Optical Modulation Devices

Abstract

The present application can provide a light modulation device and use thereof. The present application can provide a light modulation device and use thereof that can stably maintain the alignment of a liquid crystal compound while securing adhesion between opposing substrates by applying a pressure-sensitive adhesive layer or an adhesive layer, and can particularly stably maintain or realize a desired alignment state of a liquid crystal compound for a long period of time even at high temperatures.

Description

[Technical field]

[0001] The present invention relates to an optical modulation device and its applications. [Background technology]

[0002] 2. Description of the Related Art Light modulation devices having a light modulation layer containing a liquid crystal compound or the like disposed between two substrates are used for a variety of purposes.

[0003] In order for the light modulation device to exhibit the desired performance, it is important to control the alignment state of the liquid crystal compound between the substrates. Therefore, when the light modulation layer is a liquid crystal layer, liquid crystal alignment films are usually formed on both sides of the liquid crystal layer to adjust the alignment of the liquid crystal compound.

[0004] Patent Document 1 discloses a light modulation device having a structure in which a liquid crystal alignment film is formed on one side of a liquid crystal layer, and an adhesive layer is formed on the other side instead of the liquid crystal alignment film.

[0005] It is noted that the adhesive layer disclosed in Patent Document 1 has a liquid crystal aligning force, and therefore it is possible to achieve the desired alignment of liquid crystal compounds without applying a liquid crystal alignment film to one side of the liquid crystal layer.

[0006] The optical modulation device disclosed in Patent Document 1 has an advantage in that an adhesive is applied to one of the substrates, so that the adhesive strength between the two substrates arranged opposite to each other can be excellently maintained.

[0007] However, it is difficult to maintain the alignment of the liquid crystal compound sufficiently stably using only the adhesive layer disclosed in Patent Document 1, and there is a problem that the alignment of the liquid crystal compound is broken under high temperature conditions in particular, resulting in optical defects. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Korean Patent No. 1987373 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention provides an optical modulation device that uses a pressure-sensitive adhesive layer or an adhesive layer to ensure adhesion between opposing substrates and simultaneously stably maintain the alignment of liquid crystal compounds, and in particular, can stably maintain or realize a desired alignment state of liquid crystal compounds for a long period of time even at high temperatures. [Means for solving the problem]

[0010] In this specification, the terms vertical, parallel, orthogonal, or horizontal and the numerical values ​​of the angles used to define the angles refer to substantially vertical, parallel, orthogonal, or horizontal and the numerical values ​​as long as the intended effect is not impaired. The ranges of the vertical, parallel, orthogonal, or horizontal values ​​include errors such as manufacturing errors or variations. For example, each of the above cases may include an error within about ±3 degrees, an error within about ±2 degrees, an error within about ±1 degree, an error within about ±0.8 degrees, an error within about ±0.6 degrees, or an error within about ±0.4 degrees.

[0011] In the present specification, when the measurement temperature affects the physical property, the physical property is measured at room temperature unless otherwise specified. The term "room temperature" refers to a temperature in a state where the temperature is not particularly increased or decreased, and may mean any one temperature within a range of about 10°C to 30°C, for example, a temperature of about 15°C or more, 18°C ​​or more, 20°C or more, or about 23°C or more, and about 27°C or less. In addition, unless otherwise specified, the unit of temperature referred to in the present specification is °C.

[0012] Unless otherwise specified, an angle between any two directions referred to in this specification may be an acute angle between the acute and obtuse angles between the two directions, or a smaller angle between angles measured clockwise and counterclockwise. Thus, unless otherwise specified, angles referred to in this specification are positive numbers. However, in some cases, in order to indicate a measurement direction between angles measured clockwise or counterclockwise, one of the angles measured clockwise and the angle measured counterclockwise may be expressed as a positive number and the other angle may be expressed as a negative number.

[0013] Unless otherwise specified in this specification, the reference wavelength for the transmittance, refractive index, in-plane retardation, thickness direction retardation, and the like is about 550 nm.

[0014] In this application, the term "light modulation device" may refer to an element that can switch between at least two or more different light states, where the different light states may refer to states with different transmittances, for example.

[0015] Examples of states that the light modulating device can realize include a transmission mode and a blocking mode. As one example, the light modulating device of the present application may be an element that can be switched between at least the transmission mode and the blocking mode.

[0016] The transmittance of the light modulation device in the transmission mode may be at least 10%, 12%, 14%, 16%, 18%, 20%, 22%, or 24%. The transmittance in the transmission mode may be, for example, 100% or less, 95% or less, 90% or less, 85% or less, 80% or less, 75% or less, 70% or less, 65% or less, 60% or less, 55% or less, 50% or less, 45% or less, 40% or less, 35% or less, or about 30% or less. However, since the higher the transmittance in the transmission mode, the more advantageous it is, the upper limit is not particularly limited.

[0017] The transmittance of the light modulation device in the blocking mode state may be 10% or less, 9% or less, 8% or less, 7% or less, 6% or less, 5% or less, 4% or less, 3% or less, 2% or less, 1% or less, 0.8% or less, 0.6% or less, 0.4% or less, or 0.2% or less. In other examples, the transmittance in the blocking mode may be 0% or more or about 0.1% or more. However, since a lower transmittance is more advantageous in the blocking mode, the lower limit of the transmittance in the blocking mode state is not particularly limited.

[0018] The transmittance may be, for example, a straight light transmittance. The straight light transmittance is a percentage of the ratio of the light transmitted in the same direction as the incident direction to the light incident on the element. For example, if the element is in the form of a film or sheet, the transmittance can be defined as the percentage of the light transmitted through the element in the direction aligned with the normal direction of the film or sheet surface out of the light incident in the direction aligned with the normal direction.

[0019] The transmittance may be the transmittance for any one wavelength in the visible light region, for example, within a range of about 400 to 700 nm or about 380 to 780 nm, the transmittance for the entire visible light region, the maximum or minimum transmittance among the transmittances for the entire visible light region, or the average value of the transmittances in the visible light region.

[0020] In another example, the transmittance may be the transmittance for light having a wavelength of about 550 nm.

[0021] The light modulation device of the present application may be designed to be capable of switching between at least two or more states, including any one of the transmission and blocking mode states and another state, and may also be embodied, if necessary, in addition to the above states, for example, a third state or more states including a state of intermediate transmittance between the transmission and blocking mode states.

[0022] The switching of the light modulating device may be controlled by the application of an external signal, e.g., an electrical signal. For example, in the absence of an external signal, such as a voltage, the light modulating device may maintain one of the above-mentioned states, and may switch to another state when a voltage is applied. By changing the magnitude, frequency and / or form of the applied voltage, the mode state may also be changed or a third other mode state may be realized.

[0023] The light modulation device in the present application may include two substrates arranged opposite to each other and a variable transmittance layer located between the substrates. FIG. 2 is a diagram showing an example of the structure. As shown in the figure, the light modulation device includes a first substrate 100 and a second substrate 200 arranged opposite to each other. The first and second substrates may have a first surface and a second surface, respectively. The first surface may refer to one of the main surfaces of the substrate, and the second surface may refer to the main surface opposite to the first surface.

[0024] As shown in FIG. 2, a functional layer 1001 may be formed on one surface (e.g., referred to as the first surface) of the first substrate 100, and a liquid crystal alignment film 2001 may be formed on one surface (e.g., referred to as the first surface) of the other second substrate 200. The functional layer may be a silicone polymer layer described later. A transmittance variable layer 600 is located between the first substrate 100 and the second substrate 200 disposed opposite to each other. There is no particular limitation on the type of the transmittance variable layer, and a liquid crystal layer may be used as the transmittance variable layer. When the transmittance variable layer is a liquid crystal layer, a liquid crystal alignment film is generally formed on both sides of the first and second substrates 100 and 200. However, a silicone polymer layer described later is formed on the first substrate 100 instead of the liquid crystal alignment film, and a liquid crystal alignment film is formed only on the second substrate 200, thereby obtaining an alignment state of liquid crystal compounds that is very useful for specific applications (e.g., smart windows, sunroofs, and eyewear). In such a case, a liquid crystal alignment film is not formed on the first substrate. Although not shown in the drawing, one of the first and second substrates of the optical modulation device has a spacer that maintains the cell gap between the first and second substrates. If the functional layer 1001 on the first substrate 100 can function as an adhesive layer or glue layer 1001, the adhesive layer or glue layer 1001 can be attached to the spacer to greatly improve the adhesion between the first and second substrates.

[0025] Thus, in one example, the light modulation device of the present application may include first and second substrates arranged opposite each other; a liquid crystal layer present between the first and second substrates, and a silicone polymer layer may be present between the first substrate and the liquid crystal layer as the functional layer.

[0026] The substrate may be made of any known substrate material without any particular limitation. For example, the substrate may be made of an inorganic film such as a glass film, a crystalline or amorphous silicone film, a quartz film, or an ITO (Indium Tin Oxide) film, or a plastic film. The plastic film may be made of a substrate including, but not limited to, TAC (triacetyl cellulose); norbornene derivative substrate, COP (cyclo olefin copolymer); PMMA (poly(methyl methacrylate); PC (polycarbonate); PE (polyethylene); PP (polypropylene); PVA (polyvinyl alcohol); DAC (diacetyl cellulose); Pac (Polyacrylate); PES (poly ether sulfone); PEEK (polyetheretherketon); PPS (polyphenylsulfone), PEI (polyetherimide); PEN (polyethylenenaphthalate); PET (polyethyleneterephtalate); PI (polyimide); PSF (polysulfone); PAR (polyarylate), or an amorphous fluororesin. The thickness of the substrate may be selected within an appropriate range without any particular limitation.

[0027] In one example, the substrate may be an optically anisotropic film. Such an optically anisotropic film usually has anisotropic mechanical properties, and by utilizing such anisotropy, a light modulation device having superior durability can be provided.

[0028] In one example, the anisotropic film may have an in-plane retardation of about 500 nm or more. The in-plane retardation is a value for light with a wavelength of 550 nm, and is a physical quantity defined by the following mathematical formula A. Other examples of the in-plane retardation of the retardation film include 600 nm or more, 700 nm or more, 800 nm or more, 900 nm or more, 1,000 nm or more, 1,100 nm or more, 1,200 nm or more, 1,300 nm or more, 1,400 nm or more, 1,500 nm or more, 2,000 nm or more, 2,500 nm or more, 3,000 nm or more, 3,500 nm or more, 4,000 nm or more, 4,500 nm or more, 5,000 nm or more, 5,500 nm or more, 6,000 nm or more, 6,500 nm or more, 7,000 nm or more, 7,500 nm or more, 8,000 nm or more, 8,500 nm or more, 9,000 nm or more, or 9,500 nm or more. or may be about 100,000nm or less, 90,000nm or less, 80,000nm or less, 70,000nm or less, 60,000nm or less, 50,000nm or less, 40,000nm or less, 30,000nm or less, 20,000nm or less, 15,000nm or less, 14,000nm or less, 13,000nm or less, 12,000nm or less, 10,000nm or less, 9,500nm or less, 9,000nm or less, 8,500nm or less, 8,000nm or less, 7,500nm or less, 7,000nm or less, 6,500nm or less, 6,000nm or less, 5,500nm or less, 5,000nm or less, or 4,500nm or less.

