Optically anisotropic material and optical filter

Abstract

To provide an optically anisotropic material which offers superior wide view angle characteristics in the visible light range.SOLUTION: An optically anisotropic material is provided, comprising an optically anisotropic film containing a liquid crystal compound with reverse wavelength dispersion characteristics and a near-infrared absorbing dye, and a positive C-plate.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an optically anisotropic material, an optical filter, and the like. [Background technology]

[0002] Optically anisotropic films with refractive index anisotropy are used in a variety of applications, including optical filters for display devices. Examples of such optical filters include λ / 4 retardation plates used in organic electroluminescence (EL) display devices and optical compensation filters for liquid crystal display devices. Optical compensation filters compensate for optical shifts (phase differences) when light from a backlight passes through a liquid crystal layer, thereby expanding the viewing angle of the display device. This can improve color shifts when viewed from an oblique angle and light leakage during black display.

[0003] Here, Patent Document 1 describes an optical filter that includes a positive A plate and a positive C plate and exhibits reverse wavelength dispersion. Furthermore, Patent Document 2 describes an optical filter in which two retardation films are bonded together. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6243869 [Patent Document 2] Patent No. 5876440 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the techniques described in Patent Documents 1 and 2 do not provide a sufficiently wide viewing angle characteristic in the visible light region.

[0006] An object of the present invention is to provide an optically anisotropic material that has excellent wide viewing angle characteristics in the visible light region. [Means for solving the problem]

[0007] The present invention relates to the following optically anisotropic material, etc. [1] An optically anisotropic body comprising an optically anisotropic film containing a liquid crystal compound exhibiting reverse wavelength dispersion and a near-infrared absorbing dye, and a positive C plate. [2] When the optical anisotropy axis in the horizontal direction is set to 0°, the directions of 0°, 45°, 90°, and 135° are set as the rotation axes, respectively. From angles of -50° to 50° (in 10° increments) relative to each of the rotation axes, When linearly polarized light is incident at an angle of 45° to the optical anisotropy axis at normal incidence, An optically anisotropic substance having an average ellipticity of 0.90 or more in the wavelength range of 450 to 650 nm. [Effects of the Invention]

[0008] According to the present invention, an optically anisotropic material having excellent wide viewing angle characteristics in the visible light region can be provided. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing an optically anisotropic material according to one embodiment of the present invention. [Figure 2] FIG. 2 is a graph showing the ellipticity of the optically anisotropic film 1-1 mainly in the wavelength region of visible light. [Figure 3] FIG. 3 is a graph showing the ellipticity of the optically anisotropic film 1-2 mainly in the wavelength region of visible light. [Figure 4] FIG. 4 is a graph showing the ellipticity of the optically anisotropic film 1-3 mainly in the wavelength region of visible light. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention (hereinafter also referred to as the present embodiment) will be described. In this specification, a compound represented by formula (A1) is also referred to as compound (A1), and the same applies to compounds represented by other formulas. A dye comprising compound (A1) is also referred to as dye (A1), and the same applies to compounds represented by other formulas. Furthermore, for example, a group represented by formula (1a) is also referred to as group (1a), and the same applies to groups represented by other formulas. In this specification, the use of "to" to indicate a range of values includes the upper and lower limits.

[0011] In this specification, unless otherwise specified, the alkyl group may be linear, branched, cyclic, or a combination of these structures. Unless otherwise specified, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc., with a fluorine atom being preferred. In this specification, unless otherwise specified, an aryl group refers to a group that bonds via a carbon atom constituting an aromatic ring of an aromatic compound, such as a benzene ring, a naphthalene ring, a biphenyl ring, etc. Furthermore, a heteroaryl group refers to a group that bonds via a carbon atom or a heteroatom constituting an aromatic ring of an aromatic compound having a heteroatom, such as a furan ring, a thiophene ring, a pyrrole ring, etc.

[0012] In this specification, a squarylium compound refers to a compound having a squarylium skeleton represented by the following formula (S1) that can have a resonance structure represented by the following formula (S2) in its structural formula. In this specification, the squarylium skeleton is represented by either formula (S1) or formula (S2).

