Optical device

Abstract

The present application relates to an optical device, which can ensure structural stability and good quality uniformity by properly maintaining a cell gap of a liquid crystal element, having excellent adhesion between an upper substrate and a lower substrate, and minimizing defects such as squeezing or pushing during lamination of an outer substrate.

Description

Technical Field

[0001] The present application relates to optical devices.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0142094, dated October 29, 2020, the disclosure of which is incorporated herein by reference in its entirety. Background Art

[0003] For long-term stability and large-area scalability of a liquid crystal cell using a flexible substrate, it is important to maintain a cell gap between an upper substrate and a lower substrate and to impart adhesion between the upper substrate and the lower substrate.

[0004] In non-patent document 1 ("Tight Bonding of Two Plastic Substrates for Flexible LCDs" SID Symposium Digest, 38, pp. 653 to 656 (2007)), a technique for forming an organic film pattern in the form of a column or wall having a cell gap height on one substrate and fixing it to an opposite substrate using an adhesive is disclosed. However, in such a technique, the adhesive must be located only on the column surface or the wall surface, but the technique of micro-stamping the adhesive on the column surface or the wall surface has high process difficulty; the control of the adhesive thickness and area is difficult; the adhesive is highly likely to be squeezed out when the upper substrate and the lower substrate are laminated; and there is a risk that the adhesive may contaminate the alignment film or the liquid crystal. Summary of the invention

[0005] Technical issues

[0006] In order to maintain the cell gap of the liquid crystal cell and ensure the adhesion between the upper substrate and the lower substrate, it is considered to form a spacer and an alignment film on the lower substrate, and to form a pressure-sensitive adhesive layer having both liquid crystal orientation force and adhesion force on the upper substrate, followed by lamination. However, since the modulus of the pressure-sensitive adhesive layer is very low, such a structure is easily affected by external pressure, making it difficult to obtain good appearance quality in an autoclave process under high temperature and pressure. Specifically, when the structural stability of the liquid crystal cell cannot be ensured in the autoclave process, defects such as cell gap collapse or liquid crystal flow and / or aggregation may occur, which leads to a decrease in the electro-optical properties and appearance uniformity of the liquid crystal cell.

[0007] The present application provides an optical device that can ensure structural stability and good quality uniformity by properly maintaining a cell gap of a liquid crystal cell, having excellent adhesion between an upper substrate and a lower substrate, and minimizing defects such as squeezing or aggregation.

[0008] Technical Solution

[0009] Among the physical properties mentioned in this specification, when the measurement temperature affects the result, unless otherwise stated, the relevant physical properties are physical properties measured at room temperature. The term room temperature is a natural temperature without heating or cooling, which is generally a temperature in the range of about 10°C to 30°C, or about 23°C or about 25°C. In addition, unless otherwise stated in this specification, the unit of temperature is °C. Among the physical properties mentioned in this specification, when the measurement pressure affects the result, unless otherwise stated, the relevant physical properties are physical properties measured at normal pressure. The term normal pressure is a natural pressure without pressurization or decompression, wherein generally about 1 atmosphere is referred to as normal pressure.

[0010] The present application relates to optical devices. Figure 1 The optical device of the present application is shown as an example. Figure 1 As shown, the optical device may include a first outer substrate 100a, a second outer substrate 100b disposed opposite to the first outer substrate 100a, and a liquid crystal element 300 located between the first outer substrate 100a and the second outer substrate 100b. The optical device may include at least one or more intermediate layers located between the first outer substrate and the liquid crystal element and between the second outer substrate and the liquid crystal element. Figure 1 An optical device including intermediate layers 200a, 200b respectively located between a first outer substrate 100a and a liquid crystal element 300 and between a second outer substrate 100b and a liquid crystal element 300 is exemplarily shown.

[0011] The optical device may further include an outer layer 400 surrounding the side of the liquid crystal element 300. The optical device according to the present application controls the relationship between the thickness of the outer layer and the liquid crystal element or the relationship between the storage elastic modulus of the outer layer and the pressure-sensitive adhesive layer, thereby minimizing extrusion and / or aggregation defects that may occur when laminating the optical device and the outer substrate.

[0012] In one example, the optical device of the present application may satisfy the following Formula 1.

[0013] [Formula 1]

[0014] -T2×0.4≤T1-T2≤T2×0.4

[0015] In Formula 1, T1 is the thickness of the outer layer, and T2 is the thickness of the liquid crystal cell.

[0016] When the outer layer is composed of a single layer or a single film, the thickness (T1) of the outer layer may refer to the thickness of the relevant layer or film. When the outer layer is composed of a plurality of layers or films, the thickness (T1) of the outer layer may refer to the sum of the thicknesses of the plurality of layers or films. The thickness (T2) of the liquid crystal cell may refer to, for example, the sum of the thicknesses of the first base layer, the pressure-sensitive adhesive layer, the spacer, and the second base layer.

[0017] When the difference (T1-T2) value of the thickness between the outer layer and the liquid crystal cell is too small, extrusion and / or agglomeration defects may occur in the liquid crystal cell when the optical device is laminated, so it may be preferred that the lower limit of the difference (T1-T2) value of the thickness between the outer layer and the liquid crystal cell is -T2×0.4 or more. Specifically, the lower limit of the difference (T1-T2) value of the thickness may be -T2×0.3 or more, -T2×0.2 or more, -T2×0.1 or more, -T2×0.08 or more, -T2×0.06 or more, -T2×0.04 or more, or -T2×0.02 or more.

[0018] When the difference (T1-T2) value of the thickness between the outer layer and the liquid crystal cell is too large, a crack defect of the outer substrate may occur when the optical device is laminated, so it is preferred that the upper limit of the difference (T1-T2) value of the thickness between the outer layer and the liquid crystal cell is T2×0.4 or less. Specifically, the upper limit of the difference (T1-T2) value of the thickness may be T2×0.35 or less, T2×0.3 or less, or T2×0.25 or less.

[0019] The thickness (T1) of the outer layer and the thickness (T2) of the liquid crystal element can be appropriately selected within the range satisfying Formula 1. In one example, the thickness (T1) of the outer layer can be in the range of 60 μm to 840 μm. In one example, the thickness (T2) of the liquid crystal element can be in the range of 100 μm to 800 μm.

[0020] In one example, the optical device of the present application may satisfy the following Formula 2.

[0021] [Formula 2]

[0022] G1≥G2

[0023] In Formula 2, G1 is the storage elastic modulus of the outer layer at 25° C., and G2 is the storage elastic modulus of the pressure-sensitive adhesive layer at 25° C. The storage elastic modulus may be a value measured at a frequency of 6 rad / sec.

[0024] When the storage elastic modulus (G1) of the outer layer is smaller than the storage elastic modulus (G2) of the pressure-sensitive adhesive layer, extrusion and / or aggregation defects may occur in the liquid crystal element when the optical device is laminated, so the storage elastic modulus (G1) of the outer layer can be controlled to be equal to the storage elastic modulus (G2) of the pressure-sensitive adhesive layer or greater than the storage elastic modulus (G2) of the pressure-sensitive adhesive layer.

[0025] When the outer layer is composed of a single layer or a single film, the storage elastic modulus (G1) of the outer layer may refer to the storage elastic modulus of the relevant layer or film. When the outer layer is composed of a plurality of layers or a plurality of films, the storage elastic modulus (G1) of the outer layer may refer to the storage elastic modulus of a laminate of a plurality of layers or a laminate of a plurality of films, or may refer to the storage elastic modulus of a single layer or a single film constituting a plurality of layers or a plurality of films.

[0026] In one example, when the storage elastic modulus value of the layer or film constituting the outer layer is differently measured according to the MD (machine direction) axis or the TD (transverse direction) axis, either the storage elastic modulus of the MD axis and the storage elastic modulus of the TD axis may satisfy the above Formula 2, or both the storage elastic modulus of the MD axis and the storage elastic modulus of the TD axis may satisfy the above Formula 2. The MD axis and the TD axis may be perpendicular to each other.

[0027] The difference (G1-G2) between the storage elastic modulus of the outer layer and the storage elastic modulus of the pressure-sensitive adhesive layer can be, for example, 9999.99MPa or less. When the difference (G1-G2) between the storage elastic modulus of the outer layer and the storage elastic modulus of the pressure-sensitive adhesive layer is too large, damage may occur when laminating with the outer substrate, so it can be advantageous to control within the above range. Specifically, the difference (G1-G2) in the storage elastic modulus can be 9,500MPa or less, 9,000MPa or less, 9,500MPa or less, 8,000MPa or less, 8,500MPa or less, 7,000MPa or 6,500MPa or less.

[0028] The difference (G1-G2) between the storage elastic modulus of the outer layer and the storage elastic modulus of the pressure-sensitive adhesive layer can be, for example, 0 MPa or more. When the difference (G1-G2) of the storage elastic modulus is too small, the extrusion and / or aggregation defects of the liquid crystal may not be effectively improved, so it may be advantageous to control within the above range. Specifically, the difference (G1-G2) of the storage elastic modulus can be 1 MPa or more, 5 MPa or more, 10 MPa or more, 20 MPa or more, 40 MPa or more, 60 MPa or more, or 80 MPa or more.

[0029] The storage elastic modulus (G1) of the outer layer and the storage elastic modulus (G2) of the pressure-sensitive adhesive layer may be appropriately selected within the range satisfying Formula 2. In one example, the storage elastic modulus (G1) of the outer layer may be in the range of 0.1 MPa to 10,000 MPa. Specifically, the storage elastic modulus (G1) of the outer layer can be 1 MPa or more, 5 MPa or more, 10 MPa or more, 100 MPa or more, 500 MPa or more, 1,000 MPa or more, or 1,500 MPa or more, and can be 10,000 MPa or less, 9,000 MPa or less, 8,000 MPa or less, 7,000 MPa or less, 6,000 MPa or less, 5,000 MPa or less, 4,000 MPa or less, 3000 MPa or less, 2,000 MPa or less, 1000 MPa or less, 800 MPa or less, 600 MPa or less, 400 MPa or less, 200 MPa or less, or 100 MPa or less.

