Optical laminate and image display device

Abstract

The present invention addresses the problem of providing an optical laminate and an image display device capable of suppressing coloration of a display screen when used in an image display device having a viewing angle switching function. This optical laminate has a first light-absorbing anisotropic layer, a liquid crystal cell, and a second light-absorbing anisotropic layer in this order, wherein at least one of the first light-absorbing anisotropic layer and the second light-absorbing anisotropic layer is a specific light-absorbing anisotropic layer that satisfies all of the following requirements 1-3. Requirement 1: A dichroic material is contained. Requirement 2: the angle formed by the transmittance center axis of the light-absorbing anisotropic layer and the normal direction of the surface of the light-absorbing anisotropic layer is 0-40 DEG. Requirement 3: the difference in the degree of orientation of the light-absorbing anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm is 0.025 or less.

Description

Technical Field

[0001] The present invention relates to an optical laminate and an image display device. Background Art

[0002] Image display devices such as liquid crystal display devices and organic EL display devices are widely used as displays for smartphones, laptop computers, etc. In recent years, as these devices have become thinner and lighter and thus easier to carry, they are increasingly used in transportation means such as trains and airplanes, as well as in public places such as libraries and restaurants. Therefore, due to the necessity of protecting personal information and confidential information, etc., there is a demand for technologies that prevent the display content of image display devices from being peeked at by others.

[0003] For example, Patent Document 1 describes an optical laminate that at least sequentially includes a first light absorption anisotropic layer, one or more refractive index anisotropic layers containing a liquid crystal compound having a twisted structure, and a second light absorption anisotropic layer, wherein the refractive index anisotropic layer is in the form of a liquid crystal cell (for example, a TN liquid crystal cell capable of electrically switching birefringence, etc.) ([Claim 1][Claim 4][Claim 5]).

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: International Publication No. 2021 / 210359 Summary of the Invention

[0007] Technical Problem to be Solved by the Invention

[0008] The inventors of the present invention applied the optical laminate described in Patent Document 1 to an image display device and evaluated its characteristics. As a result, it was clarified that when a liquid crystal cell is used as the refractive index anisotropic layer to switch the viewing angle, there is room for improvement in the coloration of the display screen compared to an image display device without a viewing angle switching function.

[0009] Therefore, an object of the present invention is to provide an optical laminate and an image display device that can suppress the coloration of the display screen when used in an image display device having a viewing angle switching function.

[0010] Means for Solving the Technical Problem

[0011] As a result of intensive studies by the present inventors to achieve the above object, it has been found that when an optical laminate having a specific light absorption anisotropic layer satisfying a specified requirement in at least one of the first light absorption anisotropic layer and the second light absorption anisotropic layer is used together with a liquid crystal cell, coloration of the display screen can be suppressed when applied to an image display device having a viewing angle switching function, and thus the present invention has been completed.

[0012] That is, the present inventors have found that the above object can be solved by the following structure.

[0013] [1] An optical laminate having, in this order, a first light absorption anisotropic layer, a liquid crystal cell, and a second light absorption anisotropic layer,

[0014] At least one of the first light absorption anisotropic layer and the second light absorption anisotropic layer is a specific light absorption anisotropic layer that satisfies all of the following requirements 1 to 3.

[0015] Requirement 1: Contains a dichroic substance.

[0016] Requirement 2: The angle formed by the transmission axis center of the light absorption anisotropic layer and the normal direction of the surface of the light absorption anisotropic layer is 0° or more and 40° or less.

[0017] Requirement 3: The difference in the degree of orientation at wavelengths of 450 nm, 550 nm, and 650 nm of the light absorption anisotropic layer is 0.025 or less.

[0018] [2] The optical laminate according to [1], wherein the transmission axis center of any one of the first light absorption anisotropic layer and the second light absorption anisotropic layer is present in the in-plane direction of the light absorption anisotropic layer.

[0019] [3] The optical laminate according to [1] or [2], wherein the haze value of the specific light absorption anisotropic layer is 0.3% or less.

[0020] [4] The optical laminate according to any one of [1] to [3], wherein the specific light absorption anisotropic layer contains a polymer liquid crystal compound.

[0021] [5] The optical laminate according to any one of [1] to [4], wherein the specific light absorption anisotropic layer contains a fluorine-based vertical alignment agent having a borate group.

[0022] [6] The optical laminate according to any one of [1] to [5], wherein the liquid crystal cell is a VA mode and can switch the in-plane retardation at a wavelength of 550 nm between 0 nm and 120 to 160 nm or between 0 nm and 250 to 300 nm.

[0023] [7] The optical laminate according to any one of [1] to [5], wherein the liquid crystal cells are in the IPS mode, and the in-plane retardation at a wavelength of 550 nm is 120 to 160 nm or 250 to 300 nm.

[0024] [8] The optical laminate according to any one of [1] to [5], wherein the liquid crystal cells are in the TN mode, and the twist angle of the alignment can be switched between 0° and 90° or between 0° and 270°.

[0025] [9] An image display device having a viewing angle switching function, wherein the image display device has the optical laminate according to any one of [1] to [8].

[0026]

[10] The image display device according to [9], which can independently switch the viewing angles of a plurality of regions within the display screen.

[0027] Advantages of the Invention

[0028] According to the present invention, there can be provided an optical laminate and an image display device which, when used in an image display device having a viewing angle switching function, can suppress coloration of the display screen. Description of the Drawings

[0029] Figure 1 It is a conceptual diagram showing an example of an embodiment of an inorganic EL light-emitting element (so-called micro LED (light-emitting diode)). Detailed Embodiments

[0030] Hereinafter, the present invention will be described in detail.

[0031] The description of the constituent elements described below is based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

[0032] In addition, in this specification, the numerical range indicated by "~" means a range including the numerical values described before and after "~" as the lower limit value and the upper limit value.

[0033] In this specification, parallel and orthogonal respectively refer to ranges of parallel ±5° and orthogonal ±5°, rather than strictly parallel and orthogonal.

[0034] In this specification, regarding each component, one substance corresponding to each component can be used alone, or two or more can be used in combination. Here, regarding each component, when two or more substances are used in combination, unless otherwise specified, the content of the component refers to the total content of the substances used in combination.

[0035] Further, in the present specification, “(meth)acrylate” is a notation representing “acrylate” or “methacrylate”, “(meth)acrylic acid” is a notation representing “acrylic acid” or “methacrylic acid”, and “(meth)acryloyl” is a notation representing “acryloyl” or “methacryloyl”.

[0036] Further, in the present specification, Re(λ) and Rth(λ) respectively represent the in-plane retardation and the thickness-direction retardation at wavelength λ. Unless otherwise specified, the wavelength λ is set to 550 nm.

[0037] In the present invention, Re(λ) and Rth(λ) are values obtained by measurement at wavelength λ using AxoScan (manufactured by Axometrics). By inputting the average refractive index ((nx + ny + nz) / 3) and the film thickness (d (μm)) using AxoScan,

[0038] Slow axis direction (°)

[0039] Re(λ) = R0(λ)

[0040] Rth(λ) = ((nx + ny) / 2 - nz) × d.

[0041] In addition, R0(λ) represents a value calculated by AxoScan and refers to Re(λ).

[0042] Further, in the present specification, the refractive indices nx, ny, and nz are measured using an Abbe refractometer (NAR-4T, manufactured by ATAGO CO., LTD.) with a sodium lamp (λ = 589 nm) as the light source. When measuring the wavelength dependence, a multi-wavelength Abbe refractometer DR-M2 (manufactured by ATAGO CO., LTD.) can be used and measured in combination with an interference filter.

[0043] In addition, the values in the Polymer Handbook (JOHN WILEY&SONS, INC) and the catalogs of various optical films can be used. The following shows the values of the average refractive indices of main optical films: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), and polystyrene (1.59).

[0044] [Optical laminate]

[0045] The optical laminate of the present invention is an optical laminate having a first light absorption anisotropic layer, a liquid crystal cell, and a second light absorption anisotropic layer in this order.

[0046] Further, in the optical laminate of the present invention, at least one of the first light absorption anisotropic layer and the second light absorption anisotropic layer is a specific light absorption anisotropic layer that satisfies all of the following requirements 1 to 3.

[0047] Requirement 1: Contains a dichroic substance.

[0048] Requirement 2: The angle formed by the transmission axis center of the light absorption anisotropic layer and the normal direction of the surface of the light absorption anisotropic layer is 0° or more and 40° or less.

[0049] Requirement 3: The difference in the degree of orientation of the light absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm is 0.025 or less.

[0050] Here, the transmission axis center of the light absorption anisotropic layer refers to the direction that shows the highest transmittance when measuring the transmittance by changing the tilt angle (polar angle) and tilt direction (azimuth angle) of the light absorption anisotropic layer surface relative to the normal direction.

[0051] Specifically, the Mueller matrix at a wavelength of 550 nm is actually measured using AxoScan (manufactured by Axometrics). More specifically, during the measurement, first, find the azimuth angle of the tilt of the transmission axis center. Then, within the surface (a plane containing the transmission axis center and orthogonal to the layer surface) that includes the normal direction of the light absorption anisotropic layer along its azimuth angle, change the polar angle, which is the angle relative to the normal direction of the light absorption anisotropic layer surface, by 1° until -70 to 70°, actually measure the Mueller matrix at a wavelength of 550 nm, and derive the transmittance of the light absorption anisotropic layer. As a result, the direction with the highest transmittance is taken as the transmission axis center.

[0052] In addition, the transmission axis center refers to the direction of the absorption axis (the long axis direction of the molecule) of the dichroic substance contained in each light absorption anisotropic layer.

[0053] Further, the degree of orientation of the light absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm is the value calculated by the following method.

[0054] Specifically, using AxoScan (manufactured by Axometrics), measure the Mueller matrix every 5° within the range of -70 to 70° of the polar angle in the in-plane slow axis direction, and obtain kx(λ), ky(λ), and kz(λ) by fitting.

[0055] Next, calculate the absorption anisotropies Ao(λ) and Ae(λ) according to the following formulas (A) to (D), and calculate the degree of orientation S according to the following formula (E).

[0056] To(λ) = EXP{-4×π×(kx(λ)+ky(λ)) / 2×d / λ} (A)

[0057] Te(λ) = EXP{-4×π×kz(λ)×d / λ} (B)

[0058] Ao(λ) = -log(To(λ)) (C)

[0059] Ae(λ) = -log(Te(λ)) (D)

[0060] Orientation degree S(λ) = [Ao(λ) / Ae(λ) - 1] / [Ao(λ) / Ae(λ) + 2] (E)

[0061] Here, d represents the film thickness (nm) of the light absorption anisotropic layer, To(λ) and Te(λ) represent the transmittance, and Ao(λ) and Ae(λ) represent the absorbance.

[0062] In addition, the difference in the orientation degree (0.025 or less) specified in the above requirement 3 refers to the maximum difference among the differences in the orientation degree at each of the wavelengths of 450 nm and 550 nm, the differences in the orientation degree at each of the wavelengths of 450 nm and 650 nm, and the differences in the orientation degree at each of the wavelengths of 550 nm and 650 nm.

[0063] In the present invention, as described above, when an optical laminate in which at least one of the first light absorption anisotropic layer and the second light absorption anisotropic layer is a specific light absorption anisotropic layer is used, coloration of the display screen can be suppressed when applied to an image display device having a viewing angle switching function.

[0064] Although the detailed content is not yet clear, the present inventors presume as follows.

[0065] That is, it is considered that by satisfying the above requirements 1 to 3 (especially requirement 3) with the specific light absorption anisotropic layer, the influence of the state of the phase difference in the liquid crystal cell (for example, the state where the in-plane phase difference is λ / 2, etc.), that is, the deviation of the absorption amounts of blue light, green light, and red light in the light absorption anisotropic layer becomes smaller, and thus coloration of the display screen can be suppressed.

[0066] Hereinafter, each layer included in the optical laminate of the present invention will be described in detail.

[0067] [First light absorption anisotropic layer and second light absorption anisotropic layer]

[0068] As long as at least one of the first light absorption anisotropic layer and the second light absorption anisotropic layer included in the optical laminate of the present invention is a specific light absorption anisotropic layer, there is no particular limitation, and it may be a mode in which both the first light absorption anisotropic layer and the second light absorption anisotropic layer are specific light absorption anisotropic layers; a mode in which the first light absorption anisotropic layer is a specific light absorption anisotropic layer and the second light absorption anisotropic layer is a light absorption anisotropic layer that does not belong to the specific light absorption anisotropic layer (hereinafter, also simply referred to as "other light absorption anisotropic layer"); and a mode in which the first light absorption anisotropic layer is an other light absorption anisotropic layer and the second light absorption anisotropic layer is a specific light absorption anisotropic layer.

[0069] <Specific light absorption anisotropic layer>

[0070] As described above, the specific light absorption anisotropic layer is a light absorption anisotropic layer containing a dichroic material (reference requirement 1), preferably a light absorption anisotropic layer containing a liquid crystal compound together with the dichroic material, and more preferably a layer in which the alignment states of the liquid crystal compound and the dichroic material are fixed.