[0013] [ka]

[0014] In this specification, the ellipticity can be measured using an ellipticity measuring device (for example, RETS-100 manufactured by Otsuka Electronics Co., Ltd.). Alternatively, the ellipticity may be calculated from the retardation measured using a retardation measurement device (e.g., RETS-100 manufactured by Otsuka Electronics) using the following formulas (1) and (2), where θ is the ellipticity angle, Re is the in-plane retardation, and λ is the wavelength. Ellipticity X=tanθ (1) sin2θ=sin(Re / λ×360°) (2) The ellipticity is preferably measured using an ellipticity measuring device.

[0015] In this specification, the spectral characteristics can be measured using a spectrophotometer. Unless otherwise specified, the measurement direction refers to the characteristics at an incident angle of 0°.

[0016] In this specification, retardation means retardation in the thickness direction for a positive C-plate, and means in-plane retardation for others.

[0017] <Optical anisotropy> 1, an optically anisotropic body 1 according to this embodiment comprises an optically anisotropic film 2 containing a liquid crystal compound exhibiting reverse wavelength dispersion and a near-infrared absorbing dye, and a positive C plate 3. With this configuration, the front ellipticity and oblique incidence ellipticity in the visible light region are equal to or greater than a specific value, and an optically anisotropic body with excellent wide viewing angle characteristics is obtained. Here, ellipticity correlates with retardation (phase difference). When an optically anisotropic material is used as a quarter-wave plate, linearly polarized light is converted into perfectly circularly polarized light at Re=λ / 4 (ellipticity=1), resulting in ideal optical properties. In other words, the closer the front ellipticity and oblique incidence ellipticity are to 1 in the visible light range, the more the retardation (phase difference) follows the ideal line λ / 4 in that range, resulting in an optically anisotropic material that can improve color shifts when viewed from an oblique angle and light leakage during black display.

[0018] (optically anisotropic film) The optically anisotropic film in this embodiment preferably has an ellipticity of 0.90 or more over the entire wavelength range of 430 to 680 nm when measured with linearly polarized light incident from the perpendicular direction. When the ellipticity is above the above range over the entire wavelength range of 430 to 680 nm, which is visible light, the retardation (phase difference) follows the ideal line λ / 4 over a wide band of visible light in that range, and an optically anisotropic film with excellent wide viewing angle characteristics is obtained, which is preferable. The ellipticity of the optically anisotropic film is more preferably 0.92 or more. In order for the optically anisotropic film to satisfy the above ellipticity, for example, the optically anisotropic film may contain a specific near-infrared absorbing dye, which will be described later.

[0019] The optically anisotropic film in this embodiment preferably exhibits reverse wavelength dispersion, which means that when the in-plane retardation (Re) value of the optically anisotropic film is measured at a specific wavelength (visible light range), the Re value becomes equal to or higher as the measured wavelength increases. For example, the optically anisotropic film may exhibit reverse wavelength dispersion if it contains a reverse wavelength dispersion liquid crystal compound.

[0020] (near infrared absorbing dye) The optically anisotropic film in this embodiment preferably contains a near-infrared absorbing dye, particularly a near-infrared absorbing dye having a specific structure as described below, which can increase the ellipticity of the optically anisotropic film in the visible light region. The near-infrared absorbing dye is preferably a dye having dichroism in the near-infrared region. The term "dichroic" means that the absorbance in the long axis direction of the dye is different from the absorbance in the short axis direction. Furthermore, it is more preferable that the absorbance in the short axis direction is greater than the absorbance in the long axis direction in the near-infrared region. This can further increase the ellipticity of the optically anisotropic film in the visible light region.

[0021] In general, in the wavelength region away from the characteristic absorption wavelength, the refractive index of an organic dye decreases monotonically with increasing wavelength. This phenomenon is called normal dispersion. In contrast, in the wavelength region including the characteristic absorption wavelength, the refractive index changes rapidly with increasing wavelength, which is called anomalous dispersion. Specifically, the refractive index decreases rapidly on the short wavelength side of the characteristic absorption wavelength and increases rapidly on the long wavelength side of the characteristic absorption wavelength. As described above, when an optically anisotropic film is used as a quarter-wave plate, linearly polarized light is converted into perfectly circularly polarized light at Re=λ / 4, resulting in ideal optical characteristics. In near-infrared absorbing dyes, the refractive index in the minor axis direction drops sharply just before the intrinsic absorption wavelength, so the refractive index difference increases on the long wavelength side of the visible light region. Since the in-plane retardation of an optically anisotropic film is calculated from the product of the refractive index difference and the film thickness, if the film thickness is constant, the retardation increases as the refractive index difference increases, and it can approach λ / 4 over the entire visible light wavelength range of 430 to 680 nm.