[0030] In one example, the storage elastic modulus (G2) of the pressure-sensitive adhesive layer can be in the range of 0.01MPa to 1MPa. Specifically, the storage elastic modulus (G2) of the pressure-sensitive adhesive layer can be 0.02MPa or greater, 0.04MPa, 0.06MPa, 0.08MPa or 0.1MPa or greater, and can be 0.8MPa or less, 0.6MPa or less, 0.4MPa or less, or 0.2MPa or less. When the storage elastic modulus of the pressure-sensitive adhesive layer is too large, it may be difficult to meet the above conditions, and when the storage elastic modulus of the pressure-sensitive adhesive layer is too small, when the liquid crystal element is laminated, the pressure-sensitive adhesive layer is squeezed or pushed, thereby being able to suppress the electro-optical properties and appearance uniformity, so it can be advantageous to control the storage elastic modulus within the above range.

[0031] The optical device of the present application can simultaneously satisfy Formula 1 and Formula 2. In this way, extrusion and / or agglomeration defects that may occur when laminating the optical device can be effectively minimized.

[0032] The first outer substrate and the second outer substrate may be independently an inorganic substrate or a plastic substrate. A known inorganic substrate may be used as the inorganic substrate without any particular limitation. In one example, a glass substrate with excellent light transmittance may be used as the inorganic substrate. As examples of glass substrates, soda-lime glass substrates, general tempered glass substrates, borosilicate glass substrates or alkali-free glass substrates may be used, but are not limited thereto. As the plastic substrate, a cellulose film such as TAC (triacetyl cellulose) or DAC (diacetyl cellulose) can be used; a COP (cyclic olefin copolymer) film such as a norbornene derivative; an acrylic film such as Pac (polyacrylate) or PMMA (poly(methyl methacrylate)); a PC (polycarbonate) film; a polyolefin film such as PE (polyethylene) or PP (polypropylene); a PVA (polyvinyl alcohol) film; a PI (polyimide) film; a sulfone-based film such as a PSF (polysulfone) film, a PPS (polyphenylsulfone) film, or a PES (polyethersulfone) film; a PEEK (polyetheretherketone) film; a PEI (polyetherimide) film; a polyester-based film such as a PEN (polyethylene naphthalate) film or a PET (polyethylene terephthalate) film; or a fluororesin film, etc., but not limited thereto. In each of the first outer substrate and the second outer substrate, as required, a coating of gold, silver or a silicon compound (such as silicon dioxide or silicon monoxide) or a functional layer such as an antireflection layer may also be present.

[0033] In one example, the first outer substrate and / or the second outer substrate can be a glass substrate. In the automotive or window industry, in order to overcome the physical limitations of the liquid crystal element, the glass substrate can be laminated to both sides of the liquid crystal element, or the glass substrate can be laminated to one side of the liquid crystal element and the film substrate can be laminated to the other side of the liquid crystal element. In its automotive industry, it is necessary to laminate the glass substrate to both sides of the liquid crystal element via an adhesive layer. However, due to the use of a pressure-sensitive adhesive layer, the liquid crystal element is susceptible to external pressure, so defects such as cell gap collapse or flow or aggregation of liquid crystals may occur in the glass lamination process (such as an autoclave under high temperature and high pressure). According to the present invention, as described below, the thickness of the first intermediate layer and the second intermediate layer is controlled, so that defects can be minimized, and the structural stability and quality uniformity of the optical device can be ensured.

[0034] The thickness of the first outer substrate and the second outer substrate can be about 0.3 mm or more respectively. In another example, the thickness can be about 0.5 mm or more, 1 mm or more, 1.5 mm or more, or about 2 mm or more, and can also be about 10 mm or less, 9 mm or less, 8 mm or less, 7 mm or less, 6 mm or less, 5 mm or less, 4 mm or less, or about 3 mm or less.

[0035] The first outer substrate and the second outer substrate can be a flat substrate or can be a substrate with a curved surface shape. For example, the first outer substrate and the second outer substrate can be a flat substrate at the same time, have a curved surface shape at the same time, or either one can be a flat substrate and the other can be a substrate with a curved surface shape. In addition, at this, when having a curved surface shape at the same time, each curvature or radius of curvature can be the same or different. In this specification, curvature or radius of curvature can be measured in a manner known in the industry, for example, non-contact equipment such as 2D profile laser sensor, color confocal line sensor or 3D measurement confocal microscope can be used to measure. The method of measuring curvature or radius of curvature using such equipment is known.

[0036] With respect to the first outer substrate and the second outer substrate, for example, when the curvature or the radius of curvature on the front surface and the rear surface are different, the respective curvatures or the radius of curvature of the opposing surfaces (i.e., the curvature or the radius of curvature of the surface facing the second outer substrate in the case of the first outer substrate, and the curvature or the radius of curvature of the surface facing the first outer substrate in the case of the second outer substrate) can be a reference. In addition, when the relevant surface has a portion where the curvature or the radius of curvature is not constant and different, the maximum curvature or the radius of curvature can be a reference, or the minimum curvature or the radius of curvature can be a reference, or the average curvature or the average radius of curvature can be a reference.

[0037] The difference of curvature or radius of curvature of each of the first outer substrate and the second outer substrate can be within about 10%, within 9%, within 8%, within 7%, within 6%, within 5%, within 4%, within 3%, within 2% or within about 1%. When the large curvature or radius of curvature is CL and the small curvature or radius of curvature is CS, the difference of curvature or radius of curvature is the value calculated by 100%×(CL-CS) / CS. In addition, the lower limit of the difference of curvature or radius of curvature is not particularly limited. Since the difference of curvature or radius of curvature of the first outer substrate and the second outer substrate can be the same, the difference of curvature or radius of curvature can be about 0% or greater, or greater than about 0%. Such control of curvature or radius of curvature is useful in the structure of the liquid crystal element contacting the intermediate layer in the optical device of the present application. That is, when the difference in curvature or radius of curvature exceeds 10%, when the outer substrate and the liquid crystal cell are in contact with the intermediate layer to be described below, the problem of the combined outer substrate being scattered due to deterioration of the bonding force may occur at the same time. However, if it is controlled within 10%, the problem of the combined outer substrate being scattered due to deterioration of the bonding force can be effectively prevented.

[0038] The first outer substrate and the second outer substrate may have the same curvature sign. In other words, the first outer substrate and the second outer substrate may be bent in the same direction. That is, in the above case, the center of the curvature of the first outer substrate and the center of the curvature of the second outer substrate are both present in the same part of the upper and lower parts of the first outer substrate and the second outer substrate. When the first outer substrate and the second outer substrate are bent in the same direction, the first outer substrate and the second outer substrate can be more effectively combined by the intermediate layer, and after combining, the first outer substrate and the second outer substrate can be more effectively prevented from deteriorating the bonding force with the liquid crystal cell and / or the polarizer.

[0039] The specific range of the curvature or curvature radius of each of the first outer substrate and the second outer substrate is not particularly limited. In one example, the curvature radius of each of the first outer substrate and the second outer substrate may be about 100R or more, 200R or more, 300R or more, 400R or more, 500R or more, 600R or more, 700R or more, 800R or more, or about 900R or more, or may be about 10,000R or less, 9,000R or less, 8,000R or less, 7,000R or less, 600R or more, 700R or more, 800R or more, or about 900R or more. ,000R or less, 5,000R or less, 4,000R or less, 3,000R or less, 2,000R or less, 1,900R or less, 1,800R or less, 1,700R or less, 1,600R or less, 1,500R or less, 1,400R or less, 1,300R or less, 1,200R or less, 1,100R or less, or about 1,050R or less. Here, R means the curvature of a circle with a radius of 1mm. Therefore, here, for example, 100R is the curvature of a circle with a radius of 100mm or the radius of curvature of such a circle. The first outer substrate and the second outer substrate may have the same or different radii of curvature within the above range. In an example, when the curvatures of the first outer substrate and the second outer substrate are different from each other, the radius of curvature of the substrate with a large curvature may be within the above range. In one example, when the curvatures of the first outer substrate and the second outer substrate are different from each other, the substrate having a larger curvature may be a substrate disposed in the direction of gravity when the optical device is used. When the curvature or the radius of curvature of the first substrate and the second substrate is controlled as above, even if the bonding force caused by the intermediate layer described below is reduced, the net force as the sum of the restoring force and gravity can be used to prevent widening.

[0040] In one example, the optical device may not include polarizers between the first outer substrate and the liquid crystal element and between the second outer substrate and the liquid crystal element. Figure 1The optical device is exemplarily shown without any polarizer. In another example, the optical device may further include a polarizer in at least one position between the first outer substrate and the liquid crystal element and between the second outer substrate and the liquid crystal element. Figure 2 An optical device including a first polarizer 500a located between a first outer substrate and a liquid crystal cell and a second polarizer 500b located between a second outer substrate and the liquid crystal cell is exemplarily shown. The optical device may include an intermediate layer 200a located between the first outer substrate and the first polarizer, an intermediate layer 200b located between the first polarizer and the liquid crystal cell, an intermediate layer 200c located between the liquid crystal cell and the second polarizer, and an intermediate layer 200d located between the second polarizer and the second outer substrate.

[0041] In this specification, the term polarizer means a film, sheet or element having a polarization function. The polarizer is a functional element capable of extracting light vibrating in one direction from incident light vibrating in multiple directions.