[0071] Also, as described above, the angle formed by the center axis of transmittance of the specific light absorption anisotropic layer and the normal direction of the surface of the specific light absorption anisotropic layer is 0° or more and 40° or less (reference requirement 2), but from the reason that the coloration of the display screen can be further suppressed, it is preferably 0° or more and 35° or less, more preferably 0° or more and 20° or less, and further preferably 0° or more and less than 15°.

[0072] Moreover, as described above, the difference in degree of alignment (ΔS) of the specific light absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm is 0.025 or less (reference requirement 3), but from the reason that the coloration of the display screen can be further suppressed, it is preferably 0.020 or less, and more preferably 0.010 to 0.000.

[0073] In the present invention, from the reason of easy image recognition, the haze value of the specific light absorption anisotropic layer is preferably 0.3% or less.

[0074] Here, the haze value is the haze measured according to "Method for Measuring Haze of Transparent Plastics" of JIS K7136:2000, and is the value measured using a haze meter (for example, NDH2000 (manufactured by NIPPON DENSHOKU INDUSTRIES Co., LTD.) etc.) in an environment of 25°C and a relative humidity of 55%.

[0075] <Other light absorption anisotropic layer>

[0076] The other light absorption anisotropic layer is a light absorption anisotropic layer that does not belong to the specific light absorption anisotropic layer. For example, absorption-type polarizers and reflection-type polarizers known in the past can be used.

[0077] Here, as the absorption-type polarizer, iodine-based polarizers, dye-based polarizers using dichroic dyes, polyene-based polarizers, etc. can be used. Regarding iodine-based polarizers and dye-based polarizers, there are coating-type polarizers and stretching-type polarizers, both of which can be applied, but a polarizer made by adsorbing iodine or a dichroic dye on polyvinyl alcohol and stretching it is preferred.

[0078] Also, as the reflection-type polarizer, a polarizer formed by laminating films with different birefringences, a wire grid polarizer, a polarizer formed by combining a cholesteric liquid crystal having a selective reflection region and a quarter-wave plate, etc. can be used.

[0079] Also, the other light absorption anisotropic layer is preferably a light absorption anisotropic layer containing a dichroic substance, more preferably a light absorption anisotropic layer containing a dichroic substance and a liquid crystal compound, and further preferably a layer in which the orientation states of the liquid crystal compound and the dichroic substance are fixed, similarly to the specific light absorption anisotropic layer.

[0080] Also, the transmission rate central axis of the other light absorption anisotropic layer can exist in the in-plane direction of the other light absorption anisotropic layer.

[0081] Also, similarly to the specific light absorption anisotropic layer, the difference in the degree of orientation at wavelengths of 450 nm, 550 nm, and 650 nm of the other light absorption anisotropic layer is preferably 0.025 or less, more preferably 0.020 or less, and further preferably 0.010 to 0.000.

[0082] <Dichroic substance>

[0083] The dichroic substance contained in the specific light absorption anisotropic layer and the dichroic substance that can be contained in the other light absorption anisotropic layer both refer to substances whose absorbance varies depending on the direction. Also, the dichroic substance may or may not exhibit liquid crystallinity.

[0084] The dichroic substance is not particularly limited, and examples include visible light absorption substances (dichroic pigments), luminescent substances (fluorescent substances, phosphorescent substances), ultraviolet absorption substances, infrared absorption substances, nonlinear optical substances, carbon nanotubes, and inorganic substances (such as quantum rods), etc. Dichroic substances (dichroic pigments) known in the past can be used.

[0085] Specifically, for example, paragraphs

[0067] to

[0071] of Japanese Patent Application Laid-Open No. 2013-228706, paragraphs

[0008] to

[0026] of Japanese Patent Application Laid-Open No. 2013-227532, paragraphs

[0008] to

[0015] of Japanese Patent Application Laid-Open No. 2013-209367, paragraphs

[0045] to

[0058] of Japanese Patent Application Laid-Open No. 2013-14883, paragraphs

[0012] to

[0029] of Japanese Patent Application Laid-Open No. 2013-109090, paragraphs

[0009] to

[0017] of Japanese Patent Application Laid-Open No. 2013-101328, paragraphs

[0051] to

[0065] of Japanese Patent Application Laid-Open No. 2013-37353, paragraphs

[0049] to

[0073] of Japanese Patent Application Laid-Open No. 2012-63387, paragraphs

[0016] to

[0018] of Japanese Patent Application Laid-Open No. Hei 11-305036, paragraphs

[0009] to

[0011] of Japanese Patent Application Laid-Open No. 2001-133630, paragraphs

[0030] to

[0169] of Japanese Patent Application Laid-Open No. 2011-215337, paragraphs

[0021] to

[0075] of Japanese Patent Application Laid-Open No. 2010-106242, paragraphs

[0011] to

[0025] of Japanese Patent Application Laid-Open No. 2010-215846, paragraphs

[0017] to

[0069] of Japanese Patent Application Laid-Open No. 2011-048311, paragraphs

[0013] to

[0133] of Japanese Patent Application Laid-Open No. 2011-213610, paragraphs

[0074] to

[0246] of Japanese Patent Application Laid-Open No. 2011-237513, paragraphs

[0005] to

[0051] of Japanese Patent Application Laid-Open No. 2016-006502, paragraphs

[0014] to

[0032] of Japanese Patent Application Laid-Open No. 2018-053167, paragraphs

[0014] to

[0033] of Japanese Patent Application Laid-Open No. 2020-11716, paragraphs

[0005] to

[0041] of International Publication No. 2016 / 060173, paragraphs

[0008] to

[0062] of International Publication No. 2016 / 136561, paragraphs

[0014] to

[0033] of International Publication No. 2017 / 154835, paragraphs

[0014] to

[0033] of International Publication No. 2017 / 154695, paragraphs

[0013] to

[0037] of International Publication No. 2017 / 195833, paragraphs

[0014] to

[0034] of International Publication No. 2018 / 164252, paragraphs

[0021] to

[0030] of International Publication No. 2018 / 186503, paragraphs

[0043] to

[0063] of International Publication No. 2019 / 189345, paragraphs

[0043] to

[0085] of International Publication No. 2019 / 225468, paragraphs

[0050] to

[0074] of International Publication No. 2020 / 004106The content described in paragraphs

[0015] to

[0038] etc. of International Publication No. 2021 / 044843.

[0086] As the dichroic substance, a dichroic azo pigment compound is preferred.

[0087] A dichroic azo pigment compound refers to an azo pigment compound whose absorbance varies depending on the direction. The dichroic azo pigment compound may or may not exhibit liquid crystallinity. When the dichroic azo pigment compound exhibits liquid crystallinity, it may exhibit either nematic or smectic. The temperature range showing the liquid crystal phase is preferably from room temperature (about 20 to 28 °C) to 300 °C, and more preferably from 50 to 200 °C from the viewpoints of operability and manufacturing applicability.

[0088] In the present invention, from the viewpoint of hue adjustment, it is preferred to use at least one pigment compound (first dichroic azo pigment compound) having a maximum absorption wavelength in the range of 560 to 700 nm and at least one pigment compound (second dichroic azo pigment compound) having a maximum absorption wavelength in the range of more than 455 nm and less than 560 nm.

[0089] In the present invention, three or more kinds of dichroic azo pigment compounds can be used in combination. For example, from the viewpoint of making the specific light absorption anisotropic layer and other light absorption anisotropic layers (hereinafter, when there is no need to particularly distinguish, they are collectively referred to as "light absorption anisotropic layers") approach black, it is preferred to use in combination the first dichroic azo pigment compound, the second dichroic azo pigment compound, and at least one pigment compound (third dichroic azo pigment compound) having a maximum absorption wavelength in the range of more than 380 nm and less than 455 nm.

[0090] In the present invention, it is preferred that the dichroic azo pigment compound has a crosslinkable group.

[0091] Examples of the crosslinkable group include (meth)acryloyl group, epoxy group, oxetanyl group, and styryl group, and among them, (meth)acryloyl group is preferred.

[0092] The content of the dichroic substance is not particularly limited, but from the reason of improving the orientation degree of the formed light absorption anisotropic layer, it is preferably 3% by mass or more, more preferably 8% by mass or more, further preferably 10% by mass or more, and particularly preferably 10 to 30% by mass based on the total mass of the light absorption anisotropic layer. In addition, when using a plurality of dichroic substances in combination, the total amount of the plurality of dichroic substances is preferably within the above range.

[0093] In particular, considering the reason that the difference in the degree of orientation of the light absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm can be set to 0.025 or less, the content of the first dichroic azo pigment compound is preferably 9 to 12% by mass relative to the total mass of the light absorption anisotropic layer, the content of the second dichroic azo pigment compound is preferably 1 to 2% by mass relative to the total mass of the light absorption anisotropic layer, and the content of the third dichroic azo pigment compound is preferably 4 to 7% by mass relative to the total mass of the light absorption anisotropic layer.

[0094] <Liquid crystal compound>

[0095] As described above, the light absorption anisotropic layer preferably contains a liquid crystal compound. Thereby, precipitation of the dichroic substance can be suppressed, and the dichroic substance can be oriented with a higher degree of orientation.

[0096] As the liquid crystal compound, either a polymer liquid crystal compound or a low-molecular liquid crystal compound can be used. In particular, for a specific light absorption anisotropic layer, from the viewpoint of being able to improve the degree of orientation, a polymer liquid crystal compound is preferably used.

[0097] Moreover, a polymer liquid crystal compound and a low-molecular liquid crystal compound can be used in combination.

[0098] Herein, the "polymer liquid crystal compound" refers to a liquid crystal compound having a repeating unit in its chemical structure.

[0099] Herein, the "low-molecular liquid crystal compound" refers to a liquid crystal compound not having a repeating unit in its chemical structure.

[0100] As the polymer liquid crystal compound, for example, a thermotropic liquid crystalline polymer described in JP-A-2011-237513, a polymer liquid crystal compound described in paragraphs

[0012] to

[0042] of WO 2018 / 199096, etc. can be cited.

[0101] As the low-molecular liquid crystal compound, for example, the liquid crystal compounds described in paragraphs

[0072] to

[0088] of JP-A-2013-228706 can be cited. Among them, a liquid crystal compound showing a smectic phase is preferred.

[0102] Herein, as the smectic phase, for example, a smectic A phase, a smectic C phase, etc. can be cited, but a higher-order smectic phase (for example, a smectic B phase, a smectic E phase, a smectic F phase, a smectic G phase, a smectic H phase, a smectic I phase, a smectic J phase, a smectic K phase, a smectic L phase, etc.) can also be used.

[0103] Moreover, in addition to the smectic phase, a nematic phase can also be exhibited.

[0104] In the present invention, from the viewpoint of the reason for higher contrast, the liquid crystal compound is preferably a liquid crystal compound showing any one of the smectic B phase, E phase, F phase, G phase, H phase, I phase, J phase, K phase, and L phase.

[0105] As the smectic liquid crystal compound, a compound represented by the following formula (A-1) is preferred.

[0106] Formula (A-1)

[0107] Q1-V1-SP1-X1-(Ma-La)na-X2-SP2-V2-Q2

[0108] In formula (A-1), Q1 and Q2 each independently represent a polymerizable group.

[0109] Moreover, V1, V2, X1, and X2 each independently represent a single bond or a divalent linking group.

[0110] Moreover, SP1 and SP2 each independently represent a divalent spacer group.

[0111] Moreover, Ma represents an aromatic ring, an aliphatic ring, or a heterocyclic ring which may have a substituent. Herein, a plurality of Ma may be the same or different.

[0112] Moreover, La represents a single bond or a divalent linking group. Herein, a plurality of La may be the same or different.

[0113] Moreover, na represents an integer of 2 to 10.

[0114] As the polymerizable group represented by Q1 and Q2, a polymerizable group capable of radical polymerization (radical polymerizable group) or a polymerizable group capable of cationic polymerization (cationic polymerizable group) is preferred.

[0115] As the radical polymerizable group, a known radical polymerizable group can be used, and acryloyloxy or methacryloyloxy is preferred. It is known that the polymerization rate of acryloyloxy is generally fast, and from the viewpoint of improving productivity, acryloyloxy is preferred, but methacryloyloxy can also be used as the polymerizable group.

[0116] As the cationic polymerizable group, a known cationic polymerizable group can be used. For example, an alicyclic ether group, a cyclic acetal group, a cyclic lactone group, a cyclic thioether group, a spiro orthoester group, and a vinyloxy group can be mentioned. Among them, an alicyclic ether group or a vinyloxy group is preferred, and an epoxy group, an oxetanyl group, or a vinyloxy group is more preferred.

[0117] As examples of the preferred polymerizable group, polymerizable groups represented by the following formulas (P-1) to (P-30) can be mentioned.