[0022] The absorbance in the long axis direction of the near-infrared absorbing dye is measured from the absorption spectrum obtained by irradiating the optically anisotropic film with polarized light parallel to the orientation direction of the near-infrared absorbing dye, and the absorbance in the short axis direction is measured from the absorption spectrum obtained by irradiating the optically anisotropic film with polarized light perpendicular to the orientation direction of the near-infrared absorbing dye.

[0023] The near-infrared absorbing dye preferably has a dichroic ratio of 1.5 or more, more preferably 2.0 or more. The larger the dichroic ratio, the more likely the retardation increases in the long wavelength region, and the more likely it is to approach λ / 4 over the entire visible wavelength range of 430 to 680 nm, resulting in an optically anisotropic film with high ellipticity in that region. Furthermore, since a near-infrared absorbing dye with a dichroic ratio of 1.5 or more can achieve the retardation-increasing effect even in small amounts, there is no need to increase its content in the optically anisotropic film, and it is possible to maintain high transmittance for visible light and near-infrared light around the sensing wavelength.

[0024] The near-infrared absorbing dye preferably has a maximum absorption wavelength in dichloromethane at a wavelength of 650 to 900 nm. By having the maximum absorption wavelength in this range, the retardation in the long wavelength region increases and tends to approach λ / 4 over the entire wavelength region of 430 to 680 nm of visible light, thereby making it possible to obtain an optically anisotropic film with high ellipticity in this region.

[0025] The near-infrared absorbing dye preferably has a squarylium skeleton, since the dye has low absorption in the visible light region and can therefore suppress coloration of the resulting optically anisotropic film.

[0026] The near-infrared absorbing dye preferably has a mesogen group. A mesogen group is a functional group that is rigid and has orientation properties. The mesogen group preferably has a structure containing two or more cyclic structures such as aromatic rings or alicyclic rings, and more preferably has a structure in which such cyclic structures are linked directly or via a linking group. When the near-infrared absorbing dye has a mesogen group, the dye is easily oriented in the optically anisotropic film, making it easy to control the desired optical properties.

[0027] Examples of the near-infrared absorbing dye include a compound represented by the following formula (3) or a compound represented by the formula (4) described below. R L -DR L (3) In formula (3), D is a divalent group having a squarylium skeleton, and R L is a monovalent mesogenic group. Two R L may be the same or different. In the case of the near-infrared absorbing dye (3) described above, two mesogenic groups are symmetrically bonded around the squarylium skeleton, which makes it easier for the dye to be aligned with the liquid crystal compound.

[0028] Mesogenic group R L is preferably represented by the following formula (2). R L '-Sp1-〔Cy-Sp2〕 n -Sp3- (2) In equation (2), RL ' is a hydrogen atom, an electron-withdrawing monovalent organic group, or a polymerizable monovalent organic group. Examples of the electron-withdrawing monovalent organic group include CN, CF3, and F. Examples of the polymerizable monovalent organic group include polymerizable groups that can undergo radical polymerization or cationic polymerization. As the radical polymerizable group, known radical polymerizable groups can be used, and an acryloyl group or a methacryloyl group is preferred. As the cationically polymerizable group, known cationically polymerizable groups can be used, and specific examples thereof include an alicyclic ether group, a cyclic acetal group, a cyclic lactone group, a cyclic thioether group, a spiro orthoester group, and a vinyloxy group. Among these, an alicyclic ether group or a vinyloxy group is preferred, and an epoxy group, an oxetanyl group, or a vinyloxy group is more preferred.

[0029] The terminal R of the mesogenic group L The structure of "" can be selected depending on the purpose of the optically anisotropic film to be obtained. For example, in the case of a voltage-driven liquid crystal, a monovalent organic group having electron-withdrawing properties is preferred, and in the case of a liquid crystal having a polymerizable group, a monovalent organic group having polymerizability is preferred, and a hydrogen atom is preferred regardless of the purpose.

