Optical laminate and sunroof comprising the same

Abstract

To provide an optical laminate that provides an anti-reflection function without reducing transmittance of external light and offers advantageous bending characteristics with a small thickness, and to provide a sunroof comprising the same.SOLUTION: The present invention relates to a variable transmittance optical laminate comprising a light control laminate 100 including an electric field-driven liquid crystal provided between polarizing plates, and a louver film 700 provided on at least a portion of the light control laminate on a cabin side. The louver film consists of two or more layers, includes a light shielding pattern, and is placed such that the light shielding pattern faces the cabin side.SELECTED DRAWING: Figure 1a

Description

Technical Field

[0001] The present invention relates to an optical laminate and a sunroof including the same.

Background Art

[0002] Generally, an external light blocking coating is often applied to the glass window of a moving means such as a vehicle. However, the transmittance of the glass window of conventional moving means is fixed, and the transmittance of the external light blocking coating is also fixed. Therefore, the overall transmittance of such a conventional window of a moving means is fixed, which may induce an accident. For example, when the overall transmittance is set low, there is no problem during the daytime when there is sufficient light around. However, in the case of nighttime when the light amount around is not sufficient, there is a problem that it is difficult for a driver or the like to properly check the periphery of the moving means. Or when the overall transmittance is set high, there is a problem that it may cause glare to a driver or the like during the daytime when there is sufficient light around. Thus, a transmittance variable optical laminate capable of changing the light transmittance when a voltage is applied thereto has been developed.

[0003] On the other hand, in a social atmosphere where privacy protection is emphasized, there have been attempts to impart an antireflection function to a glass window. Particularly in the case of a sunroof of a vehicle, when operating at night, there is a problem that the reflected image of the front seat panel reflected by the sunroof causes glare in the field of view of the seated person in the rear seat. Thus, when applying a transmittance variable optical laminate to a sunroof or the like, it is necessary to improve not only the transmittance adjustment function but also the antireflection function for night operation and the like.

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

[0005] However, when a multi-layer coating layer is incorporated to impart such an antireflection function, there are drawbacks that the thickness of the optical laminate increases and the transmittance adjustment performance deteriorates, or the manufacturing process becomes complicated. Further, when such a coating is applied to a laminate that essentially includes a liquid crystal layer and a polarizing plate and includes an electric field-driven liquid crystal between the polarizing plates, the overall thickness of the laminate becomes excessively thick and is not suitable for application to vehicles or buildings.

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

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] 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 in bending characteristics, and a sunroof including the same.

Means for Solving the Problems

[0009] To achieve the above object, the present invention provides a light-adjustable laminate including an electric field-driven liquid crystal between polarizing plates; and a transmittance-variable optical laminate including a louver film disposed on at least a part of the indoor side of the light-adjustable laminate, wherein the louver film is formed by laminating two or more layers, includes a light-shielding pattern, and is disposed such that the light-shielding pattern faces the indoor side.

[0010] In one embodiment of the present invention, the louver film is a laminate of two or more layers, and includes a second adherend surface located on the indoor side and a first adherend surface located between the second adherend surface and the light control laminate. The light shielding pattern of the second adherend surface may protrude toward the indoor side.

[0011] In another embodiment of the present invention, the first adherend surface includes a first light shielding pattern, the second adherend surface includes a second light shielding pattern, and a straight line connecting a point on the outermost contour where the first light shielding pattern contacts the first adherend surface in a vertical cross-section and a corresponding point on the outermost contour where the second light shielding pattern contacts the second adherend surface can form a predetermined inclination angle θ with respect to the first adherend surface by being inclined with respect to the adherend surface.

[0012] In another embodiment of the present invention, the length a of the oblique line connecting a point on the outermost contour where the first light shielding pattern contacts the first adherend surface in a vertical cross-section and a point on the outermost contour of the corresponding second light shielding pattern projected onto the first adherend surface may be 5 to 50% of the length ω1 of the first light shielding pattern.

[0013] In one embodiment of the present invention, the maximum viewing angle θ1 range for the reflected image of the variable transmittance optical laminate may be 40° to 75°, and the viewing angle for the reflected image is the angle of the reflected image with respect to a straight line perpendicular to the indoor side with respect to the adherend surface in the vertical cross-section of the variable transmittance optical laminate.

[0014] In one embodiment of the present invention, the maximum viewing angle θ2 range for the external light transmitted from the outside of the variable transmittance optical laminate may be 60° to 85°, and the viewing angle for the external light is the angle of the external light with respect to a straight line perpendicular to the indoor side with respect to the adherend surface in the vertical cross-section of the variable transmittance optical laminate.

[0015] In one embodiment of the present invention, the louver film may be a variable transmittance optical laminate in which at least two or more adherend surfaces are joined with an adhesive interposed therebetween.

[0016] In one embodiment of the present invention, the louver film includes an interval ω2 between patterns where the light-shielding pattern is not formed on the adherend surface; and a light-shielding portion where the light-shielding pattern is formed on the adherend surface. When the height of the second light-shielding pattern is h2, the shortest straight-line distance between the adherend surfaces is h3, and the length of the first light-shielding pattern is ω1, the value of (h2 + h3) / ω1 may be 0.5 to 4.0, and the aperture ratio p defined by ω3 / (ω2 + ω1)×100 (%) based on the direction perpendicular to the plane may be 70% or more.

[0017] In another embodiment of the present invention, the dimming laminate includes a first polarizing plate, a first transparent conductive layer formed on one surface of the first polarizing plate, a second polarizing plate facing the first polarizing plate, a second transparent conductive layer formed on one surface of the second polarizing plate and facing the first transparent conductive layer, and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer. At least one of the first transparent conductive layer and the second transparent conductive layer may be formed in direct contact with one of the first polarizing plate and the second polarizing plate.

[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 adjustment layer, and a refractive index adjustment 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, an alignment film may be further included on both surfaces of the liquid crystal layer. The present invention provides a sunroof including the variable transmittance optical laminate.

Advantages of the Invention

[0023] According to the optical laminate according to one embodiment of the present invention, it includes a light-shielding pattern protruding toward the indoor side, and the louver film laminated in two or more layers exhibits an excellent antireflection function without reducing the transmittance of external light.

[0024] According to the optical laminate according to one embodiment of the present invention, a transparent conductive layer is formed from a separate substrate and is not attached to the polarizing plate, but a form in which the transparent conductive layer is directly formed on the polarizing plate itself and is in direct contact can be realized, thereby providing an optical laminate with a thin overall thickness and advantageous bending characteristics.

[0025] Also, as described above, when the overall thickness of the optical laminate becomes thin, when applying the louver film having the specific structure of the present invention, it has the advantage of maximizing not only the antireflection function but also the transmittance adjustment function.

[0026] Furthermore, as described above, when the overall thickness of the optical laminate becomes thin, when applying the louver film having the specific structure of the present invention, it is also advantageous to stack a plurality of additional louver films.

[0027] Furthermore, when applying the variable transmittance optical laminate of the present invention as a sunroof, when operating at night, the phenomenon that the reflected image of the front seat panel reflected by the sunroof induces glare in the field of view of the occupants in the rear seats can be improved.

Brief Description of the Drawings

[0028]

Figure 1a

Figure 1b

Figure 2

Figure 3

Figure 4

Figure 5a

Figure 5b

Figure 6a

Figure 6b

Figure 7

Figure 8

Figure 9a

Figure 9b

Figure 9c

Figure 9d

Figure 9e

DETAILED DESCRIPTION OF THE INVENTION

[0029] The present invention not only has a thin thickness and advantageous bending characteristics, but also can effectively adjust the transmittance of external light and has an anti-reflection function. Therefore, when operating at night, the glare induced by the reflected image of the front seat panel reflected by the sunroof in the field of view of the occupants in the rear seat is dramatically improved. The present invention relates to a variable transmittance optical laminate and a smart window and a sunroof including the same.