[0118] [Chemical Formula 1]

[0119]

[0120] In the above formulas (P-1) to (P-30), R P represents a hydrogen atom, a halogen atom, a linear, branched or cyclic alkylene group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 1 to 20 carbon atoms, a heterocyclic group (also referred to as a heterocyclic radical), a cyano group, a hydroxyl group, a nitro group, a carboxyl group, an aryloxy group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an amino group (including anilino), an ammonium group, an acylamino group, an aminocarbonylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkyl or arylsulfonylamino group, a mercapto group, an alkylthio group, an arylthio group, a heterocyclic thio group, a sulfamoyl group, a sulfo group, an alkyl or arylsulfinyl group, an alkyl or arylsulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an aryl or heterocyclic azo group, an imide group, a phosphino group, an oxyphosphino group, an oxyphosphinooxy group, an oxyphosphinoamino group, a phosphonyl group, a silyl group, a hydrazino group, a ureido group, a boronic acid group (-B(OH)2), a phosphoric acid group (-OPO(OH)2), or a sulfuric acid group (-OSO3H). Multiple R P may be the same or different from each other.

[0121] Among them, as the radically polymerizable group, a vinyl group represented by the above formula (P-1), a butadienyl group represented by the above formula (P-2), a (meth)acryloyl group represented by the above formula (P-4), a (meth)acrylamide group represented by the above formula (P-5), a vinyl acetate group represented by the above formula (P-6), a fumaric acid diester group represented by the above formula (P-7), a styryl group represented by the above formula (P-8), a vinylpyrrolidone group represented by the above formula (P-9), maleic anhydride represented by the above formula (P-11), or a maleimide group represented by the above formula (P-12) is preferred. As the cationically polymerizable group, a vinyl ether group represented by the above formula (P-18), an epoxy group represented by the above formula (P-19), or an oxetanyl group represented by the above formula (P-20) is preferred.

[0122] In the formula (A-1), as the divalent linking group represented by one of V1, V2, X1, X2, and La, for example, -O-, -(CH2) g -, -(CF2) g -, -Si(CH3)2-, -(Si(CH3)2O) g -, -(OSi(CH3)2) g-(g is an integer from 1 to 10.), -N(Z)-, -C(Z)=C(Z')-, -C(Z)=N-, -N=C(Z)-, -C(Z)2-C(Z')2-, -C(O)-, -OC(O)-, -C(O)O-, -O-C(O)O-, -N(Z)C(O)-, -C(O)N(Z)-, -C(Z)=C(Z')-C(O)O-, -O-C(O)-C(Z)=C(Z')-, -C(Z)=N-, -N=C(Z)-, -C(Z)=C(Z')-C(O)N(Z"), -N(Z")-C(O)-C(Z)=C(Z')-, -C(Z)=C(Z')-C(O)-S-, -S-C(O)-C(Z)=C(Z')-, -C(Z)=N-N=C(Z')-(Z, Z', Z" independently represent hydrogen, an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group, an aryl group, a cyano group or a halogen atom.), -C≡C-, -N=N-, -S-, -S(O)-, -S(O)(O)-, -(O)S(O)O-, -O(O)S(O)O-, -SC(O)- and -C(O)S-, etc. V1, V2, X1, X2 and La may be groups formed by combining two or more of these groups.

[0123] In formula (A-1), as the divalent spacer group represented by SP1 and SP2, for example, a linear, branched or cyclic alkylene group having 1 to 50 carbon atoms, or a heterocyclic group having 1 to 20 carbon atoms can be cited.

[0124] The carbon atoms of the above-mentioned alkylene group and heterocyclic group may be -O-, -Si(CH3)2-, -(Si(CH3)2O) g -, -(OSi(CH3)2) g-(g is an integer from 1 to 10.), -N(Z)-, -C(Z)=C(Z')-, -C(Z)=N-, -N=C(Z)-, -C(Z)2-C(Z')2-, -C(O)-, -OC(O)-, -C(O)O-, -O-C(O)O-, -N(Z)C(O)-, -C(O)N(Z)-, -C(Z)=C(Z')-C(O)O-, -O-C(O)-C(Z)=C(Z')-, -C(Z)=N-, -N=C(Z)-, -C(Z)=C(Z')-C(O)N(Z''), -N(Z'')-C(O)-C(Z)=C(Z')-, -C(Z)=C(Z')-C(O)-S-, -S-C(O)-C(Z)=C(Z')-, -C(Z)=N-N=C(Z')-(Z, Z', Z'' independently represent hydrogen, an alkyl group with 1 to 4 carbon atoms, a cycloalkyl group, an aryl group, a cyano group or a halogen atom.), -C≡C-, -N=N-, -S-, -C(S)-, -S(O)-, -SO2-, -(O)S(O)O-, -O(O)S(O)O-, -SC(O)- and -C(O)S-, and is substituted by a group formed by combining two or more of these groups.

[0125] The hydrogen atoms of the above-mentioned alkylene group and heterocyclic group may be substituted by a halogen atom, a cyano group, -Z H , -OH, -OZ H , -COOH, -C(O)Z H , -C(O)OZ H , -OC(O)Z H , -OC(O)OZ H , -NZ H Z H ', -NZ H C(O)Z H ', -NZ H C(O)OZ H ', -C(O)NZ H Z H ', -OC(O)NZ H Z H ', -NZ H C(O)NZ H 'OZ H '', -SH, -SZ H , -C(S)Z H , -C(O)SZ H , -SC(O)Z H substituted. Among them, Z H , Z H, "Z" each independently represents an alkyl group, a halogenated alkyl group having 1 to 10 carbon atoms, -L-Q (L represents a single bond or a divalent linking group. Specific examples of the divalent linking group are the same as those of V1 described above. Q represents a crosslinkable group, and examples of the polymerizable group represented by Q1 or Q2 can be cited, and the polymerizable groups represented by the above formulas (P-1) to (P-30) are preferred).

[0126] In formula (A-1), MA represents an aromatic ring, an aliphatic ring or a heterocyclic ring which may have substituents, preferably a 4- to 15-membered ring. MA may be a monocyclic ring or a fused ring, and a plurality of MAs may be the same or different.

[0127] Examples of the aromatic ring represented by MA include phenylene, naphthylene, fluorene-diyl, anthracene-diyl, and tetracene-diyl. From the viewpoints of the diversity of the mesogenic skeleton design and the availability of raw materials, etc., phenylene and naphthylene are preferred.

[0128] Examples of the aliphatic ring represented by MA include cyclopentylene and cyclohexylene, etc., and the carbon atoms may be substituted by -O-, -Si(CH3)2-, -N(Z)-, -C(O)-, (Z independently represents hydrogen, an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group, an aryl group, a cyano group or a halogen atom), -S-, -C(S)-, -S(O)- and -SO2-, and groups formed by combining two or more of these groups.

[0129] Examples of the atoms other than carbon constituting the heterocyclic ring represented by MA include a nitrogen atom, a sulfur atom and an oxygen atom. When the heterocyclic ring has a plurality of ring-constituting atoms other than carbon, these atoms may be the same or different. Specific examples of the heterocyclic ring include, for example, pyridylene (pyridine-diyl), pyridazine-diyl, imidazole-diyl, thienylene (thiophene-diyl), quinolinylene (quinoline-diyl), isoquinolinylene (isoquinoline-diyl), oxazole-diyl, thiazole-diyl, oxadiazole-diyl, benzothiazole-diyl, benzothiadiazole-diyl, phthalimide-diyl, thienothiazole-diyl, thiazolothiazole-diyl, thienothiophene-diyl and thienooxazole-diyl, the following structures (II-1) to (II-4), etc.

[0130] [Chemical formula 2]

[0131]

[0132] In formulas (II-1) to (II-4), D1 represents -S-, -O- or NR 11 -, R 11 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

[0133] Y1 represents an aromatic hydrocarbon group having 6 to 12 carbon atoms or an aromatic heterocyclic group having 3 to 12 carbon atoms.

[0134] Z1, Z2, and Z3 each independently represent a hydrogen atom, an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, -NR 12 R 13 or -SR 12 . Herein, Z 1 and Z 2 may be bonded to each other to form an aromatic ring or an aromatic heterocyclic ring, and R 12 and R 13 each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

[0135] A1 and A2 each independently represent a group selected from the group consisting of -O-, -NR 21 -(R 21 represents a hydrogen atom or a substituent.), -S-, and -CO-.

[0136] E represents a non-metal atom of Group 14 to 16 to which a hydrogen atom or a substituent can be bonded.

[0137] Ax represents an organic group having 2 to 30 carbon atoms having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring,

[0138] Ay represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or an organic group having 2 to 30 carbon atoms having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring. The aromatic rings of Ax and Ay may have substituents, and Ax and Ay may be bonded to form a ring.

[0139] D2 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent.

[0140] In formula (II-2), when Y1 is an aromatic hydrocarbon group having 6 to 12 carbon atoms, it may be monocyclic or polycyclic. When Y2 is an aromatic heterocyclic group having 3 to 12 carbon atoms, it may be monocyclic or polycyclic.

[0141] In formula (II-2), when A1 and A2 represent -NR 21 -, as the substituent of R 21 , for example, the description in paragraphs 0035 to 0045 of Japanese Patent Application Laid-Open No. 2008-107767 can be referred to, and the content thereof is incorporated herein.

[0142] In formula (II-2), when X is a non-metallic atom of Groups 14 to 16 to which a substituent can be bonded, it is preferably =O, =S, =NR', =C(R')R'. R' represents a substituent, and as the substituent, for example, reference can be made to the descriptions in paragraphs

[0035] to

[0045] of JP-A-2008-107767, and it is preferably a nitrogen atom.

[0143] Regarding MA in formula (A-1), as substituents that an aromatic ring, aliphatic ring or heterocyclic ring may have, for example, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 1 to 20 carbon atoms, a heterocyclic group (also referred to as a heterocyclic radical), a cyano group, a hydroxyl group, a nitro group, a carboxyl group, an aryloxy group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an amino group (including an anilino group), an ammonium group, an acylamino group, an aminocarbonylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkyl or arylsulfonylamino group, a mercapto group, an alkylthio group, an arylthio group, a heterocyclic thio group, a sulfamoyl group, a sulfo group, an alkyl or arylsulfinyl group, an alkyl or arylsulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an aryl or heterocyclic azo group, an imide group, a phosphino group, an oxyphosphino group, an oxyphosphinooxy group, an oxyphosphinoamino group, a phosphinyl group, a silyl group, a hydrazino group, a ureido group, a boronic acid group (-B(OH)2), a phosphoric acid group (-OPO(OH)2), a sulfuric acid group (-OSO3H), other known substituents, etc. can be mentioned.

[0144] In addition, the details of the substituents are described in paragraph

[0023] of JP-A-2007-234651.

[0145] In formula (A-1), na represents an integer of 2 to 10, more preferably an integer of 2 to 8.

[0146] As smectic liquid crystal compounds, for example, the compounds described in paragraphs

[0033] to

[0039] of JP-A-2008-19240, paragraphs

[0037] to

[0041] of JP-A-2008-214269, paragraphs

[0033] to

[0040] of JP-A-2006-215437 or the structures shown below can be mentioned, but are not limited thereto.

[0147] [Chemical formula 3]

[0148]

[0149] [Chemical formula 4]

[0150]

[0151] [Chemical Formula 5]

[0152]

[0153] [Chemical Formula 6]

[0154]

[0155] n m R 4 4 H 4 6 H 4 10 H 6 10 H 6 12 H 4 8 OCH3 4 12 OCH3 6 10 Br 6 12 Br 8 12 OCH3

[0156] [Chemical Formula 7]

[0157]

[0158] SP L R -(CH2)4- -(CH2)3- H -(CH2)4- -(CH2)3- Br -(CH2)4- -(CH2)3- OCH3 -CH2CH(CH3)CH2- -(CH2)3- H -(CH2CH2O)2CH2CH3- -(CH2)3- H -(CH2CH2O)2CH2CH3- -(CH2CH2O)2CH2CH3- H

[0159] [Chemical Formula 8]

[0160]

[0161] The content of the smectic liquid crystal compound is preferably 50 to 99% by mass, more preferably 60 to 95% by mass, relative to the total solid component mass of the liquid crystal composition.

[0162] The content of the liquid crystal compound is not particularly limited, and is preferably 50 to 99% by mass, more preferably 75 to 90% by mass, relative to the total mass of the light absorption anisotropic layer.

[0163] <Vertical alignment agent>

[0164] In the present invention, considering the reason that the planar deterioration caused by alignment disorder can be suppressed, the light absorption anisotropic layer (especially, a specific light absorption anisotropic layer) preferably contains a fluorine-based vertical alignment agent having a boronic acid group.

[0165] As the fluorine-based vertical alignment agent having a boronic acid group, a copolymer having a repeating unit A represented by the following formula (A-1) and a repeating unit B represented by the following formula (B-1) can be cited.

[0166] [Chemical Formula 9]

[0167]

[0168] In the above formula (A-1),

[0169] R 1 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.

[0170] LF 1 represents a single bond or a divalent linking group.

[0171] RF 1Represents a group containing a fluorine atom.

[0172] Moreover, in the above formula (B-1),

[0173] R 2 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.