[0029] The specific type of the film that can be applied to the substrate is not particularly limited as long as it shows the in-plane retardation in the range mentioned above. For example, an anisotropic polymer film that is given optical anisotropy by stretching can be applied. Examples of the polymer film include polyolefin films such as polyethylene films or polypropylene films, cycloolefin polymer (COP) films such as polynorbornene films, polyvinyl chloride films, polyacrylonitrile films, polysulfone films, polyacrylate films, cellulose ester polymer films such as PVA (poly(vinyl alcohol)) films or TAC (Triacetyl cellulose) films, polyester films or polycarbonate films, and copolymer films of two or more monomers among the monomers that form the polymers.

[0030] As one example, the film may be a polyester film such as a PET (poly(ethylene terephthalate)) film. That is, films exhibiting an in-plane retardation in the above-mentioned range are well known in the industry, and in the case of polymer films, such films exhibit not only large optical anisotropy but also asymmetric mechanical properties due to stretching during the manufacturing process. A representative example of such retardation films that are well known in the industry is a stretched polyester film such as a stretched PET (poly(ethylene terephthalate)) film.

[0031] As an example, the film may be a polyester film such as a PET film, but the type of film applicable to the substrate in the present application is not limited thereto.

[0032] The in-plane retardation is a physical quantity determined by the following formula A.

[0033] [Formula A] R in =d×(n x-n y )

[0034] In formula A, R in is the in-plane retardation, and n x is the refractive index of the film in the slow axis direction, and n y is the refractive index in the fast axis direction of the film, and d is the thickness of the film. The meanings of the slow axis and fast axis in the above are well known in the industry.

[0035] When the anisotropic film is applied simultaneously to a first and second substrate, the substrates may be arranged such that their slow axes are parallel or perpendicular to each other.

[0036] The light modulation device may include at least a variable transmittance layer for the switching. In one example, the variable transmittance layer may be a layer that generates polarized light components. An example of such a variable transmittance layer is an active liquid crystal layer.

[0037] The term "active liquid crystal layer" may refer to a liquid crystal layer that includes at least a liquid crystal compound and in which the alignment state of the liquid crystal compound can be controlled by applying an external signal, etc. However, the application of an active liquid crystal layer is only one example of the present application, and other known transmittance variable layers, for example, an electrochromic material layer, a photochromic material layer, an electrophoretic material layer, or a dispersed particle alignment layer, may be used as necessary.

[0038] The active liquid crystal layer is a layer containing a liquid crystal compound. In this specification, the term "active liquid crystal layer" includes all layers containing a liquid crystal compound whose alignment can be controlled by applying an external signal, and for example, as described below, a so-called guest-host layer containing a liquid crystal compound (liquid crystal host) and a dichroic dye is also a type of liquid crystal layer defined in this specification. As the liquid crystal compound, any type of liquid crystal compound can be used as long as the alignment direction can be changed by applying an external signal. For example, the liquid crystal compound can be a smectic liquid crystal compound, a nematic liquid crystal compound, a cholesteric liquid crystal compound, or the like. In addition, the liquid crystal compound may be, for example, a compound without a polymerizable group or a crosslinkable group so that the alignment direction can be changed by applying an external signal.

[0039] The liquid crystal layer may include a liquid crystal compound having a positive or negative dielectric anisotropy. The absolute value of the dielectric anisotropy of the liquid crystal may be appropriately selected in consideration of the object of the present application. The term "dielectric anisotropy (Δε)" may mean the difference (εp-εv) between the horizontal dielectric constant (εp) and the vertical dielectric constant (εv) of the liquid crystal. In addition, the term "horizontal dielectric constant (εp)" in this specification means a dielectric constant value measured along the direction of an electric field in a state where a voltage is applied so that the direction of the electric field caused by the applied voltage is substantially horizontal to the director of the liquid crystal molecules, and the term "vertical dielectric constant (εv)" means a dielectric constant value measured along the direction of the electric field in a state where a voltage is applied so that the direction of the electric field caused by the applied voltage is substantially perpendicular to the director of the liquid crystal molecules.

[0040] For example, the refractive index anisotropy (Δn) of the liquid crystal layer may be in the range of 0.01 to 0.5. In other examples, the refractive index anisotropy may be 0.02 or more, 0.03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.07 or more, 0.08 or more, or 0.085 or more, or may be about 0.45 or less, 0.4 or less, 0.35 or less, 0.3 or less, 0.25 or less, 0.2 or less, 0.15 or less, or 0.1 or less. The refractive index anisotropy of the liquid crystal layer is selected depending on the purpose, and is not limited by the above.

[0041] Examples of driving modes of the liquid crystal layer include DS (Dynamic Scattering) mode, ECB (Electrically Controllable Birefringence) mode, IPS (In-Plane Switching) mode, FFS (Fringe-Field Switching) mode, OCB (Optially Compensated Bend) mode, VA (Vertical Alignment) mode, MVA (Multi-domain Vertical Alignment) mode, PVA (Patterned Vertical Alignment) mode, HAN (Hybrid Aligned Nematic) mode, TN (Twisted Nematic) mode, STN (Super Twisted Nematic) mode, and R-TN (Reversed Twisted Nematic) mode.

[0042] The liquid crystal layer of the present application may be designed (formed) to realize at least a twisted alignment among the above modes. The twisted alignment refers to a state in which the liquid crystal compound in the liquid crystal layer is aligned in a twisted form based on a virtual helical axis, and such a twisted alignment may be realized when the liquid crystal compound in the liquid crystal layer is aligned horizontally, vertically, tilted, or splayed. The twisted alignment may be realized in the initial state of the liquid crystal layer, or when an external signal is applied.

[0043] In one embodiment, the liquid crystal layer may be designed (formed) to be switchable between at least a homeotropic alignment state and a twisted alignment state, for example, by initially implementing one of the two states, or by applying an external signal (e.g., an electrical signal such as a voltage) to switch to the other state.

[0044] In one example, the initial state may be a vertical alignment state.

[0045] The light modulation device of the present application can be designed so that the alignment state of the liquid crystal layer (particularly the vertical alignment state) is stably maintained even at high temperatures.

[0046] For example, in a light modulation device including the first and second substrates and a liquid crystal layer present between the first and second substrates, the absolute value of ΔT in the following formula 1 may be within a predetermined range.

[0047] [Formula 1]

number

[0048] In Equation 1, T 2 is the transmittance measured at 90° C. with the light modulating device placed between two crossed polarizers after maintaining the light modulating device at 90° C. for 5 minutes. In Equation 1, T 1 is the transmittance measured at 25° C. when the light modulation device was placed between two crossed polarizers before being maintained at 90° C. for 5 minutes.

[0049] The T in formula 1 1 and T 2 is the transmittance measured when the liquid crystal layer of the light modulation device is in a vertically aligned state, and the liquid crystal layer is in a vertically aligned state during the process of maintaining the light modulation device at 90° C. for 5 minutes.

[0050] T in Eq. 1 and T 2 The unit of is %, and this is a value evaluated by the method described in the Examples section below.

[0051] FIG. 1 and T 2 FIG. 13 is a diagram showing a process of checking the above.

[0052] As shown in FIG. 1, when the optical modulation device 200 is placed between two orthogonal polarizers 101 and 102, the transmittance T 1 and T 2The transmittance is measured on the side of the other polarizer 102 after light is incident on the side of one of the two orthogonal polarizers 101 and 102 (in the direction of the arrow in FIG. 1), as shown in FIG. 1. The measurement of the incidence of light and the transmittance is performed in a direction parallel to the normal direction of the surfaces of the orthogonal polarizers 101 and 102.

[0053] The orthogonal polarizers mentioned above refer to a state in which the optical absorption axes of two orthogonal polarizers 101 and 102 are perpendicular to each other. In general, when the optical absorption axis of one of the two polarizers is fixed and the optical absorption axis of the other polarizer is rotated with respect to the optical absorption axis, the point at which the lowest transmittance appears is determined as the point at which the optical absorption axes of the two polarizers are perpendicular to each other. 1 and T 2 In the process of measuring, if the first and / or second substrate of the optical modulation device is an anisotropic substrate, the slow axis of the substrate is arranged parallel to the optical absorption axis of one of the two polarizers.

[0054] When the liquid crystal layer is vertically aligned, as shown in Figure 1, if the liquid crystal layer is placed between two crossed polarizers and the transmittance is measured, the transmittance is measured as low. However, if the vertical alignment of the liquid crystal layer is damaged or deteriorated during a certain period of time at high temperature (90°C for 5 minutes) while the liquid crystal layer is vertically aligned, the transmittance measured above will be low. 2 is T 1 will appear higher than

[0055] However, in the light modulation device of the present application, since the alignment (particularly the vertical alignment) of the liquid crystal layer can be stably maintained even at high temperatures, the absolute value of ΔT may be at or below a certain level. For example, the absolute value of ΔT may be 300% or less, 290% or less, 280% or less, 270% or less, 260% or less, 250% or less, 240% or less, 230% or less, 220% or less, 210% or less, 200% or less, 190% or less, 180% or less, 170% or less, 160% or less, 150% or less, 140% or less, 130% or less, 120% or less, 110% or less, 100% or less, It may be about 95% or less, 90% or less, 85% or less, 80% or less, 75% or less, 70% or less, 65% or less, 60% or less, 55% or less, 50% or less, 45% or less, 40% or less, 35% or less, 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, 5% or less, 4% or less, 3% or less, 2% or less, 1% or less, or 0.5% or less, or may be substantially 0%. The absolute value of ΔT may be about 0% or more, 0.5% or more, 1% or more, 1.5% or more, 2% or more, 2.5% or more, 3% or more, 3.5% or more, 4% or more, 4.5% or more, 5% or more, 5.5% or more, 6% or more, 6.5% or more, 7% or more, 7.5% or more, 8% or more, 8.5% or more, 9% or more, 9.5% or more, or 10% or more. The absolute value of ΔT may be within a range between any one of the above-mentioned lower limits and any one of the above-mentioned upper limits.