[0042] The polarizer may be an absorptive polarizer or a reflective polarizer. In the present specification, an absorptive polarizer means an element that exhibits selective transmission and absorption characteristics relative to incident light. For example, a polarizer may transmit light vibrating in any one direction of incident light vibrating in multiple directions and may absorb light vibrating in other directions. In the present specification, a reflective polarizer means an element that exhibits selective transmission and reflection characteristics relative to incident light. For example, a polarizer may transmit light vibrating in any one direction of incident light vibrating in multiple directions and may reflect light vibrating in other directions. According to one example of the present application, the polarizer may be an absorptive polarizer.

[0043] The polarizer may be a linear polarizer. In this specification, a linear polarizer means a case where the light selectively transmitted is linearly polarized light vibrating in any one direction, and the light selectively absorbed or reflected is linearly polarized light vibrating in a direction perpendicular to the vibration direction of the linear polarized light. In the case of an absorptive linear polarizer, the light transmission axis and the light absorption axis may be perpendicular to each other. In the case of a reflective linear polarizer, the light transmission axis and the light reflection axis may be perpendicular to each other.

[0044] In one example, the polarizers may each be a stretched polymer film dyed with iodine or an anisotropic dye. As a stretched polymer film, a PVA (poly (vinyl alcohol)) stretched film may be exemplified. In another example, the first polarizer and the second polarizer may each be a guest-host polarizer, wherein a liquid crystal polymerized in an oriented state is a host, and an anisotropic dye arranged according to the orientation of the liquid crystal is a guest. In another example, the polarizers may each be a thermotropic liquid crystal film or a lyotropic liquid crystal film.

[0045] A protective film, an anti-reflection film, a delay film, a pressure-sensitive adhesive layer, an adhesive layer, a surface treatment layer, etc. can be formed on one side or both sides of the polarizer. The delay film can be, for example, a 1 / 4 wave plate or a 1 / 2 wave plate. The in-plane delay value of the 1 / 4 wave plate to the light with a wavelength of 550nm can be in the range of about 100nm to 180nm, which is 100nm or 150nm. The in-plane delay value of the 1 / 2 wave plate to the light with a wavelength of 550nm can be in the range of about 200nm to 300nm or 250nm to 300nm. The delay film can be, for example, a stretched polymer film or a liquid crystal polymer film.

[0046] The transmittance of each polarizer to light with a wavelength of 550nm may be in the range of 40% to 50%. The transmittance may refer to the single transmittance of the polarizer to light with a wavelength of 550nm. The single transmittance of the polarizer may be measured using, for example, a spectrometer (V7100, manufactured by Jasco). For example, after setting air as the baseline and measuring each transmittance in a state where the axis of the polarizer sample is vertically and horizontally aligned with the axis of the reference polarizer, the single transmittance may be calculated.

[0047] When it is assumed that a blocking state is achieved in the first orientation state of the liquid crystal element, the polarizer can be arranged in an optical device so that the angle formed by the average optical axis (the vector sum of the optical axes) of the first orientation state and the light absorption axis of the polarizer is about 80 degrees to about 100 degrees or about 85 degrees to about 95 degrees, or is approximately vertical, or the polarizer can be arranged in the optical device so that the angle is 35 degrees to about 55 degrees or about 40 degrees to about 50 degrees, or about 45 degrees.

[0048] Figure 3 The liquid crystal element is shown as an example. Figure 3 As shown in the figure, the liquid crystal element may include a first base layer 10a, a pressure-sensitive adhesive layer 10c formed on the inner side of the first base layer, a second base layer 20a arranged opposite to the first base layer 10a, a spacer 20c formed on the inner side of the second base layer 20a, and a liquid crystal layer 30 located between the first base layer 10a and the second base layer 20a.

[0049] As the first base layer and the second base layer, for example, an inorganic film such as a glass film, a crystalline or amorphous silicon film, or a quartz or ITO (Indium Tin Oxide) film, or a polymer film can be used, and in terms of realizing a flexible member, a polymer film can be used.

[0050] In one example, the first base layer and the second base layer can each be a polymer film. As the polymer film, TAC (triacetyl cellulose); COP (cyclic olefin copolymer) such as norbornene derivatives; PMMA (poly (methyl methacrylate)); PC (polycarbonate); PE (polyethylene); PP (polypropylene); PVA (polyvinyl alcohol); DAC (diacetyl cellulose); Pac (polyacrylate); PES (polyether sulfone); PEEK (polyether ether ketone); PPS (polyphenyl sulfone); PEI (polyetherimide); PEN (polyethylene naphthalate); PET (polyethylene terephthalate); PI (polyimide); PSF (polysulfone); PAR (polyarylate) or amorphous fluororesin, etc. can be used, but are not limited thereto. In the first base layer and the second base layer, as needed, there may also be a coating of gold, silver or a silicon compound (such as silicon dioxide or silicon monoxide), or a functional layer such as an anti-reflection layer.

[0051] The thickness of the first base layer and the second base layer may each be about 10 μm to about 1,000 μm. As another example, the thickness of the base layer may each be about 20 μm or more, 40 μm or more, 60 μm or more, 80 μm or more, 100 μm or more, 120 μm or more, 140 μm or more, 160 μm or more, or about 180 μm or more, and may be about 900 μm or less, 800 μm or less, 700 μm or less, 600 μm or less, 500 μm or less, or about 400 μm or less. When the thickness of the first base layer and the second base layer meets the above range, appearance defects such as wrinkles can be reduced when an optical device is manufactured by laminating a liquid crystal element with an outer substrate.

[0052] The pressure-sensitive adhesive layer may be optically transparent. The average transmittance of the pressure-sensitive adhesive layer for the visible light region (eg, wavelength of 380 nm to 780 nm) may be about 80% or more, 85% or more, 90% or more, or 95% or more.

[0053] The pressure-sensitive adhesive layer can be a pressure-sensitive adhesive layer of liquid crystal orientation. The pressure-sensitive adhesive layer can be, for example, a vertically oriented pressure-sensitive adhesive layer or a horizontally oriented pressure-sensitive adhesive layer. In this specification, "vertically oriented pressure-sensitive adhesive" can mean a pressure-sensitive adhesive having an attachment force that can combine the upper substrate and the lower substrate while giving the adjacent liquid crystal compound a vertical orientation force. In this specification, "horizontally oriented pressure-sensitive adhesive" can mean a pressure-sensitive adhesive having an attachment force that can combine the upper substrate and the lower substrate while giving the adjacent liquid crystal compound a horizontal orientation force. The pre-tilt angle of the adjacent liquid crystal compound relative to the vertically oriented pressure-sensitive adhesive can be in the range of 80 to 90 degrees, 85 to 90 degrees, or about 87 to 90 degrees, and the pre-tilt angle of the adjacent liquid crystal compound relative to the horizontally oriented pressure-sensitive adhesive can be in the range of 0 to 10 degrees, 0 to 5 degrees, or 0 to 3 degrees.

[0054] In the present specification, the pretilt angle may mean an angle formed by the director of the liquid crystal compound relative to a plane horizontal to the pressure-sensitive adhesive or alignment film of the liquid crystal orientation in a state where no voltage is applied. In the present specification, the director of the liquid crystal compound may mean an optical axis or a slow axis of the liquid crystal layer. Alternatively, the director of the liquid crystal compound may mean a long axis direction when the liquid crystal compound has a rod shape, and may mean an axis parallel to the normal direction of the disk plane when the liquid crystal compound has a disk shape.

[0055] The thickness of the pressure-sensitive adhesive layer may be, for example, in the range of 3 μm to 15 μm. When the thickness of the pressure-sensitive adhesive layer is within the above range, it may be advantageous to minimize defects such as squeezing or pushing of the pressure-sensitive adhesive when used in the manufacture of a liquid crystal element while ensuring the adhesion between the upper substrate and the lower substrate.

[0056] As the pressure-sensitive adhesive layer, various types of pressure-sensitive adhesives known in the industry as so-called OCA (optically clear adhesive) can be appropriately used. The pressure-sensitive adhesive may be different from an OCR (optically clear resin) type adhesive that cures after the objects to be attached are bonded, because it cures before the objects to be attached are bonded. As the pressure-sensitive adhesive, for example, an acrylic, silicone-based, epoxy-based, or urethane-based pressure-sensitive adhesive can be applied.

[0057] The pressure-sensitive adhesive layer may include a cured product of a pressure-sensitive adhesive resin. In one example, the pressure-sensitive adhesive layer may include a silicone-based pressure-sensitive adhesive. The silicone pressure-sensitive adhesive may include a cured product of a curable silicone compound as the pressure-sensitive adhesive resin.

[0058] The type of the curable organic silicon compound is not particularly limited, and for example, a heat-curable organic silicon compound or an ultraviolet-curable organic silicon compound may be used. The curable organic silicon compound may be referred to as a pressure-sensitive adhesive resin.

[0059] In one example, the curable organosilicon compound may be an addition curing organosilicon compound.

[0060] Specifically, the addition-curing organosilicon compound can be exemplified by (1) an organopolysiloxane containing two or more alkenyl groups in the molecule and (2) an organopolysiloxane containing two or more silicon-bonded hydrogen atoms in the molecule, but is not limited thereto. Such an organosilicon compound can form a cured product by an addition reaction, for example, in the presence of a catalyst to be described below.