[0030] More specifically, the main feature of the present invention is that two or more layers of louver films including a light shielding pattern are laminated, and the louver film is arranged such that the light shielding pattern protrudes toward the indoor side, so that the range of the viewing angle θ1 with respect to the reflected image can be adjusted.

[0031] The variable transmittance optical laminate of the present invention is particularly suitable for the technical field in which the light transmissivity can be changed by applying a voltage, and can be used, for example, in a smart window.

[0032] A smart window refers to an optical structure that controls the amount of light or heat transmitted by changing the light transmittance upon the application of an electrical signal. That is, a smart window is provided to be able to change to a transparent, opaque, or translucent state by voltage, and is also called variable transmittance glass, dimming glass, or smart glass.

[0033] Smart windows can be utilized for partitioning the interior spaces of vehicles and buildings or for privacy protection partitions, or may be utilized as daylighting windows arranged at the openings of buildings. They may also be utilized for highway display boards, bulletin boards, scoreboards, clocks, or advertising screens, and can be used to replace the glass of transportation means such as the windows or sunroofs of automobiles, buses, airplanes, ships, or trains.

[0034] Although the variable transmittance optical laminate of the present invention can also be applied to smart windows in the various technical fields described above, since the conductive layer is formed directly on the polarizing plate and does not include a separate substrate for forming the conductive layer, it has a thin thickness and is advantageous in bending characteristics, and can be particularly preferably used for smart windows for vehicles or buildings. In one or more embodiments, a smart window to which the variable transmittance optical laminate of the present invention is applied can be used for transportation means, for example, the front window, rear window, side window, and sunroof window of an automobile, or building fixtures, etc. In addition to the use for blocking external light, it can also be used for partitioning the internal space or protecting privacy inside an automobile or building, such as for 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 transmitted therethrough, but also block the light reflected at adjacent positions, and the privacy protection function is maximized. In particular, when the variable transmittance optical laminate of the present invention is applied to the sunroof of a vehicle, not only is it thin in thickness and advantageous in bending characteristics, but it also has an antireflection function without reducing the transmittance of external light. Therefore, when driving at night, it has the advantage of significantly improving the glare induced by the reflected image of the front seat panel reflected in the sunroof in the field of view of the passengers in the rear seat.

[0035] Hereinafter, embodiments of the present invention will be described more specifically with reference to the drawings. However, the following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the content of the invention described above, serve to better understand 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.

[0036] The terms used in this specification are for the purpose of describing embodiments and are not intended to limit the present invention. In this specification, the singular form also includes the plural form unless otherwise specifically stated in the context. For example, the "polarizing plate" used in this specification may mean at least one polarizing plate of the first polarizing plate and the second polarizing plate, and the "transparent conductive layer" may mean at least one transparent conductive layer of the first transparent conductive layer and the second transparent conductive layer.

[0037] As used in this specification, "comprises" and / or "comprising" are used in a sense that does not preclude the presence or addition of one or more other components, steps, operations and / or elements other than the recited components, steps, operations and / or elements. The same reference numerals throughout the specification refer to the same components.

[0038] Spatially relative terms such as "under", "bottom surface", "lower part", "above", "upper surface", "upper part", etc. can be used to easily describe the correlation between one element or component and another element or component as shown in the drawings. Spatially relative terms should be understood as terms that include different directions of elements relative to each other during use or operation in addition to the directions shown in the drawings. For example, when covering an element shown in the drawings, an element described as "under" or "lower part" of another element may be placed "above" the other element. Therefore, the exemplary term "under" may include both the downward and upward directions. The element can also be oriented in other directions, and thus the spatially relative terms can be interpreted according to the orientation.

[0039] As used herein, the "plane direction" can be interpreted as the direction perpendicular to the polarizing plate and / or the transparent conductive layer, i.e., the direction as viewed from the user's viewing side. Also, the "vertical direction" as used herein may be the thickness direction of the polarizing plate and / or the transparent conductive layer, i.e., the direction perpendicular to the direction as viewed from the user's viewing side with respect to the "plane direction". Further, the "vertical cross-section" can mean the cross-section when the transmissivity variable optical laminate of the present invention is cut in the vertical direction.

[0040] As used herein, the "indoor side" can mean the viewing side of the main user. For example, when the transmissivity variable optical laminate is applied to a vehicle, it can mean the inside of the vehicle, which is the viewing side of the passenger. When the transmissivity variable optical laminate is applied to a building, it can mean the inside of the building, which is the viewing layer of the user inside the building, but is not limited thereto. The "outdoor side" or "outside" is a concept in contrast to the indoor side and can mean the opposite side of the main user's viewing side with respect to the variable optical laminate.

[0041] <Transmissivity variable optical laminate> FIG. 1a and FIG. 1b are diagrams showing the laminated structure of a transmissivity variable optical laminate according to an embodiment of the present invention. (An inclined light-shielding pattern, not shown) The transmissivity variable optical laminate of the present invention includes a dimming laminate 100 containing an electric field-driven liquid crystal between polarizing plates; and a louver film 700 disposed on at least a part of the indoor side of the dimming laminate. In particular, the louver film 700 is laminated with two or more layers, and the louver film 700 includes a light-shielding pattern 720, and the light-shielding pattern 720 is characterized by protruding toward the indoor side.

[0042] The adherend surface of the present invention means the layer to which the light-shielding pattern 720 of the louver film 700 is attached. As an example, when the light-shielding pattern 720 of the louver film 700 of the present invention is directly formed on the light-adjusting laminate 100 without an additional base material or film, the adherend surface may be one surface of the light-adjusting laminate 100, preferably the indoor-side surface of the light-adjusting laminate 100, and may be, for example, a polarizing plate 200, a polarizer 210, a protective layer 220, a laminated retardation layer 230, or a refractive index adjustment layer 240. In another example of the present invention, when the light-shielding pattern 720 of the louver film 700 of the present invention is formed on an additional base material or film such as a transparent film and attached to the light-adjusting laminate, the adherend surface may be an additional base material or film such as a transparent film.

[0043] Louver film 700 FIG. 2 is a diagram showing the structure of a louver film according to an embodiment of the present invention.

[0044] The variable transmittance optical laminate of the present invention includes a louver film 700 disposed on at least a part of the indoor side of the light-adjusting laminate, and the louver film 700 necessarily includes a light-shielding pattern 720.

[0045] The louver film 700 of the present invention may not further include an additional base material or film for supporting the light-shielding pattern 720 in addition to the light-shielding pattern 720. In this case, the light-shielding pattern 720 may be directly formed on one surface of the light-adjusting laminate 100. In this case, the light-shielding pattern 720 is formed on the indoor-side surface of the light-adjusting laminate 100 and is formed to protrude toward the indoor side. The louver film 700 of the present invention can also directly form the light-shielding pattern 720 on the indoor-side surface of the light-adjusting laminate 100. In this case, there is an advantage that the overall thickness of the variable transmittance optical laminate of the present invention can be minimized, and a method of forming a pattern including a separation layer in advance and then transferring it with an adherend surface and an adhesive interposed therebetween can be used. At this time, the thinner the thickness of the adhesive, the thinner the overall thickness of the variable transmittance optical laminate.

[0046] In addition, as shown in Fig. 1b, the louver film 700 of the present invention can further include an additional base material or film for supporting the light-shielding pattern 720, and preferably, can further include a transparent film.

[0047] The louver film 700 is a laminate of two or more layers, and includes a second adhering surface 710-2 located on the indoor side and a first adhering surface 710-1 located between the second adhering surface 710-2 and the light-adjusting laminate. The light-shielding pattern 720-2 of the second adhering surface 710-2 is characterized by protruding toward the indoor side.

[0048] More specifically, the first adhering surface 710-1 includes a first light-shielding pattern 720-1, and the second adhering surface 710-2 includes a second light-shielding pattern 720-2. As shown in Fig. 2, in a vertical cross-section, a straight line connecting a point on the outermost contour where the first light-shielding pattern 720-1 abuts against the first adhering surface 710-1 and a point on the outermost contour where the corresponding second light-shielding pattern 720-2 abuts against the second adhering surface 710-2 can form a predetermined inclination angle θ with respect to the first adhering surface, but is not limited thereto.