[0056] Said T 2 The specific value of is not particularly limited, but may be, for example, about 2% or less. 2 In other examples, T may be about 1.8% or less, 1.6% or less, 1.4% or less, 1.2% or less, 1% or less, 0.8% or less, 0.6% or less, 0.4% or less, or 0.2% or less. 2 There is no lower limit for T 2 may be 0% or more.

[0057] Said T 1 and T 2 The method for measuring the above will be specifically described in the Examples.

[0058] The transmittance variable layer, which is a liquid crystal layer, basically contains the liquid crystal compound, and may contain additional components, if necessary.

[0059] For example, the liquid crystal layer, which is a transmittance variable layer, may contain a so-called chiral dopant together with the liquid crystal compound. Such a chiral dopant can induce a helical structure orientation, i.e., the twisted orientation, in the liquid crystal compound.

[0060] The chiral dopant can be used without any particular limitation as long as it can induce the desired twisting without damaging the liquid crystal property, for example, the nematic regularity. The chiral dopant for inducing the rotation of the liquid crystal molecules must at least include chirality in the molecular structure. Examples of the chiral dopant include a compound having one or more asymmetric carbons, a compound having an asymmetric point on a heteroatom such as a chiral amine or a chiral sulfoxide, or a compound having an axially asymmetric, optically active site such as cumulene or binaphthol. The chiral dopant may be, for example, a low molecular weight compound having a molecular weight of 1,500 or less. As the chiral dopant, a commercially available chiral nematic liquid crystal, for example, a commercially available chiral dopant liquid crystal S811 manufactured by Merck or LC756 manufactured by BASF, etc., can be used.

[0061] The ratio of the chiral dopant is not particularly limited, but the chiral dopant may be added so that the ratio (d / p) of the thickness of the light modulation layer (d, cell gap) and the pitch (p) of the helical structure of the liquid crystal compound generated by the addition of the chiral dopant (the pitch of the twisted orientation) satisfies the K value described below.

[0062] The pitch (p) of the so-called twisted light modulation layer (liquid crystal layer) to which the chiral dopant is applied can be measured by a measurement method using a wedge cell, and can be measured by the method described in Simple method for accurate measurements of the cholesteric pitch using a stripe-wedge Grandjean-Cano cell by D. Podolskyy et al. (Liquid Crystals, Vol. 35, No. 7, July 8, 2008, 789-791). The content (wt%) of the chiral dopant is calculated by the formula 100 / (HTP (Helixcal Twisting power) x pitch (nm), and can be selected at an appropriate ratio taking into account the desired pitch (p).

[0063] The liquid crystal layer may be designed such that the ratio (d / p) of the pitch (p) of the twisted orientation to the thickness (d, cell) of the light modulation layer (liquid crystal layer) is less than 1. In other examples, the ratio (d / p) may be 0.95 or less, 0.9 or less, 0.85 or less, 0.8 or less, 0.75 or less, 0.7 or less, 0.65 or less, 0.6 or less, 0.55 or less, 0.5 or less, 0.45 or less, 0.4 or less, 0.35 or less, 0.3 or less, 0.25 or less, or 0.2 or less, or may be about 0.1 or more, 0.15 or more, 0.2 or more, 0.25 or more, 0.3 or more, 0.35 or more, 0.4 or more, 0.45 or more, or 0.5 or more.

[0064] The liquid crystal layer may be designed so that the pitch (p) of the twisted orientation is within the range of 1 to 100 μm. In other examples, the ratio may be 2 μm or more, 3 μm or more, 4 μm or more, 5 μm or more, 6 μm or more, 7 μm or more, 8 μm or more, 9 μm or more, 10 μm or more, 11 μm or more, 12 μm or more, 13 μm or more, 14 μm or more, 15 μm or more, 16 μm or more, 17 μm or more, 18 μm or more, 19 μm or more, or 19.5 μm or more, or 95 μm or less, 90 μm or less, 85 μm or less, 80 μm or less, 75 μm or less, 70 μm or less, 65 μm or less, 60 μm or less, 55 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, or 25 μm or less.

[0065] The thickness (d, cell gap) of the liquid crystal layer may be in the range of 0.5 μm to 50 μm. Other examples of the gap) may be 1 μm or more, 1.5 μm or more, 2 μm or more, 2.5 μm or more, 3 μm or more or 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, 9.5 μm or more, or 10 μm or more, or may be 48 μm or less, 46 μm or less, 44 μm or less, 42 μm or less, 30 μm or less, 38 μm or less, 36 μm or less, 34 μm or less, 32 μm or less, 30 μm or less, 28 μm or less, 26 μm or less, 24 μm or less, 22 μm or less, 20 μm or less, 18 μm or less, 16 μm or less, 14 μm or less, 12 μm or less, or 10 μm or less.

[0066] Through the above design, an optical modulation device can be provided that can more efficiently achieve the objectives of the present application.

[0067] The transmittance variable layer (liquid crystal layer) may contain other necessary additional components (for example, a dichroic dye, etc.).

[0068] In such a light modulation device, a silicone polymer layer may be present between the first substrate and the liquid crystal layer. The term "silicone polymer layer" refers to a layer containing silicone polymer at 50% or more, 55% or more, 60% or more, 65% or more, 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more by weight. The upper limit of the proportion of silicone polymer in the silicone polymer layer may be 100% or less or less than 100%.

[0069] The silicone polymer layer may be formed directly on the surface of the first substrate facing the liquid crystal layer, or other layers (e.g., an electrode layer described below) may be present between the first substrate and the silicone polymer layer.

[0070] In one example, the silicone polymer layer may be a so-called adhesive layer or pressure sensitive adhesive layer.

[0071] The silicone polymer layer may be formed on the surface of the first substrate. Such a silicone polymer layer may be formed to have an area of ​​70% or more of the entire area of ​​the first substrate. The area of ​​the silicone polymer layer may be about 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more of the entire area of ​​the first substrate. There is no particular upper limit to the area of ​​the silicone polymer layer, and it may be, for example, about 100% or less or less than 100% of the entire area of ​​the first substrate.

[0072] A silicone polymer layer as described above may be included in the light modulating device in contact with the liquid crystal layer.

[0073] The material forming the silicone polymer layer is not particularly limited. In one example, when the silicone polymer layer is an adhesive layer or a pressure-sensitive adhesive layer, a silicone pressure-sensitive adhesive layer or a silicone adhesive layer can be applied to the silicone polymer layer. For example, there are various types of silicone-based adhesives or silicone-based adhesives known in the industry as OCA (Optically Clear Adhesive) or OCR (Optical Clear Resin), and such adhesives or adhesives can induce suitable alignment of liquid crystal compounds by combining with a liquid crystal alignment film in a state containing a compound described below.

[0074] The unique surface properties of the silicone polymer layer can induce an alignment state of liquid crystal compounds suitable for a purpose in combination with a liquid crystal alignment film (particularly a vertical alignment film).

[0075] The silicone-based adhesive or adhesive may be a cured product of a curable silicone adhesive or adhesive composition (hereinafter, simply referred to as a curable silicone composition). The type of the curable silicone composition is not particularly limited, and for example, a heat-curable silicone composition may be used.

[0076] In one example, the curable silicone composition may contain, as an addition curable silicone composition, (1) a polyorganosiloxane containing two or more alkenyl groups in the molecule and (2) a polyorganosiloxane containing two or more silicon-bonded hydrogen atoms in the molecule. The silicone compound may form a cured product by addition reaction in the presence of a catalyst such as a platinum catalyst.

[0077] The (1) polyorganosiloxane contains at least two alkenyl groups in one molecule as a main component constituting a silicone cured product. Specific examples of the alkenyl group include vinyl, allyl, butenyl, pentenyl, hexenyl, and heptenyl groups, among which vinyl groups are usually used, but are not limited thereto. In the (1) polyorganosiloxane, the bonding position of the alkenyl group is not particularly limited. For example, the alkenyl group may be bonded to the end of the molecular chain and / or to the side chain of the molecular chain. In the (1) polyorganosiloxane, examples of the types of substituents that may be contained in addition to the alkenyl include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups such as benzyl and phenethyl; and halogen-substituted alkyl groups such as chloromethyl, 3-chloropropyl, and 3,3,3-trifluoropropyl. Of these, methyl and phenyl groups are usually used, but are not limited thereto.

[0078] The molecular structure of the (1) polyorganosiloxane is not particularly limited, and may have any shape, such as linear, branched, cyclic, network, or partially branched linear, etc. Usually, among the molecular structures described above, those having a linear molecular structure are particularly used, but are not limited thereto.

[0079] More specific examples of the (1) polyorganosiloxane include dimethylsiloxane-methylvinylsiloxane copolymers capped at both molecular chain terminals with trimethylsiloxane groups, methylvinylpolysiloxanes capped at both molecular chain terminals with trimethylsiloxane groups, dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane copolymers capped at both molecular chain terminals with trimethylsiloxane groups, dimethylpolysiloxanes capped at both molecular chain terminals with dimethylvinylsiloxane groups, methylvinylpolysiloxanes capped at both molecular chain terminals with dimethylvinylsiloxane groups, dimethylsiloxane-methylvinylsiloxane copolymers capped at both molecular chain terminals with dimethylvinylsiloxane groups, dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane copolymers capped at both molecular chain terminals with dimethylvinylsiloxane groups, R 1 2 SiO 2 / 2 Siloxane units represented by and R 1 2 R 2 SiO 1 / 2 The siloxane unit represented by and SiO 4 / 2 Polyorganosiloxane copolymers containing siloxane units represented by R 1 2 R 2 SiO 1 / 2 The siloxane unit represented by and SiO 4 / 2 Polyorganosiloxane copolymers containing siloxane units represented by R 1 R 2 SiO 2 / 2 Siloxane units represented by and R 1 SiO 3 / 2 Siloxane units represented by R 2 SiO 3 / 2 Examples of the polyorganosiloxane copolymers include, but are not limited to, polyorganosiloxane copolymers containing siloxane units represented by the formula: 1is a hydrocarbon group other than an alkenyl group, specifically, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, or a heptyl group; an aryl group such as a phenyl group, a tolyl group, a xylyl group, or a naphthyl group; an aralkyl group such as a benzyl group or a phenethyl group; or a halogen-substituted alkyl group such as a chloromethyl group, a 3-chloropropyl group, or a 3,3,3-trifluoropropyl group. 2 is an alkenyl group, and specifically may be a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, or the like.