[0174] L 2 represents a single bond or a divalent linking group selected from the group consisting of -O-, -S-, -COO-, -OCO-, -CONR L1 -, -NR L1 COO-, -CR L1 N-, a substituted or unsubstituted divalent aliphatic group, a substituted or unsubstituted divalent aromatic group, and a combination thereof, where R L1 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.

[0175] R 3 and R 4 each independently represent a hydrogen atom, or a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, R 3 and R 4 may be connected to each other via an alkylene linking group, an arylene linking group, or a linking group composed of a combination thereof.

[0176] In the above formula (A-1), as described above, R 1 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, but among them, a hydrogen atom or an alkyl group having 1 to 10 carbon atoms is preferred, a hydrogen atom or an alkyl group having 1 to 4 carbon atoms is more preferred, and a hydrogen atom or a methyl group is further preferred.

[0177] Moreover, in the above formula (A-1), as described above, LF 1 represents a single bond or a divalent linking group, and among them, a divalent linking group selected from the group consisting of -0-, -COO-, -OCO-, a divalent aliphatic group, and a combination thereof is preferred. In addition, -COO- means that the carbon to which R 1 is bonded is bonded to C=0 and RF 1 is bonded to O, and -OCO- means that the carbon to which R 1 is bonded is bonded to O and RF 1 is bonded to C=O.

[0178] Here, as the divalent aliphatic group, a divalent aliphatic chain group or a divalent aliphatic cyclic group can be mentioned. As the divalent aliphatic chain group, an alkylene group having 1 to 20 carbon atoms is preferable, and an alkylene group having 1 to 10 carbon atoms is more preferable. As the divalent aliphatic cyclic group, a cycloalkylene group having 3 to 20 carbon atoms is preferable, and a cycloalkylene group having 3 to 15 carbon atoms is more preferable.

[0179] Among these, as LF 1 , -COO- or -OCO- is preferable, and -COO- is more preferable.

[0180] And, in the above formula (A-1), as described above, RF 1 represents a group containing a fluorine atom. Among them, an alkyl group having 1 to 20 carbon atoms in which at least one hydrogen atom is substituted by a fluorine atom (hereinafter, also referred to as "fluoroalkyl") is preferable, an alkyl group having 1 to 18 carbon atoms is more preferable, and an alkyl group having 2 to 15 carbon atoms is further preferable.

[0181] And, it is also preferable that the above fluoroalkyl contains at least one -CF3 group.

[0182] And, the number of fluorine atoms is preferably 1 to 25, more preferably 3 to 21, and most preferably 5 to 21.

[0183] In the present invention, the repeating unit represented by the above formula (A-1) is preferably a repeating unit represented by the following formula (A-1-1).

[0184] [Chemical formula 10]

[0185]

[0186] In the above formula (A-1-1), R 1 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms in the same manner as R 1 in the above formula (A-1), and the preferred mode is also the same.

[0187] And, in the above formula (A-1-1), ma and na each independently represent an integer of 0 to 19. Among them, from the viewpoint of obtaining raw materials and the like, ma is preferably an integer of 1 to 8, more preferably an integer of 1 to 5. And na is preferably an integer of 1 to 15, more preferably an integer of 1 to 12, further preferably an integer of 2 to 10, and most preferably an integer of 5 to 7. Among them, ma and na represent an integer of 0 to 19 in total.

[0188] As monomers for forming the repeating units represented by the above formula (A-1) or (A-1-1), specifically, for example, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3,3-pentafluoropropyl (meth)acrylate, 2-(perfluorobutyl)ethyl (meth)acrylate, 2-(perfluorohexyl)ethyl (meth)acrylate, 2-(perfluorooctyl)ethyl (meth)acrylate, 2-(perfluorodecyl)ethyl (meth)acrylate, 2-(perfluoro-3-methylbutyl)ethyl (meth)acrylate, 2-(perfluoro-5-methylhexyl)ethyl (meth)acrylate, 2-(perfluoro-7-methyl octyl)ethyl (meth)acrylate, 3-perfluorobutyl-2-hydroxypropyl (meth)acrylate, 3-perfluorohexyl-2-hydroxypropyl (meth)acrylate, 3-perfluorooctyl-2-hydroxypropyl (meth)acrylate, 3-(perfluoro-3-methylbutyl)-2-hydroxypropyl (meth)acrylate, 3-(perfluoro-5-methylhexyl)-2-hydroxypropyl (meth)acrylate, 3-(perfluoro-7-methyl octyl)-2-hydroxypropyl (meth)acrylate, etc. can be cited.

[0189] In the above formula (B-1), as described above, R 2 each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, among which, a hydrogen atom or an alkyl group having 1 to 10 carbon atoms is preferred, an alkyl group having 1 to 4 carbon atoms is more preferred, and a hydrogen atom or a methyl group is further preferred.

[0190] And, in the above formula (B-1), as described above, L 2 represents a single bond or a divalent linking group selected from the group consisting of -O-, -S-, -COO-, -OCO-, -CONR L1 -, -NR L1 COO-, -CR L1 N-, a substituted or unsubstituted divalent aliphatic group, a substituted or unsubstituted divalent aromatic group, and combinations thereof, and R L1 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.

[0191] Here, as the substituted or unsubstituted divalent aliphatic group represented by one mode of L 2 for example, an alkylene group having 1 to 20 carbon atoms that may have a substituent or a cycloalkylene group having 3 to 20 carbon atoms that may have a substituent (for example, cyclohexylene) etc. can be cited. Among them, an alkylene group having 1 to 15 carbon atoms is preferred, an alkylene group having 1 to 8 carbon atoms is more preferred, and methylene, ethylene, propylene, and butylene are further preferred.

[0192] And, as L 2The substituted or unsubstituted divalent aromatic group represented by one mode may be a divalent aromatic hydrocarbon group which may have a substituent or a divalent aromatic heterocyclic group which may have a substituent. As the divalent aromatic hydrocarbon group, for example, a group obtained by removing one hydrogen atom from each of two carbon atoms constituting the ring structure of an aromatic hydrocarbon ring such as a benzene ring, a naphthalene ring, an anthracene ring, a triphenylene ring, or a fluorene ring can be mentioned. Among them, a phenylene group or a naphthylene group obtained by removing one hydrogen atom from each of two carbon atoms constituting the ring structure of a benzene ring or a naphthalene ring is preferable. On the other hand, as the divalent aromatic heterocyclic group, a group obtained by removing one hydrogen atom from each of two carbon atoms constituting the ring structure of an aromatic heterocyclic ring such as a furan ring, a pyrrole ring, a thiophene ring, a pyridine ring, a thiazole ring, a benzothiazole ring, an oxadiazole ring, a thiazolothiazole ring, or a phenanthroline ring can be mentioned.

[0193] In addition, as the substituents that the divalent aliphatic group or the divalent aromatic group may have, for example, an alkyl group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, an alkylamino group, a dialkylamino group, an alkylamide group, an alkenyl group, an alkynyl group, a halogen atom, a cyano group, a nitro group, an alkylthiol group, and an N-alkylcarbamate group can be mentioned.

[0194] And, the above-mentioned R L1 The alkyl group having 1 to 20 carbon atoms represented by one mode is preferably an alkyl group having 1 to 6 carbon atoms. Specifically, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a n-pentyl group, and a n-hexyl group can be mentioned.

[0195] And, in the above formula (B-1), as described above, R 3 and R 4 each independently represent a hydrogen atom, or a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, and R 3 and R 4 may be connected to each other via an alkylene linking group, an arylene linking group, or a linking group composed of a combination thereof.

[0196] As the substituted or unsubstituted aliphatic hydrocarbon group represented by one mode of R 3 and R 4 a substituted or unsubstituted alkyl group, alkenyl group, or alkynyl group can be mentioned.

[0197] As the alkyl group, specifically, for example, there may be mentioned linear, branched and cyclic alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, hexadecyl, octadecyl, eicosyl, isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl, 1-methylbutyl, isohexyl, 2-methylhexyl, cyclopentyl, cyclohexyl, 1-adamantyl, 2-norbornyl, etc.

[0198] As the alkenyl group, specifically, for example, there may be mentioned linear, branched and cyclic alkenyl groups such as vinyl, 1-propenyl, 1-butenyl, 1-methyl-1-propenyl, 1-cyclopentenyl, 1-cyclohexenyl, etc.

[0199] As the alkynyl group, specifically, for example, there may be mentioned ethynyl, 1-propynyl, 1-butynyl, 1-octynyl, etc.

[0200] As R 3 and R 4 The substituted or unsubstituted aryl group represented by one mode, for example, there can be mentioned aryl groups formed by fusing 1 to 4 benzene rings, aryl groups formed by fusing a benzene ring and an unsaturated five-membered ring. Specifically, there can be mentioned phenyl, naphthyl, anthryl, phenanthryl, indenyl, acenaphthylenyl, fluorenyl, pyrenyl, etc.

[0201] As R 3 and R 4 The substituted or unsubstituted heteroaryl group represented by one mode, for example, there can be mentioned a group obtained by removing 1 hydrogen atom from the following heteroaromatic ring and using it as a heteroaryl group, and the heteroaromatic ring contains 1 or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom.

[0202] As the heteroaromatic ring containing 1 or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom, specifically, for example, there can be mentioned pyrrole, furan, thiophene, pyrazole, imidazole, triazole, oxazole, isoxazole, oxadiazole, thiazole, thiadiazole, indole, carbazole, benzofuran, dibenzofuran, thianthrene, dibenzothiophene, indazole benzimidazole, anthranil, benzisoxazole, benzoxazole, benzothiazole, purine, pyridine, pyridazine, pyrimidine, pyrazine, triazine, quinoline, acridine, isoquinoline, phthalazine, quinazoline, quinoxaline, naphthyridine, phenanthroline, pteridine, etc.

[0203] As R 3 and R 4 The substituents that can be possessed, for example, there can be mentioned alkyl group, alkoxy group, alkylcarbonyl group, alkoxycarbonyl group, alkylcarbonyloxy group, alkylamino group, dialkylamino group, alkylamide group, alkenyl group, alkynyl group, halogen atom, cyano group, nitro group, alkylthiol group and N-alkylcarbamate group, etc.

[0204] As the monomer for forming the repeating unit represented by the above formula (B-1), specifically, for example, monomers represented by the following formulas II-1 to II-12 can be cited.

[0205] [Chemical formula 11]

[0206]

[0207] When the light absorption anisotropic layer contains a vertical alignment agent, the content of the vertical alignment agent is preferably 0.1 to 400% by mass, more preferably 0.5 to 350% by mass, based on the total mass of the liquid crystal compound.

[0208] The vertical alignment agent can be used alone or in combination of two or more. When using two or more vertical alignment agents, it is preferred that their total amount is within the above range.

[0209] <Composition for forming a light absorption anisotropic layer>

[0210] The light absorption anisotropic layer is preferably formed using a composition for forming a light absorption anisotropic layer containing a dichroic substance and a liquid crystal compound.

[0211] The composition for forming a light absorption anisotropic layer preferably contains a solvent and the like described later in addition to the dichroic substance and the liquid crystal compound, and may further contain the above other components.

[0212] As the dichroic substance contained in the composition for forming a light absorption anisotropic layer, a dichroic substance that can be contained in the light absorption anisotropic layer can be cited.

[0213] The content of the dichroic substance relative to the total solid content mass of the composition for forming a light absorption anisotropic layer is preferably the same as the content of the dichroic substance relative to the total mass of the light absorption anisotropic layer.

[0214] Here, the "total solid content in the composition for forming a light absorption anisotropic layer" refers to the components other than the solvent. Specific examples of the solid components include a dichroic substance, a liquid crystal compound, and the above other components.

[0215] The liquid crystal compound and other components that can be contained in the composition for forming a light absorption anisotropic layer are the same as the liquid crystal compound and other components that can be contained in the light absorption anisotropic layer, respectively.

[0216] Preferably, the content of the liquid crystal compound and other components relative to the total solid content mass of the composition for forming a light absorption anisotropic layer is the same as the content of the liquid crystal compound and other components relative to the total mass of the light absorption anisotropic layer, respectively.

[0217] From an operational perspective, the composition for forming the light absorption anisotropic layer preferably contains a solvent.

[0218] Examples of the solvent include organic solvents such as ketones, ethers, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated carbons, esters, alcohols, cellosolves, cellosolve acetates, sulfoxides, amides, and heterocyclic compounds, as well as water.

[0219] These solvents can be used alone or in combination of two or more.

[0220] Among these solvents, organic solvents are preferred, and halogenated carbons or ketones are more preferred.

[0221] When the composition for forming the light absorption anisotropic layer contains a solvent, the content of the solvent is preferably 80 to 99% by mass, more preferably 83 to 97% by mass, and further preferably 85 to 95% by mass relative to the total mass of the composition for forming the light absorption anisotropic layer.

[0222] The composition for forming the light absorption anisotropic layer may contain a polymerization initiator.

[0223] There is no particular limitation on the polymerization initiator, and a photosensitive compound, that is, a photoinitiator, is preferred.

[0224] As such a photoinitiator, commercially available products can also be used, and examples include Irgacure-184, Irgacure-907, Irgacure-369, Irgacure-651, Irgacure-819, Irgacure-OXE-01, and Irgacure-OXE-02 manufactured by BASF Corporation.