[0049] On the other hand, in the present invention, the first light-shielding pattern 720-1 and the corresponding second light-shielding pattern 720-2 are offset from each other on a plane, so that the light-shielding pattern 720 is inclined at a predetermined angle with respect to the adhering surface in a vertical cross-section. The meaning of being inclined in the present invention includes the meaning of being substantially inclined. The meaning of being substantially inclined in the present invention may mean that the overall image of the light-shielding pattern 720 is inclined in the direction facing the user in a vertical cross-section. Hereinafter, in this specification, the "overall image of the light-shielding pattern 720" means the image of the light-shielding pattern formed by a plurality of corresponding light-shielding patterns 720 on the first adhering surface 710-1 and the second adhering surface 710-2. As an example, it may be a trapezoidal image formed by the first light-shielding pattern 720-1 and the corresponding second light-shielding pattern 720-2 shown in Figs. 2 and 4 to 5.

[0050] More specifically, referring to FIG. 2, in the cross-section of the louver film 700 of the present invention, the first adherend surface 710-1 includes an image in which first light-shielding patterns 720-1 having a predetermined height h1 and length ω1 are repeatedly formed at a predetermined interval ω2 on the first adherend surface 710-1, and the second adherend surface 710-2 includes an image in which second light-shielding patterns 720-2 having a predetermined height h2 and length ω4 are repeatedly formed at a predetermined interval ω2 on the second adherend surface 710-2. In FIG. 2, assuming that the first adherend surface 710-1 is placed on the outermost outdoor side and the second adherend surface 710-2 is the adherend substrate on the innermost indoor side, an example is shown where ω1 and ω4 are the same, h1 and h2 are the same, and the intervals between the first light-shielding patterns and the intervals between the second light-shielding patterns are the same. However, it is needless to say that the scope of the present invention is not limited thereto. At this time, by forming the overall image of the light-shielding pattern of the present invention by a plurality of corresponding light-shielding patterns 720 on the first adherend surface 710-1 and the second adherend surface 710-2 to be inclined with respect to the adherend surface, a predetermined vertical light transmission portion ω3 in which a pattern is not formed can be included with respect to the direction perpendicular to the plurality of adherend surfaces.

[0051] More specifically, the fact that the overall image of the light-shielding pattern 720 of the present invention formed by a plurality of light-shielding patterns included in the louver film laminated with two or more layers of the present invention is inclined at a predetermined angle with respect to the adherend surface in a vertical cross-section may mean that the image formed by the plurality of light-shielding patterns due to the lamination of the plurality of adherend surfaces forms an angle that is not perpendicular to the adherend surface.

[0052] More specifically, the light-shielding pattern 720 of the present invention may be inclined in the direction facing the user in a vertical cross-section. As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, the light-shielding pattern 720 may be inclined in the direction facing the occupant of the rear seat. Thereby, it has the advantage of minimizing the transmittance loss of external light with respect to the occupant of the rear seat of the vehicle and dramatically improving the glare induced by the reflected image in the field of view of the occupant of the rear seat.

[0053] The light-shielding pattern 720 attached to the adherend surface 710 may be arranged so as to face the indoor side. In particular, in the case of the light-shielding pattern on the indoor-side adherend surface, as shown in FIG. 2, the second light-shielding pattern 720-2 may protrude toward the indoor side.

[0054] The light-shielding pattern may be any one of a polygon, a circle, a semi-circle, a dotted line type, a straight line type, a slanted line type, a wave type, a serrated type, and a lattice type. As long as the effects of the present application are achieved, the cross-sectional form thereof is not particularly limited.

[0055] The two or more layers of louver films of the present invention are laminated with the shortest straight-line distance h3 between the adherend surfaces, and may be laminated with an adhesive further included between the two or more layers of louver films.

[0056] In the present invention, the corresponding light-shielding patterns of the two or more layers of louver films may be arranged so as to be offset by a predetermined distance in a vertical cross-section.

[0057] More specifically, there is a diagonal projection length a which is the length of the point on the first adherend surface where a diagonal line connecting one point on the outermost contour where the first light-shielding pattern contacts the first adherend surface and one point on the outermost contour of the corresponding second light-shielding pattern in a vertical cross-section is projected onto the first adherend surface. Referring to FIG. 7, it can be said that the diagonal projection length a is obtained by subtracting the vertical light transmission portion ω3 from the interval ω2 between the patterns of the first light-shielding pattern. The a may be 5 to 50% of the length ω1 of the first light-shielding pattern. When the pattern sizes are the same, the smaller the inclination angle θ of the overall image of the light-shielding pattern 720 with respect to the adherend surface with respect to the adherend surface, the longer the diagonal projection length a.

[0058] The variable transmittance optical laminate according to an embodiment of the present invention can adjust the maximum viewing angle θ1 with respect to the reflected image and the maximum viewing angle θ2 with respect to the external light according to the degree of pattern shift determined by not only the image and specifications of the first light-shielding pattern 720-1 and the second light-shielding pattern 720-2, but also the interval ω2 between the patterns, the vertical light transmission portion ω3, the diagonal projection length a, and / or the shortest straight-line distance h3 between adjacent adherend surfaces.

[0059] FIG. 3 is a diagram showing the progress of external light (solid line arrow) and reflected light (dotted line arrow) arriving at the louver film according to one or more embodiments of the present invention.

[0060] In the louver film 700 of the variable transmittance optical laminate of the present invention, among two or more louver films, particularly when the light shielding pattern 720-2 on the adherend surface on the indoor side protrudes toward the indoor side, the reflected light can be blocked by the side surface of the light shielding pattern. Thereby, only the reflected image not blocked by the side surface of the light shielding pattern 720-2 can be visually recognized, and the viewing angle range θ1 of the reflected image can be adjusted.

[0061] Unlike a conventional polarizing panel that incorporates a separate polarizing layer and controls external light by the physical properties within the polarizing layer, that is, the variable transmittance optical laminate of the present invention absorbs light by the physical structure of the light shielding pattern so that the reflected light does not reach the observer.

[0062] Referring to FIG. 3, the louver film 700 of the variable transmittance optical laminate of the present invention is laminated with two or more layers, and the viewing angle range θ2 with respect to the external light transmitted from the outside can be adjusted according to the shortest straight-line distance h3 between the adherend surfaces of the layers to which the light shielding pattern is adhered and the degree of deviation of the light shielding patterns of the respective layers.

[0063] Specifically, in the variable transmittance optical laminate according to an embodiment of the present invention, the range of the angle at which external light passes through the louver film 700 may be determined by the angle formed by a straight line connecting one point on the outermost contour of the first light shielding pattern and the second light shielding pattern with a straight line perpendicular to the adherend surface 710.

[0064] Also, referring to FIG. 3, since part of the reflected light reflected on the indoor side is absorbed by the light shielding pattern depending on the angle, the viewing angle of the reflected light can be adjusted according to the form and size of the light shielding pattern 720.

[0065] Hereinafter, through FIGS. 4 to 6b, the field angle range of the transmissivity variable optical laminate according to an embodiment of the present invention with respect to external light and the field angle range of the reflected light will be described in more detail.

[0066] FIG. 4 is a diagram showing the substantial inclination and its angle formed by the light shielding pattern in the lamination of a plurality of adherend surfaces according to an embodiment of the present invention. At this time, a length of a diagonal line projected onto the first adherend surface by connecting one point on the outermost contour where the first light shielding pattern contacts the first adherend surface and one point on the outermost contour where the corresponding second light shielding pattern contacts the second adherend surface is referred to as a diagonal projection length a.

[0067] Referring to FIG. 4, when the diagonal projection length a is the base of a right triangle and the shortest straight-line distance h3 between the first adherend surface and the second adherend surface is the height of the right triangle, the field angle range of the transmissivity variable optical laminate of the present invention with respect to external light can be adjusted by an inclination angle (hereinafter referred to as theta θ) determined by the degree of deviation of the light shielding pattern of the laminated adherend surfaces.