[0080] The molecular structure of the (2) polyorganosiloxane is not particularly limited, and may have any shape, such as linear, branched, cyclic, network, or partially branched linear, etc. Among the molecular structures described above, those having a linear molecular structure are usually applied, but are not limited thereto.

[0081] More specific examples of the (2) polyorganosiloxane include methylhydrogenpolysiloxanes capped with trimethylsiloxane groups at both molecular chain terminals, dimethylsiloxane-methylhydrogen copolymers capped with trimethylsiloxane groups at both molecular chain terminals, dimethylsiloxane-methylhydrogensiloxane-methylphenylsiloxane copolymers capped with trimethylsiloxane groups at both molecular chain terminals, dimethylpolysiloxanes capped with dimethylhydrogensiloxane groups at both molecular chain terminals, dimethylsiloxane-methylphenylsiloxane copolymers capped with dimethylhydrogensiloxane groups at both molecular chain terminals, methylphenylpolysiloxanes capped with dimethylhydrogensiloxane groups at both molecular chain terminals, R 1 3 SiO 1 / 2 The siloxane unit represented by R 1 2 HSiO 1 / 2 The siloxane unit represented by and SiO 4 / 2 Polyorganosiloxane copolymers containing siloxane units represented by R 1 2 HSiO 1 / 2The siloxane unit represented by and SiO 4 / 2 Polyorganosiloxane copolymers containing siloxane units represented by R 1 HSiO 2 / 2 The siloxane unit represented by R 1 SiO 3 / 2 or HSiO 3 / 2 and mixtures of two or more of the foregoing. 1 is a hydrocarbon group other than an alkenyl group, and specifically may be an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, or a heptyl group; an aryl group such as a phenyl group, a tolyl group, a xylyl group, or a naphthyl group; an aralkyl group such as a benzyl group or a phenethyl group; or a halogen-substituted alkyl group such as a chloromethyl group, a 3-chloropropyl group, or a 3,3,3-trifluoropropyl group.

[0082] The content of the (2) polyorganosiloxane is not particularly limited as long as it is contained to an extent that suitable curing can be performed. For example, the (2) polyorganosiloxane may be contained in an amount such that the number of silicon-bonded hydrogen atoms is 0.5 to 10 per one alkenyl group contained in the (1) polyorganosiloxane. Within this range, curing can be sufficiently promoted and heat resistance can be ensured.

[0083] The addition-curable silicone composition may further include platinum or a platinum compound as a catalyst for curing. The specific type of platinum or platinum compound is not particularly limited. The proportion of the catalyst may be adjusted to a level that allows suitable curing.

[0084] The addition-curable silicone composition may also contain appropriate amounts of additives necessary for improving storage stability, ease of handling, and workability.

[0085] The silicone polymer layer may be a cured layer of a curable composition, such as the addition-curable silicone composition.

[0086] The curable composition is suitable for forming a light modulating device, comprising a polyorganosiloxane containing siloxane units of the following formula 1:

[0087] [Chemical formula 1] (HRSiO 2 / 2 )

[0088] In Formula 1, R is an alkyl group, an alkoxy group, or an aryl group.

[0089] The alkyl group in Chemical Formula 1 may be an alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms, or a methyl group or an ethyl group. The alkyl group may be linear, branched, or cyclic, and may be optionally substituted with one or more substituents. As a suitable example, the alkyl group may be an unsubstituted linear alkyl group.

[0090] The alkoxy group of Chemical Formula 1 may be an alkoxy group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms, or a methoxy group or an ethoxy group. The alkoxy group may be linear, branched, or cyclic, and may be optionally substituted with one or more substituents. As a suitable example, the alkoxy group may be an unsubstituted linear alkoxy group.

[0091] The aryl group of Chemical Formula 1 may be a monovalent residue derived from a compound or a derivative thereof, which includes a structure in which a benzene ring or two or more benzene rings are linked to each other through a suitable linker, or which are condensed or bonded while sharing one or more carbon atoms. The scope of the aryl group may include not only functional groups generally called aryl groups, but also so-called aralkyl groups or arylalkyl groups. The aryl group may be, for example, an aryl group having 6 to 25 carbon atoms, 6 to 21 carbon atoms, 6 to 18 carbon atoms, or 6 to 12 carbon atoms. Examples of the aryl group include a phenyl group, a dichlorophenyl group, a chlorophenyl group, a phenylethyl group, a phenylpropyl group, a benzyl group, a tolyl group, a xylyl group, and a naphthyl group.

[0092] As a suitable example, in Formula 1, R may be an alkyl group.

[0093] The ratio of the moles of the siloxane units of the formula 1 to the total siloxane units of the polyorganosiloxane containing the siloxane units of the formula 1 can be controlled. In one example, the ratio of the moles of the siloxane units of the formula 1 to the total siloxane units of the polyorganosiloxane is about 0.001 mol% or more, 0.005 mol% or more, 0.01 mol% or more, 0.05 mol% or more, 0.1 mol% or more, 0.5 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 15 mol% or more, 20 mol% or more, 25 mol% or more, or 30 mol% or more. or less than 100 mol%, 95 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 75 mol% or less, 70 mol% or less, 65 mol% or less, 60 mol% or less, 55 mol% or less, 50 mol% or less, 45 mol% or less, 40 mol% or less, 35 mol% or less, 30 mol% or less, 25 mol% or less, 20 mol% or less, 15 mol% or less, 10 mol% or less, 5 mol% or less, or 1 mol% or less. The proportion of the number of moles of the siloxane units of Chemical Formula 1 may be within the range between any one of the upper limits described above and any one of the lower limits described above.

[0094] The polyorganosiloxane may have a linear or branched structure while containing the siloxane unit of the above-mentioned chemical formula 1. As is known, polyorganosiloxanes containing only so-called M units (monofunctional siloxane units) and D units (polyfunctional siloxane units) as siloxane units have a linear structure, while polyorganosiloxanes having a branched structure contain siloxane units that are so-called T units (trifunctional siloxane units) and / or Q units (tetrafunctional siloxane units).

[0095] In one example, even when the polyorganosiloxane has a branched structure, the total ratio of the T units and Q units based on the mole number of the total siloxane units in the polyorganosiloxane is 10 mol% or less, 9 mol% or less, 8 mol% or less, 7 mol% or less, 6 mol% or less, 5 mol% or less, 4 mol% or less, 3 mol% or less, 2 mol% or less, 1 mol% or less, or 0.5 mol% or less, or more than 0 mol%. When the polyorganosiloxane has a linear structure, the total ratio of the T units and Q units is 0 mol%.

[0096] The chain end of the polyorganosiloxane may be a siloxane unit of the following chemical formula 2. That is, the polyorganosiloxane may be end-capped with a siloxane unit of the following chemical formula 2.

[0097] [Chemical formula 2] (R 1 3 SiO 1 / 2 )

[0098] In formula 2, R 1 is a hydrogen atom, an alkyl group, an alkoxy group, or an aryl group.

[0099] Specific examples of the alkyl group, alkoxy group, and aryl group in Chemical Formula 2 are the same as R in Chemical Formula 1. 1 is an alkyl group, an alkoxy group, or an aryl group, or may be an alkyl group.

[0100] The polyorganosiloxane may further include a siloxane unit of the following formula 3:

[0101] [Chemical formula 3] (R 2 2 SiO 2 / 2 )

[0102] In formula 3, R 2 is an alkyl group, an alkoxy group, or an aryl group.

[0103] Specific examples of the alkyl group, alkoxy group, and aryl group in Chemical Formula 3 are the same as R in Chemical Formula 1. 2 may be an alkyl group.

[0104] The molar mass of the polyorganosiloxane may be in the range of 200 g / mol to 2,000,000 g / mol. The molar mass is a value calculated from the number of moles of silicon atoms, oxygen atoms, carbon atoms, and hydrogen atoms contained in the polyorganosiloxane and their molar masses. In addition, the molar mass of the polyorganosiloxane is about 500 g / mol or more, 1,000 g / mol or more, 3,000 g / mol or more, 5,000 g / mol or more, 7,000 g / mol or more, 9,000 g / mol or more, 10,000 g / mol or more, 30,000 g / mol or more, 50,000 g / mol or more, or 70,000 g / mol or more, or about 1,500,000 g / mol or less, The molar mass may be about 1,000,000 g / mol or less, 500,000 g / mol or less, 100,000 g / mol or less, 90,000 g / mol or less, 70,000 g / mol or less, 50,000 g / mol or less, 30,000 g / mol or less, 10,000 g / mol or less, 9,000 g / mol or less, 7,000 g / mol or less, 5,000 g / mol or less, or 4,500 g / mol or less. The molar mass may be within the range between any one of the lower limits described above and any one of the upper limits described above.

[0105] In a specific example, the polyorganosiloxane may be a polyorganosiloxane represented by the following formula 4.

[0106] [Chemical formula 4] [ka]

[0107] In Chemical Formula 4, each R is independently an alkyl group, an alkoxy group, or an aryl group, and m and n are any numbers.

[0108] In formula 4, HRSiO 2 / 2 Siloxane unit and R 2 SiO 2 / 2 Although the siloxane units are illustrated in the form of a block copolymer, this is for the convenience of explanation, and the siloxane units may also be included in the form of a random copolymer.

[0109] In Chemical Formula 4, m may be about 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, 8 or more, 9 or more, or 10 or more, or about 1,000 or less, 900 or less, 800 or less, 700 or less, 600 or less, 500 or less, 400 or less, 300 or less, 200 or less, 100 or less, 90 or less, 80 or less, 70 or less, 60 or less, 50 or less, 40 or less, 30 or less, 20 or less, 15 or less, 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, or 5 or less. The m may be within the range of any one of the upper limits described above and any one of the lower limits described above.

[0110] In Chemical Formula 4, n may be about 0 or more, 20 or more, 40 or more, 60 or more, 80 or more, 100 or more, 200 or more, 300 or more, 400 or more, 500 or more, 600 or more, 700 or more, 800 or more, or 900 or more; or about 20,000 or less, 15,000 or less, 10,000 or less, 5,000 or less, 1,000 or less, 950 or less, 900 or less, 850 or less, 800 or less, 750 or less, 700 or less, 650 or less, 600 or less, 550 or less, 500 or less, 450 or less, 400 or less, 350 or less, 300 or less, 250 or less, 200 or less, 150 or less, 100 or less, 90 or less, 80 or less, 70 or less, 60 or less, 50 or less, or 40 or less. The n may be within the range between any one of the upper limits recited above and any one of the lower limits recited above.