[0061] More specific examples of (1) organopolysiloxanes that can be used in the present application may include: dimethylsiloxane-methylvinylsiloxane copolymers terminated with trimethylsiloxane groups at both ends of the molecular chain; methylvinylpolysiloxane terminated with trimethylsiloxane groups at both ends of the molecular chain; dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane copolymers terminated with trimethylsiloxane groups at both ends of the molecular chain; dimethylpolysiloxane terminated with dimethylvinylsiloxane groups at both ends of the molecular chain; methylvinylpolysiloxane terminated with dimethylvinylsiloxane groups at both ends of the molecular chain; dimethylsiloxane-methylvinylsiloxane copolymers terminated with dimethylvinylsiloxane groups at both ends of the molecular chain; dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane copolymers terminated with dimethylvinylsiloxane groups at both ends of the molecular chain; 1 2SiO 1 / 2 The siloxane units represented by R 1 2R 2 SiO 1 / 2 The siloxane units represented by SiO 4 / 2 An organopolysiloxane copolymer of a siloxane unit represented by 1 2R 2 SiO 1 / 2 The siloxane units represented by SiO 4 / 2 An organopolysiloxane copolymer of a siloxane unit represented by 1 R 2 SiO 2 / 2 The siloxane units represented by R 1 SiO 3 / 2 The siloxane unit represented by R 2 SiO 3 / 2 An organic polysiloxane copolymer of a siloxane unit represented by; and a mixture of two or more of the foregoing, but not limited thereto. Here, R1 is a hydrocarbon group other than an alkenyl group, specifically, an alkyl group such as methyl, ethyl, propyl, butyl, pentyl, hexyl or heptyl; an aryl group such as phenyl, tolyl, xylyl or naphthyl; an aralkyl group such as benzyl or phenethyl; a halogen-substituted alkyl group such as chloromethyl, 3-chloropropyl or 3,3,3-trifluoropropyl; and the like. In addition, herein, R 2 is an alkenyl group, specifically, it may be a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group or a heptenyl group or the like.

[0062] More specific examples of (2) organopolysiloxanes that can be used in the present application may include: methylhydrogenpolysiloxane terminated with trimethylsiloxane groups at both ends of the molecular chain; dimethylsiloxane-methylhydrogen copolymer terminated with trimethylsiloxane groups at both ends of the molecular chain; dimethylsiloxane-methylhydrogensiloxane-methylphenylsiloxane copolymer terminated with trimethylsiloxane groups at both ends of the molecular chain; dimethylpolysiloxane terminated with dimethylhydrogensiloxane groups at both ends of the molecular chain; dimethylsiloxane-methylphenylsiloxane copolymer terminated with dimethylhydrogensiloxane groups at both ends of the molecular chain; methylphenylpolysiloxane terminated with dimethylhydrogensiloxane groups at both ends of the molecular chain; 1 3SiO 1 / 2 The siloxane unit represented by R 1 2HSiO 1 / 2 The siloxane units represented by SiO 4 / 2 An organopolysiloxane copolymer of a siloxane unit represented by 1 2HSiO 1 / 2 The siloxane units represented by SiO 4 / 2 An organopolysiloxane copolymer of a siloxane unit represented by 1 HSiO 2 / 2 The siloxane units represented by R 1 SiO 3 / 2 Siloxane units represented by HSiO 3 / 2 An organic polysiloxane copolymer of a siloxane unit represented by; and a mixture of two or more of the foregoing, but not limited thereto. Here, R 1 is a hydrocarbon group other than an alkenyl group, specifically, it may be an alkyl group such as methyl, ethyl, propyl, butyl, pentyl, hexyl or heptyl; an aryl group such as phenyl, tolyl, xylyl or naphthyl; an aralkyl group such as benzyl or phenethyl; a halogen-substituted alkyl group such as chloromethyl, 3-chloropropyl or 3,3,3-trifluoropropyl; and the like.

[0063] When the pressure-sensitive adhesive layer is a vertically oriented pressure-sensitive adhesive layer, the surface energy can be 16mN / m or less. The lower limit of the surface energy can be, for example, 5mN / m or more. When the pressure-sensitive adhesive layer is a horizontally oriented pressure-sensitive adhesive layer, the surface energy can be greater than 16mN / m. The upper limit of the surface energy can be, for example, 50mN / m or less. The surface energy can be measured using a drop shape analyzer (DSA100 product of KRUSS). Specifically, repeat 5 times the deionized water with known surface tension is dropped on the surface of the pressure-sensitive adhesive to obtain the process of contact angle, thereby obtaining the mean value of five contact angle values ​​of obtained, and similarly repeat 5 times the diiodomethane with known surface tension is dropped thereon to obtain the process of contact angle, thereby obtaining the mean value of five contact angle values ​​of obtained. Then, by utilizing the mean value of the contact angle of the deionized water and diiodomethane obtained, the surface energy is obtained by substituting the numerical value (Strom value) of the surface tension of the solvent through the Owens-Wendt-Rabel-Kaelble method. The surface energy (γ surface) of a sample can be calculated by considering the dispersion forces between non-polar molecules and the interaction forces between polar molecules (γ surface = γ dispersion + γ polarity), where the ratio of the polar term (γ polarity) in the surface energy γ surface can be defined as the polarity of the surface.

[0064] The upper substrate and the lower substrate of the liquid crystal cell can be attached to each other through a pressure-sensitive adhesive layer. Specifically, the pressure-sensitive adhesive layer of the upper substrate and the spacer of the lower substrate can be attached to each other. When an alignment film is formed on the spacer of the lower substrate, the region of the alignment film corresponding to the spacer can be attached to the pressure-sensitive adhesive layer of the upper substrate.

[0065] The liquid crystal layer may contain a liquid crystal compound. As the liquid crystal compound, a liquid crystal compound whose orientation direction can be changed by applying an external action can be used. In this specification, the term "external action" may mean any external factor (such as an external voltage, etc.) that can affect the behavior of the material contained in the liquid crystal layer. Therefore, a state without an external action may mean a state in which no external voltage, etc. is applied.

[0066] The type and physical properties of the liquid crystal compound can be appropriately selected in consideration of the purpose of the present application. In one example, the liquid crystal compound may be a nematic liquid crystal or a smectic liquid crystal. Nematic liquid crystal may mean a liquid crystal in which rod-like liquid crystal molecules are arranged in parallel in the long axis direction of the liquid crystal molecules, but their positions are irregular. Smectic liquid crystal may mean a liquid crystal in which rod-like liquid crystal molecules are regularly arranged to form a layered structure and are regularly arranged in parallel in the long axis direction. According to one example of the present application, the liquid crystal compound may be a nematic liquid crystal compound.

[0067] As a nematic liquid crystal compound, a liquid crystal compound having a clearing point of, for example, about 40°C or higher, about 50°C or higher, about 60°C or higher, about 70°C or higher, about 80°C or higher, about 90°C or higher, about 100°C or higher, or about 110°C or higher, or having a phase transition point within the above range (i.e., a phase transition point from a nematic phase to an isotropic phase) can be selected. In one example, the clearing point or phase transition point can be about 160°C or lower, about 150°C or lower, or about 140°C or lower.

[0068] The liquid crystal compound may be a non-reactive liquid crystal compound. A non-reactive liquid crystal compound may mean a liquid crystal compound having no polymerizable group. The polymerizable group may be exemplified by an acryloyl group, an acryloyloxy group, a methacryloyl group, a methacryloyloxy group, a carboxyl group, a hydroxyl group, a vinyl group, or an epoxy group, but is not limited thereto, and may include a functional group referred to as a polymerizable group.

[0069] The dielectric anisotropy of the liquid crystal compound may be positive or negative. The absolute value of the dielectric anisotropy of the liquid crystal compound may be appropriately selected in consideration of the purpose of the present application. The term "dielectric anisotropy (Δε)" may refer to the difference between the horizontal dielectric constant (ε / / ) and the vertical dielectric constant (ε / / ) of the liquid crystal. ⊥ ) (ε / / -ε ⊥ In this specification, the term horizontal dielectric constant (ε / / ) means a dielectric constant value measured along the direction of the electric field in a state where a voltage is applied so that the director of the liquid crystal and the direction of the electric field generated by the applied voltage are substantially horizontal, and the vertical dielectric constant (ε ⊥ ) means a dielectric constant value measured along the direction of the electric field in a state where a voltage is applied so that the director of the liquid crystal and the direction of the electric field generated by the applied voltage are substantially perpendicular.

[0070] The refractive index anisotropy of the liquid crystal compound can be appropriately selected in consideration of the purpose of the present application. In the present specification, the term "refractive index anisotropy" may mean the difference between the extraordinary refractive index and the ordinary refractive index of the liquid crystal compound. The refractive index anisotropy of the liquid crystal compound may be, for example, 0.01 to 0.3. The refractive index anisotropy may be 0.01 or greater, 0.05 or greater, or 0.07 or greater, and may be 0.3 or less, 0.2 or less, 0.15 or less, or 0.13 or less.

[0071] The liquid crystal layer may further include a dichroic dye. When the liquid crystal layer includes a dichroic dye, even if the liquid crystal element includes a pressure-sensitive adhesive layer, cell gap fluctuation is less affected during the lamination process of the outer substrate, thereby having an advantage that the thickness of the intermediate layer can be made relatively thin to ensure structural stability and quality uniformity of the liquid crystal element.

[0072] Dichroic dyes can control the variable transmittance characteristics of the liquid crystal layer. In the present specification, the term "dye" may mean a material that can strongly absorb and / or change light in at least a part or all of the visible light region (e.g., in the wavelength range of 400 nm to 700 nm), and the term "dichroic dye" may mean a material that can anisotropically absorb light in at least a part or all of the visible light region.

[0073] The liquid crystal layer containing liquid crystal compounds and dichroic dyes can be a GHLC layer (guest-host liquid crystal layer). In the present specification, "GHLC layer (guest-host liquid crystal layer)" can mean a functional layer in which dichroic dyes are arranged together according to the arrangement of liquid crystal compounds to exhibit anisotropic light absorption characteristics relative to the alignment direction of the dichroic dyes and the direction perpendicular to the alignment direction, respectively. For example, a dichroic dye is a substance whose light absorptivity varies with the polarization direction, wherein if the absorptivity of light polarized in the long axis direction is large, it can be referred to as a p-type dye, and if the absorptivity of polarized light in the short axis direction is large, it can be referred to as an n-type dye. In one example, when a p-type dye is used, polarized light vibrating in the long axis direction of the dye can be absorbed and polarized light vibrating in the short axis direction of the dye can be less absorbed and transmitted. In the following, unless otherwise specified, the dichroic dye is considered to be a p-type dye.