[0068] The angle formed between the hypotenuse and the base of the right triangle is the angle formed by a line connecting one point on the outermost contour of the first light shielding pattern 720-1 and the second light shielding pattern 720-2 with respect to the horizontal direction of the first adherend surface 710-1 and / or the second adherend surface 710-2, and is the same as the substantial inclination angle formed by the light shielding pattern in the lamination of a plurality of adherend surfaces. By being embodied in a form inclined at a predetermined angle θ in a vertical cross section, the transmittance loss of external light in the inclined direction can be minimized.

[0069] FIG. 5a shows the change in the maximum field angle θ2 with respect to external light due to the degree of deviation of the light shielding pattern depending on the diagonal projection length when the shortest straight-line distance h3 between the first adherend surface and the second adherend surface of the transmissivity variable optical laminate according to an embodiment of the present invention is the same.

[0070] Referring to FIG. 5a, the maximum viewing angle θ2 with respect to external light can be determined according to the degree of deviation between the first light-shielding pattern 720-1 and the second light-shielding pattern 720-2 formed on the first adherend surface 710-1 and the second adherend surface 710-2. At this time, the larger the oblique projection length a increases, the larger the maximum viewing angle θ2 with respect to external light becomes. Thus, in order to adjust the range of the maximum viewing angle θ2 with respect to external light, it is preferable to adjust the oblique projection length a within a predetermined range. When the pattern size is the same, the smaller the angle θ at which the light-shielding pattern is substantially inclined with respect to the adherend surface, the longer the oblique projection length a becomes.

[0071] As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, in order for external light to reach a passenger in the rear seat of the driver's seat of the vehicle who is the observer, the oblique projection length a may be 5 to 50% of the length ω1 of the first light-shielding pattern, but is not limited thereto. In this case, the transmittance of external light with respect to the passenger in the rear seat of the driver's seat of the vehicle can be more efficiently improved.

[0072] FIG. 5b shows the change in the maximum viewing angle θ2 with respect to external light according to the shortest distance between the adherend surfaces when the degree of deviation of the light-shielding pattern is the same due to the oblique projection length of the variable transmittance optical laminate according to an embodiment of the present invention.

[0073] Referring to FIG. 5b, the angle of the maximum viewing angle θ2 with respect to external light can be determined by the shortest straight-line distance h3 between the first adherend surface and the second adherend surface. At this time, the larger the shortest straight-line distance h3 between the adherend surfaces increases, the smaller the maximum viewing angle θ2 with respect to external light becomes. Thus, in order to adjust the range of the maximum viewing angle θ2 with respect to external light, it is preferable to adjust the shortest straight-line distance h3 between the adherend surfaces within a predetermined range.

[0074] As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, in order for external light to reach a passenger in the rear seat of the driver's seat of the vehicle who is the observer, the value of (h2 + h3) / ω1 with respect to the height h2 of the second light-shielding pattern and the length ω1 of the first light-shielding pattern can satisfy, but is not limited to, 0.5 to 4.0. In this case, the transmittance of external light to the passenger in the rear seat of the driver's seat of the vehicle can be more efficiently improved.

[0075] FIG. 6a shows the change in the maximum viewing angle θ1 with respect to the reflected light depending on the degree of deviation of the light-shielding pattern due to the length of the oblique projection when the shortest straight-line distance h3 between the first adherend surface and the second adherend surface of the variable transmittance optical laminate according to an embodiment of the present invention is the same.

[0076] Referring to FIG. 6a, the maximum viewing angle θ1 with respect to the reflected light can be determined according to the degree of deviation between the first light-shielding pattern 720-1 and the second light-shielding pattern 720-2 formed on the first adherend surface 710-1 and the second adherend surface 710-2. At this time, the maximum viewing angle θ1 with respect to the reflected light increases as the length a of the oblique projection increases. Therefore, in order to adjust the range of the maximum viewing angle θ1 with respect to the reflected light, it is preferable to adjust the length a of the oblique projection within a predetermined range.

[0077] As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, in order for the reflected light to reach a passenger in the rear seat of the driver's seat of the vehicle who is the observer, the length a of the oblique projection may be, but is not limited to, 5 to 50% of the length ω1 of the first light-shielding pattern. In this case, the transmittance of the reflected light to the passenger in the rear seat of the driver's seat of the vehicle can be more efficiently improved.

[0078] FIG. 6b shows the change in the maximum viewing angle θ1 with respect to the reflected light depending on the shortest distance between the adherend surfaces when the degree of deviation of the light-shielding pattern due to the length of the oblique projection of the variable transmittance optical laminate according to an embodiment of the present invention is the same.

[0079] Referring to FIG. 6b, the angle of the maximum viewing angle θ1 with respect to the reflected light can be determined by the shortest straight-line distance h3 between the first adhered surface and the second adhered surface. At this time, as the shortest straight-line distance h3 between the adhered surfaces increases, the maximum viewing angle θ1 with respect to the reflected light becomes smaller. Accordingly, in order to adjust the range of the maximum viewing angle θ1 with respect to the reflected light, it is preferable to adjust the shortest straight-line distance h3 between the adhered surfaces within a predetermined range.

[0080] As an example, when the variable transmittance optical laminate of the present invention is applied to a sunroof of a vehicle, in order for the reflected light to reach the occupant of the rear seat of the driver's seat of the vehicle, which is the observer, the value of (h2 + h3) / ω1 with respect to the height h2 of the second light-shielding pattern and the length ω1 of the first light-shielding pattern can satisfy, but is not limited to, 0.5 to 4.0. In this case, the transmittance of the reflected light to the occupant of the rear seat of the driver's seat of the vehicle can be more efficiently improved.

[0081] Referring to FIG. 7 showing an example, when the length ω1 of the first light-shielding pattern is the same, the variable transmittance optical laminate of the present invention can adjust the viewing angle range θ1 with respect to the reflected image and the viewing angle range θ2 with respect to the external light by the interval ω2 between the patterns, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adhered surfaces, and / or the length a of the oblique projection. As an example, when the length ω1 of the first light-shielding pattern is the same, the smaller the interval ω2 between the patterns and / or the larger h2 to h3, the smaller the maximum viewing angle θ1 with respect to the reflected image. Also, when the length ω1 of the first light-shielding pattern is the same, the smaller the interval ω2 between the patterns and / or the larger h2 to h3 of the light-shielding pattern, the smaller the maximum viewing angle θ2 with respect to the external light.

[0082] Also, with respect to the value obtained by combining the height h2 of the second light-shielding pattern and the shortest straight-line distance h3 to the adherend surface, and the length ω1 of the first light-shielding pattern, (h2 + h3) / ω1 can satisfy 0.5 to 4.0. With respect to the interval ω2 between the patterns and the vertical light-transmitting portion ω3, the aperture ratio p defined by ω3 / (ω2 + ω1)×100 (%) based on the direction perpendicular to the plane may be 70% or more. At this time, the range of each value is specified by a relationship that satisfies all of h2, h3, ω1, and p, whereby the pattern image can be determined.

[0083] When the aperture ratio p of the louver film 700 of the present invention in the planar direction is 70% or more, there is an advantage that the antireflection performance on the surface of the light control laminate can be ensured and the transmittance can be maintained high in the transmission mode of the light control laminate. Generally, when the aperture ratio p of the louver film 700 is low, the transmittance deteriorates. However, in the case of the present application, since the light-shielding pattern is inclined at a predetermined angle with respect to the adherend surface in the vertical cross-section, when 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.

[0084] In the present invention, as described above, the length ω1 of the first light-shielding pattern of the light-shielding pattern, the interval ω2 between the patterns, the height h1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adherend surfaces, and the maximum viewing angle θ1 with respect to the reflected image and the maximum viewing angle θ2 with respect to external light set by the oblique projection length a, when considered together with the distance from the transmissivity variable optical laminate of the present invention to the main user located on the indoor side and / or the line-of-sight height of the main user, the antireflection function and the external light transmission function for an arbitrary image on the indoor side can be maximized more precisely.

