern when the pattern interval ω2 is the same.

[0097] 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 4.0. Regarding the pitch ω2 between the above patterns 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 relationships satisfying all of 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 plan 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-transmitting 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 in a form 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 in the inclined direction, a relatively high transmittance can be achieved even when the aperture ratio is low.

[0099] 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 pitch ω2 between adjacent light-shielding patterns, the height h of the light-shielding pattern, and / or the inclined surface projection length a 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 above main user, the antireflection function and the external light transmission function for any shape on the indoor side can be maximized more precisely.

[0100] 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 main user can be the straight-line distance ( Figure 9 D1) from the ceiling of the vehicle to the field of view of the vehicle occupants, preferably the rear seat occupants. The distance from the above variable transmittance optical laminate to the main user located on the indoor side can be the shortest distance ( Figure 9 L') from the center between adjacent light-shielding patterns to the position of the main user.

[0101] In one 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 maximum viewing angle θ2 of the external light, the antireflection function and the external light transmittance 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 maximum viewing angle θ2 of the external light, and the light shielding portion ω1, the pitch ω2 between patterns, the height h of the light shielding pattern, and / or the inclined surface projection length a of the louvered film of the present invention can be set to achieve such a viewing angle range.

[0102] More specifically, referring to Figure 9 which illustrates an example of the present invention, for the variable transmittance optical laminate having an arbitrary light shielding pattern formed thereon, the place where the light starting from the vehicle front seat panel and reaching the occupant's field of view at the maximum viewing angle θ1 of the reflected image is reflected in the above louvered film can be the place where the inclined surface projection length a of the light shielding pattern is shifted, rather than the center of the pitch ω2 between patterns.

[0103] As an example of the present invention, the range θ1 of the maximum viewing angle 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.

[0104] 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.

[0105] In one 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 field of view of the rear seat occupant by 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 rear seat occupant's field of view is located is important. Therefore, the range where the rear seat occupant's field of 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 reflected image.

[0106] 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, and preferably can satisfy 300 mm to 500 mm.

[0107] Figure 9 FIG. is a diagram showing an example of the variable transmittance optical laminate. Hereinafter, with reference to Figure 9 to more specifically describe the height h of the light shielding pattern, the light shielding portion ω1, the pitch ω2 between the patterns, and the inclined surface projection length a that do not cause glare in the field of view of the rear seat passenger for the reflected image of the front seat panel and do not reduce the transmittance of external light.

[0108] Figure 9 FIG. 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 pitch between the patterns where no light shielding pattern is formed on the louvered film is set as 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 as 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 as 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 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 passenger that does not cause glare in the field of view of the rear seat passenger for the reflected image of the front seat panel and does not reduce the transmittance of external light. Therefore, the field of view of the rear seat passenger can be within the range of △D.

[0109] The △D value is the field of view range of the subject that does not cause glare in the field of view of the subject for the reflected image and does not reduce 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.

[0110] The above ΔD value can be determined based on the light-shielding portion ω1 of the light-shielding pattern, the pitch ω2 between patterns, the height h of the light-shielding pattern, and the inclined surface projection length a. Specifically, the viewing angle of the reflected image is tan^(-1)(ω2 / 2h), the viewing angle of the external light is tan^(-1)((ω2 + a) / 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 + a) / 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 above values of θ1, θ2, the pitch ω2 between patterns, and the inclined surface projection length a, thereby determining the ΔD range value.

[0111] In addition, 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.

[0112] At this time, when the inclined surface projection length a increases, it may cause a loss of the aperture ratio. However, since the end point of ΔD moves away from the upper transmissivity variable optical laminate as the value of θ1 decreases, the range of ΔD can be widened.

[0113] As an example, referring to Figure 9 It can be confirmed that from the perspective of a subject at a position L' of 1000 mm 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 at the same time, 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 in the field of view of the subject is also widened.

[0114] 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-adjusting laminate. In addition, it can also be formed on a separate transparent film and attached to the light-adjusting 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-adjusting laminate.

[0115] 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 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-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.

[0116] 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.

[0117] 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 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, it can also be selected by considering ensuring the adhesion characteristics and viscoelasticity with the light-shielding pattern 720. For example, the adhesive / bonding layer can contain an acrylate-based pressure-sensitive adhesive / bonding (PSA) substance or an optically clear adhesive / bonding (OCR) substance.

[0118] 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 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, and a composition containing a black pigment dispersion and / or a black dye can be used as the main constituent, and further contains a resin, a polymerization initiator, and additional additives as needed.

[0119] 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 adhesion surface 710 by a photolithography method.

[0120] The above adhesion surface 710 can be one side on the indoor side of the light-adjusting laminate of the present invention, or can be a separate additional transparent film other than the light-adjusting laminate, but is not limited thereto.

[0121] Dimming laminate 100

[0122] 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 reflected image, which are the main objects of the present invention, can be maximized.

[0123] 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.

[0124] Figures 10a - 10e It is a diagram showing the laminated structure of polarizing plates according to one or more embodiments of the present invention.

[0125] Refer to Figures 10a - 10e , the above 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 10a and Figure 10b ), 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 one surface (refer to Figure 10c) 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 (refer to Figure 10d ) 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 (refer to Figure 10e ).

[0126] 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.

[0127] 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.

[0128] 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 and a dichroic dye, etc.

[0129] 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.

[0130] 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.

[0131] 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. The above dichroic dye can use dichroic dyes 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.

[0132] 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.

[0133] The above protective layer 220 is intended to protect the polarization characteristics of the polarizer 210 from the influence of post - processes and the external environment, and can be realized in the form of a protective film or the like.

[0134] As Figure 10a and Figure 10b As illustrated, the above protective layer 220 can be formed by directly contacting one or both sides of the polarizer 210, but is not limited thereto. For example, the above 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.