[0074] As a dichroic dye, for example, a known dye known to have a property of being able to align according to the alignment state of a liquid crystal compound by a so-called guest-host effect can be selected and used. Examples of such dichroic dyes include azo dyes, anthraquinone dyes, methine dyes, azomethine dyes, merocyanine dyes, naphthoquinone dyes, tetrazine dyes, phenylene dyes, quaterrylene dyes, benzothiadiazole dyes, diketopyrrolopyrrole dyes, squarylium dyes or pyromethene dyes, etc., but the dyes applicable to the present application are not limited thereto.

[0075] As the dichroic dye, a dye having a dichroic ratio (i.e., a value obtained by dividing the absorbance of polarized light parallel to the long axis direction of the dichroic dye by the absorbance of polarized light parallel to the direction perpendicular to the long axis direction) of 5 or more, 6 or more, or 7 or more can be used. The dye may satisfy the dichroic ratio at at least a portion of the wavelengths or any wavelength within the wavelength range of the visible light region (e.g., within the wavelength range of about 380 nm to 700 nm or about 400 nm to 700 nm). The upper limit of the dichroic ratio may be, for example, about 20 or less, 18 or less, 16 or less, or 14 or less.

[0076] The content of the dichroic dye in the liquid crystal layer can be appropriately selected considering the purpose of the present application. For example, the content of the dichroic dye in the liquid crystal layer can be 0.1 wt % or more, 0.25 wt % or more, 0.5 wt % or more, 0.75 wt % or more, 1 wt % or more, 1.25 wt % or more, or 1.5 wt % or more. The upper limit of the content of the dichroic dye in the liquid crystal layer can be, for example, 5.0 wt % or less, 4.0 wt % or less, 3.0 wt % or less, 2.75 wt % or less, 2.5 wt % or less, 2.25 wt % or less, 2.0 wt % or less, 1.75 wt % or less, or 1.5 wt % or less. When the content of the dichroic dye in the liquid crystal layer satisfies the above range, an optical device with excellent variable transmittance characteristics can be provided. In an example, as the content of the dichroic dye increases within the above range, an optical device with excellent variable transmittance characteristics can be provided.

[0077] The thickness of the liquid crystal layer is not particularly limited, for example, the thickness of the liquid crystal layer may be about 0.01 μm or more, 0.05 μm or more, 0.1 μm or more, 0.5 μm or more, 1 μm or more, 1.5 μm or more, 2 μm or more, 2.5 μm or more, 3 μm or more, 3.5 μm or more, 4 μm or more, 4.5 μm or more, 5 μm or more, 5.5 μm or more, 6 μm or more, 6.5 μm or more, 7 μm or more, 7.5 μm or more, 8 μm or more, 8.5 μm or more, 9 μm or more, or 9.5 μm or more. The upper limit of the thickness of the liquid crystal layer is not particularly limited, and it may generally be about 30 μm or less, 25 μm or less, 20 μm or less, or 15 μm or less.

[0078] The liquid crystal layer can be switched between a first orientation state and a second orientation state different from the first orientation state. The switching can be regulated, for example, by applying external energy such as voltage. For example, the liquid crystal layer can maintain any one of the first orientation state and the second orientation state in a state where no voltage is applied, and can be switched to another orientation state by voltage application.

[0079] As the first alignment state and / or the second alignment state, a horizontal alignment state, a vertical alignment state, a twisted alignment state, a tilted alignment state, a mixed alignment state, etc. can be exemplified.

[0080] In the present specification, the "horizontally aligned state" is a state in which the director of the liquid crystal compound in the liquid crystal layer is arranged approximately parallel to the plane of the liquid crystal layer, wherein, for example, the angle formed by the director of the liquid crystal compound relative to the plane of the liquid crystal layer may be, for example, in the range of approximately -10 degrees to 10 degrees or -5 degrees to 5 degrees, or it may form approximately 0 degrees.

[0081] In the present specification, the "vertical orientation state" is a state in which the director of the liquid crystal compound in the liquid crystal layer is arranged approximately perpendicular to the plane of the liquid crystal layer, wherein, for example, the angle formed by the director of the liquid crystal compound relative to the plane of the liquid crystal layer can be, for example, in the range of about 80 degrees to 100 degrees or 85 degrees to 95 degrees, or it can form about 90 degrees.

[0082] In the present specification, "twisted orientation state" may mean a spiral structure in which the directors of the liquid crystal compounds in the liquid crystal layer form a layer while twisting and aligning along an imaginary spiral axis. The twisted orientation state may be realized in a vertical orientation state, a horizontal orientation state, or a tilted orientation state. That is, the vertical twisted orientation mode is a state in which each liquid crystal compound forms a layer while twisting along the spiral axis in the vertical orientation state; the horizontal twisted orientation mode is a state in which each liquid crystal compound forms a layer while twisting along the spiral axis in the horizontal orientation state; and the tilted twisted orientation mode is a state in which each liquid crystal compound forms a layer while twisting along the spiral axis in the tilted orientation state.

[0083] In the present specification, a "tilted orientation state" may mean an orientation state in which the tilt angle (which is the angle formed by the director of the liquid crystal compound in the liquid crystal layer relative to the plane of the liquid crystal layer) is outside the tilt angle of the horizontal orientation state and the tilt angle of the vertical orientation state. In the tilted orientation state, the tilt angle may be, for example, greater than 10 degrees to less than 80 degrees. In the present specification, a "mixed orientation state" may mean an orientation state in which the tilt angle (which is the angle formed by the director of the liquid crystal compound in the liquid crystal layer relative to the plane of the liquid crystal layer) gradually increases or decreases along the thickness direction of the liquid crystal layer.

[0084] The liquid crystal element may further include a first electrode layer 10b formed on the inner surface of the first base layer 10a. At this time, the pressure-sensitive adhesive layer 10c may be present on the inner surface of the first electrode layer 10b. That is, the first electrode layer 10b may be present between the first base layer 10a and the pressure-sensitive adhesive layer 10c. The liquid crystal element may further include a second electrode layer 20b formed on the inner surface of the second base layer 20a. At this time, the spacer 20c may be present on the inner surface of the second electrode layer 20b. That is, the second electrode layer 20b may be present between the second base layer 20a and the spacer 20c.

[0085] The first electrode layer and the second electrode layer can be used to provide an external effect (such as an electric field) so that the material contained in the liquid crystal layer transmits or blocks incident light. In one example, the first electrode layer and / or the second electrode layer may include a conductive polymer, a conductive metal, a conductive nanowire, or a metal oxide such as ITO (indium tin oxide), etc., but is not limited thereto. The upper second electrode layer and / or the lower second electrode layer can be formed by, for example, depositing a conductive polymer, a conductive metal, a conductive nanowire, or a metal oxide such as ITO (indium tin oxide).

[0086] The liquid crystal element may further include an alignment film 20d on the inner surface of the second electrode layer 20b. A spacer 20c may be present between the second electrode layer 20b and the alignment film 20d. The alignment film may be formed on the spacer. That is, the top surface portion and / or the side surface portion of the spacer may contact the alignment film. The bottom surface of the spacer may contact the second electrode layer. Since the pressure-sensitive adhesive layer may have liquid crystal orientation characteristics, the alignment film may not be included on the inner surface of the first electrode layer. The alignment film may not be included on the inner surface of the first base layer.

[0087] In this specification, the combination of the first base layer, the first electrode layer and the pressure-sensitive adhesive layer may be referred to as an upper substrate, and the combination of the second base layer, the second electrode layer, the spacer and the alignment film may be referred to as a lower substrate. In the liquid crystal cell, the upper substrate may not include a separate alignment film except the pressure-sensitive adhesive layer, and the lower substrate may include the alignment film.

[0088] The alignment film and the liquid crystal layer may be in contact with each other. The alignment film may be a vertical alignment film or a horizontal alignment film. In the present specification, "horizontal alignment film" may mean a layer containing an alignment material that imparts a horizontal alignment force to the liquid crystal compounds present in the adjacent liquid crystal layer. In the present specification, "vertical alignment film" may mean a layer containing an alignment material that imparts a vertical alignment force to the liquid crystal compounds present in the adjacent liquid crystal layer. The pre-tilt angle of the adjacent liquid crystal compounds relative to the vertical alignment film may be in the range of 80 to 90 degrees, 85 to 90 degrees, or about 87 to 90 degrees, and the pre-tilt angle of the adjacent liquid crystal compounds relative to the horizontal alignment film may be in the range of 0 to 10 degrees, 0 to 5 degrees, or 0 to 3 degrees. Unlike the pressure-sensitive adhesive layer, the alignment film may not have an adhesive force for bonding the upper substrate and the lower substrate. In one example, in Figure 2 In a state of the liquid crystal device, the alignment film can have a peeling force close to zero with respect to the first base layer.