[0225] The polymerization initiator can be used alone or in combination of two or more.

[0226] When the composition for forming the light absorption anisotropic layer contains a polymerization initiator, the content of the polymerization initiator is preferably 0.01 to 30% by mass, more preferably 0.1 to 15% by mass relative to the total solid content of the composition for forming the light absorption anisotropic layer.

[0227] <Method for manufacturing the light absorption anisotropic layer>

[0228] The method for manufacturing the light absorption anisotropic layer is not particularly limited. From the viewpoint of achieving a higher degree of orientation of the dichroic substance, a method that preferably includes the following steps in sequence (hereinafter, also referred to as "this manufacturing method") is used: a step of coating a composition for forming a light absorption anisotropic layer containing a dichroic substance and a liquid crystal compound on an alignment film to form a coating film (hereinafter, also referred to as "coating film forming step"); and a step of aligning the liquid crystal component contained in the above coating film (hereinafter, also referred to as "alignment step").

[0229] In addition, the liquid crystal component is a component that contains not only the above liquid crystal compound but also a dichroic substance having liquid crystallinity.

[0230] Hereinafter, each step will be described.

[0231] The coating film forming step is a step of coating the above composition for forming a light absorption anisotropic layer on an alignment film to form a coating film.

[0232] By using a composition for forming a light absorption anisotropic layer containing the above solvent or a composition for forming a light absorption anisotropic layer that is made into a liquid material such as a molten liquid by heating the composition for forming a light absorption anisotropic layer, it is easy to coat the composition for forming a light absorption anisotropic layer on the alignment film.

[0233] As a coating method of the composition for forming a light absorption anisotropic layer, known methods such as a roll coating method, a gravure printing method, a spin coating method, a wire bar coating method, an extrusion coating method, a direct gravure coating method, an inverse gravure coating method, a die coating method, a spraying method, and an inkjet method can be cited.

[0234] The alignment film can be any film as long as it can align the liquid crystal component contained in the composition for forming a light absorption anisotropic layer.

[0235] It can be provided by methods such as rubbing treatment of the film surface with an organic compound (preferably a polymer), oblique vapor deposition of an inorganic compound, forming a layer having microgrooves, or accumulation of an organic compound (such as ω-tricosanoic acid, dimethyldioctadecylammonium chloride, methyl stearate) based on the Langmuir-Blodgett method (LB film). Moreover, an alignment film that generates an alignment function by applying an electric field, applying a magnetic field, or light irradiation is also known. Among them, in the present invention, from the viewpoint of ease of controlling the pretilt angle of the alignment film, an alignment film formed by rubbing treatment is preferred, and from the viewpoint of alignment uniformity, a photoalignment film formed by light irradiation is also preferred.

[0236] As the photoalignment film, a photoalignment film containing an azobenzene pigment or polyvinyl cinnamate is used.

[0237] Ultraviolet rays are irradiated from an inclined direction that forms an angle with the normal direction of the photo-alignment layer, generating an anisotropy with an inclination with respect to the normal direction of the photo-alignment layer, and causing the photo-absorption anisotropic layer to be aligned thereon, whereby the dichroic substance in the photo-absorption anisotropic layer can be aligned.

[0238] Moreover, a liquid crystal layer in which a liquid crystal compound is mixed-aligned can also be used as an alignment film.

[0239] The alignment step is a step of aligning the liquid crystal components (especially, dichroic substances) contained in the coating film. It is considered that in the alignment step, the dichroic substances are aligned along the liquid crystal compound aligned through the alignment film.

[0240] The alignment step may include a drying treatment. Through the drying treatment, components such as solvents can be removed from the coating film. The drying treatment can be carried out by a method of leaving the coating film at room temperature for a specified time (for example, natural drying), or by a method of heating and / or blowing air.

[0241] The alignment step preferably includes a heating treatment. Thereby, the dichroic substances contained in the coating film are further aligned, and the degree of alignment of the dichroic substances becomes further higher.

[0242] From the viewpoint of manufacturing applicability and the like, the heating treatment is preferably at 10 to 250 °C, more preferably at 25 to 190 °C. And, the heating time is preferably 1 to 300 seconds, more preferably 1 to 60 seconds.

[0243] Moreover, from the reason of easily making the difference in the degree of alignment of the manufactured photo-absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm be 0.025 or less, the heating treatment is preferably carried out multiple times (especially 2 times).

[0244] The alignment step may include a cooling treatment implemented after the heating treatment. The cooling treatment is a treatment of cooling the heated coating film to about 20 to 45 °C. Thereby, the alignment of the dichroic substances contained in the coating film is further fixed, and the degree of alignment of the dichroic substances becomes further higher. As the cooling method, there is no particular limitation, and it can be implemented by a known method.

[0245] Moreover, regarding the cooling treatment carried out during the two heating treatments, from the reason of easily making the difference in the degree of alignment of the manufactured photo-absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm be 0.025 or less, it is preferably a treatment of cooling the coating film after the first heating treatment to about 30 to 45 °C.

[0246] Through the above steps, the photo-absorption anisotropic layer of the present invention can be obtained.

[0247] This manufacturing method may include a step of curing the light absorption anisotropic layer after the above-mentioned alignment step (hereinafter, also referred to as the "curing step").

[0248] Regarding the curing step, it can be carried out, for example, by heating and / or light irradiation (exposure). Among them, the curing step is preferably carried out by light irradiation.

[0249] Various light sources such as infrared rays, visible light, or ultraviolet rays can be used as the light source for curing, and ultraviolet rays are preferred. And when curing, ultraviolet rays can be irradiated while heating, or ultraviolet rays can be irradiated through a filter that only transmits a specific wavelength.

[0250] Moreover, the exposure can be carried out in a nitrogen atmosphere. When curing the light absorption anisotropic layer by radical polymerization, the polymerization hindrance caused by oxygen can be reduced, so it is preferably carried out in a nitrogen atmosphere.

[0251] The thickness of the light absorption anisotropic layer is not particularly limited, but from the viewpoint of more excellent effects of the present invention, it is preferably 0.5 to 7 μm, more preferably 1.0 to 3 μm.

[0252] 〔Liquid crystal cell〕

[0253] The liquid crystal cell included in the optical laminate of the present invention is not particularly limited as long as it is a liquid crystal cell constituting a liquid crystal panel capable of electro-optic birefringence switching.

[0254] Such a liquid crystal cell is preferably a VA (Vertical Alignment) mode, an OCB (Optically Compensated Bend) mode, an IPS (In-Plane-Switching) mode, or a TN (Twisted Nematic) mode, but is not limited to these.

[0255] In the present invention, from the reason that the viewing angle can be easily switched by turning on and off the voltage, it is preferred that the liquid crystal cell is a VA mode and can switch the in-plane retardation at a wavelength of 550 nm between 0 nm and 120 - 160 nm or between 0 nm and 250 - 300 nm.

[0256] Here, when using the above-mentioned liquid crystal cell (VA mode), it is preferred that in the first light absorption anisotropic layer and the second light absorption anisotropic layer, the light absorption anisotropic layer disposed on the visually recognizable side when used in an image display device is a specific light absorption anisotropic layer, and the other is another light absorption anisotropic layer (especially, a light absorption anisotropic layer having a transmittance central axis in the plane).

[0257] Further, in the above-described manner, from the viewpoint of switching the viewing angle to top-and-bottom light shielding (left-and-right light transmission) and omnidirectional light transmission, it is preferable that the angle formed by the in-plane slow axis of the liquid crystal layer generated when a voltage is applied to the liquid crystal cell (VA mode) and the transmission axis of the other light absorption anisotropic layer is 45°.

[0258] In the present invention, from the reason that the viewing angle can be easily switched by ON and OFF of the voltage, it is preferable that the liquid crystal cell is an IPS mode cell and the in-plane retardation at a wavelength of 550 nm is 120 to 160 nm or 250 to 300 nm.

[0259] Here, in the case of using the above-described liquid crystal cell (IPS mode), it is preferable that in the first light absorption anisotropic layer and the second light absorption anisotropic layer, the light absorption anisotropic layer disposed on the visually recognizable side when used in the image display device is a specific light absorption anisotropic layer, and the other is another light absorption anisotropic layer (particularly, a light absorption anisotropic layer having a transmittance central axis in the plane).

[0260] Further, in the above-described manner, from the viewpoint of switching the viewing angle to top-and-bottom light shielding (left-and-right light transmission) and left-and-right light shielding (top-and-bottom light transmission), it is preferable that the in-plane slow axis of the liquid crystal layer of the liquid crystal cell (IPS mode) when the voltage is ON forms an angle of 0° with the transmission axis of the other light absorption anisotropic layer, and the in-plane slow axis of the liquid crystal layer when the voltage is OFF forms an angle of 45° with the transmission axis of the other light absorption anisotropic layer.

[0261] In the present invention, from the reason that the viewing angle can be easily switched by ON and OFF of the voltage, it is preferable that the liquid crystal cell is a TN mode cell and the twist angle (torsion angle) of the orientation can be switched between 0° and 90° or between 0° and 270°.

[0262] Here, in the case of using the above-described liquid crystal cell (TN mode), it is also preferable that both the first light absorption anisotropic layer and the second light absorption anisotropic layer are specific light absorption anisotropic layers; either one of the first light absorption anisotropic layer and the second light absorption anisotropic layer, the light absorption anisotropic layer disposed on the visually recognizable side when used in the image display device is a specific light absorption anisotropic layer, and the other is another light absorption anisotropic layer (a light absorption anisotropic layer having a transmittance central axis in the plane).

[0263] In the former manner, by switching the twist angle between 0° and 90°, the viewing angle can be switched to omnidirectional light transmission and omnidirectional light shielding. In the latter manner, by switching the twist angle between 0° and 90°, the viewing angle can be switched to top-and-bottom light shielding (left-and-right light transmission) and left-and-right light shielding (top-and-bottom light transmission).

[0264] 〔Support〕

[0265] The optical laminate of the present invention may include a support.

[0266] There is no particular limitation on the type of the support, and a known support can be used. In particular, a transparent support is preferred. In addition, the transparent support refers to a support having a visible light transmittance of 60% or more, and its transmittance is preferably 80% or more, more preferably 90% or more.

[0267] Examples of the support include a glass substrate and a polymer film.

[0268] Examples of the material of the polymer film include cellulose-based polymers; acrylic-based polymers having poly(methyl methacrylate), acrylate polymers such as polymers containing lactone rings; thermoplastic norbornene-based polymers; polycarbonate-based polymers; polyester-based polymers such as polyethylene terephthalate and polyethylene naphthalate; styrene-based polymers such as polystyrene and acrylonitrile-styrene copolymers; polyolefin-based polymers such as polyethylene, polypropylene, and ethylene-propylene copolymers; vinyl chloride-based polymers; amide-based polymers such as nylon and aromatic polyamides; imide-based polymers; sulfone-based polymers; polyethersulfone-based polymers; polyetheretherketone-based polymers; polyphenylene sulfide-based polymers; vinylidene chloride-based polymers; vinyl alcohol-based polymers; vinyl butyral-based polymers; aromatic ester-based polymers; polyoxymethylene-based polymers; epoxy-based polymers; or polymers formed by mixing their polymers.

[0269] Moreover, the support is preferably a peelable support.

[0270] 〔Alignment film〕

[0271] In the optical laminate of the present invention, when the above-described light absorption anisotropic layer is a layer formed using a composition containing a liquid crystal compound, an alignment film is preferably provided as an adjacent layer.

[0272] Specific examples of the alignment film include layers of polyvinyl alcohol, polyimide, etc. with or without rubbing treatment; photo-alignment films of polyvinyl cinnamate, azo dyes, etc. with or without polarization exposure treatment.

[0273] The thickness of the alignment film is preferably 0.01 to 10 μm, more preferably 0.01 to 1 μm.

[0274] 〔Adhesive layer〕

[0275] The optical laminate of the present invention may have an adhesive layer.

[0276] The adhesive layer is preferably a transparent and optically isotropic adhesive similar to the adhesives used in ordinary image display devices, and a pressure-sensitive adhesive is usually used.

[0277] In addition to the base material (binder), conductive particles, and, if necessary, thermally expandable particles, the binder layer may be admixed with appropriate additives such as crosslinking agents (e.g., isocyanate-based crosslinking agents, epoxy-based crosslinking agents, etc.), tackifiers (e.g., rosin derivative resins, terpene resins, petroleum resins, oil-soluble phenolic resins, etc.), plasticizers, fillers, anti-aging agents, surfactants, ultraviolet absorbers, light stabilizers, antioxidants, etc.

[0278] 〔Adhesive layer〕

[0279] The optical laminate of the present invention may have an adhesive layer.

[0280] The adhesive layer exhibits adhesiveness through drying or reaction after lamination.

[0281] Polyvinyl alcohol-based adhesives (PVA-based adhesives) exhibit adhesiveness through drying, enabling bonding of materials to each other.