[0085] FIG. 8 is a diagram showing an example of the variable transmittance optical laminate. Referring to FIG. 8 in which the dimming laminate of the present invention is applied to a sunroof of a vehicle, the range that determines the visual field range of the seated person of the main user is ΔD. In the ΔD, the distance to the end point of the ΔD value range is the distance D2 from the point where the maximum viewing angle with respect to external light reaches the line of sight of the main user to the ceiling, and the distance to the start point of the ΔD value range is the distance D1 from the point where the maximum viewing angle with respect to reflected light reaches the line of sight of the main user to the ceiling.

[0086] In an example of the present invention, when setting the maximum viewing angle θ1 with respect to the reflected image and the maximum viewing angle θ2 with respect to external light so that the line-of-sight position of the main user located on the indoor side from the variable transmittance optical laminate of the present invention deviates from the maximum viewing angle θ1 with respect to the reflected image and is included within the range of the maximum viewing angle θ2 with respect to external light, the antireflection function and the external light transmission function for any image on the indoor side can be maximized. Thus, the maximum viewing angle θ1 with respect to the reflected image and the maximum viewing angle θ2 with respect to external light of the present invention may be set such that the line-of-sight position of the main user located on the indoor side from the variable transmittance optical laminate of the present invention deviates from the maximum viewing angle θ1 with respect to the reflected image and is included within the range of the maximum viewing angle θ2 with respect to external light, and the length ω1 of the first light-shielding pattern, the interval ω2 between the patterns, the height h1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adherend surfaces, and / or the oblique projection length a of the louver film of the present invention may be set to achieve such a viewing angle range.

[0087] More specifically, for the variable transmittance optical laminate having an arbitrary light-shielding pattern, the light emitted from the front seat panel of the vehicle forms the maximum viewing angle θ1 with respect to the reflected image in the visual field of the seated person, and the external light forms the maximum viewing angle θ2 with respect to the external light in the visual field of the seated person and arrives.

[0088] As an example of the present invention, the range θ1 of the maximum viewing angle with respect to the reflected image may be 40° to 75°, and the viewing angle θ1 with respect to the reflected image is the angle of the reflected image with respect to the straight line perpendicular to the adherend surface on the indoor side in the vertical cross section of the variable transmittance optical laminate.

[0089] As an example of the present invention, the range of the maximum viewing angle θ2 with respect to external light transmitted from the outside may be 60° to 85°, and the viewing angle θ2 with respect to the external light is the angle of the external light with respect to a straight line perpendicular to the indoor side with respect to the adherend surface in the vertical cross-section of the transmissivity variable optical laminate.

[0090] In an example of the present invention, when the light control laminate of the present invention is applied to a sunroof of a vehicle, in order not to reduce the transmissivity of external light without inducing glare in the field of view of the occupant in the rear seat for the indoor side reflection image such as the front seat panel, the range of the field of view of the occupant in the rear seat is important. Therefore, the range where the field of view of the occupant in the rear seat is located must be adjusted so as to include the viewing angle range θ2 with respect to the external light and not to include the viewing angle range θ1 with respect to the reflection image.

[0091] The proper curvature range of the transmissivity variable optical laminate applied to the vehicle can be varied depending on the height of the vehicle body, the seat height of the occupant, etc., and may be affected by the ceiling height. The ceiling height means the vertical distance from the eye height of the occupant in the rear seat to the innermost surface on the indoor side of the ceiling, and specifically, it can satisfy 300 mm to 600 mm, preferably 300 mm to 500 mm.

[0092] Hereinafter, with reference to FIG. 8, the height h1 of the first light shielding pattern, the height h2 of the second light shielding pattern, the shortest straight line distance h3 between the adherend surfaces, and the oblique projection length a will be described in more detail so as not to reduce the transmissivity of external light without inducing glare in the field of view of the occupant in the rear seat for the reflection image of the front seat panel.

[0093] FIG. 8 is a diagram showing a reflected image (dotted arrow) that starts from the front seat panel and reaches the field of view of the seated person, and external light (solid arrow) that is transmitted outside and reaches the field of view of the seated person. For example, the interval ω2 between patterns where no light-shielding pattern is formed on the louver film, the straight-line distance L' from a point where the light starting from the front seat panel reaches the transmissivity-variable optical laminate to the ceiling of the seated person in the rear seat, the distance D2 from the point where the external light reaches the field of view of the seated person in the rear seat to the ceiling of the seated person in the rear seat, and the distance D1 from the point where the reflected light reaches the field of view of the seated person in the rear seat to the ceiling of the seated person in the rear seat, the D1 - D2 value means ΔD. The ΔD value is the range of the field of view of the seated person in the rear seat where the reflected image of the front seat panel does not induce glare in the field of view of the seated person in the rear seat and does not reduce the transmissivity of the external light, and the field of view of the seated person in the rear seat can be located within the range of ΔD.

[0094] The ΔD value is the range of the subject's field of view where the reflected image does not induce glare in the subject's field of view and does not reduce the transmissivity of the external light. Specifically, when the position of the eyes is within the ΔD range, only the external light is visible without the reflected light being visible, and when outside the ΔD range, not only the external light but also the reflected light is visible. As an example, assuming that the transmissivity-variable optical laminate of the present invention is applied to the sunroof of a vehicle, it is preferable that the range of 300 mm to 500 mm, which is the vertical distance from the eye height of the seated person in the rear seat to the innermost surface on the indoor side of the ceiling (transmissivity-variable optical laminate), overlaps with the ΔD value range.

[0095] The ΔD value can be determined according to the length ω1 of the first light-shielding pattern of the light-shielding pattern, the interval ω2 between the patterns, the height h1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, the shortest straight-line distance h3 between the adherend surfaces, and the inclined surface projection length a. Specifically, the viewing angle θ1 with respect to the reflected image is tan^(-1)(ω2 / (2h2 + 2h3)), the viewing angle θ2 with respect to the external light is tan^(-1)((ω2 + a) / (h2 + h3)), the distance D1 from the point where the reflected light reaches the field of view of the occupant in the rear seat to the ceiling of the occupant in the rear seat is L’ / tan(θ1), and the distance D2 from the point where the external light reaches the field of view of the occupant in the rear seat to the ceiling of the occupant in the rear seat is (L’ + ω2 / 2 + a) / tan(θ2). Therefore, the viewing angles θ1 and θ2 are adjusted by the sum of the length ω1 of the first light-shielding pattern, the height h2 of the second light-shielding pattern, and the shortest straight-line distance h3 between the adherend surfaces. The values of D1 and D2 are adjusted by the values of θ1, θ2, the interval ω2 between the patterns, and the inclined surface projection length a, and the ΔD range value is determined.

[0096] Also, the larger the value of θ2 and the smaller the value of θ1, the larger the range of ΔD. Preferably, D2 may be 500 mm or less, and D2 + ΔD may be 300 mm or more.

[0097] At this time, when the inclined surface projection length a increases, it may cause an aperture ratio loss. However, since the θ1 value decreases and the end point of ΔD becomes farther from the upper transmissivity variable optical laminate, the range of ΔD can be widened.

[0098] In an example of the present invention, the louver film 700 includes a light-shielding pattern 720. The light-shielding pattern 720 may be directly formed on the dimming laminate, or may be formed on a separate transparent film and adhered to the dimming laminate. When the light-shielding pattern 720 is formed on the transparent film, an adhesive layer (not shown for convenience) may further be included between the transparent film and the dimming laminate. As an example, a structure including a first light-shielding pattern directly formed on the dimming laminate, an adhesive layer formed on the first light-shielding pattern, and a transparent film having a second light-shielding pattern formed on the adhesive layer may be included.