[0111] As an example of the polyorganosiloxane of Chemical Formula 4, a polyorganosiloxane may be used in which the alkyl group accounts for 50 mol% or more, 55 mol% or more, 60 mol% or more, 65 mol% or more, 70 mol% or more, 75 mol% or more, 80 mol% or more, 85 mol% or more, 90 mol% or more, or 95 mol% or more of the total number of moles of R in Chemical Formula 4. There is no particular upper limit to the proportion of the alkyl group, but the alkyl group may be contained in an amount of 100 mol% or less or less than 100 mol% of the total number of moles of R.

[0112] The polyorganosiloxane containing the siloxane unit of the above Chemical Formula 1 or the polyorganosiloxane of the above Chemical Formula 4 can form the desired silicone polymer layer by appropriately crosslinking the above alkenyl group-containing polyorganosiloxane.

[0113] The content of the polyorganosiloxane containing the siloxane unit of the formula 1 or the polyorganosiloxane of the formula 4 in the silicone polymer layer may be adjusted. For example, the content may be 2% by weight or more, 2.5% by weight or more, 3% by weight or more, 3.5% by weight or more, 4% by weight or more, 4.5% by weight or more, 5% by weight or more, 5.5% by weight or more, 6% by weight or more, 6.5% by weight or more, 7% by weight or more, 7.5% by weight or more, 8% by weight or more, 8.5% by weight or more, 9% by weight or more, 9.5% by weight or more, 10% by weight or more, 10.5% by weight or more, 11% by weight or more, 11.5% by weight or more, 12% by weight or more, 12.5% ​​by weight or more, or 13% by weight or more. In other examples, the content may be 50% by weight or less, 48% by weight or less, 46% by weight or less, 44% by weight or less, 42% by weight or less, 40% by weight or less, 38% by weight or less, 36% by weight or less, 34% by weight or less, 32% by weight or less, 30% by weight or less, 28% by weight or less, 26% by weight or less, 24% by weight or less, 22% by weight or less, 20% by weight or less, 18% by weight or less, 16% by weight or less, 14% by weight or less, 12% by weight or less, 10% by weight or less, 9% by weight or less, 8% by weight or less, 7% by weight or less, 6% by weight or less, 5% by weight or less, or 4% by weight or less. The ratio may be controlled within the range between any one of the upper limits described above and any one of the lower limits described above.

[0114] Within this range of content, the desired alignment state of the liquid crystal compound can be achieved and a light modulation device having excellent durability can be formed.

[0115] In the silicone polymer layer containing the polyorganosiloxane, δ in the following formula 2 may be within a predetermined range.

[0116] [Formula 2]

number

[0117] In Equation 2, M 1 is the siloxane unit of the chemical formula 1 contained in the polyorganosiloxane (in the case of the polyorganosiloxane of the chemical formula 4, HRSiO 2 / 2m is the molar mass (g / mol) of the siloxane unit of the chemical formula 1 contained in the polyorganosiloxane (m in the case of chemical formula 4), β is the content (wt%) of the polyorganosiloxane containing the siloxane unit of the chemical formula 1 in the silicone polymer layer, M 2 is the molar mass (g / mol) of the polyorganosiloxane.

[0118] In the present application, δ in formula 2 is more than 10, 10.5 or more, 11 or more, 12 or more, 13 or more, 14 or more, 15 or more, 16 or more, 17 or more, 18 or more, 19 or more, 20 or more, 21 or more, 22 or more, 23 or more, 24 or more, 25 or more, 26 or more, 27 or more, 28 or more, 29 or more, 30 or more, 31 or more, 32 or more, 33 or more, 34 or more, 35 or more, 36 or more, 37 or more, 38 or more, 39 or about 40 or more, 41 or more, 42 or more, 43 or more, 44 or more, 45 or more, 46 or more, 47 or more, 48 or more, 49 or more, or 50 or more, or about 100 or less, 95 or less, 90 or less, 85 or less, 80 or less, 75 or less, 70 or less, 65 or less, 60 or less, 55 or less, 50 or less, 45 or less, 40 or less, 35 or less, 30 or less, 25 or less, 20 or less, or 15 or less. The δ can be controlled within the range between any one of the upper limits described above and any one of the lower limits described above.

[0119] When two or more polyorganosiloxanes containing the siloxane unit of Formula 1 are present in the silicone polymer layer, the δ is calculated for each polyorganosiloxane, and the sum of the calculated δ can be designated as the δ value of the silicone polymer layer.

[0120] Within this range of content, the desired alignment state of the liquid crystal compound can be achieved and a light modulation device having excellent durability can be formed.

[0121] In Equation 2, M 1For example, M may be about 50 g / mol or more, 55 g / mol or more, or 60 g / mol or more, or about 200 g / mol or less, 180 g / mol or less, 160 g / mol or less, 140 g / mol or less, 120 g / mol or less, 100 g / mol or less, 80 g / mol or less, 75 g / mol or less, 70 g / mol or less, or 65 g / mol or less. 1 can be controlled.

[0122] In formula 2, m may be about 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, 8 or more, 9 or more, or 10 or more, or about 1,000 or less, 900 or less, 800 or less, 700 or less, 600 or less, 500 or less, 400 or less, 300 or less, 200 or less, 100 or less, 90 or less, 80 or less, 70 or less, 60 or less, 50 or less, 40 or less, 30 or less, 20 or less, 15 or less, 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, or 5 or less. The m may be within the range of any one of the upper limits described above and any one of the lower limits described above.

[0123] M in Equation 2 2is, for example, about 200 g / mol or more, 500 g / mol or more, 1,000 g / mol or more, 3,000 g / mol or more, 5,000 g / mol or more, 7,000 g / mol or more, 9,000 g / mol or more, 10,000 g / mol or more, 30,000 g / mol or more, 40,000 g / mol or more, or 45,000 g / mol or more; or about 2,000,000 g / mol or less, 1,500,000 g / mol or less, 1,000,000 g / mol or less, 500,000 g / mol or less, 1 It may be about 00,000 g / mol or less, 90,000 g / mol or less, 70,000 g / mol or less, 50,000 g / mol or less, 30,000 g / mol or less, 10,000 g / mol or less, 9,000 g / mol or less, 7,000 g / mol or less, 5,000 g / mol or less, 4,500 g / mol or less, 4,000 g / mol or less, 3,500 g / mol or less, 3,000 g / mol or less, 2,500 g / mol or less, 2,000 g / mol or less, or 1,500 g / mol or less. 2 may be within the range between any one of the lower limits listed above and any one of the upper limits listed above.

[0124] Furthermore, in formula 2, β may be about 2 weight% or more, 2.5 weight% or more, 3 weight% or more, 3.5 weight% or more, 4 weight% or more, 4.5 weight% or more, 5 weight% or more, 5.5 weight% or more, 6 weight% or more, 6.5 weight% or more, 7 weight% or more, 7.5 weight% or more, 8 weight% or more, 8.5 weight% or more, 9 weight% or more, 9.5 weight% or more, 10 weight% or more, 10.5 weight% or more, 11 weight% or more, 11.5 weight% or more, 12 weight% or more, 12.5 weight% or more, or 13 weight% or more. In other examples, the β may be 50% by weight or less, 48% by weight or less, 46% by weight or less, 44% by weight or less, 42% by weight or less, 40% by weight or less, 38% by weight or less, 36% by weight or less, 34% by weight or less, 32% by weight or less, 30% by weight or less, 28% by weight or less, 26% by weight or less, 24% by weight or less, 22% by weight or less, 20% by weight or less, 18% by weight or less, 16% by weight or less, 14% by weight or less, 12% by weight or less, 10% by weight or less, 9% by weight or less, 8% by weight or less, 7% by weight or less, 6% by weight or less, 5% by weight or less, or 4% by weight or less. The ratio may be controlled within the range between any one of the upper limits described above and any one of the lower limits described above.

[0125] The curable composition forming the silicone polymer layer may be any known addition curing composition without any particular limitation, so long as it contains the polyorganosiloxane of Formula 1 in a manner that satisfies the above conditions. Any silicone adhesive or pressure-sensitive adhesive known in the industry as OCA or OCR may be used in the present application. The silicone polymer layer may be formed by blending the polyorganosiloxane of Formula 1 into the silicone adhesive or pressure-sensitive adhesive in a manner that satisfies the above conditions.

[0126] For example, the curable composition may contain an alkenyl group-containing polyorganosiloxane in addition to the polyorganosiloxane of the chemical formula 1. As the alkenyl group-containing polyorganosiloxane, the above-mentioned (1) polyorganosiloxane containing two or more alkenyl groups in the molecule may be used.

[0127] In addition, when the polyorganosiloxane of Chemical Formula 1 is present, the polyorganosiloxane may further include the above-mentioned (2) polyorganosiloxane containing two or more silicon-bonded hydrogen atoms in the molecule as a polyorganosiloxane having a structure different from that of the polyorganosiloxane of Chemical Formula 1.

[0128] In such a case, the content of the alkenyl group-containing polyorganosiloxane and / or polyorganosiloxane containing two or more silicon-bonded hydrogen atoms in the molecule in the silicone polymer layer or the curable composition may be, for example, 60% by weight or more, 65% by weight or more, 70% by weight or more, 75% by weight or more, 80% by weight or more, 85% by weight or more, 90% by weight or more, or 95% by weight or more. In other examples, the content may be less than 100% by weight, 95% by weight or less, 90% by weight or less, or 87% by weight or less. The ratio may be controlled within the range of any one of the upper limits mentioned above and any one of the lower limits mentioned above.

[0129] The curable composition or silicone polymer layer may contain any necessary ingredients in addition to those described above, such as an addition curing catalyst.

[0130] The type of the curable composition is not particularly limited and may be appropriately selected depending on the intended use. For example, a solid-phase, semi-solid-phase, or liquid curable composition may be used. A solid-phase or semi-solid-phase curable composition may be cured before the objects to be bonded are bonded. A liquid curable composition is called an optically clear resin (OCR) and may be cured after the objects to be bonded are bonded.

[0131] The thickness of the silicone polymer layer formed from the curable composition as described above can be adjusted depending on the purpose, and is not particularly limited, and can usually be formed to a thickness within the range of 1 μm to 100 μm.

[0132] When the silicone polymer layer is formed on the first substrate, the liquid crystal alignment film may not be formed on the first substrate, and therefore, in this case, the liquid crystal alignment film may not be present between the first substrate and the liquid crystal layer.

[0133] In the light modulation device, a liquid crystal alignment layer may be present between the liquid crystal layer and the second substrate, and the liquid crystal alignment layer may be formed on a surface of the second substrate, for example, a surface facing the liquid crystal layer.