[0282] As specific examples of curable adhesives that exhibit adhesiveness through reaction, there may be mentioned energy ray curable adhesives or cationic polymerization curable adhesives such as (meth)acrylate-based adhesives. In addition, (meth)acrylate refers to acrylate and / or methacrylate. As curable components in (meth)acrylate-based adhesives, for example, compounds having a (meth)acryloyl group or compounds having a vinyl group may be mentioned. Also, as cationic polymerization curable adhesives, compounds having an epoxy group or an oxetanyl group can be used. The compound having an epoxy group is not particularly limited as long as it has at least 2 epoxy groups in the molecule, and various commonly known curable epoxy compounds can be used. As preferred epoxy compounds, there may be mentioned compounds having at least 2 epoxy groups and at least 1 aromatic ring in the molecule (aromatic epoxy compounds), or compounds having at least 2 epoxy groups in the molecule and at least 1 of which is formed between adjacent 2 carbon atoms constituting an alicyclic ring (alicyclic epoxy compounds), etc. as examples.

[0283] Among them, from the viewpoint of heat resistance to deformation, it is preferable to use an ultraviolet curable adhesive that is cured by ultraviolet irradiation.

[0284] 〔B plate〕

[0285] The optical laminate of the present invention may have a B plate.

[0286] As the B plate, there are a positive B plate and a negative B plate.

[0287] When the refractive index in the slow axis direction (the direction with the maximum refractive index in the plane) in the film plane is nx, the refractive index in the direction orthogonal to the slow axis in the plane is ny, and the refractive index in the thickness direction is nz, the positive B plate satisfies the relationship of formula (B1), and the negative B plate satisfies the relationship of formula (B2).

[0288] Formula (B1) nz > nx > ny

[0289] Formula (B2) nx > ny > nz

[0290] The retardation in the thickness direction of the positive B plate is negative, and the retardation in the thickness direction of the negative B plate is positive.

[0291] The in-plane retardation of the B plate at a wavelength of 550 nm is not particularly limited, but from the viewpoint of more excellent effects of the present invention, it is preferably 100 to 200 nm, and more preferably 150 to 200 nm.

[0292] The absolute value of the retardation in the thickness direction of the B plate at a wavelength of 550 nm is not particularly limited, and from the viewpoint of more excellent effects of the present invention, it is preferably 100 to 500 nm, and more preferably 120 to 400 nm.

[0293] The material constituting the B plate is not particularly limited, and it may be a layer formed of a liquid crystal compound or a resin film.

[0294] [Image display device]

[0295] The image display device of the present invention is an image display device having the above-described optical laminate of the present invention and having a viewing angle switching function, and preferably an image display device in which a specific light absorption anisotropic layer in the above-described optical laminate of the present invention is arranged to be on the visually recognizable side.

[0296] In addition, the image display device of the present invention may be a mode capable of independently switching the viewing angles of a plurality of regions within the display screen.

[0297] [Display element]

[0298] The display element used in the image display device of the present invention is not particularly limited, and examples thereof include a liquid crystal cell, an organic electroluminescence (hereinafter abbreviated as "EL") display panel, a plasma display panel, and a micro LED.

[0299] Among these, a liquid crystal cell, an organic EL display panel, or a micro LED is preferable. That is, as the display device of the present invention, a liquid crystal display device using a liquid crystal cell as a display element, an organic EL display device using an organic EL display panel as a display element, and a micro LED display device using an inorganic EL light-emitting element as a display element are preferable.

[0300] Some image display devices are thin and can be formed into a curved surface. The optically anisotropic absorption film used in the present invention is thin and easily bent, and thus can also be preferably applied to an image display device having a curved display surface.

[0301] In addition, some image display devices have a pixel density exceeding 250 ppi and can display in high definition. The optically anisotropic absorption film used in the present invention can also be preferably applied to such a high-definition image display device without generating moiré patterns.

[0302] And, as Figure 1 conceptually shown in

[0303] Examples

[0304] Hereinafter, the present invention will be further described in detail based on examples. As long as the gist of the present invention is not deviated from, the materials, amounts used, ratios, processing contents, processing steps, etc. shown in the following examples can be appropriately changed. Therefore, the scope of the present invention should not be construed restrictively by the examples shown below.

[0305] [Example 1]

[0306] [Formation of optically anisotropic layer A1]

[0307] [Formation of alignment film 1]

[0308] The surface of a cellulose acylate film (TAC substrate; manufactured by FUJIFILM Co., Ltd., TG40) with a thickness of 40 μm was saponified with an alkaline solution, and the following alignment film-forming composition 1 was coated thereon with a wire bar.

[0309] The support on which the coating film was formed was dried for 60 seconds under warm air at 60 °C, and then dried for 120 seconds under warm air at 100 °C to form alignment film 1, and a TAC film with an alignment film was obtained.

[0310] The film thickness of alignment film 1 was 1 μm.

[0311]

[0312] Modified polyvinyl alcohol PVA-1

[0313] [Chemical formula 12]

[0314]

[0315] [Formation of optically anisotropic layer A1]

[0316] The composition 1 for forming a light-absorbing anisotropic layer was continuously coated on the obtained alignment film 1 through a wire bar. After heating at 120 °C for 60 seconds, it was cooled to 35 °C. Then, it was heated at 80 °C for 60 seconds and cooled to room temperature again.

[0317] Then, using an LED lamp (center wavelength 365 nm), under the irradiation condition of an illuminance of 200 mW / cm 2 , ultraviolet rays were irradiated for 2 seconds, thereby forming a light-absorbing anisotropic layer A1 on the alignment film 1. The film thickness of the light-absorbing anisotropic layer A1 was 3.5 μm.

[0318]

[0319]

[0320] Dichroic substance D-1

[0321] [Chemical formula 13]

[0322]

[0323] Dichroic substance D-2

[0324] [Chemical formula 14]

[0325]

[0326] Dichroic substance D-3

[0327] [Chemical formula 15]

[0328]

[0329] Polymer liquid crystal compound P-1

[0330] [Chemical formula 16]

[0331]

[0332] Low-molecular liquid crystal compound M-1

[0333] [Chemical formula 17]

[0334]

[0335] Compound E-1

[0336] [Chemical formula 18]

[0337]

[0338] Compound E-2

[0339] [Chemical formula 19]

[0340]

[0341] Surfactant F-1

[0342] [Chemical formula 20]

[0343]

[0344] Regarding the fabricated light absorption anisotropic layer A1, using the above method, the angle formed between the central axis of the transmittance of the light absorption anisotropic layer and the normal direction of the surface of the light absorption anisotropic layer (hereinafter, simply referred to as "transmittance central axis angle θ") was measured, as well as the degree of orientation and its difference (ΔS) and the haze value at wavelengths of 450, 550, and 650 nm. The results are shown in Table 1 below.

[0345] [Formation of oxygen barrier layer B1]

[0346] The coating solution (oxygen barrier layer forming composition B1) having the following composition was continuously coated on the formed light absorption anisotropic layer A1 using a wire bar. Then, it was dried under warm air at 100 °C for 2 minutes, thereby forming a polyvinyl alcohol (PVA) alignment layer (oxygen barrier layer B1) with a thickness of 0.5 μm on the light absorption anisotropic layer A.

[0347] In this way, an optical film 1 was obtained that successively and adjacently included a cellulose acylate film, an alignment film 1, a light absorption anisotropic layer A1, and an oxygen barrier layer B1.

[0348]

[0349] [Fabrication of TN liquid crystal cell for viewing angle switching]

[0350] A horizontal alignment type polyimide alignment film was coated on two glass substrates with ITO electrodes, and after high-temperature drying to form the alignment film, a rubbing treatment was performed to be able to form a TN cell. Specifically, the alignment treatment was performed in such a way that it was twisted 90° up and down.

[0351] Next, a thermosetting sealing material was scattered on one of the two substrates, and a bead mill spacer (diameter 5 μm) was scattered on the other. After the two substrates were adhered, they were vacuum-packaged and heat-treated to form an empty liquid crystal cell.

[0352] Into this cell, a liquid crystal (MLC-9100 manufactured by Merck & Co., Inc.) having a positive dielectric anisotropy, a refractive index anisotropy Δn = 0.0854 (589 nm, 20 °C), and Δε = +8.5 or so was injected using a vacuum liquid crystal injector, and a TN liquid crystal cell with Δnd = 450 nm was fabricated through a sealing process.

[0353] Also, since the inner surfaces of the upper and lower substrates are subjected to rubbing treatment, when no voltage is applied, the liquid crystal layer is twisted and oriented at a twist angle of 90° between the upper and lower substrates. By applying a voltage, a TN liquid crystal cell in which the liquid crystal is oriented in the vertical direction is completed. In addition, by adjusting the diameter of the above-mentioned spacer, a liquid crystal cell with a twisted structure of arbitrary Δnd can be formed.

[0354] 〔Fabrication of optical laminate (viewing angle switching unit)〕

[0355] On both sides of the TN liquid crystal cell fabricated above, a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) was used for bonding so that the oxygen barrier layer B1 side in the above-mentioned optical film 1 became the TN liquid crystal cell side, thereby fabricating an optical laminate A1.

[0356] 〔Fabrication of image display device with viewing angle switching function〕

[0357] On the display screen of a notebook computer equipped with a liquid crystal display device, namely dynabook (manufactured by TOSHIBA Corporation), a Cosmoshine super-birefringent type (SRF, manufactured by TOYOBO CO., LTD.) (depolarization eliminating film) was bonded using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.).

[0358] Next, the above-mentioned fabricated optical laminate A1 was placed on the depolarization eliminating film, and an image display device A1 with a viewing angle switching function was fabricated.

[0359] Regarding the fabricated image display device A1, it is known that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle is switched between 0° and 90°, and along with this, the viewing angle can be switched to full-direction transmission and full-direction light shielding.

[0360] [Example 2]

[0361] 〔Fabrication of image display device A2 with viewing angle switching function〕

[0362] The composition 1 for forming the light absorption anisotropic layer was changed to the following composition 2 for forming the light absorption anisotropic layer, and an image display device A2 with a viewing angle switching function was fabricated in the same manner as in Example 1 except for this.

[0363] In addition, regarding the photoabsorptive anisotropic layer formed from the composition 2 for forming a photoabsorptive anisotropic layer, the transmittance central axis angle θ, the degree of orientation and its difference (ΔS) at wavelengths of 450, 550, and 650 nm, and the haze value were measured by the above method. The results are shown in Table 1 below.

[0364] Moreover, regarding the produced image display device A2, it was found that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle is switched between 0° and 90°, and accordingly, the viewing angle can be switched to omnidirectional transmission and omnidirectional light shielding.

[0365]

[0366]

[0367] [Example 3]

[0368] [Production of Image Display Device A3 with Viewing Angle Switching Function]

[0369] In the formation of the photoabsorptive anisotropic layer A1, the heating temperature after cooling at 35°C was changed from 80°C to 75°C. Except for this, an image display device A3 with a viewing angle switching function was produced in the same manner as in Example 1.

[0370] In addition, regarding the photoabsorptive anisotropic layer formed by changing the heating temperature, the transmittance central axis angle θ, the degree of orientation and its difference (ΔS) at wavelengths of 450, 550, and 650 nm, and the haze value were measured by the above method. The results are shown in Table 1 below.

[0371] Regarding the produced image display device A3, it was found that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle is switched between 0° and 90°, and accordingly, the viewing angle can be switched to omnidirectional transmission and omnidirectional light shielding.

[0372] [Example 4]

[0373] [Production of Polarizer]

[0374] A polarizer with a thickness of 8 μm for the polarizer and one side of the polarizer (other photoabsorptive anisotropic layer) exposed was produced by the same method as the polarizer 02 with a single-sided protective film described in International Publication No. 2015 / 166991.

[0375] [Production of Optical Laminate (Viewing Angle Switching Unit)]

[0376] On one side of the TN liquid crystal cell fabricated in Example 1, a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) was used to bond the above-fabricated polarizer so that the polarizer surface faced the TN liquid crystal side.

[0377] Next, on the side of the TN liquid crystal cell opposite to the side where the polarizer was bonded, a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) was used for bonding so that the oxygen barrier layer B1 side in the optical film 1 fabricated in Example 1 faced the TN liquid crystal cell side, thereby fabricating an optical laminate A4.

[0378] [Fabrication of an Image Display Device with a Viewing Angle Switching Function]

[0379] An image display device A4 with a viewing angle switching function was fabricated in the same manner as in Example 1, except that the optical laminate A1 was changed to the optical laminate A4. At this time, the light absorption anisotropic layer A1 (specific light absorption anisotropic layer) in the optical laminate A4 was set to be on the visually recognizable side of the image display device.

[0380] Regarding the fabricated image display device A4, it was found that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle was switched between 0° and 90°, and accordingly, the viewing angle could be switched to upper and lower light shielding (left and right transmission) and left and right light shielding (upper and lower transmission).