[0089] The alignment film may be a rubbing alignment film or a photo-alignment film. The orientation direction of the alignment film may be a rubbing direction in the case of a rubbing alignment film, and may be a direction of polarized light to be irradiated in the case of a photo-alignment film, wherein such an orientation direction may be determined by a detection method using an absorbing linear polarizer. Specifically, the orientation direction may be determined by placing an absorbing linear polarizer on one side of the liquid crystal layer in a state where the liquid crystal compound contained in the liquid crystal layer is horizontally oriented, and measuring the transmittance while rotating the polarizer 360 degrees. When light is irradiated to one side of the liquid crystal layer or the absorbing linear polarizer in the above state and the brightness (transmittance) is measured from the other side at the same time, if the absorption axis or the transmission axis is consistent with the orientation direction of the liquid crystal alignment film, the transmittance tends to be low, wherein the orientation direction may be determined by a simulation reflecting the refractive index anisotropy of the applied liquid crystal compound, etc. A method for determining the orientation direction according to the pattern of the liquid crystal layer is known, and in the present application, the orientation direction of the alignment film may be determined by such a known method.

[0090] The alignment film may include one or more selected from the following: materials known to exhibit orientation ability through friction orientation, such as polyimide compounds, poly(vinyl alcohol) compounds, poly(amic acid) compounds, polystyrene compounds, polyamide compounds and polyoxyethylene compounds; or materials known to exhibit orientation ability through light irradiation, such as polyimide compounds, polyamic acid compounds, polynorbornene compounds, phenylmaleimide copolymer compounds, polyvinyl cinnamate compounds, polyazobenzene compounds, polyethyleneimide compounds, polyvinyl alcohol compounds, polyamide compounds, polyethylene compounds, polystyrene compounds, polyphenylene phthalamide compounds, polyester compounds, CMPI (chloromethylated polyimide) compounds, PVCI (polyvinylcinnamate) compounds and polymethyl methacrylate compounds, but are not limited thereto.

[0091] The spacer (20c) may maintain a gap between the upper substrate and the lower substrate. The liquid crystal layer may exist in a region between the upper substrate and the lower substrate where the spacer does not exist.

[0092] The spacer may be a patterned spacer. The patterned spacer maintains a gap between the first base layer and the second base layer. The spacer may have a column shape or a partition wall shape. The partition wall may separate the space between the lower substrate and the upper substrate into two or more spaces. In an area where the spacer is not present, other films or other layers present in the lower portion may be exposed. For example, the second electrode layer may be exposed in an area where the spacer is not present. The alignment film may cover the spacer and the second electrode layer exposed in an area where the spacer is not present. In a liquid crystal cell in which the upper substrate and the lower substrate are combined together, the alignment film of the lower substrate present on the spacer and the pressure-sensitive adhesive layer of the upper substrate may contact each other.

[0093] Liquid crystal compounds and the above-mentioned additives such as dichroic dyes, chiral agents, etc. may be present in the region between the upper substrate and the lower substrate where no spacer exists. The shape of the spacer is not particularly limited, and it can be applied without limitation to have a polyhedron such as a circular, elliptical or other polygonal shape.

[0094] The spacer may include a curable resin. The type of curable resin is not particularly limited, wherein, for example, a thermosetting resin or a photocurable resin such as a UV-curable resin may be used. As a thermosetting resin, for example, a silicone resin, a silicone resin, a furan resin, a polyurethane resin, an epoxy resin, an amino resin, a phenolic resin, a urea resin, a polyester resin or a melamine resin may be used, but is not limited thereto. As a UV-curable resin, an acrylic resin may be used generally, such as a polyester acrylate polymer, a polystyrene acrylate polymer, an epoxy acrylate polymer, a polyurethane acrylate polymer or a polybutadiene acrylate polymer, a silicone acrylate polymer or an alkyl acrylate polymer, but is not limited thereto.

[0095] The spacer can be formed by a patterning process. For example, the spacer can be formed by a photolithography process. The photolithography process may include a process of applying a curable resin composition to a base layer or an electrode layer, and then irradiating it with ultraviolet light via a pattern mask. The pattern mask can be patterned into an ultraviolet transmission area and an ultraviolet blocking area. The photolithography process may also include a process of washing the curable resin composition irradiated with ultraviolet light. The area irradiated with ultraviolet light is cured, while the area not irradiated with ultraviolet light remains in a liquid phase, so the liquid phase is removed by a washing process, so that it can be patterned into a partition wall shape. In the photolithography process, the pattern mask may be subjected to a release process so that the resin composition and the pattern mask can be easily separated after ultraviolet irradiation, or a release paper may be placed between the layer of the resin composition and the pattern mask.

[0096] The width (line width), spacing (pitch), thickness and area of ​​the spacer can be appropriately selected within the range that does not harm the purpose of the present application. For example, the width (line width) of the spacer can be in the range of 10μm to 500μm or in the range of 10μm to 50μm. The spacing (pitch) of the spacer can be in the range of 10μm to 1000μm or in the range of 100μm to 1000μm. Relative to 100% of the total area of ​​the second base layer, the area of ​​the spacer can be about 5% or more and can be 50% or less. When the area of ​​the spacer is within the above range, it can be beneficial to ensure excellent electro-optical properties while fully ensuring the adhesion between the upper substrate and the lower substrate. The thickness of the spacer can be in the range of, for example, 1μm to 30μm or 3μm to 20μm.

[0097] The optical device may include at least one or more intermediate layers between the first outer substrate and the liquid crystal cell, and may include at least one or more intermediate layers between the second outer substrate and the liquid crystal cell. Therefore, the optical device may include at least two intermediate layers. One side of each of the first outer substrate and the second outer substrate may contact the adjacent intermediate layer. The two sides of the liquid crystal cell may contact the adjacent intermediate layers respectively.

[0098] The number of intermediate layers of the optical device can be determined according to whether the optical device includes other elements in addition to the first outer substrate, the second outer substrate and the liquid crystal element. Other elements can be exemplified by polarizers and the like.

[0099] In an example, optical device can also include other elements such as polarizers between the first outer substrate and the second outer substrate in addition to liquid crystal cell. In this case, as an embodiment, optical device can have a structure in which the first outer substrate, intermediate layer, liquid crystal cell, intermediate layer, polarizer, intermediate layer and the second outer substrate are laminated in this order. In another embodiment, optical device can have a structure in which the first outer substrate, intermediate layer, polarizer, intermediate layer, liquid crystal cell, intermediate layer and the second outer substrate are laminated in this order. As another example, optical device can have a structure in which the first outer substrate, intermediate layer, polarizer, intermediate layer, liquid crystal cell, intermediate layer, polarizer, intermediate layer and the second outer substrate are laminated in this order.

[0100] In another example, the optical device may not include other elements such as a polarizer between the first outer substrate and the second outer substrate except the liquid crystal element. In this case, the optical device may have a structure in which the first outer substrate, the intermediate layer, the liquid crystal element, the intermediate layer and the second outer substrate are laminated in this order.

[0101] In order to overcome the physical limitations of the liquid crystal cell, the outer substrates can be bonded together via an intermediate layer on both sides of the liquid crystal cell, but due to the low modulus of the pressure-sensitive adhesive layer, it is easily affected by external pressure, so that defects such as cell gap collapse or liquid crystal flow or aggregation may occur. The thickness of the intermediate layer included in the optical device is controlled so that the defects can be minimized and the structural stability and uniform appearance characteristics of the optical device can be ensured.

[0102] As an example, the total thickness of at least one or more intermediate layers may be 800 μm or greater. The total thickness of at least one or more intermediate layers means the sum of the thicknesses of all intermediate layers present between the first outer substrate and the liquid crystal cell and between the second outer substrate and the liquid crystal cell. When the total thickness of the intermediate layers is within the above range, the structural stability and uniform appearance characteristics of the optical device can be ensured by minimizing defects in the lamination process of the outer substrate. Specifically, the sum of the total thickness of at least one or more intermediate layers may be 900 μm or more, 1,000 μm or more, 1,100 μm or more, 1200 μm or more, 1,300 μm or more, 1,400 μm or more, 1,500 μm or more, 1,600 μm or more, about 1,650 μm or more, 1,700 μm or more, 1,750 μm or more, 1,800 μm or more, 1,850 μm or more, 1,900 μm or more, 1,950 μm or more, 2,000 μm or more, 2,100 μm or more, 2,150 μm or more, or about 2,200 μm or more. The total thickness of at least one or more intermediate layers may be, for example, about 6,000 μm or less, 5,900 μm or less, 5,800 μm or less, 5,700 μm or less, 5,600 μm or less, 5,500 μm or less, 5,400 μm or less, 5,300 μm or less, 5,200 μm or less, 5,100 μm or less, or about 5,000 μm or less. When the total thickness of at least one or more intermediate layers is too thick, the electro-optical characteristics of the optical device, such as the transmission characteristics, may be deteriorated, and thus it may be advantageous within the above range.

[0103] At least one or more intermediate layers may each have a single layer structure of one intermediate layer or may be a laminate of two or more sub-intermediate layers. The thickness and number of the sub-intermediate layers may be controlled in consideration of the desired thickness of the intermediate layer. In an example, the thickness of the sub-intermediate layer may be in the range of 100 μm to 500 μm, or in the range of 300 μm to 400 μm.

[0104] As an example, the total thickness (Ta) of at least one or more intermediate layers between the first outer substrate and the liquid crystal element and the total thickness (Tb) of at least one or more intermediate layers between the second outer substrate and the liquid crystal element may be about 400 μm or more, 500 μm or more, 600 μm or more, 700 μm or more, 800 μm or more, 900 μm or more, 1000 μm or more, or 1100 μm or more, and may be about 3,000 μm or less, 2,900 μm or less, 2,800 μm or less, 2,700 μm or less, about 2,600 μm or less, about 2,500 μm or less, about 2,400 μm or less, or about 2,300 μm or less. When the thickness Ta and Tb are within the above range, it is advantageous to ensure structural stability and uniform appearance characteristics without defects during the lamination process of the outer substrate, without damaging the electro-optical characteristics of the optical device. The sum of the total thickness (Ta) of at least one or more intermediate layers between the first outer substrate and the liquid crystal cell means the sum of the thickness of all intermediate layers between the first outer substrate and the liquid crystal cell. In addition, the sum of the total thickness (Tb) of at least one intermediate layer between the second outer substrate and the liquid crystal cell means the sum of the thickness of all intermediate layers between the second outer substrate and the liquid crystal cell.