[0030] In formula (2), Cy is an arylene group which may have a substituent, a heteroarylene group which may have a substituent, or a cycloalkylene group which may have a substituent. Examples of the arylene group include a phenylene group, a naphthalene group, and a tetrahydronaphthalene group. Examples of the heteroarylene group include a furan ring, a pyrrole ring, a thiophene ring, a pyridine ring, a thiazole ring, and a benzothiazole ring. Examples of the cycloalkylene group include a cyclohexylene group, a cyclohexelene group, a decahydronaphthalene group, and a dioxane group. Substituents in Cy include a methyl group and a methoxy group.

[0031] In formula (2), Sp1, Sp2, and Sp3 each independently represent one group or bond selected from a single bond, an alkylene group, an alkenylene group, an alkynylene group, a carbonyl group, an ester bond, an amide bond, and an ether bond, or a combination thereof. The alkylene group is preferably a linear alkylene group having 1 to 12 carbon atoms.

[0032] n is an integer of 2 to 9, and preferably an integer of 2 to 6. In addition, in formula (2), two or more [Cy-Sp2] structures may be the same or different.

[0033] The mesogenic group represented by formula (2) preferably includes structures represented by the following formulae (2-2) to (2-4), and in particular, structures represented by formulae (2-2) and (2-4) are more preferred.

[0034] [ka]

[0035] The near-infrared absorbing dye (3) is more preferably at least one selected from the group consisting of a compound represented by the following formula (3-1A), a compound represented by the following formula (3-1B), and a compound represented by the following formula (3-2). In the following compounds (3-1A) to (3-2), mesogenic groups are arranged so as to extend in a direction perpendicular to the squarylium skeleton at the center of the compound, and therefore the squarylium skeleton is likely to be aligned in a direction perpendicular to the slow axis of the optically anisotropic film to be formed. In other words, absorption in the infrared region (particularly wavelengths of 700 to 900 nm) originating from the squarylium skeleton is likely to be obtained in a direction perpendicular to the slow axis of the optically anisotropic film, and an optically anisotropic film exhibiting desired properties is likely to be obtained.

[0036] [ka]

[0037] [ka]

[0038] In formula (3-1A), formula (3-1B), and formula (3-2), R L is R in the above formula (2) L The definitions and preferred embodiments are the same as those of the above.

[0039] In formula (3-1A), X 1 is a carbon atom or nitrogen atom which may have a monovalent substituent. From the viewpoint of improving red transmittance, a carbon atom is preferred, and from the viewpoint of improving blue transmittance, a nitrogen atom is preferred. Examples of the monovalent substituent on the carbon atom include a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkynyl group having 1 to 9 carbon atoms, an aromatic ring which may have a substituent, a hydroxyl group, a carboxy group, a sulfo group, a cyano group, an amino group, an N-substituted amino group, a nitro group, an alkoxycarbonyl group, a carbamoyl group, an N-substituted carbamoyl group, an imido group, and an alkoxy group having 1 to 19 carbon atoms.

[0040] In formula (3-1A), Y 1 is an oxygen atom, a sulfur atom, or an NH group. 1 When is one of these elements or groups, Y 1 The five-membered ring containing the group becomes aromatic, improving blue light transmittance. From the viewpoint of improving red light transmittance, a sulfur atom is preferred, and from the viewpoints of improving red light transmittance and making absorption steeper by hydrogen bonding, an NH group is preferred.

[0041] In formula (3-1B), X 2 is a sulfur atom or an oxygen atom. From the viewpoint of improving red light transmittance, a sulfur atom is preferred. In formula (3-1B), Y 2is a carbon atom or nitrogen atom which may have a monovalent substituent. From the viewpoint of improving blue light transmittance, a nitrogen atom is preferred. Examples of the monovalent substituent on a carbon atom include a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbon atoms, a hydroxyl group, a carboxy group, a sulfo group, a cyano group, an amino group, an N-substituted amino group, a nitro group, an alkoxycarbonyl group, a carbamoyl group, an N-substituted carbamoyl group, an imido group, and an alkoxy group having 1 to 19 carbon atoms.

[0042] In formula (3-1A) and formula (3-1B), R 11 , R 12 are each independently an alkyl group having 1 to 20 carbon atoms, which may have a substituent and which may contain an unsaturated bond between carbon atoms, an oxygen atom, an alicyclic ring, or an aromatic ring. The alkyl group may be linear or branched, with linear being preferred from the viewpoint of orientation, and branched being preferred from the viewpoint of solubility.