[0134] There is no particular limit to the type of liquid crystal alignment film that can be formed in the light modulation device. As the alignment film, a known vertical or horizontal alignment film or other alignment film can be applied in consideration of the desired initial alignment. The alignment film can be a contact type alignment film such as a rubbing alignment film or a non-contact type alignment film such as a photo-alignment film. As one example, a vertical alignment film can be used as the alignment film. For example, a combination of a vertical alignment film and the above-mentioned silicone polymer layer can induce an alignment state of liquid crystal compounds suitable for various applications.

[0135] The initial alignment film of the liquid crystal compound formed by the liquid crystal alignment film and / or the silicone polymer layer and the liquid crystal alignment film in the liquid crystal layer may be vertical alignment, horizontal alignment, tilt alignment or splay alignment. In addition, in the vertical alignment, horizontal alignment, tilt alignment or splay alignment state, the liquid crystal compound may or may not be twisted to be in the twist alignment or cholesteric alignment state. The initial alignment means the alignment of the liquid crystal compound in the initial state, i.e., in the state where no external energy is applied to the liquid crystal layer.

[0136] The meanings of the horizontal alignment, tilt alignment, vertical alignment, and splay alignment are as known in the art. The liquid crystal compound of the transmittance variable layer maintains the horizontal alignment, tilt alignment, vertical alignment, or splay alignment state in the initial state, and can be changed to a different alignment state by an external signal.

[0137] In one example, the initial alignment of the liquid crystal compound in the transmittance variable layer is a vertical alignment or an alignment state similar to the vertical alignment, and the twisted alignment can be realized when an external signal is applied. This alignment state can be obtained by applying a vertical alignment film as the liquid crystal alignment film. This alignment is useful for a device that realizes a so-called R-TN (Reversed Twisted Nematic) alignment.

[0138] The in-plane retardation (based on a wavelength of 550 nm) of the transmittance variable layer in the vertical alignment or an alignment state similar to the vertical alignment may be, for example, about 30 nm or less, 25 nm or less, 20 nm or less, 15 nm or less, 10 nm or less, or 5 nm or less, or may be 0 nm or more or more than 0 nm.

[0139] The in-plane retardation is calculated by the formula A, where n x , n y and d are the slow axis direction refractive index, fast axis direction refractive index and thickness of the light modulation layer, respectively.

[0140] The light modulation device may further include a spacer that maintains a distance between the first and second substrates. As the spacer, a ball spacer, a column spacer, or a partition-type spacer, or a combination of two or more of the above, may be used as a commonly used spacer. As a suitable example, the partition-type spacer may be used, and in particular, a partition-type spacer in which the partition forms at least one closed figure may be used. Examples of the closed figure formed by the partition-type spacer include a hexagon (e.g., a regular hexagon, etc.) and a quadrangle (e.g., a square or a rectangular parallelepiped). The partition-type spacer in which the closed figure is a hexagon, in particular, a regular hexagon, is also called a honeycomb-type spacer. As is well known, such a honeycomb-type or quadrangle-type partition spacer refers to a case in which the figure formed by the partition-type spacer is a honeycomb-type or quadrangle when the shape of the partition-type spacer formed on the substrate is observed from the normal direction of the substrate. The honeycomb pattern is generally formed of a combination of regular hexagons, and in the case of a quadrangle, it may be a square, a rectangular prism, or a combination of a square and a rectangular prism, etc. Taking into consideration the adhesive force between the first and second substrates, a partition-type spacer may be used as the spacer, but is not limited thereto.

[0141] The pitch of the spacer may be appropriately selected in consideration of the desired adhesive force and the maintenance efficiency of the cell cap. For example, when a partition-type spacer is applied, the pitch of the partition-type spacer may be within a range of 50 μm to 2,000 μm. A method for determining the pitch of a partition-type spacer is publicly known. For example, if the partition-type spacer is a honeycomb type, the pitch is determined from the distance between the opposing sides of a hexagon forming the honeycomb, and if the spacer is a rectangle, the pitch is determined from the length of the side of the rectangle. If the distance between the opposing sides of the hexagon forming the honeycomb or the length of the side of the rectangle are not constant, the average value thereof can be defined as the pitch.

[0142] When the partition-type spacer forms a closed shape, the area of ​​the closed shape (i.e., the area of ​​a hexagon or a rectangle, for example) is, for example, about 1 mm 2~200mm 2 In the case where a plurality of closed figures are formed by the bulkhead-type spacers and the areas of the closed figures are different from one another, the above-mentioned area is an arithmetic average value.

[0143] The line width of the partition-type spacer, for example, the width of each wall of the hexagon or rectangle forming the honeycomb, may be, for example, within a range of about 5 μm to 50 μm. In other examples, the line width may be about 10 μm or more, or 15 μm or more, or about 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, or 20 μm or less.

[0144] Within the above range, the cell cap can be properly maintained and excellent adhesion between the substrates can be maintained. For example, when the silicone polymer layer is formed on the first substrate, the combination with the partition-type spacer can provide excellent adhesion between the substrates.

[0145] An electrode layer may be formed on each substrate of the light modulation device as a component for applying an external signal to the transmittance variable layer. For example, an electrode layer may be present between the first surface and the functional layer (liquid crystal alignment film, adhesive or adhesive layer (between 100 and 1001 in FIG. 2)) of the first substrate and / or between the first surface and the liquid crystal alignment film (between 200 and 2001 in FIG. 2) of the second substrate (between the spacer and the alignment film if a spacer is present). In the case of the second substrate, it is common to first form an electrode layer on the first surface, and then sequentially form a spacer and an alignment film thereon. Therefore, if a spacer is present, the electrode layer may be located between the first surface of the second substrate and the spacer and the alignment film.

[0146] The electrode layer may be a known transparent electrode layer, for example, a so-called conductive polymer layer, a conductive metal layer, a conductive nanowire layer, or a metal oxide layer such as ITO (Indium Tin Oxide). In addition, various materials and methods for forming a transparent electrode layer are known, and may be used without limitation.

[0147] The light modulation device may basically include the light modulation device and may include additional components as necessary. That is, depending on the driving mode, the light modulation device alone can realize the above-mentioned transmission, blocking, high reflection, and / or low reflection modes and switch between them, but it may also include additional components to facilitate the realization or switching of such modes.

[0148] For example, the element may further include a polarizing layer (passive polarizing layer) disposed on one or both sides of the light modulation device. Fig. 3 shows an example of the structure in which a polarizing layer 400 is disposed on only one side of the light modulation device in the structure of Fig. 2, and Fig. 4 shows an example of the structure in which a polarizing layer 400 is disposed on both sides of the light modulation device in the structure of Fig. 2. In addition, when the partition-type spacer is used as the spacer and has a quadrilateral shape (square or rectangular parallelepiped), it is appropriate that the sides of the quadrilateral and the absorption axis of the polarizing layer are disposed substantially perpendicular or horizontal to each other.

[0149] The term "polarizing layer" may refer to an element that converts natural light or non-polarized light into polarized light. In one example, the polarizing layer may be a linear polarizing layer. A linear polarizing layer refers to a case where selectively transmitted light is linearly polarized light that vibrates in one direction, and selectively absorbed or reflected light is linearly polarized light that vibrates in a direction perpendicular to the vibration direction of the linearly polarized light. That is, the linear polarizing layer may have transmission and absorption axes or reflection axes that are perpendicular to each other in the plane direction.

[0150] The polarizing layer may be an absorptive polarizing layer or a reflective polarizing layer. The absorptive polarizing layer may be, for example, a polarizing layer obtained by dyeing a polymer stretched film such as a PVA (poly(vinyl alcohol)) stretched film with iodine, or a guest-host polarizing layer in which a liquid crystal polymerized in an oriented state serves as a host and a dichroic dye aligned by the orientation of the liquid crystal serves as a guest, but is not limited thereto.

[0151] The reflective polarizing layer may be, for example, a reflective polarizing layer known as a dual brightness enhancement film (DBEF) or a reflective polarizing layer formed by coating a liquid crystal compound such as lyotropic liquid crystal (LLC), but is not limited thereto.

[0152] The polarizing layers may be disposed on both sides of the light modulation device as shown in Fig. 4. In this case, the angle between the transmission axes of the polarizing layers disposed on both sides may be within a range of 85 degrees to 95 degrees or may be approximately perpendicular.

[0153] In one example, the optical element may be configured without including a polarizing layer. For example, the optical element may be configured without applying a polarizing layer after blending a dichroic dye as an additional component into the liquid crystal layer.

[0154] The light modulation device may include other necessary components in addition to the above components.

[0155] For example, the light modulation device may further include an optically anisotropic film that satisfies the refractive index relationship of the following Equation 4. Such a film may optically compensate the substrate or the light modulation layer to further improve the performance of the device.

[0156] [Formula 4] n z <n y

[0157] In formula 4, n y is the refractive index of the optically anisotropic film in the fast axis direction at a wavelength of 550 nm, and n z is the refractive index at a wavelength of 550 nm in the thickness direction of the optically anisotropic film.

[0158] An optically anisotropic film that satisfies the relationship of the above mathematical formula 4 is a film that exhibits the properties of a so-called negative C plate.

[0159] The thickness direction retardation of such an optically anisotropic film may be, for example, within a range of less than 0 nm to -600 nm or more based on a wavelength of 550 nm. The optically anisotropic film may be present in one or more layers in an optical element, and the thickness direction retardation is the thickness direction retardation of the film in the case where one optically anisotropic film is present, and is the total thickness direction retardation of the mode films in the case where two or more layers are present.

[0160] The thickness direction retardation is a physical quantity determined by the following formula 5.

[0161] [Formula 5] R th =d×(n z -n y )

[0162] In Equation 5, R th is the thickness direction retardation, and n z is the thickness refractive index of the film, and n y is the fast axis refractive index of the film, and d is the thickness of the film, where the meanings of thickness direction and fast axis are well known in the art.

[0163] The optically anisotropic film may be a known retardation film that satisfies the above formula 4. In the art, various types of films are known, such as stretched polymer films and liquid crystal films.

[0164] The optically anisotropic film may be present on the first and / or second substrate, for example, it may be formed on the first surface of the first and / or second substrate. In this case, the optically anisotropic film may be present between the first and / or second substrate and the transmittance variable layer, and when a liquid crystal alignment film or the silicone polymer layer is formed on the first surface, it may be formed between the first and / or second substrate and the liquid crystal alignment film, etc., and when an electrode layer is formed on the first surface, it may be formed between the first and / or second substrate and the electrode layer.

[0165] The light modulation device may include other components as necessary in addition to the above components. For example, in addition to the silicone polymer layer formed on the first surface of the first substrate, any other components necessary for driving or using the light modulation device may be added, such as a pressure-sensitive adhesive layer or adhesive layer for attaching other components, a hard coating film, an anti-reflection film, and / or a NIR (Near-Infrared) cut layer.