[0099] The transparent film may use a conventional or later-developed film. The material of the transparent film layer used in manufacturing the louver film 700 used in the present invention, when manufactured in film form, can be any known synthetic resin or natural resin that exhibits a predetermined light transmittance. Synthetic resins are preferred from the viewpoints of economy and processability. Examples of resins that can be used for the material of the transparent film layer include polyvinyl chloride (PVC), polyethylene terephthalate (PET), polyacrylate, polymethyl methacrylate, polyurethane, polycarbonate, polyethylene, polypropylene, cellulose acetate butyrate (CAB), or copolymers thereof.

[0100] The louver film 700 includes a light-shielding pattern 720 and may further include an adhesive layer (not shown for convenience) between the adherend surface and the light-shielding pattern.

[0101] The adhesive layer (not shown for convenience) can be formed using an adhesive and preferably has excellent heat-resistant adhesiveness. The heat-resistant adhesiveness means that the adhesion change rate after being put into an 80°C oven for 240 hours is 30% or less or no bubbles are generated as compared with the adhesion before being put into the oven.

[0102] The above-mentioned adhesive can use conventional or later-developed adhesives. In one or more embodiments, acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, polyvinyl alcohol adhesives, polyvinyl pyrrolidone adhesives, polyacrylamide adhesives, cellulose adhesives, vinyl alkyl ether adhesives, etc. can be used. The adhesive is not particularly limited as long as it has adhesive force and viscoelasticity. However, from the perspective of easy availability, etc., it may preferably be an acrylic adhesive, for example, it may contain a (meth)acrylate copolymer, a crosslinking agent, a solvent, etc. Also, it may be selected in consideration of the adhesion characteristics to the light-shielding pattern 720 and ensuring viscoelasticity. For example, the adhesive layer can contain an acrylate-based pressure-sensitive adhesive (PSA) substance or an optically clear adhesive (OCR) substance.

[0103] The above-mentioned light-shielding pattern 720 can be applied without being restricted by the materials used for light-shielding purposes. For example, it may be manufactured containing a light-shielding agent, a light diffusing and / or coloring agent. In one embodiment of the present invention, the light-shielding pattern of the present invention can be manufactured by applying a composition containing a black coloring material, and using a composition containing a black pigment dispersion and / or a black dye as the main constituent, and optionally, it can further contain a resin, a polymerization initiator, and additional additives.

[0104] The method for forming the above-mentioned light-shielding pattern 720 is not particularly limited. As an example, a method of making grooves in a transparent film and filling it with the material for forming the light-shielding pattern 720; or a method of manufacturing a photosensitive resin composition for forming the light-shielding pattern 720 and forming the light-shielding pattern 720 on the transparent film by a photolithography method can be applied.

[0105] The adherend surface 710 may be one side on the indoor side of the light-adjusting laminate of the present invention, or it may be a transparent film separately added in addition to the light-adjusting laminate, but it is not limited thereto.

[0106] Dimming laminate 100 The dimming laminate of the present invention includes an electric field-driven liquid crystal between polarizing plates, and in particular, has a structure in which a transparent conductive layer is in direct contact with a polarizing plate. As a result, the thickness of the dimming laminate and the transmissivity variable optical laminate including the same is reduced, and not only has advantages in manufacturing processes and applications, but in particular, the viewing angle adjustment characteristics and transmissivity adjustment characteristics with respect to the main object of the present invention, the reflected image, can be maximized.

[0107] Specifically, the dimming laminate of the present invention includes a first polarizing plate, a first transparent conductive layer formed on one surface of the first polarizing plate, a second polarizing plate facing the first polarizing plate, a second transparent conductive layer formed on one surface of the second polarizing plate and facing the first transparent conductive layer, 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.

[0108] FIG. 9 is a diagram showing a laminated structure of polarizing plates according to one or more embodiments of the present invention. Referring to FIG. 9, the polarizing plate 200 may include a polarizer 210, and may further include functional layers such as a protective layer 220, a retardation adjustment layer 230, and a refractive index adjustment layer 240 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 (see FIGS. 9a and 9b), 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 facing the one surface of the polarizer 210 (see FIG. 9c), a polarizer 210, a protective layer 220 laminated on one surface of the polarizer, a retardation adjustment layer 230 and a refractive index adjustment layer 240 laminated in sequence on the other surface facing the one surface of the polarizer 210 (see FIG. 9d), or a polarizer 210, a protective layer 220 laminated on one surface of the polarizer, and a protective layer 220 and a retardation adjustment layer 230 laminated in sequence on the other surface facing the one surface of the polarizer 210 (see FIG. 9e).

[0109] As the polarizer 210, a conventional or later-developed polarizer can be used. For example, a stretched polarizer or a coating polarizer can be used.

[0110] In one embodiment, the stretched polarizer may include a stretched polyvinyl alcohol (PVA) - based resin. The polyvinyl alcohol (PVA) - based resin may be a polyvinyl alcohol - based resin obtained by saponifying a polyvinyl acetate - based resin. Examples of the polyvinyl acetate - based resin include polyvinyl acetate which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. Examples of the other monomers may include unsaturated carboxylic acid - based, unsaturated sulfonic acid - based, olefin - based, vinyl ether - based, acrylamide - based monomers having an ammonium group, etc. The polyvinyl alcohol (PVA) - based resin also includes modified ones, for example, polyvinyl formal or polyvinyl acetal modified with aldehydes.

[0111] In one embodiment, the coated polarizer may be formed of a liquid crystal coating composition. At this time, the liquid crystal coating composition may contain a reactive liquid crystal compound, a dichroic dye, and the like.

[0112] The reactive liquid crystal compound can mean a compound containing, for example, a mesogen skeleton and further containing one or more polymerizable functional groups. Such reactive liquid crystal compounds are variously known under the name of so-called RM (Reactive Mesogen). The reactive liquid crystal compound can form a cured film in which a polymer network is formed while being polymerized by light or heat to maintain a liquid crystal alignment.

[0113] The reactive liquid crystal compound may be a monofunctional or polyfunctional reactive liquid crystal compound. The monofunctional reactive liquid crystal compound is a compound having one polymerizable functional group, and the polyfunctional reactive liquid crystal compound can mean a compound containing two or more polymerizable functional groups.

[0114] The dichroic dye is a component contained in the liquid crystal coating composition and imparts 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 dichroic dye may be a conventional or newly developed dichroic dye, and may contain, for example, one or more selected from the group consisting of azo dyes, anthraquinone dyes, perylene dyes, merocyanine dyes, azomethine dyes, phthaloperylene dyes, indigo dyes, dioxazine dyes, polythiophene dyes, and phenoxazine dyes.

[0115] The composition for liquid crystal coating may further contain a solvent capable of dissolving the reactive liquid crystal compound and the dichroic dye. For example, propylene glycol monomethyl ether acetate (PGMEA), methyl ethyl ketone (MEK), xylene, chloroform, etc. may be used. Further, the composition for liquid crystal coating may further contain a leveling agent, a polymerization initiator, etc. within a range that does not impair the polarization characteristics of the coating film.

[0116] The protective layer 220 is for preserving the polarization characteristics of the polarizer 210 from subsequent processes and the external environment, and can be embodied in the form of a protective film or the like.

[0117] As shown in FIGS. 9a and 9b, the 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 protective layer may be used as a multilayer structure in which one or more protective layers are continuously laminated, or may be formed in direct contact with other functional layers.

[0118] In one or more embodiments, the 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).

[0119] The retardation adjusting layer 230 may be formed in direct contact on one surface of the polarizer 210 as shown in FIGS. 9c and 9d, but is not limited thereto. For example, as shown in FIG. 9e, the retardation adjusting layer 230 may be formed on one surface of the protective layer 220, and the polarizer 210, the protective layer 220, and the retardation adjusting layer 230 may be sequentially laminated.

[0120] The retardation adjusting layer 230 may use a polymer stretched film obtained by stretching a polymer film capable of imparting optical anisotropy by stretching in an appropriate manner, or a liquid crystal polymer film.

[0121] In one embodiment, the polymer stretched film may use a polymer layer including 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 polymer.