[0043] As the alkyl group having 1 to 20 carbon atoms, if it is linear, it is preferably a linear alkyl group having 1 to 15 carbon atoms, and more preferably a linear alkyl group having 1 to 10 carbon atoms. If it is branched, it is preferably a branched alkyl group having 3 to 15 carbon atoms, and more preferably a branched alkyl group having 3 to 8 carbon atoms.

[0044] Also, R 11 , R 12 It is more preferable that at least one of R is a branched alkyl group having 3 to 15 carbon atoms, 11 , R 12 It is particularly preferred that both of the groups are branched alkyl groups having 3 to 8 carbon atoms. R 11 , R 12 may be the same or different, but are preferably the same from the viewpoint of symmetry.

[0045] In addition, R 11 , R 12 When R has a substituent, the number of carbon atoms of the substituent is 11 , R 12The number of carbon atoms is included in the number of carbon atoms. Examples of the substituent include a halogen atom, a hydroxyl group, a carboxy group, a sulfo group, a cyano group, an amino group, an N-substituted amino group, a nitro group, an alkoxycarbonyl group, a carbamoyl group, an N-substituted carbamoyl group, an imido group, and an alkoxy group having 1 to 19 carbon atoms.

[0046] In formula (3-1A) and formula (3-1B), R 13 , R 14 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. From the viewpoint of orientation, a hydrogen atom is preferred.

[0047] In formula (3-1A) and formula (3-1B), R 11 and R 12 , R 11 and R 13 , R 12 and R 13 , R 13 and R 14 may be bonded to each other to form a ring, which preferably has 4 to 6 members.

[0048] More specifically, the compound represented by formula (3-1A) includes the compounds shown in the following table. In compound (3-1A), X 1 is a nitrogen atom, and Y 1 is an NH group, the compound is (3-1Ai), and X 1 is a carbon atom, and Y 1 is an NH group, the compound is designated as compound (3-1Aii). In the compounds shown in the table below, the symbols on the left and right of the squarylium skeleton have the same meaning. Also, R L is as defined above.

[0049] [Table 1]

[0050] [Table 2]

[0051] More specifically, the compound represented by formula (3-1B) includes the compounds shown in the following table. In compound (3-1B), X 2 is a sulfur atom, it is called compound (3-1Bi), and X 2 is an oxygen atom, the compound is designated as compound (3-1Bii). In the compounds shown in the table below, the symbols on the left and right of the squarylium skeleton have the same meaning. Also, R L is as defined above.

[0052] [Table 3]

[0053] [Table 4]

[0054] In formula (3-2), R 21 , R 22 are each independently an alkyl group having 1 to 20 carbon atoms, which may have a substituent and which may contain an unsaturated bond between carbon atoms, an oxygen atom, an alicyclic ring, or an aromatic ring. The alkyl group may be linear or branched, with linear being preferred from the viewpoint of orientation, and branched being preferred from the viewpoint of solubility.

[0055] As the alkyl group having 1 to 20 carbon atoms, if it is linear, it is preferably a linear alkyl group having 1 to 15 carbon atoms, and more preferably a linear alkyl group having 1 to 10 carbon atoms. If it is branched, it is preferably a branched alkyl group having 3 to 15 carbon atoms, and more preferably a branched alkyl group having 3 to 8 carbon atoms.

[0056] Also, R 21 , R 22 It is more preferable that at least one of R is a branched alkyl group having 3 to 15 carbon atoms, 21 , R 22 It is particularly preferred that both of the groups are branched alkyl groups having 3 to 8 carbon atoms. R 21 , R 22 may be the same or different, but are preferably the same from the viewpoint of symmetry.

[0057] In addition, R 21 , R 22 When R has a substituent, the number of carbon atoms of the substituent is 21 , R 22 The number of carbon atoms is included in the number of carbon atoms. Examples of the substituent include a halogen atom, a hydroxyl group, a carboxy group, a sulfo group, a cyano group, an amino group, an N-substituted amino group, a nitro group, an alkoxycarbonyl group, a carbamoyl group, an N-substituted carbamoyl group, an imido group, and an alkoxy group having 1 to 19 carbon atoms.

[0058] In formula (3-2), R 23 is a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. From the viewpoint of orientation, a hydrogen atom is preferred.