[0166] The method for manufacturing the optical modulation device is not particularly limited, and the device can be manufactured by a known method other than the application of the above-mentioned elements as each component.

[0167] Such optical elements can be used in a variety of applications, including, for example, eyewear such as sunglasses and eyewear for AR (Argumented Reality) or VR (Virtual Reality), the exterior walls of buildings, and sunroofs for vehicles. Effect of the Invention

[0168] The present application can provide a light modulation device and use thereof. The present application can provide a light modulation device and use thereof that can stably maintain the alignment of a liquid crystal compound while securing adhesion between opposing substrates by applying a pressure-sensitive adhesive layer or an adhesive layer, and can particularly stably maintain or realize a desired alignment state of a liquid crystal compound for a long period of time even at high temperatures. [Brief description of the drawings]

[0169] [Figure 1] FIG. 2 is a diagram showing a process for measuring transmittances T1 and T2. [Diagram 2] 1 is a schematic diagram of an exemplary light modulating device of the present application. [Diagram 3] 1 is a schematic diagram of an exemplary light modulating device of the present application. [Figure 4] 1 is a schematic diagram of an exemplary light modulating device of the present application. EXAMPLES

[0170] Hereinafter, the optical modulator of the present application will be described in detail with reference to examples. However, the scope of the present application is not limited to the following examples.

[0171] 1. Evaluation of phase difference In-plane retardation value of the film (R in ) was measured for light with a wavelength of 550 nm using Agilent UV / VIS spectroscope 8453. Two polarizers were installed in the UV / VIS spectroscope so that the transmission axes were perpendicular to each other, and the film was installed between the two polarizers so that the slow axis of the film was at 45 degrees to the transmission axes of the two polarizers, and then the transmittance was measured according to wavelength. The phase retardation order of each peak in the transmittance graph according to wavelength is calculated. Specifically, in the transmittance graph according to wavelength, the waveform satisfies the following formula A, and the condition for the maximum peak (Tmax) in a sine waveform satisfies the following formula B. When λmax is found in formula A, T in formula A and T in formula B are the same, so the formula is expanded. The formulas are also expanded for n+1, n+2, and n+3, the n and n+1 formulas are rearranged, R is eliminated, and n is rearranged with the λn and λn+1 formulas, leading to the following formula C. Since n and λ can be known based on the fact that T in formula A and T in formula B are the same, R is found for each λn, λn+1, λn+2, and λn+3. A linear trend line of R values ​​by wavelength is found for the four points, and the R value for the formula 550 nm is calculated. The function of the linear trend line is Y=ax+b, where a and b are constants. The Y value when 550 nm is substituted for x in the above function is the R value for light with a wavelength of 550 nm. in value.

[0172] [Formula A] T=sin 2 [(2πR / λ)]

[0173] [Formula B] T=sin 2 [((2n+1)π / 2)]

[0174] [Formula C] n=(λn-3λn+1) / (2λn+1+1-2λn)

[0175] In the above, R means an in-plane retardation (Rin), λ means a wavelength, and n means an order of the peak of a sine wave.

[0176] 2. Transmittance Measurement The transmittance of the light modulation device was measured in the following manner. An apparatus for measuring the transmittance was manufactured in the following manner. The light modulation device manufactured in the examples or comparative examples was placed between two PVA (poly(vinyl alcohol)) polarizing layers. The polarizing layers were arranged so that their absorption axes were perpendicular to each other, and the light modulation device was arranged so that the slow axis of the substrate was perpendicular to the absorption axis of one of the two polarizing layers and parallel to the absorption axis of the other polarizing layer.

[0177] In the above state, the transmittance (T in Equation 1) for light with a wavelength of 370 nm to 780 nm at room temperature (about 25° C.) 1 The transmittance T 1 The transmittance is measured from 370 nm to 780 nm at 2 nm wavelength intervals, and the average value of the measured transmittance is calculated to obtain the T 1 The transmittance was measured by irradiating one of the two polarizing layers with light of the wavelength in the normal direction to the polarizing layer, and then measuring the transmittance on the opposite polarizing layer side along the normal direction to the surface of the polarizing layer.

[0178] Next, a temperature control device (LTS-350, Kinkam) was installed in the apparatus, and the temperature control device was positioned between the light modulation device and the polarizer (the polarizer closest to the transmittance measurement unit) in a structure in which the light source, polarizer, light modulation device, polarizer, and transmittance measurement unit of the transmittance measurement unit were sequentially arranged.

[0179] The optical modulation device was then maintained at 90° C. for 5 minutes using the temperature control device, and the transmittance (T in Equation 1) was measured in the same manner as above while the temperature was maintained at 90° C.2 ) was evaluated.

[0180] The transmittance T 1 and T 2 During the evaluation process and during the process of maintaining the light modulation device at 90° C. for 5 minutes, no power was applied to the light modulation device, so the liquid crystal layer was in a vertical alignment state.

[0181] The transmittance was evaluated using a Blue Wave device (manufacturer: Stellar Net).

[0182] 3. Measurement of changes over 30 days The change over 30 days was measured by the following method: As described in the Examples or Comparative Examples, a silicone polymer layer was formed to a thickness of about 8 μm on a PET (poly(ethylene terephthalate)) film (SKC, highly stretched PET, Rin=about 10,000 nm) having a thickness of about 145 μm and an ITO (indium tin oxide) electrode layer formed on one side.

[0183] Immediately after forming the silicone polymer layer, the substrate was cut to manufacture an optical modulation device in the same manner as in Example 1, and the transmittance T 1 The transmittance (T 1 ) was measured.

[0184] The remaining substrates (substrates on which the silicone polymer layer was formed) were maintained at room temperature / pressure / humidity for 30 days, and then the same optical modulation devices were manufactured using the corresponding substrates. The transmittance (T a ) was measured.

[0185] Next, the transmittance T i and T a Substituting △T 30 The absolute value was evaluated as "OK" when it was 300% or less, and as "NG" when it was over 300%.

[0186] <Formula A>

number

[0187] <Example 1> A PET (poly(ethylene terephthalate)) film (SKC, highly stretched PET) with a thickness of about 145 μm and an ITO (indium tin oxide) electrode layer formed on one side was used as the first substrate. The in-plane retardation of the PET film was about 10,000 nm based on a wavelength of 550 nm.

[0188] A silicone polymer layer was formed on the ITO electrode layer of the PET film using a silicone OCA (Optically Clear Adhesive) composition (Si-Feliz, HA-578A product, solid content 60% by weight) that forms an adhesive layer.

[0189] A platinum catalyst (Si-Feliz, HA-04C product) was added as a catalyst to the silicone OCA (Optically Clear Adhesive) composition (Si-Feliz, HA-578A product) at a ratio of about 1.67 wt %, and a polyorganosiloxane of the following formula A (Gelest) was added to prepare a coating liquid. The polyorganosiloxane of the formula A was added so that the polyorganosiloxane was present in the formed silicone polymer layer at a concentration of about 13.3 wt %.

[0190] [Chemical formula A] [ka]

[0191] In chemical formula A, R is a methyl group, m is a number about 7, and n is a number about 600.

[0192] Next, the coating liquid was bar-coated onto the ITO layer of the first substrate and cured by maintaining it at a temperature of about 140° C. for 4 minutes to form a silicone polymer layer with a thickness of about 8 μm.

[0193] The coating was formed so that the silicone polymer layer covered the entire area of ​​the ITO layer formed on the entire surface of the PET film.

[0194] The silicone polymer layer to which the polyorganosiloxane of formula A is added is represented by formula 2, 1 is the siloxane unit HMeSiO 2 / 2 The unit molar mass (g / mol) is about 60.13 g / mol, m is about 8, and β is 13.3% by weight.

[0195] The molar mass of the polyorganosiloxane of formula A is about 45,075 g / mol.

[0196] Therefore, in the following formula 2, M 1 is 60.13, m is 7, β is 13.3, M 2 A value of 45,075 is substituted for , and δ is calculated to be approximately 12.4.

[0197] [Formula 2]

number

[0198] A PET (poly(ethylene terephthalate)) film (Toyobo, SRF product) with a thickness of about 80 μm and an ITO (indium tin oxide) layer formed on the surface was used as the second substrate. The in-plane retardation of the second substrate was about 9,000 nm at a wavelength of 550 nm.

[0199] As a partition-type spacer forming a closed rectangular shape on the ITO layer of the PET film, a partition-type spacer having a pitch of about 350 μm, a line width of about 10 μm, and a height of about 6 μm was formed with an area ratio (the proportion of the area occupied by the spacers to the total substrate area) of about 9%.

[0200] A vertical alignment film (5661LB3, Nissan) was formed on the spacer. The alignment film was formed by diluting the alignment film material (5661LB3, Nissan) in a solvent to a solid content of about 2.2% by weight, and maintaining the material at 100°C for about 10 minutes after #2 bar coating. The vertical alignment film was formed by rubbing in one direction. The rubbing direction was perpendicular to the slow axis direction of the second substrate.

[0201] Next, a liquid crystal composition was coated on the vertical alignment film of the second substrate, and the surface of the second substrate on which the vertical alignment film was formed and the silicone polymer layer of the first substrate were laminated so as to face each other, thereby manufacturing an optical modulation device. During the lamination, the slow axes of the first and second substrates were made parallel to each other.

[0202] The liquid crystal composition used was a composition containing a nematic liquid crystal compound (Merck, MAT-19-1205) and a chiral dopant (Merck, S811). The content of the chiral dopant was adjusted so that the pitch (chiral pitch) (p) of the twisted alignment was about 20 μm.

[0203] <Example 2> An optical modulation device was manufactured in the same manner as in Example 1, except that polyorganosiloxane of chemical formula B was used instead of polyorganosiloxane of chemical formula A in the process of forming the silicone polymer layer.

[0204] When preparing the coating solution, the polyorganosiloxane of formula B was added so that the polyorganosiloxane was present in the formed silicone polymer layer at a concentration of about 5% by weight.

[0205] [Chemical formula B] [ka]

[0206] In formula B, R is a methyl group, m is a number about 1, and n is a number about 17.

[0207] The silicone polymer layer to which the polyorganosiloxane of formula B has been added is represented by formula 2, 1 is the siloxane unit HMeSiO 2 / 2 The unit molar mass (g / mol) is approximately 60.13 g / mol, m is 1, and β is 5% by weight.

[0208] The molar mass of the polyorganosiloxane of formula B is about 1,483 g / mol.