[0105] As an example, the total thickness (Ta) of at least one or more intermediate layers between the first outer substrate and the liquid crystal element and the total thickness (Tb) of at least one or more intermediate layers between the second outer substrate and the liquid crystal element (Ta / Tb) can be in the range of 0.1 to 10. As another example, the thickness ratio (Ta / Tb) can be about 0.12 or more, about 0.13 or more, or about 0.14 or more, and can be about 9.5 or less, 9.0 or less, 8.5 or less, 8.0 or less, 7.5 or less, or about 7.0 or less. When the thickness ratio is in the range of 0.1 to 10, the appearance defects of the liquid crystal element can be more effectively improved.

[0106] As an example, the storage elastic modulus of at least one or more intermediate layers can each be 1MPa or greater. When the storage elastic modulus of the intermediate layer is low, the liquid crystal element may also be damaged due to the stress of the shrinkage and expansion in the base layer that cannot withstand the high temperature durability test or the cycle test. The storage elastic modulus of the intermediate layer can be 2MPa or greater, or 4MPa or greater, and can be 100MPa or less, 80MPa or less, 60MPa or less, 40MPa or less, 20MPa or less, 10MPa or less, or 5MPa or less. The storage elastic modulus can be a value measured at a temperature of 25°C and a frequency of 6 radians / second.

[0107] As an example, the Young's modulus (E) of at least one or more intermediate layers can be each in the range of 0.1MPa to 100MPa. As another example, the Young's modulus (E) of the intermediate layer can be about 0.2MPa or more, 0.4MPa or more, 0.6MPa or more, 0.8MPa or more, 1MPa or more, 5MPa or more, or about 10MPa or more, and can be about 95MPa or less, 80MPa or less, 75MPa or less, 70MPa or less, 65MPa or less, 60MPa or less, 55MPa or less, or about 50MPa or less. For example, Young's modulus (E) can be measured in the manner specified in ASTM D882, and can be measured using a device (for example, UTM (universal testing machine)) that can be used to cut the film into a form provided by relevant standards and measure stress-strain curves (force and length can be measured simultaneously). When the Young's modulus of the intermediate layer included in the optical device is within the above range, excellent durability of the optical device can be more advantageously ensured.When the intermediate layer is a laminate of at least two or more sub-intermediate layers, each of the sub-intermediate layers can satisfy the above Young's modulus range.

[0108] As an example, the thermal expansion coefficient of at least one or more intermediate layers can each be 2,000 ppm / K or less. In another example, the thermal expansion coefficient can be about 1,900 ppm / K or less, 1,700 ppm / K or less, 1,600 ppm / K or less, or about 1.500 ppm / K or less, or can be about 10 ppm / K or more, 20 ppm / K or more, 30 ppm / K or more, 40 ppm / K or more, 50 ppm / K or more, 60 ppm / K or more, 70 ppm / K or more, 80 ppm / K or more, 90 ppm / K or more, 100 ppm / K or more, 200 ppm / K or more, 300 ppm / K or more, 400 ppm / K or more, 500 ppm / K or more, 60 ppm / K or more, 700 ppm / K or more, or about 800 ppm / K or more. The thermal expansion coefficient of the intermediate layer can be measured, for example, according to the provisions of ASTM D696, wherein the thermal expansion coefficient can be calculated by cutting it into a form provided by the relevant standard and measuring the length change per unit temperature, and can be measured by known methods such as TMA (thermomechanical analysis). When the thermal expansion coefficient of the intermediate layer included in the optical device is within the above range, the excellent durability of the optical device can be more advantageously ensured. When the intermediate layer is a laminate of at least two or more sub-intermediate layers, each of the sub-intermediate layers can meet the range of the thermal expansion coefficient.

[0109] At least one or more intermediate layers can each be a thermoplastic polyurethane (TPU) adhesive layer, a polyamide adhesive layer, a polyester adhesive layer, an EVA (ethylene vinyl acetate) adhesive layer, an acrylic adhesive layer, a silicone adhesive layer or a polyolefin adhesive layer. According to one example of the present application, at least one or more intermediate layers can each be a thermoplastic polyurethane.

[0110] In an optical device, the outer layer can surround the side of the liquid crystal cell. In an optical device, the top area of ​​the liquid crystal cell can be less than the top area of ​​the first outer substrate or the second outer substrate. In addition, the top area of ​​the liquid crystal cell can be less than the top area of ​​at least one or more intermediate layers included in the optical device. In an example, the liquid crystal cell can be encapsulated by an intermediate layer between the first outer substrate and the liquid crystal cell, an intermediate layer between the second outer substrate and the liquid crystal cell, and an outer layer. In this specification, the term encapsulation can mean covering the entire surface of the liquid crystal cell with an intermediate layer and an outer layer. According to the desired structure, for example, the encapsulation structure can be realized by compressing the laminated body including the first outer substrate, the intermediate layer, the liquid crystal cell, the intermediate layer and the second outer substrate in sequence and including the outer layer surrounding the side of the liquid crystal cell under a vacuum state. The durability and weather resistance of the optical device are greatly improved by such an encapsulation structure, and therefore, it can be stably applied to outdoor applications such as skylights.

[0111] The outer layer may include, for example, a polymer film. In one example, the outer layer may be composed of a polymer film. In another example, the outer layer may be a laminate of two or more polymer films. In the case of a laminate of two or more polymer films, an adhesive layer to which two or more polymer films are attached may also be included. The structure of the outer layer may be appropriately selected within the range of being able to ensure the desired thickness and storage elastic modulus.

[0112] As the polymer film, an appropriate polymer film can be used within the range of the storage elastic modulus that can satisfy Formula 1. As the polymer film, for example, a PC (polycarbonate) film, a PE (polyethylene) film, a TPU (thermoplastic polyurethane), a COP (cycloolefin polymer) film, a POE (polyolefin elastomer) film, an EVA (ethylene vinyl acetate) film, etc. can be used.

[0113] The present application also relates to a method for manufacturing an optical device. The method for manufacturing an optical device may include the following steps: preparing a laminate comprising a first outer substrate, at least one or more intermediate layers, a liquid crystal element, at least one or more intermediate layers, and a second outer substrate in sequence, and autoclaving the laminate. Unless otherwise specified in the method for manufacturing an optical device, the contents described in the optical device may be equally applicable.

[0114] The laminate may further include an outer layer surrounding the side surfaces of the liquid crystal cell.

[0115] When the optical device includes other elements such as a polarizer in addition to the liquid crystal element, the laminate may include the other elements at desired positions in addition to the liquid crystal element.

[0116] The autoclave process may be performed by heating and / or pressurizing the laminate formed after the lamination step.

[0117] The conditions of the autoclave process are not particularly limited, and it can be carried out at a suitable temperature and pressure, for example, according to the type of the intermediate layer applied. The temperature of a typical autoclave process is about 80°C or higher, 90°C or higher, 100°C or higher, and the pressure is 2 atmospheres or higher, but is not limited thereto. The upper limit of the process temperature may be about 200°C or lower, 190°C or lower, 180°C or lower, or 170°C or lower, and the upper limit of the process pressure may be about 10 atmospheres or less, 9 atmospheres or less, 8 atmospheres or less, 7 atmospheres or less, or 6 atmospheres or less.

[0118] Such an optical device can be used in various applications, for example, it can be used in eyewear such as sunglasses or AR (augmented reality) or VR (virtual reality) eyewear, the exterior wall of a building, or a sunroof for a vehicle, etc. In one example, the optical device itself can be a sunroof for a vehicle. For example, in a car including a body having at least one opening formed therein, an optical device or a sunroof for a vehicle attached to the opening can be installed and used.

[0119] Beneficial Effects

[0120] The optical device of the present application can ensure structural stability and good quality uniformity by properly maintaining the cell gap of the liquid crystal element, having excellent adhesion between the upper substrate and the lower substrate, and minimizing defects such as squeezing or aggregation. BRIEF DESCRIPTION OF THE DRAWINGS

[0121] Figure 1 is a cross-sectional view of an exemplary optical device of the present application.

[0122] Figure 2 is a cross-sectional view of an exemplary optical device of the present application.

[0123] Figure 3 is a cross-sectional view of an exemplary liquid crystal element of the present application.

[0124] Figure 4 This is a photograph of the optical device of Comparative Example 1.

[0125] Figure 5This is a microscope image of Comparative Example 1. DETAILED DESCRIPTION

[0126] Hereinafter, the present application will be described in detail through examples, but the scope of the present application is not limited by the following examples.

[0127] Measurement Example 1. Measurement of storage elastic modulus

[0128] The storage elastic modulus was measured using TA's DMA Q800. Specifically, the storage elastic modulus value was recorded in a multi-frequency strain mode under the conditions of a temperature of 25°C, a frequency of 6 rad / sec, a force of 0.01 N, and a heating rate of 3° / min.

[0129] Example 1

[0130] Liquid crystal element manufacturing

[0131] A PET film having a thickness of about 145 μm and a width × height area of ​​900 mm × 600 mm was prepared as the first base layer. ITO (indium tin oxide) was deposited on the first base layer to a thickness of 50 nm to form a first electrode layer. A pressure-sensitive adhesive composition (KR-3700, Shin-Etsu) was bar-coated on the first electrode layer and then dried at about 150 ° C for about 5 minutes to form a pressure-sensitive adhesive layer having a thickness of about 10 μm. The storage modulus of the adhesive layer was about 0.1 MPa. The combination of the first base layer, the first electrode layer and the pressure-sensitive adhesive layer is referred to as an upper substrate.