[0059] In formula (3-2), R 21 and R 22 , R 21 and R 23 , R 22 and R 23 may be bonded to each other to form a ring, which preferably has 4 to 6 members.

[0060] More specifically, compounds represented by formula (3-2) include the compounds shown in the following table: In the compounds shown in the following table, the symbols on the left and right of the squarylium skeleton have the same meaning. Also, R L is as defined above.

[0061] [Table 5]

[0062] The near-infrared absorbing dye (3) can be produced, for example, by the synthesis method shown below.

[0063] The synthesis method of the near-infrared absorbing dye (3-1Ai) is shown below. The starting material is commercially available. L CHO can be synthesized according to known methods, for example, as described in paragraph

[0131] of JP-A-2011-207782.

[0064] [ka]

[0065] The synthesis method of the near-infrared absorbing dye (3-1Aii) is shown below. The starting material is commercially available. L Br can be synthesized according to known methods, for example, as described in Synlett, 2009, 20, 3279-3282.

[0066] [ka]

[0067] The synthesis methods for the near-infrared absorbing dyes (3-1Bi) and (3-1Bii) are shown below. The starting materials are commercially available. L COCl can be synthesized according to a known method, for example, as described in paragraph

[0093] of JP-A-2014-58490.

[0068] [ka]

[0069] [ka]

[0070] The synthesis method of the near-infrared absorbing dye (3-2) is shown below. The starting material can be synthesized according to a known method, for example, as described in WO 2021 / 112020. L BPin can be synthesized according to known methods, for example, as described in Org. Biomol. Chem., 2016, 14, 9974-9980.

[0071] [ka]

[0072] The near-infrared absorbing dye (4) is a compound represented by the following formula (4).

[0073] [ka]

[0074] In equation (4), R 41 and R 42 each independently represents a hydrogen atom or a substituent, at least one of which is an electron-withdrawing group, and R 41 and R 42 may be bonded to form a ring. 43 each independently represents a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a substituted boron group, or a metal atom; R 41 R L each independently represents a mesogenic group.

[0075] The near-infrared absorbing dye (4) exhibits low absorption in the visible light region, thereby further suppressing coloration of the resulting optically anisotropic film. Furthermore, since this compound contains a mesogenic group, it is easily aligned with the liquid crystal compound. Since the mesogenic group is arranged so as to extend laterally from the fused ring moiety containing the nitrogen atom at the center of the compound, the fused ring moiety is easily aligned in a direction perpendicular to the slow axis of the resulting optically anisotropic film. In other words, absorption in the infrared region (particularly wavelengths of 700 to 900 nm) originating from the fused ring moiety is easily obtained in a direction perpendicular to the slow axis of the optically anisotropic film, making it easy to obtain an optically anisotropic film exhibiting the desired properties.

[0076] R 41 and R 42 each independently represents a hydrogen atom or a substituent, at least one of which is an electron-withdrawing group, and R 41 and R42 may be bonded to form a ring. Examples of the substituent include an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, an aromatic heterocyclic oxy group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfonylamino group, a sulfamoyl group, a carbamoyl group, an alkylthio group, an arylthio group, an aromatic heterocyclic thio group, a sulfonyl group, a sulfinyl group, a ureido group, a phosphoric acid amide group, a hydroxy group, a mercapto group, a halogen atom, a cyano group, a sulfo group, a carboxyl group, a nitro group, a hydroxamic acid group, a sulfino group, a hydrazino group, an imino group, a heterocyclic group, and a silyl group.

[0077] Examples of the electron-withdrawing group include a cyano group, an acyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, a sulfamoyl group, a sulfinyl group, and a heterocyclic group.

[0078] R 41 and R 42 When they are bonded to form a ring, they form a 5- to 7-membered ring (preferably a 5- or 6-membered ring), and the ring formed is preferably one that is normally used as an acidic nucleus in a merocyanine dye. R 41 and R 42 The ring formed by bonding is preferably a 1,3-dicarbonyl nucleus, a pyrazolinone nucleus, a 2,4,6-triketohexahydropyrimidine nucleus (including thioketones), a 2-thio-2,4-thiazolidinedione nucleus, a 2-thio-2,4-oxazolidinedione nucleus, a 2-thio-2,5-thiazolidinedione nucleus, a 2,4-thiazolidinedione nucleus, a 2,4-imidazolidinedione nucleus, a 2-thio-2,4-imidazolidinedione nucleus, a 2-imidazolin-5-one nucleus, a 3,5-pyrazolidinedione nucleus, a benzothiophen-3-one nucleus, or an indanone nucleus.