[0135] 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).

[0136] As Figure 10c and Figure 10d shown in the figure, the above-mentioned 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 10e shown in the figure, the above-mentioned 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 sequence.

[0137] The above-mentioned 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.

[0138] 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 monomers among the monomers forming the above polymers, etc.

[0139] 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 also be used to dissolve various resin components, and then cast, dried, and cured to form the unstretched film by casting molding.

[0140] 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.

[0141] 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 of the above coating type polarizer.

[0142] 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.

[0143] 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.

[0144] 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 from 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.

[0145] 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.

[0146] 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, and compounds used to form a refractive index adjustment layer in the past or developed in the future can be used. For example, it may be formed from a refractive index adjustment layer forming composition containing a polymerizable isocyanurate compound.

[0147] 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 mechanical durability, an overcoat layer or a hard coat layer may be included.

[0148] 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, an optical laminate with a thin thickness can be manufactured while maintaining the optical characteristics of the polarizing plate 200.

[0149] 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 illustrated in FIG. 1, 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.

[0150] Conventionally, a dimming laminate used for manufacturing a smart window or the like is manufactured by forming a conductive layer for liquid crystal driving on one surface of a substrate and bonding the other surface of the substrate to a polarizing plate. However, the dimming laminate 100 of the present invention is characterized in that a conductive layer is directly formed on one surface of the polarizing plate without including a separate substrate for forming the conductive layer, thereby reducing the thickness of the laminate and improving the transmittance and bending characteristics in the light transmission mode. Further, in the dimming laminate 100 of the present invention, by directly forming a conductive layer on one surface of the polarizing plate, even when a louvered film 700 is further included on the indoor side of the dimming laminate for an antireflection function against a reflected image, the thickness of the variable transmittance optical laminate of the present invention can be reduced and the antireflection function can be imparted without reducing the transmittance adjustment function.

[0151] In one embodiment, the transparent conductive layer 300 may be directly formed by evaporation on one surface of the polarizing plate 200. At this time, in order to improve the adhesion between the transparent conductive layer 300 and the polarizing plate 200, after performing a pretreatment such as a corona treatment or a plasma treatment on one surface of the polarizing plate 200, it can be formed in direct contact with the pretreated surface of the polarizing plate 200. The pretreatment is not limited to the corona treatment or the plasma treatment, and pretreatment processes developed in the past or in the future can be used within the scope that does not damage the purpose of the present invention.

[0152] In another embodiment, in order to improve the adhesion to the polarizing plate 200, the transparent conductive layer 300 may be formed in direct contact with the polarizing plate 200 through an easy-bonding layer (not shown) provided on one surface of the polarizing plate 200.

[0153] 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.

[0154] 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 obtained by mixing metal powder and a curable polymer binder, and the nanowire may be, for example, a silver nanowire (AgNW).

[0155] 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.

[0156] 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.

[0157] 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.

[0158] The above liquid crystal compound is not particularly limited as long as it is driven according to 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 of the reactive liquid crystal compound regarding the above coating type polarizer can be similarly applied.

[0159] 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.

[0160] 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 observed from a 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 relative to the area of the liquid crystal layer 400 is preferably 0.01 to 10%.

[0161] 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.

[0162] 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.

[0163] 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.

[0164] 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, and 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.

[0165] 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 a sealant can be used. The above-mentioned ultraviolet curable resin may be a polymer of an ultraviolet curable monomer. The above-mentioned thermosetting resin may be a polymer of a thermosetting monomer.

[0166] 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 may be an acrylate-based resin, and the above-mentioned acrylate-based resin may be a polymer of an acrylic monomer. The above-mentioned acrylic monomer may 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 may be, for example, a monofunctional acrylate. In this specification, a monofunctional acrylate may refer to a compound having 1 acryloyl group, and a polyfunctional acrylate may 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 object of the present application. The above-mentioned sealant may also contain an initiator as needed, such as a photoinitiator or a thermal initiator.

[0167] 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 by using a dispenser equipped with a nozzle.

[0168] <Smart Windows and Sunroofs>

[0169] 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.

[0170] 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 louver 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 (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 is inclined at a predetermined angle with respect to an adhesion surface in a vertical cross section. 2 . The variable transmittance optical laminate according to claim 1 , wherein a length a of the light shielding pattern obtained by projecting an inclined surface of the light shielding pattern onto the adhesive surface in a vertical cross section is 5 to 50% of the light shielding portion ω1 .

3. 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.

4. 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. 5 . The variable transmittance optical stack according to claim 1 , wherein the light shielding pattern is formed by stacking two or more unit patterns with at least a portion thereof shifted.

6. The variable transmittance optical laminate according to claim 1, wherein the louver film includes a pattern spacing 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 0.5~4.0, and when the spacing between the patterns is set to ω2 and the vertical light-transmitting portion is set to ω3, based on the direction perpendicular to the plane, the opening ratio p defined by ω3 / (ω2+ω1)×100(%) is greater than 70%. The variable transmittance optical stack according to claim 1 , wherein the light shielding pattern protrudes toward a room interior.

8. 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.

9. The variable transmittance optical stack according to claim 8, 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. 10 . The variable transmittance optical laminate according to claim 8 , 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. 11 . The variable transmittance optical laminate according to claim 8 , wherein at least one of the first polarizing plate and the second polarizing plate has a thickness of 30 μm to 200 μm. 12 . The variable transmittance optical stack according to claim 8 , wherein the liquid crystal layer includes one or more spacers selected from the group consisting of spherical spacers and columnar spacers. 13 . The variable transmittance optical laminate according to claim 8 , further comprising alignment films on both surfaces of the liquid crystal layer. 14 . A skylight comprising the variable transmittance optical laminate according to claim 1 .

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