[0209] Therefore, the following formula 2, M 1 is 60.13, m is 1, β is 5, M 2 A value of 1,483 is substituted for , and δ is calculated to be approximately 20.3.

[0210] [Formula 2]

number

[0211] <Example 3> An optical modulation device was manufactured in the same manner as in Example 1, except that polyorganosiloxane of chemical formula C was used instead of polyorganosiloxane of chemical formula A in the process of forming the silicone polymer layer.

[0212] When preparing the coating solution, the polyorganosiloxane of formula C was added so that the polyorganosiloxane was present in the formed silicone polymer layer at a concentration of about 3.30% by weight.

[0213] [Chemical formula C] [ka]

[0214] In chemical formula C, R is a methyl group, m is a number about 5, and n is a number about 19.

[0215] The silicone polymer layer to which the polyorganosiloxane of formula C is added is represented by M of formula 2. 1 is the siloxane unit HMeSiO 2 / 2 The unit molar mass (g / mol) is about 60.13 g / mol, m is about 5, and β is 3.30% by weight.

[0216] The molar mass of the polyorganosiloxane of formula C is about 1,872 g / mol.

[0217] Therefore, the following formula 2, M 1 is 60.13, m is 5, β is 3.3, M 2 A value of 1,872 is substituted for , and δ is calculated to be approximately 53.

[0218] [Formula 2]

number

[0219] <Example 4> An optical modulator device was manufactured in the same manner as in Example 1, except that in the process of forming the silicone polymer layer, the polyorganosiloxane of formula B in Example 2 and the polyorganosiloxane of formula C in Example 3 were used together instead of the polyorganosiloxane of formula A.

[0220] When preparing the coating solution, the polyorganosiloxane of formula B was added so that the polyorganosiloxane was present in the formed silicone polymer layer at a concentration of about 2.5% by weight.

[0221] [Chemical formula B] [ka]

[0222] In formula B, R is a methyl group, m is a number about 1, and n is a number about 17.

[0223] The silicone polymer layer to which the polyorganosiloxane of formula B has been added is represented by formula 2, 1 is the siloxane unit HMeSiO 2 / 2 The unit molar mass (g / mol) is approximately 60.13 g / mol, m is 1, and β is 2.5% by weight.

[0224] The molar mass of the polyorganosiloxane of formula B is about 1,483 g / mol.

[0225] Therefore, the following formula 2, M 1 is 60.13, m is 1, β is 2.5, M 2 A value of 1,483 is substituted for , and δ is calculated to be approximately 10.1.

[0226] [Formula 2]

number

[0227] In addition, when preparing the coating solution, the polyorganosiloxane of formula C was added so that the polyorganosiloxane was present in the formed silicone polymer layer at a concentration of about 0.8 wt %.

[0228] [Chemical formula C] [ka]

[0229] In chemical formula C, R is a methyl group, m is a number about 5, and n is a number about 19.

[0230] The silicone polymer layer to which the polyorganosiloxane of formula C is added is represented by M of formula 2. 1 is the siloxane unit HMeSiO 2 / 2 The unit molar mass (g / mol) is about 60.13 g / mol, m is about 5, and β is 0.8% by weight.

[0231] The molar mass of the polyorganosiloxane of formula C is about 1,872 g / mol.

[0232] Therefore, in the following formula 2, M 1 is 60.13, m is 5, β is 0.8, M 2 A value of 1,872 is substituted for , and δ is calculated to be approximately 12.8.

[0233] [Formula 2]

number

[0234] Therefore, in the case of Example 4, the final δ is calculated to be about 22.9 (=10.1+12.8).

[0235] <Comparative Example 1> An optical modulation device was manufactured in the same manner as in Example 1, except that a coating liquid was used that was prepared by adding a platinum catalyst (Si-Feliz, HA-04C product) to a silicone OCA (Optically Clear Adhesive) composition (Si-Feliz, HA-578A product, solid content approximately 60% by weight) in a proportion of approximately 1.67% by weight.

[0236] <Comparative Example 2> An optical modulation device was manufactured in the same manner as in Example 1, except that when preparing the coating solution, the polyorganosiloxane of formula A was added so that the polyorganosiloxane was present in the formed silicone polymer layer at a concentration of about 6.7 wt %.

[0237] In such a case, in the following formula 2, M 1 is 60.13, m is 7, β is 6.7, M 2 A value of 45,075 is substituted for , and δ is calculated to be approximately 6.3.

[0238] [Formula 2]

number

[0239] <Comparative Example 3> An optical modulation device was manufactured in the same manner as in Example 2, except that when preparing the coating solution, the polyorganosiloxane of formula B was added so that the polyorganosiloxane was present in the formed silicone polymer layer at a concentration of about 2.5 wt %.

[0240] Therefore, in the following formula 2, M 1 is 60.13, m is 1, β is 2.5, M 2 A value of 1,483 is substituted for , and δ is calculated to be approximately 10.1.

[0241] [Formula 2]

number

[0242] <Comparative Example 4> An optical modulation device was manufactured in the same manner as in Example 3, except that when preparing the coating solution, the polyorganosiloxane of formula C was added so that the polyorganosiloxane was present in the formed silicone polymer layer at a concentration of about 1.7 wt %.

[0243] Therefore, in the following formula 2, M 1 is 60.13, m is 5, β is 1.7, M 2 A value of 1,872 is substituted for , and δ is calculated to be approximately 27.3.

[0244] [Formula 2]

number

[0245] The evaluation results for the optical modulation devices of the above-mentioned Examples and Comparative Examples are summarized in Table 1 below.

[0246] In Table 1 below, T on is the transmittance T in the section explaining the method for measuring the transmittance. 1 The transmittance was measured in the same manner as in measuring the transmittance of the light modulating device, except that the transmittance was measured while applying a voltage under square wave form conditions (48 Vrms, 60 Hz) to the light modulating device.

[0247] [Table 1]

[0248] As shown in Table 1, all of the optical modulation devices of the present application exhibited excellent reliability when maintained under high temperature conditions for long periods of time.

[0249] However, Comparative Example 1, which does not contain the polyorganosiloxane of Formula 1, Comparative Examples 2 and 3, which contain the polyorganosiloxane but the δ value does not exceed 10, and Comparative Example 4, which has a low content of the polyorganosiloxane, all did not show suitable results.

Claims

1. first and second substrates disposed opposite each other; a liquid crystal layer present between the first and second substrates; a silicone polymer layer present between the first substrate and a liquid crystal layer; The silicone polymer layer is a cured layer of a curable composition including a polyorganosiloxane having a siloxane unit represented by the following formula 1: An optical modulation device, in which the absolute value of ΔT in the following formula 1 is 300% or less: [Chemical formula 1] (HRSiO ２／２ ) In Formula 1, R is an alkyl group, an alkoxy group, or an aryl group: [Formula 1] ##EQU00012## In Equation 1, T ２ is the transmittance at 90° C. when the light modulation device is placed between crossed polarizers after being maintained at 90° C. for 5 minutes, and T １ is the transmittance at 25° C. when the light modulation device is placed between crossed polarizers before being maintained at 90° C. for 5 minutes, and T １ and T ２ is the transmittance when the liquid crystal layer is in a vertically aligned state, and the liquid crystal layer is in the vertically aligned state while being maintained at 90° C. for 5 minutes.

2. The light modulating device of claim 1 , wherein the silicone polymer layer is a pressure sensitive adhesive layer or a glue layer.

3. The optical modulation device according to claim 1 , wherein the silicone polymer layer is formed on the surface of the first substrate, and an area of ​​the silicone polymer layer is 70% or more of an entire area of ​​the first substrate.

4. The light modulating device of claim 3 , wherein the silicone polymer layer is in contact with the liquid crystal layer.

5. The light modulation device of claim 1 , wherein no liquid crystal alignment film is present between the liquid crystal layer and the first substrate.

6. 2. The optical modulation device according to claim 1, wherein the ratio of the number of moles of the siloxane units of the chemical formula 1 to the number of moles of all the siloxane units of the polyorganosiloxane is 0.001 mol % or more and less than 100 mol %.

7. The light modulation device according to claim 1 , wherein the polyorganosiloxane has a linear or branched chain structure and is end-capped with a siloxane unit of the following chemical formula 2: [Chemical formula 2] (R １ ３ SiO １／２ ) In formula 2, R １ is a hydrogen atom, an alkyl group, an alkoxy group, or an aryl group.

8. 2. The light modulating device of claim 1, wherein the polyorganosiloxane further comprises a siloxane unit of the following formula 3: [Chemical formula 3] (R ２ ２ SiO ２／２ ) In formula 3, R ２ is an alkyl group, an alkoxy group, or an aryl group.

9. The light modulating device of claim 1 , wherein the polyorganosiloxane is represented by the following chemical formula 4: [Chemical formula 4] 【Chemistry 7】 In Formula 4, each R is independently an alkyl group, an alkoxy group, or an aryl group; m is a number in the range of 1 to 1,000; and n is a number in the range of 0 to 20,000.

10. 2. The light modulation device according to claim 1, wherein the content of the polyorganosiloxane having the siloxane unit of Chemical Formula 1 in the silicone polymer layer is 2% by weight or more.

11. The optical modulation device according to claim 1, wherein δ in the following formula 2 is 10.5 or more: [Formula 2] ##EQU00013## In Equation 2, M １ is the molar mass (g / mol) of the siloxane unit of the chemical formula 1, m is the number of moles of the siloxane unit of the chemical formula 1 in the polyorganosiloxane having the siloxane unit of the chemical formula 1, β is the content (wt%) of the polyorganosiloxane having the siloxane unit of the chemical formula 1 in the silicone polymer layer, M ２ is the molar mass (g / mol) of the polyorganosiloxane having the siloxane unit of formula 1.

12. The light modulation device according to claim 1 , further comprising a liquid crystal alignment film between the liquid crystal layer and the second substrate.

13. The light modulation device according to claim 12 , wherein the liquid crystal alignment film is a vertical alignment film.

14. 2. The optical modulation device according to claim 1, further comprising a partition-type spacer formed between said first and second substrates for maintaining a distance between said first and second substrates.

15. The light modulation device according to claim 1 , wherein the liquid crystal layer is initially in a vertically aligned state.

16. 10. The light modulation device of claim 1, wherein the liquid crystal layer is configured to be switchable between a homeotropic alignment state and a twisted alignment state.

17. 2. The optical modulation device according to claim 1, wherein the first and second substrates each have an in-plane retardation of 500 nm or more for light with a wavelength of 550 nm.

18. A window comprising a light modulating device according to any one of claims 1 to 17.

19. A sunroof comprising a light modulating device according to any one of claims 1 to 17.

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