[0079] R 41is preferably a heterocyclic group. The heterocyclic group is preferably a pyrazole ring group, a thiazole ring group, an oxazole ring group, an imidazole ring group, an oxadiazole ring group, a thiadiazole ring group, a triazole ring group, a pyridine ring group, a pyridazine ring group, a pyrimidine ring group, a pyrazine ring group, a benzo-fused ring group or a naphtho-fused ring group thereof, or a complex of these fused rings.

[0080] R 43 each independently represents a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a substituted boron group, or a metal atom; R 41 may be covalently or coordinately bonded to R 43 The substituent of the substituted boron represented by R 41 and R 42 has the same meaning as the substituents described above, and is preferably an alkyl group, an aryl group, or a heteroaryl group. R 43 The metal atom represented by the formula (I) is preferably a transition metal atom, a magnesium atom, an aluminum atom, a calcium atom, a barium atom, a zinc atom, or a tin atom, and more preferably an aluminum atom, a zinc atom, a tin atom, a vanadium atom, an iron atom, a cobalt atom, a nickel atom, a copper atom, a palladium atom, an iridium atom, or a platinum atom.

[0081] R L each independently represents a mesogenic group. The definition of the mesogenic group is the same as that of the group represented by formula (2).

[0082] The compound represented by formula (4) can be synthesized, for example, based on the method described in Chemistry A European Journal, 2009, Vol. 15, pp. 4857-4864.

[0083] As the near-infrared absorbing dye, near-infrared absorbing dye (3) is particularly preferred because it has a high molar absorption coefficient and exhibits absorption properties even in small amounts. Because it exhibits absorption properties even in small amounts, sufficient optical properties can be obtained, for example, even with a small amount added to an optically anisotropic film. The molar absorption coefficient of near-infrared absorbing dye (3) at the maximum absorption wavelength in dichloromethane is preferably 200,000 L / (mol cm) or more, more preferably 250,000 L / (mol cm) or more.

[0084] The optically anisotropic film in this embodiment may contain only one type of near-infrared absorbing dye, or may contain a combination of multiple types of near-infrared absorbing dyes. The content of the near-infrared absorbing dye in the optically anisotropic film is preferably 0.1 to 15% by mass, more preferably 0.5 to 10% by mass, and particularly preferably 1 to 8% by mass. From the viewpoint of improving ellipticity, it is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and particularly preferably 1% by mass or more. From the viewpoint of visible light transmittance, it is preferably 15% by mass or less, more preferably 10% by mass or less, and particularly preferably 8% by mass or less.

[0085] (liquid crystal compound) The optically anisotropic film in this embodiment contains a liquid crystal compound exhibiting reverse wavelength dispersion, together with the near-infrared absorbing dye. By including a liquid crystal compound, the near-infrared absorbing dye can be easily aligned in the film, and therefore an optically anisotropic film with controlled optical properties can be obtained, which is preferable. Furthermore, a liquid crystal compound exhibiting reverse wavelength dispersion (hereinafter also referred to as a reverse wavelength dispersion liquid crystal compound) means a compound in which an optically anisotropic film produced using the compound exhibits reverse wavelength dispersion. In other words, a reverse wavelength dispersion liquid crystal compound means a liquid crystal compound in which, when the in-plane retardation (Re) value of an optically anisotropic film produced using only the compound is measured at a specific wavelength (visible light range), the Re value becomes equal or increases as the measured wavelength increases. A liquid crystal compound exhibiting reverse wavelength dispersion is preferable in that retardation is improved on the short wavelength side.

[0086] From the viewpoint of visible light transmittance, the liquid crystal compound is preferably a liquid crystal compound that transmits visible light. The types of liquid crystal compounds include non-polymerizable liquid crystal compounds exhibiting a nematic phase, polymerizable liquid crystal compounds exhibiting a nematic phase, polymerizable liquid crystal compounds exhibiting a smectic phase, etc. From the viewpoint of alignment, non-polymerizable liquid crystal compounds exhibiting a nematic phase and polymerizable liquid crystal compounds exhibiting a nematic phase are preferred.