[0132] As a second base layer, a PET film having a thickness of about 145 μm and a width × height area of ​​900 mm × 600 mm was prepared. On the second base layer, ITO (indium tin oxide) was deposited to a thickness of 50 nm to form a second electrode layer. An acrylic resin composition (KAD-03, Minuta Tech) was coated on the second electrode layer, and then a honeycomb type spacer (partition wall spacer) was formed by photolithography. The pitch of the regular hexagons (closed figures) constituting the honeycomb is about 450 μm, the height is about 6 μm, and the line width is about 30 μm. The area of ​​the closed figure (regular hexagon) formed by the partition wall spacer is about 2.14 mm 2 A vertical alignment film (5661, Nissan chemical) was coated on the spacer to a thickness of about 300 nm and then rubbed in one direction. The combination of the second base layer, the second electrode layer, the spacer, and the vertical alignment film is referred to as a lower substrate.

[0133] A liquid crystal composition is coated on the vertical alignment film of the lower substrate to form a liquid crystal layer, and then the pressure-sensitive adhesive layer of the upper substrate is laminated to form a coating surface facing the liquid crystal composition. The liquid crystal composition comprises a liquid crystal compound (JNC, T12) and a chiral dopant (HCCH, S811), and the pitch (p) of the formed liquid crystal layer is about 20 μm, and the ratio (d / p) of the cell gap (d) to the pitch (p) is about 0.3. The liquid crystal cell is an RTN mode liquid crystal cell in a vertical orientation state when no voltage is applied. The total thickness of the liquid crystal cell is about 306 μm.

[0134] Optical device manufacturing

[0135] A laminate is prepared, the laminate sequentially comprising a first outer substrate, a first intermediate layer, a first polarizer, a second intermediate layer, a prepared liquid crystal cell, a third intermediate layer, a second polarizer, a fourth intermediate layer and a second outer substrate and comprising an outer layer surrounding the side of the liquid crystal cell. Compared with the first outer substrate, the second outer substrate is arranged in the direction of gravity.

[0136] As the first outer substrate, a glass substrate having a thickness of about 3 mm, an area of ​​width × length = 1100 mm × 800 mm, and a radius of curvature of about 2,470R was used. As the second outer substrate, a glass substrate having a thickness of about 3 mm, an area of ​​width × length = 1100 mm × 800 mm, and a radius of curvature of about 2,400R was used. The first polarizer and the second polarizer are each a PVA-based polarizer, which is arranged so that the light transmission axis of the first polarizer and the light transmission axis of the second polarizer form about 90 degrees. The first intermediate layer and the fourth intermediate layer are each a single-layer TPU layer (Argotec), wherein the thickness of one layer is 380 μm. The second intermediate layer and the third intermediate layer are each a laminate of three TPU layers (Argotec), wherein the thickness of one layer is 380 μm. The TPU layer (Argotec) used to form the first intermediate layer to the fourth intermediate layer has a thermal expansion coefficient of 307 ppm / K and a storage elastic modulus of 2.18 MPa. As the outer layer, a PC film (Keiwa) having a storage elastic modulus of 2000 MPa and a thickness of 300 μm was used.

[0137] The laminate is subjected to an autoclave process at a temperature of about 110° C. and a pressure of about 2 atmospheres to produce a Figure 2 The structure of the optical device.

[0138] Example 2

[0139] An optical device was manufactured by performing the process in the same manner as in Example 1, except that a laminate in which two PET films having a storage elastic modulus of about 6,000 MPa in the MD direction, a storage elastic modulus of about 3,000 MPa in the TD direction, and a thickness of 145 μm were attached via a pressure-sensitive adhesive layer (KR-3700, Shin-Etsu) having a storage elastic modulus of about 0.1 MPa and a thickness of 10 μm was used as an outer layer. In Example 2, the total thickness of the outer layer was about 300 μm.

[0140] Example 3

[0141] An optical device was manufactured by performing the process in the same manner as in Example 1, except that a TPU film (Argotec) having a storage elastic modulus of about 100 MPa and a thickness of about 380 μm was used as the outer layer.

[0142] Comparative Example 1

[0143] An optical device was manufactured by performing the process in the same manner as in Example 1, except that a TPU film (Argotec) having a storage elastic modulus of about 100 MPa and a thickness of about 150 μm was used as the outer layer.

[0144] Comparative Example 2

[0145] An optical device was manufactured by performing the process in the same manner as in Example 1, except that a laminate of a TPU film (Argotec) having a storage elastic modulus of about 100 MPa and a thickness of about 380 μm and a TPU film (Argotec) having a storage elastic modulus of about 100 MPa and a thickness of about 150 μm was used as the outer layer. In Comparative Example 2, the total thickness of the outer layer was about 530 μm.

[0146] Evaluation Example 1. Evaluation of Lamination Process Defects

[0147] In the optical devices manufactured in Example 1 and Comparative Example 1, it was observed whether extrusion and aggregation defects occurred in a state where no voltage was applied. In Example 1, no extrusion defects and aggregation defects were observed, but in Comparative Example 1, extrusion and aggregation defects were observed, such as Figure 4 and Figure 5 shown. Figure 4 This is a camera photograph of the optical device of Comparative Example 1. Figure 5 is a microscope image of the optical device of Comparative Example 1. Figure 4 As shown in red (shown on the left), since the concentration of the dichroic dye is higher than that of the peripheral area, the agglomerated defect area appears darker than the peripheral area, and as shown in FIG. Figure 4As shown in medium green (shown on the right), the extrusion defect area appears brighter than the peripheral area because the concentration of the dichroic dye is lower than that of the peripheral area. In Comparative Example 2, the glass substrate was damaged during the lamination process. Figure 5 (A) shows the extrusion defect of Comparative Example 1, Figure 5 (B) shows the aggregated defects of Comparative Example 1.

[0148] [Explanation of Reference Numerals]

[0149] 100a: first outer substrate, 100b: second outer substrate, 200a, 200b, 200c, 200d: intermediate layer, 300: liquid crystal element, 400: outer layer, 500a: first polarizer, 500b: second polarizer, 10a: first base layer, 10b: first electrode layer, 10c: pressure-sensitive adhesive layer, 20a: second base layer, 20b: second electrode layer, 20c: spacer, 20d: alignment film.

Claims

1. An optical device, comprising a first outer substrate, a second outer substrate disposed opposite to the first outer substrate, a liquid crystal cell, an outer layer surrounding the side of the liquid crystal cell, and at least one intermediate layer respectively located between the first outer substrate and the liquid crystal cell and between the liquid crystal cell and the second outer substrate, wherein The liquid crystal element and the outer layer are present between the first outer substrate and the second outer substrate, The liquid crystal element includes a first base layer, a pressure-sensitive adhesive layer formed on an inner side of the first base layer, a second base layer disposed opposite to the first base layer, a spacer formed on an inner side of the second base layer, and a liquid crystal layer located between the first base layer and the second base layer, The storage elastic modulus G1 of the outer layer at 25° C. is in the range of 100 MPa to 10,000 MPa and the storage elastic modulus of the intermediate layer at 25° C. is 80 MPa or less, and The optical device satisfies the following formula 1: [Formula 1] -T2×0.4≤T1-T2≤T2×0.4 in, T1 is the thickness of the outer layer, and T2 is the thickness of the liquid crystal element. 2 . The optical device according to claim 1 , wherein a thickness T1 of the outer layer is in the range of 60 μm to 840 μm.

3. The optical device according to claim 1, satisfying the following formula 2: [Formula 2] G1≥G2 in, G1 is the storage elastic modulus of the outer layer at a temperature of 25° C. and a frequency of 6 rad / sec, and G2 is the storage elastic modulus of the pressure-sensitive adhesive layer at a temperature of 25° C. and a frequency of 6 rad / sec.

4. The optical device according to claim 1, wherein a difference G1-G2 between a storage elastic modulus G1 of the outer layer at a temperature of 25°C and a frequency of 6 rad / s and a storage elastic modulus G2 of the pressure-sensitive adhesive layer at a temperature of 25°C and a frequency of 6 rad / s is in a range of 0 MPa to 9999.99 MPa. The optical device of claim 1 , wherein the outer layer comprises a polymer film. 6 . The optical device according to claim 1 , wherein the liquid crystal layer is switched between a first alignment state and an alignment state different from the first alignment state by application of external energy. 7 . The optical device according to claim 1 , wherein the spacer is a patterned spacer that maintains a gap between the first base layer and the second base layer. 8 . The optical device according to claim 1 , wherein a ratio B / A of an area B of the spacer to an area A of the second base layer is in a range of 5% to 50%.

9. An optical device according to claim 1, wherein the liquid crystal element further comprises a first electrode layer formed on an inner surface of the first base layer and a second electrode layer formed on an inner surface of the second base layer, wherein the pressure-sensitive adhesive layer is present on the inner surface of the first electrode layer, and the spacer is present on the inner surface of the second electrode layer. 10 . The optical device according to claim 9 , wherein the liquid crystal element further includes an alignment film present on an inner surface of the second electrode layer, wherein no alignment film is included on an inner surface of the first base layer.

11. The optical device according to claim 1, wherein the liquid crystal element is encapsulated by the intermediate layer and the outer layer. 12 . The optical device according to claim 1 , wherein a sum of total thicknesses of the at least one intermediate layer is 800 μm or more.

13. The optical device of claim 1, wherein the at least one intermediate layer is a thermoplastic polyurethane adhesive layer, a polyamide adhesive layer, a polyester adhesive layer, an ethylene vinyl acetate adhesive layer, an acrylic adhesive layer, a silicone adhesive layer, or a polyolefin adhesive layer.

14. A car, comprising: a vehicle body having one or more openings formed therein; and the optical device according to claim 1 mounted in the opening.

Images