[0381] [Example 5]

[0382] [Fabrication of a VA Liquid Crystal Cell 1 for Viewing Angle Switching]

[0383] A liquid crystal material having negative dielectric anisotropy (MLC6608, manufactured by Merck) was dropped between glass substrates, and a liquid crystal layer was formed between the glass substrates, thereby fabricating a VA liquid crystal cell 1. The film thickness of the liquid crystal layer was adjusted so that the in-plane retardation of the liquid crystal layer (i.e., the product Δn·d of the liquid crystal layer thickness d (μm) and the refractive index anisotropy Δn) was 140 nm (λ / 4).

[0384] In addition, the liquid crystal material was oriented in a vertical orientation, and by applying a voltage, the liquid crystal was oriented in the horizontal direction, thereby completing the VN liquid crystal cell 1 that exhibited in-plane retardation.

[0385] [Fabrication of an Optical Laminate (Viewing Angle Switching Unit)]

[0386] On one side of the above-prepared VN liquid crystal cell 1, a polarizer fabricated in Example 4 was attached using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) such that the polarizer plane faced the VN liquid crystal cell side.

[0387] Next, on the side of the VN liquid crystal cell 1 opposite to the side to which the polarizer was attached, it was attached using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) such that the oxygen barrier layer B1 side in the optical film 1 fabricated in Example 1 faced the VN liquid crystal cell side, thereby fabricating an optical laminate A5. At this time, it was set such that the angle formed between the in-plane slow axis of the liquid crystal layer (horizontal alignment) generated when a voltage was applied to the VA liquid crystal cell 1 and the transmission axis of the polarizer (other light absorption anisotropic layer) was 45°.

[0388] [Fabrication of Image Display Device with Viewing Angle Switching Function]

[0389] An image display device A5 with a viewing angle switching function was fabricated in the same manner as in Example 4, except that the optical laminate A4 was changed to the optical laminate A5.

[0390] Regarding the fabricated image display device A5, it was found that by turning the voltage of the VA liquid crystal cell OFF and ON, the in-plane retardation of the liquid crystal layer switched between 0 and λ / 4, and along with this, the viewing angle could be switched to up and down light shielding (left and right transmission) and omnidirectional transmission.

[0391] [Example 6]

[0392] In the fabrication of the VA liquid crystal cell 1 for viewing angle switching in Example 5, the film thickness of the liquid crystal layer was changed such that the retardation of the liquid crystal layer, which was 140 nm, became 275 nm (λ / 2), and a VA liquid crystal cell 2 was fabricated in the same order as the VA liquid crystal cell 1, except for this change.

[0393] An image display device A6 with a viewing angle switching function was fabricated in the same manner as in Example 5, except that the VA liquid crystal cell 1 was changed to the VA liquid crystal cell 2.

[0394] Regarding the fabricated image display device A6, it was found that by turning the voltage of the VA liquid crystal cell OFF and ON, the in-plane retardation of the liquid crystal layer switched between 0 and λ / 2, and along with this, the viewing angle could be switched to up and down light shielding (left and right transmission) and left and right light shielding (up and down transmission).

[0395] [Example 7]

[0396] [Fabrication of IPS Liquid Crystal Cell for Viewing Angle Switching]

[0397] An IPS liquid crystal cell having a liquid crystal layer between two glass substrates was fabricated. When forming the liquid crystal cell, an alignment layer was formed by subjecting the glass substrates to photo-alignment treatment with reference to Example 11 of Japanese Unexamined Patent Application Publication No. 2005-351924, causing the liquid crystal compound in the liquid crystal cell to be aligned. The tilt angle of the liquid crystal compound with respect to the substrate surface was 0.1°. The Δn of the liquid crystal compound in the liquid crystal layer was 0.08625 at a wavelength of 550 nm, and Δnd was adjusted by adjusting the interval (gap; d) between the substrates. The in-plane retardation of the liquid crystal layer was 275 nm (λ / 2).

[0398] [Fabrication of Optical Laminate (Viewing Angle Switching Unit)]

[0399] On one surface of the above-fabricated IPS liquid crystal cell, a polarizing plate fabricated in Example 4 was adhered using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) such that the polarizer plane faced the IPS liquid crystal cell side.

[0400] Next, on the surface of the IPS liquid crystal cell opposite to the surface to which the polarizing plate was adhered, adhesion was performed using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) such that the oxygen barrier layer B1 side in the optical film 1 fabricated in Example 1 faced the IPS liquid crystal cell side, thereby fabricating an optical laminate A7. At this time, with respect to the liquid crystal layer in the IPS liquid crystal cell, it was set such that the angle formed by the in-plane slow axis of the liquid crystal layer when the voltage was ON and the transmission axis of the polarizer (other light absorption anisotropic layer) was 0°, and the angle formed by the in-plane slow axis of the liquid crystal layer when the voltage was OFF and the transmission axis of the polarizer (other light absorption anisotropic layer) was 45°.

[0401] [Fabrication of Image Display Device Having Viewing Angle Switching Function]

[0402] An image display device A7 having a viewing angle switching function was fabricated in the same manner as in Example 4, except that the optical laminate A4 was changed to the optical laminate A7.

[0403] Regarding the fabricated image display device A7, it was found that by turning ON and OFF the voltage of the IPS liquid crystal cell, the angle formed by the in-plane slow axis of the liquid crystal layer in the ISP liquid crystal cell and the transmission axis of the polarizer (other light absorption anisotropic layer) was switched between 0° and 45°, and accordingly, the viewing angle could be switched to upper and lower light shielding (left and right transmission) and left and right light shielding (upper and lower transmission).

[0404] [Example 8]

[0405] [Formation of Alignment Film 2]

[0406] In the same manner as in Example 1, a TAC film with an alignment film was produced. The following liquid composition E1 for forming a photo-alignment layer was further coated on the alignment layer and dried at 60°C for 2 minutes. Then, the obtained coated film was irradiated with ultraviolet rays from an oblique direction using an ultraviolet exposure apparatus (irradiation amount: 2000 mJ / cm 2 ), and an alignment film 2 (photo-alignment film) with a thickness of 0.03 μm was produced.

[0407] <Preparation of Liquid Composition E1 for Forming Photo-Alignment Layer>

[0408] The following composition was used to prepare the liquid composition F1 for forming a photo-alignment layer. It was dissolved for 1 hour while stirring and filtered through a filter with a pore size of 0.45 μm.

[0409]

[0410] Photo-alignment material E-1

[0411] [Chemical formula 21]

[0412]

[0413] 〔Formation of Photoabsorptive Anisotropic Layer A8〕

[0414] The alignment film 1 was changed to the alignment film 2, and otherwise, the photoabsorptive anisotropic layer A8 was produced in the same manner as in Example 1.

[0415] Regarding the produced photoabsorptive anisotropic layer A8, the transmittance central axis angle θ, the degree of alignment and its difference (ΔS) at wavelengths of 450, 550, and 650 nm, and the haze value were measured by the above method. The results are shown in Table 2 below.

[0416] 〔Production of Image Display Device with Viewing Angle Switching Function〕

[0417] The photoabsorptive anisotropic layer A1 was changed to the photoabsorptive anisotropic layer A8, and otherwise, an image display device A8 with a viewing angle switching function was produced in the same manner as in Example 1.

[0418] Regarding the produced image display device A8, it was found that by turning on and off the voltage of the TN liquid crystal cell, the twist angle was switched between 0° and 90°, and accordingly, the viewing angle could be switched to full-direction transmission and full-direction light shielding.

[0419] [Example 9]

[0420] 〔Production of Image Display Device A9 with Viewing Angle Switching Function〕

[0421] The composition 1 for forming a light absorption anisotropic layer was changed to the following composition 3 for forming a light absorption anisotropic layer, and an image display device A9 having a viewing angle switching function was produced in the same manner as in Example 1, except for this change.

[0422] In addition, regarding the light absorption anisotropic layer formed from the following composition 3 for forming a light absorption anisotropic layer, the transmittance central axis angle θ, the degree of orientation and its difference (ΔS) at wavelengths of 450, 550, and 650 nm, and the haze value were measured by the above method. The results are shown in Table 2 below.

[0423] Moreover, regarding the produced image display device A9, it was found that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle was switched between 0° and 90°, and along with this, the viewing angle could be switched to full-direction transmission and full-direction light shielding.

[0424]

[0425]

[0426] Dichroic substance D-4

[0427] [Chemical formula 22]

[0428]

[0429] Dichroic substance D-5

[0430] [Chemical formula 23]

[0431]

[0432] Polymer liquid crystal compound P-2

[0433] [Chemical formula 24]

[0434]

[0435] Low molecular liquid crystal compound M-2 [a mixture of 84:14:2 (mass ratio) of the following liquid crystal compounds (RA)(RB)(RC)]

[0436] [Chemical formula 25]

[0437]

[0438] [Example 10]

[0439] [Production of an image display device A10 having a viewing angle switching function]

[0440] The composition 1 for forming a light absorption anisotropic layer was changed to the following composition 4 for forming a light absorption anisotropic layer, and an image display device A10 having a viewing angle switching function was produced in the same manner as in Example 1 except for this.

[0441] In addition, regarding the light absorption anisotropic layer formed from the following composition 4 for forming a light absorption anisotropic layer, the transmittance central axis angle θ, the degree of orientation and its difference (ΔS) at wavelengths of 450, 550, and 650 nm, and the haze value were measured by the above method. The results are shown in Table 2 below.

[0442] Moreover, regarding the produced image display device A10, it was found that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle was switched between 0° and 90°, and along with this, the viewing angle could be switched to omnidirectional transmission and omnidirectional light shielding.

[0443]

[0444] Dichroic substance D-6

[0445] [Chemical formula 26]

[0446]

[0447] Low-molecular liquid crystal compound M-3

[0448] [Chemical formula 27]

[0449]

[0450] Low-molecular liquid crystal compound M-4

[0451] [Chemical formula 28]

[0452]

[0453] [Example 11]

[0454] 〔Production of image display device A11 having a viewing angle switching function〕

[0455] The composition 1 for forming a light absorption anisotropic layer was changed to the following composition 5 for forming a light absorption anisotropic layer, and an image display device A11 having a viewing angle switching function was produced in the same manner as in Example 1 except for this.

[0456] In addition, regarding the light absorption anisotropic layer formed from the following composition 5 for forming a light absorption anisotropic layer, the transmittance central axis angle θ, the degree of orientation and its difference (ΔS) at wavelengths of 450, 550, and 650 nm, and the haze value were measured by the above method. The results are shown in Table 2 below.

[0457] Further, regarding the produced image display device A11, it is known that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle is switched between 0° and 90°, and accordingly, the viewing angle can be switched to omnidirectional transmission and omnidirectional light shielding.

[0458]

[0459]

[0460] [Example 12]

[0461] [Fabrication of B Plate]

[0462] The cycloolefin resin ARTON G7810 (JSR Corporation) was dried at 100°C for 2 hours or more, and then melt-extruded at 280°C using a twin-screw kneading extruder. At this time, a screen filter, a gear pump, and a leaf disk filter were sequentially arranged between the extruder and the die, and these were connected by a melt pipe. The resin was extruded from a T-die with a width of 1000 mm and a lip gap of 1 mm, and cast onto a triple casting roll set at 180°C, 175°C, and 170°C to obtain an unstretched film 1 with a width of 900 mm and a thickness of 320 μm.

[0463] The above-mentioned unstretched film 1 during conveyance was subjected to a stretching process and a heat setting process by the following method.

[0464] (a) Longitudinal stretching

[0465] Regarding the unstretched film 1, while being conveyed using a longitudinal stretching machine between rolls with an aspect ratio (L / W) of 0.2, longitudinal stretching was performed under the following conditions.

[0466] Preheating temperature: 170°C, stretching temperature: 170°C, stretching ratio: 155%

[0467] (b) Transverse stretching

[0468] Regarding the longitudinally stretched film, while being conveyed using a tenter, transverse stretching was performed under the following conditions.

[0469] Preheating temperature: 170°C, stretching temperature: 170°C, stretching ratio: 80%

[0470] After the stretching process, the stretched film was then held at its ends by the tenter clamp, and while keeping the width of the stretched film unchanged (the range of magnification or reduction is within 3%), heat treatment was performed under the following conditions and heat setting was carried out.

[0471] Heat setting temperature: 165°C, heat setting time: 30 seconds

[0472] After heat setting, both ends were cut, and winding was performed at a tension of 25 kg / m to obtain a film roll with a width of 1340 mm and a winding length of 2000 m. The in-plane retardation at a wavelength of 550 nm of the obtained stretch film was 160 nm, the retardation in the thickness direction at a wavelength of 550 nm was 390 nm, and the film thickness was 80 μm. This was designated as Plate B.

[0473] [Production of Optical Laminate (Viewing Angle Switching Unit)]

[0474] On one surface of the IPS liquid crystal cell produced in Example 7, a polarizing plate produced in Example 4 was bonded using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) such that the polarizer surface faced the IPS liquid crystal cell side.

[0475] Next, using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.), the above-produced Plate B was bonded to the surface of the IPS liquid crystal cell on the side opposite to the surface to which the polarizing plate was bonded.