[0122] The method for obtaining the polymer stretched film is not particularly limited. For example, it can be obtained by stretching the 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, and cast molding. Secondary processing molding methods such as pressure air molding and vacuum molding may also be used. Among them, extrusion molding and cast molding are preferably used. At this time, for example, an unstretched film can be extrusion molded using an extruder equipped with a T-die, a circular die, etc. When obtaining a molded product by extrusion molding, a material obtained by previously melt-kneading various resin components, additives, etc. can be used, or it can also be molded through melt-kneading during extrusion molding. Further, after dissolving various resin components using a solvent common to various resin components, such as a solvent such as chloroform or methylene dichloride, an unstretched film may be cast molded by cast drying and solidifying.

[0123] The polymer stretched film may be uniaxially stretched in the machine flow direction (MD; Mechanical Direction, longitudinal direction or length direction) of the formed film, uniaxially stretched in the direction transverse to the machine flow direction (TD; Transverse Direction, transverse direction or width direction), or a biaxially stretched film may be manufactured by stretching by a sequential biaxial stretching method of roll stretching and tenter stretching, a simultaneous biaxial stretching method by tenter stretching, a biaxial stretching method by tubular stretching, etc.

[0124] The liquid crystal polymer film can contain the reactive liquid crystal compound in a polymerized state. The content regarding the reactive liquid crystal compound of the coating type polarizer described above can be similarly applied to the reactive liquid crystal compound.

[0125] In one or more embodiments, the thickness of the retardation adjustment 230 layer may be 10 to 100 μm in the case of a polymer stretched film, and may be 0.1 to 5 μm in the case of a liquid crystal polymer film.

[0126] The refractive index adjustment layer 240 is provided to compensate for the refractive index difference of the optical laminate due to the transparent conductive layer 300, and may serve to improve visual recognition characteristics or the like by reducing the refractive index difference. Further, the refractive index adjustment layer 240 may be provided to correct the hue caused by the transparent conductive layer 300. On the other hand, when the transparent conductive layer has a pattern, the transmittance difference between the pattern region where the pattern is formed and the non-pattern region where the pattern is not formed can be compensated through the refractive index adjustment layer 240.

[0127] Specifically, the transparent conductive layer 300 is laminated adjacent to another member (for example, a polarizer or the like) having a different refractive index from it, and a difference in light transmittance may be induced by the refractive index difference with the adjacent other layer. In particular, when a pattern is formed on the transparent conductive layer, a problem may occur in that it can be visually recognized so as to distinguish between the pattern region and the non-pattern region. Therefore, by including the refractive index adjustment layer 240, the refractive index is compensated so that the difference in light transmittance of the optical laminate can be reduced. In particular, when a pattern is formed on the transparent conductive layer, the pattern region and the non-pattern region are not distinguished and not visually recognized.

[0128] In one embodiment, the refractive index of the refractive index adjustment layer 240 may be appropriately selected depending on the material of another adjacent member, but is preferably 1.4 to 2.6, and more preferably may be 1.4 to 2.4. In this case, light loss due to a sharp refractive index difference between the transparent conductive layer 300 and another member such as the polarizer 210 can be prevented.

[0129] The refractive index adjustment layer 240 is not particularly limited as long as it can prevent a sharp refractive index difference between the transparent conductive layer 300 and another member such as the polarizer 210, and a compound used for forming a conventional or later-developed refractive index adjustment layer may be used. For example, it may be formed from a refractive index adjustment layer forming composition containing a polymerizable isocyanurate compound.

[0130] In one embodiment, the polarizing plate 200 may further include other configurations for assisting or enhancing the characteristics of the polarizer in addition to the above-described components. For example, in order to further improve mechanical durability, it may further include an overcoat layer or the like.

[0131] In one or more embodiments, the polarizing plate 200 may have a thickness of 30 to 200 μm, preferably 30 to 170 μm, and more preferably 50 to 150 μm. In this case, the polarizing plate 200 can be used to manufacture an optical laminate with a thin thickness while maintaining optical properties.

[0132] The transparent conductive layer 300 is provided for driving the liquid crystal layer 400 and may be formed in direct contact with the polarizing plate 200. For example, as shown in FIG. 1, the first transparent conductive layer 300-1 and the second transparent conductive layer 300-2 may be formed in direct contact with the first polarizing plate 200-1 and the second polarizing plate 200-2, respectively.

[0133] Optical laminates used in the manufacture of conventional smart windows and the like are 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 light control laminate 100 according to the present invention directly forms a conductive layer on one surface of a 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, when the light control laminate 100 according to the present invention further includes a louver film 700 on the indoor side of the light control laminate for an antireflection function with respect to a reflected image by directly forming a conductive layer on one surface of the polarizing plate, the thickness of the variable transmittance optical laminate of the present invention can be reduced, and an antireflection function can be imparted without reducing the light transmittance adjustment function.

[0134] In one embodiment, the transparent conductive layer 300 may be formed by directly depositing on one surface of the polarizing plate 200. At this time, for improving the adhesion between the transparent conductive layer 300 and the polarizing plate 200, after performing a pretreatment such as corona treatment or plasma treatment on one surface of the polarizing plate 200, it may be formed by directly contacting the pretreated surface of the polarizing plate 200. The pretreatment is not limited to corona treatment or plasma treatment, and pretreatment processes that are conventional or developed later may be used within the scope that does not impair the object of the present invention.

[0135] In another embodiment, for improving the adhesion between the transparent conductive layer 300 and the polarizing plate 200, it may be formed by directly contacting the polarizing plate 200 with an easy-adhesion layer (not shown) provided on one surface of the polarizing plate 200 interposed therebetween.

[0136] The transparent conductive layer 300 preferably has a transmittance of 50% or more with respect to visible light. For example, it may include one or more selected from the group consisting of transparent conductive oxides, metals, carbon-based substances, conductive polymers, conductive inks, and nanowires, but is not limited thereto, and materials of conventional or later-developed transparent conductive layers may be used.

[0137] In one or more embodiments, the transparent conductive oxide may include one or more selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), fluorine tin oxide (FTO), and zinc oxide (ZnO). Further, the metal may include one or more selected from the group consisting of gold (Au), silver (Ag), copper (Cu), aluminum (Al), platinum (Pt), palladium (Pd), chromium (Cr), titanium (Ti), tungsten (W), niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), and alloys containing at least one of these, for example, it may include a silver - palladium - copper (APC) alloy or a copper - calcium (CuCa) alloy. The carbon - based material may include one or more selected from the group consisting of carbon nanotubes (CNT) and graphene. The conductive polymer may include one or more selected from the group consisting of polypyrrole, polythiophene, polyacetylene, PEDOT, and polyaniline. The conductive ink may be an ink in which a metal powder and a curable polymer binder are mixed, and the nanowire may be, for example, a silver nanowire (AgNW).

[0138] Further, the transparent conductive layer 300 may be formed in a structure of two or more layers by combining the substances. For example, it may be formed in a two - layer structure including a metal layer and a transparent conductive oxide layer so as to reduce the reflectance of incident light and increase the transmittance.

[0139] The liquid crystal layer 400 can change the driving mode of the optical laminate by adjusting the transmittance of light incident from one or more directions by an electric field.

[0140] The liquid crystal layer 400 may include a liquid crystal compound and a spacer. For example, as shown in FIG. 1b, it may mean a region defined by a first alignment film 500-1, a second alignment film 500-2, and a sealant 600.

[0141] The liquid crystal compound is driven by an electric field and is not particularly limited as long as it can control the light transmittance. Conventional or later-developed liquid crystal compounds can be used. For example, the content related to the reactive liquid crystal compound of the coating type polarizer described above can be similarly applied.

[0142] The liquid crystal behavior mode of the liquid crystal compound 400 is not particularly limited. For example, as shown in FIG. 1b, it may be driven in a TN (Twisted nematic) mode, but it is not limited thereto, and it may be driven in an STN (Super twisted nematic) mode, a VA (Vertical alignment) mode, an ECB (Electrically controlled birefringence) mode, etc.

[0143] The spacer may include at least one or more spacers among a ball spacer and a column spacer, and a ball spacer is particularly preferred. The spacer may be one or more, and preferably has a height of 1 μm to 10 μm. Also, when viewed from the planar direction, the area occupied by the spacer in the liquid crystal layer 400 is preferably 0.01 to 10% of the area of the liquid crystal layer 400 from the viewpoints of user visibility and improvement of transmittance in the light transmission mode.

[0144] In one embodiment, the liquid crystal layer 400 may further include an alignment film 500 as needed, for example, it may be formed on both surfaces of the liquid crystal layer 400 containing a liquid crystal compound.

[0145] The alignment film 500 is not particularly limited as long as it can impart alignment properties to the dispersed liquid crystal, and preferably, it may contain a photo-aligning or photocurable polymer or the like. For example, the alignment film 500 can be produced by applying and curing an alignment film coating composition containing a photo-aligning or photocurable polymer, a photoinitiator, and a solvent.

[0146] The photo-aligning or photocurable polymer is not particularly limited, and a cinnamate-based polymer, a polyimide-based polymer, or the like may be used. For example, poly(vinyl cinnamate) (PVCi), poly(siloxane cinnamate) (PSCN), poly(ω(4-chalconyloxy)alkoxyphenylmaleimide, 6-FDA-HAB-Cl, or the like may be used, and a polymer that can exhibit alignment properties, whether conventional or developed in the future, may also be used.

[0147] The sealant 600 is located between the first polarizing plate 200-1 and the second polarizing plate 200-2 in the non-active region, serves to bond the first polarizing plate and the second polarizing plate, and may be provided to secure a space for providing the liquid crystal layer 400 between the first polarizing plate 200-1 and the second polarizing plate 200-2 together with the spacer.

[0148] The sealant 600 may contain a curable resin as a base resin. As the base resin, an ultraviolet curable resin or a thermosetting resin known to be used in sealants in the art may be used. The ultraviolet curable resin may be a polymer of an ultraviolet curable monomer. The thermosetting resin may be a polymer of a thermosetting monomer.

[0149] As the base resin of the sealant 600, for example, an acrylate resin, an epoxy resin, a urethane resin, a phenol resin, or a mixture of the resins may be used. In one embodiment, the base resin may be an acrylate resin, and the acrylate resin may be a polymer of an acrylic monomer. The acrylic monomer may be, for example, a polyfunctional acrylate. In other embodiments, the sealant may further contain a monomer component in the base resin. The monomer component may be, for example, a monofunctional acrylate. In this specification, the monofunctional acrylate can mean a compound having one acrylic group, and the polyfunctional acrylate can mean a compound having two or more acrylic groups. The curable resin can be cured by irradiation with ultraviolet rays and / or heating. The ultraviolet irradiation conditions or heating conditions may be appropriately carried out within a range that does not impair the object of the present application. The sealant may further contain an initiator, for example, a photoinitiator or a thermal initiator, if necessary.

[0150] The sealant 600 may be formed by a method commonly used in the art. For example, it may be formed by drawing the sealant onto the outer contour (i.e., the inactive region) of the liquid crystal layer using a dispenser equipped with a nozzle.

[0151] <Smart Window and Sunroof> In addition to the variable transmittance optical laminate, the present invention includes a smart window containing the same. Further, the present invention includes an automobile in which the smart window is applied to at least one of a front window, a rear window, a side window, a sunroof window, and an interior partition, and a building fixture for a building containing the smart window.

[0152] For example, an automobile including the smart window of the present invention may bond vehicle glass onto both surfaces of a variable transmittance optical laminate, and the vehicle glass may include the above-described louver film. For example, the smart window including the vehicle glass may be manufactured by placing an adhesive film and vehicle glass on both surfaces of the optical laminate and then heating them at a temperature of 90°C and in a vacuum state of about 1 bar for 10 to 20 minutes using a press machine. The adhesive film may include an EVA film, a PVB film, or the like.

Explanation of Reference Numerals

[0153] 100: Light control laminate 200: Polarizing plate 210: Polarizer 220: Protective layer 230: Retardation adjustment layer 240: Refractive index adjustment layer 300: Transparent conductive layer 400: Liquid crystal layer 500: Alignment film 600: Sealant 700: Louver film 700-1: First louver film 700-2: Second louver film 710: Adhesive surface 710-1: First adhesive surface 710-2: Second adhesive surface 720: Light shielding pattern 720-1: First light shielding pattern 720-2: Second light shielding pattern

Claims

1. A dimming laminate including an electric field-driven liquid crystal between polarizing plates; and A variable transmittance optical laminate including a louver film disposed on at least a part of the indoor side of the dimming laminate, The louver film is laminated with two or more layers, includes a light-shielding pattern, A variable transmittance optical laminate in which the light-shielding pattern is arranged to face the indoor side.

2. The louver film Includes a second adhering surface located on the indoor side and a first adhering surface located between the second adhering surface and the dimming laminate, The light-shielding pattern on the second adhering surface protrudes toward the indoor side. The variable transmittance optical laminate according to claim 1.

3. The first adhering surface includes a first light-shielding pattern, The second adhering surface includes a second light-shielding pattern, A straight line connecting a point on the outermost contour where the first light-shielding pattern contacts the first adhering surface and a point on the outermost contour where the corresponding second light-shielding pattern contacts the second adhering surface in a vertical cross-section forms a predetermined inclination angle θ with the adhering surface with an oblique line with respect to the first adhering surface. The variable transmittance optical laminate according to claim 2.

4. The length a of the oblique line connecting a point on the outermost contour where the first light-shielding pattern contacts the first adhering surface and a point on the outermost contour of the corresponding second light-shielding pattern projected onto the first adhering surface in a vertical cross-section is 5 to 50% of the length ω1 of the first light-shielding pattern. The variable transmittance optical laminate according to claim 3.

5. The variable transmittance optical laminate has a maximum viewing angle θ1 range for the reflected image of 40° to 75°, and the viewing angle for the reflected image is the angle of the reflected image with respect to a straight line perpendicular to the indoor side with respect to the adhering surface in the vertical cross-section of the variable transmittance optical laminate. The variable transmittance optical laminate according to claim 1.

6. The variable transmittance optical laminate has a maximum viewing angle θ2 range for external light transmitted from the outside of 60° to 85°, and the viewing angle for the external light is the angle of the external light with respect to a straight line perpendicular to the indoor side with respect to the adhering surface in the vertical cross-section of the variable transmittance optical laminate. The variable transmittance optical laminate according to claim 1.

7. The louver film has at least two or more adhering surfaces joined with an adhesive interposed therebetween. The variable transmittance optical laminate according to claim 1.

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

9. The dimming laminate a first polarizing plate, a first transparent conductive layer formed on one surface of the first polarizing plate, a second polarizing plate facing the first polarizing plate, a second transparent conductive layer formed on one surface of the second polarizing plate and facing the first transparent conductive layer, and includes a dimming laminate including 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. The variable transmittance optical laminate according to claim 1.

10. At least one of the first transparent conductive layer and the second transparent conductive layer includes one or more selected from the group consisting of transparent conductive oxides, metals, carbon-based substances, conductive polymers, conductive inks, and nanowires. The variable transmittance optical laminate according to claim 9.

11. At least one of the first polarizing plate and the second polarizing plate includes one or more functional layers selected from the group consisting of a protective layer, a retardation adjustment layer, and a refractive index adjustment layer. The variable transmittance optical laminate according to claim 9.

12. At least one of the first polarizing plate and the second polarizing plate has a thickness of 30 μm to 200 μm. The variable transmittance optical laminate according to claim 9.

13. The liquid crystal layer includes one or more spacers selected from the group consisting of a ball spacer and a column spacer. The variable transmittance optical laminate according to claim 9.

14. The variable transmittance optical laminate according to claim 9, further including alignment films on both surfaces of the liquid crystal layer.

15. A sunroof including the variable transmittance optical laminate according to any one of claims 1 to 14.

Images