[0476] Next, bonding was performed using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Engineering Co., Ltd.) such that the oxygen barrier layer B1 side in the optical film 1 produced in Example 1 faced the Plate B side, thereby producing an optical laminate A12. At this time, with respect to the liquid crystal layer in the IPS liquid crystal cell, the angle formed by the in-plane slow axis of the liquid crystal layer when the voltage was 0N and the transmission axis of the polarizer (other light absorption anisotropic layer) was set to 0°, and the angle formed by the in-plane slow axis of the liquid crystal layer when the voltage was OFF and the transmission axis of the polarizer (other light absorption anisotropic layer) was set to 45°.

[0477] [Production of Image Display Device with Viewing Angle Switching Function]

[0478] An image display device A12 with a viewing angle switching function was produced in the same manner as in Example 4, except that the optical laminate A4 was changed to the optical laminate A12.

[0479] Regarding the produced image display device A12, it was found that by turning the voltage of the IPS liquid crystal cell ON and OFF, the angle formed by the in-plane slow axis of the liquid crystal layer in the ISP liquid crystal cell and the transmission axis of the polarizer (other light absorption anisotropic layer) was switched between 0° and 45°, and accordingly, the viewing angle could be switched to upper and lower light shielding (left and right transmission) and left and right light shielding (upper and lower transmission).

[0480] [Example 13]

[0481] [Manufacture of Image Display Device with Viewing Angle Switching Function]

[0482] On the display screen of the Galaxy S7+ (manufactured by Samsung Electronics Co., Ltd.), a tablet computer equipped with an organic EL display device, a Cosmoshine super-birefringent type (SRF, manufactured by TOYOBO CO., LTD.) (depolarization film) was adhered using a commercially available adhesive SK2057 (manufactured by Soken Chemical & Enginoering Co., Ltd.).

[0483] Next, the optical laminate A7 produced in Example 7 was placed on the depolarization film, and an image display device A13 with a viewing angle switching function was produced.

[0484] Regarding the produced image display device A13, it was found that by turning the voltage of the IPS liquid crystal cell ON and OFF, the angle formed between the in-plane slow axis of the liquid crystal layer in the ISP liquid crystal cell and the transmission axis of the polarizer (other light absorption anisotropic layer) switches between 0° and 45°. Along with this, the viewing angle can be switched to upper and lower light shielding (left and right transmission) and left and right light shielding (upper and lower transmission).

[0485] [Example 14]

[0486] [Manufacture of Image Display Device with Viewing Angle Switching Function]

[0487] On a printed circuit board, three-color light-emitting LEDs (manufactured by ROHM Co., Ltd., PICOLED, model: SMLP34RGB) were arranged in a two-dimensional lattice pattern so that the area ratio of the LEDs (light-emitting elements) became 30%. In the portion where no LEDs were arranged, a black layer made of a black matrix material for a liquid crystal display device was formed by photolithography. Thus, an EL substrate was produced (reference Figure 1 ).

[0488] Next, the optical laminate A1 produced in Example 1 was placed on the EL substrate 1, and an image display device A14 with a viewing angle switching function was produced.

[0489] Moreover, regarding the produced image display device A14, it was found that by turning the voltage of the TN liquid crystal cell ON and OFF, the twist angle switches between 0° and 90°. Along with this, the viewing angle can be switched to omnidirectional transmission and omnidirectional light shielding.

[0490] [Comparative Example 1]

[0491] [Manufacture of Image Display Device B1 with Viewing Angle Switching Function]

[0492] In Example 1, the composition 1 for forming the light absorption anisotropic layer was changed to the following composition 6 for forming the light absorption anisotropic layer, and the cooling temperature after heating at 120 °C was changed from 35 °C to 23 °C. Other than this, an image display device B1 having a viewing angle switching function was fabricated in the same manner as in Example 1.

[0493] In addition, regarding the light absorption anisotropic layer formed from the following composition 6 for forming the light absorption anisotropic layer, the transmittance central axis angle θ, the degree of orientation and its difference (ΔS) at wavelengths of 450, 550, and 650 nm, and the haze value were measured by the above method. The results are shown in Table 2 below.

[0494] Moreover, regarding the fabricated image display device B1, it was found that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle was switched between 0° and 90°, and accordingly, the viewing angle could be switched to full-direction transmission and full-direction light shielding.

[0495]

[0496]

[0497] Dichroic substance D-7

[0498] [Chemical formula 29]

[0499]

[0500] Dichroic substance D-8

[0501] [Chemical formula 30]

[0502]

[0503] Polymer liquid crystal compound P-3

[0504] [Chemical formula 31]

[0505]

[0506] Surfactant F-2

[0507] [Chemical formula 32]

[0508]

[0509] [Comparative Example 2]

[0510] [Fabrication of Image Display Device B2 with Viewing Angle Switching Function]

[0511] The light absorption anisotropic layer forming composition 6 was changed to the following light absorption anisotropic layer forming composition 7, and an image display device B2 having a viewing angle switching function was produced in the same manner as in Comparative Example 1, except for this.

[0512] In addition, regarding the light absorption anisotropic layer formed from the following light absorption anisotropic layer forming composition 7, the transmittance central axis angle θ, the degree of orientation and its difference (ΔS) at wavelengths of 450, 550, and 650 nm, and the haze value were measured by the above method. The results are shown in Table 2 below.

[0513] Moreover, regarding the produced image display device B1, it was found that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle was switched between 0° and 90°, and along with this, the viewing angle could be switched to omnidirectional transmission and omnidirectional light shielding.

[0514]

[0515] Surfactant F-3

[0516] [Chemical formula 33]

[0517]

[0518] [Comparative Example 3]

[0519] [Production of an image display device having a viewing angle switching function]

[0520] The light absorption anisotropic layer A1 was changed to the light absorption anisotropic layer produced in Comparative Example 1, and an image display device B3 having a viewing angle switching function was produced in the same manner as in Example 13, except for this.

[0521] Regarding the produced image display device B3, it was found that by turning ON and OFF the voltage of the IPS liquid crystal cell, the angle formed by the in-plane slow axis of the liquid crystal layer in the ISP liquid crystal cell and the transmission axis of the polarizer (other light absorption anisotropic layer) was switched between 0° and 45°, and along with this, the viewing angle could be switched to upper and lower light shielding (left and right transmission) and left and right light shielding (upper and lower transmission).

[0522] [Comparative Example 4]

[0523] [Production of an image display device having a viewing angle switching function]

[0524] The light absorption anisotropic layer forming composition 1 was changed to the light absorption anisotropic layer forming composition 6 used in Comparative Example 1, and the cooling temperature after heating at 120 °C was changed from 35 °C to 23 °C. An optical laminate was produced under the same conditions as in Example 1, except for this.

[0525] Next, instead of the optical laminate A1 used in the production of the image display device with a viewing angle switching function in Example 14, the above optical laminate was used, and an image display device B4 with a viewing angle switching function was produced in the same manner as in Example 14 except for this.

[0526] Moreover, regarding the produced image display device B4, it was found that by turning ON and OFF the voltage of the TN liquid crystal cell, the twist angle was switched between 0° and 90°, and along with this, the viewing angle could be switched to omnidirectional transmission and omnidirectional light shielding.

[0527] [Color of the display screen]

[0528] The color tone difference between the display screens of the image display devices (liquid crystal display devices) with a viewing angle switching function produced in Examples 1 to 12 and Comparative Examples 1 to 2 and the display screen of a dynabook (manufactured by TOSHIBA CORPORATION) with a depolarization film attached was evaluated according to the following criteria. At this time, the image display was set to full-screen white display for observation. The results are shown in Tables 1 to 3 below.

[0529] [Evaluation criteria]

[0530] A: Regarding the display screen of the dynabook with a depolarization film attached, the color tone of the display screen of the image display device with a viewing angle switching function is not a concern.

[0531] B: Regarding the display screen of the dynabook with a depolarization film attached, the color tone of the display screen of the image display device with a viewing angle switching function is slightly a concern.

[0532] C: Regarding the display screen of the dynabook with a depolarization film attached, the color tone of the display screen of the image display device with a viewing angle switching function is a concern.

[0533] [Color of the organic EL display screen]

[0534] The color tone difference between the display screens of the image display devices (organic EL display devices) with a viewing angle switching function produced in Example 13 and Comparative Example 3 and the display screen of a Galaxy S7+ (manufactured by Samsung Electronics Co., Ltd.) with a depolarization film attached was evaluated according to the following criteria. At this time, the image display was set to full-screen white display for observation. The results are shown in Table 3 below.

[0535] [Evaluation criteria]

[0536] A: Regarding the display screen of the Galaxy S7+ with a depolarization film attached, the color tone of the display screen of the image display device with a viewing angle switching function is not a concern.

[0537] B: The color tone of the display screen of the image display device with a viewing angle switching function is slightly concerning compared to the display screen of the Galaxy S7+ with a depolarizing film attached.

[0538] C: The color tone of the display screen of the image display device with a viewing angle switching function is concerning compared to the display screen of the Galaxy S7+ with a depolarizing film attached.

[0539] [Color of the micro-LED display screen]

[0540] The color tone difference of the display screens of the image display devices (micro-LED display devices) with a viewing angle switching function produced in Example 14 and Comparative Example 4 and the image display devices (micro-LED display devices) without a viewing angle switching function (in the production of the image display device with a viewing angle switching function in Example 14, the image display device without the optical laminate A1 placed) was evaluated according to the following criteria. At this time, the image display was set to full-screen white display for observation. The results are shown in Table 4 below.

[0541] [Evaluation criteria]

[0542] A: The color tone of the display screen of the image display device with a viewing angle switching function is not concerning compared to the display screen of the micro-LED display device without a viewing angle switching function.

[0543] B: The color tone of the display screen of the image display device with a viewing angle switching function is slightly concerning compared to the display screen of the micro-LED display device without a viewing angle switching function.

[0544] C: Pay attention to the color tone of the display screen of the image display device with a viewing angle switching function compared to the display screen of the micro-LED display device without a viewing angle switching function.

[0545]

[0546]

[0547] [Table 3]

[0548]

[0549] [Table 4]

[0550]

[0551] From the results shown in Tables 1 to 4, it can be seen that if the difference in the degree of orientation of the light absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm is greater than 0.025, coloration of the display screen occurs (Comparative Examples 1 to 4).

[0552] In contrast, it can be seen that when an optical laminate using at least one of the first light absorption anisotropic layer and the second light absorption anisotropic layer as a specific light absorption anisotropic layer satisfying all of the above requirements 1 to 3 is used in an image display device having a viewing angle switching function, coloration of the display screen can be suppressed (Examples 1 to 14).

[0553] In particular, from the comparison between Example 1 and Example 2, it can be seen that when the difference in the degree of orientation (ΔS) of the specific light absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm is 0.020 or less, coloration of the display screen can be further suppressed.

[0554] Furthermore, from the comparison between Example 1 and Example 8, it can be seen that when the transmittance central axis angle θ is 0° or more and less than 15°, coloration of the display screen can be further suppressed.

[0555] Symbol Explanation

[0556] 12c - EL substrate, 12R - R light emitting element, 12G - G light emitting element, 12B - B light emitting element, 24 - light emitting portion.

Claims

1. An optical laminate having, in this order, a first light absorption anisotropic layer, a liquid crystal cell, and a second light absorption anisotropic layer, at least one of the first light absorption anisotropic layer and the second light absorption anisotropic layer is a specific light absorption anisotropic layer satisfying all of the following requirements 1 to 3, Requirement 1: containing a dichroic substance, Requirement 2: the angle formed by the transmission axis center of the light absorption anisotropic layer and the normal direction of the surface of the light absorption anisotropic layer is 0° or more and 40° or less, Requirement 3: the difference in the degree of orientation of the light absorption anisotropic layer at wavelengths of 450 nm, 550 nm, and 650 nm is 0.025 or less.

2. The optical laminate according to claim 1, wherein the transmission axis center of any one of the first light absorption anisotropic layer and the second light absorption anisotropic layer exists in the in-plane direction of the light absorption anisotropic layer.

3. The optical laminate according to claim 1, wherein the haze value of the specific light absorption anisotropic layer is 0.3% or less.

4. The optical laminate according to claim 1, wherein the specific light absorption anisotropic layer contains a polymer liquid crystal compound.

5. The optical laminate according to claim 1, wherein the specific light absorption anisotropic layer contains a fluorine-based vertical alignment agent having a borate group.

6. The optical laminate according to claim 1, wherein the liquid crystal cell is a VA mode and can switch the in-plane phase difference at a wavelength of 550 nm between 0 nm and 120 - 160 nm, or between 0 nm and 250 - 300 nm.

7. The optical laminate according to claim 1, wherein the liquid crystal cell is an IPS mode and the in-plane phase difference at a wavelength of 550 nm is 120 - 160 nm or 250 - 300 nm.

8. The optical laminate according to claim 1, wherein the liquid crystal cell is a TN mode and can switch the twisted angle of orientation between 0° and 90°, or between 0° and 270°.

9. An image display device having a viewing angle switching function, wherein the image display device has the optical laminate according to any one of claims 1 to 8.

10. The image display device according to claim 9, wherein, The image display device can independently switch the viewing angles of multiple regions within the display screen.

Images