[0087] As a liquid crystal compound exhibiting reverse wavelength dispersion, a known compound can be used, for example, the liquid crystal compounds shown below and the liquid crystal compounds described in JP-A-2011-207765 and WO 2021 / 039625 can be used.

[0088] [ka]

[0089] The optically anisotropic film in this embodiment may contain a plurality of liquid crystal compounds. When a plurality of liquid crystal compounds is used, the film may contain a plurality of reverse wavelength dispersion liquid crystal compounds, or may contain a flat wavelength dispersion liquid crystal compound in addition to the reverse wavelength dispersion liquid crystal compound. When the liquid crystal compounds contain a reverse wavelength dispersion liquid crystal compound and a flat wavelength dispersion liquid crystal compound, the optically anisotropic film preferably exhibits reverse wavelength dispersion. By mixing a flat wavelength dispersion liquid crystal compound, the reverse wavelength dispersion can be adjusted.

[0090] A flat-dispersion liquid crystal compound means a compound that, when used solely as a liquid crystal compound, causes an optically anisotropic film to exhibit flat dispersion. In other words, a flat-dispersion liquid crystal compound means a liquid crystal compound that, when the in-plane retardation (Re) value of an optically anisotropic film produced solely from the compound is measured at a specific wavelength (visible light range), exhibits almost no change in the in-plane retardation value from the short wavelength side to the long wavelength side.

[0091] The content of the liquid crystal compound in the optically anisotropic film in this embodiment is preferably 50 to 99.9% by mass, more preferably 80 to 99.5% by mass, and particularly preferably 90 to 99% by mass. From the viewpoint of expressing a stable liquid crystal phase over a wide temperature range, it is preferably 50% by mass or more, more preferably 80% by mass or more, and particularly preferably 90% by mass or more. From the viewpoint of achieving sufficient absorbance, it is preferably 99.9% by mass or less, more preferably 99.5% by mass or less, and particularly preferably 99% by mass or less.

[0092] The optically anisotropic film in this embodiment may contain other components in addition to the near-infrared absorbing dye and liquid crystal compound described above. For example, when the liquid crystal compound is a polymerizable liquid crystal compound, the liquid crystal compound may contain, as other components, a polymer of a polymerizable monomer. The polymerizable monomer may be a radically polymerizable or cationic polymerizable compound. Among them, a polyfunctional radically polymerizable monomer is preferred. Furthermore, the polymerizable monomer is preferably a monomer copolymerizable with the polymerizable liquid crystal compound. The content of the polymerizable monomer in the optically anisotropic film is preferably from 1 to 50% by mass, more preferably from 2 to 30% by mass, based on the total mass of the liquid crystal compound.

[0093] The optically anisotropic film may contain other components, such as a surfactant. The surfactant may be a conventionally known compound.

[0094] The optically anisotropic film may contain other components such as antioxidants, such as Irganox 1010 (manufactured by BASF).

[0095] The optically anisotropic film may contain, as other components, various alignment control agents such as a vertical alignment agent and a horizontal alignment agent. These alignment control agents are compounds that can control the alignment of liquid crystal compounds on the interface side to be horizontal or vertical.

[0096] The thickness of the optically anisotropic film in this embodiment is preferably 0.5 to 4.0 μm, more preferably 1.5 to 3.0 μm, from the viewpoint of retardation.

[0097] (Positive C Plate) The optically anisotropic body according to this embodiment includes the optically anisotropic film and a positive C plate, which can further improve visibility in oblique directions. A positive C plate is a retardation film that adjusts the vertical retardation by aligning the liquid crystal compound in a homeotropic manner, i.e., by aligning the molecular long axes of the liquid crystal compound in a vertical direction. The positive C plate preferably exhibits a smectic phase or a nematic phase, and more preferably exhibits a smectic phase. The smectic phase is preferred because it forms a highly ordered layer structure in which the centers of gravity of the liquid crystal compounds are aligned, making it easier to achieve homeotropic alignment.

[0098] From the viewpoint of manufacturability and physical properties, the film thickness of the positive C plate is preferably 1.0 to 5.5 μm, more preferably 2.0 to 5.0 μm, and even more preferably 3.0 to 4.5 μm.

[0099] The retardation (Rth) in the thickness direction of the positive C plate is preferably from −300 to 0, more preferably from −200 to −20, and even more preferably from −120 to −40, from the viewpoint of improving the viewing angle characteristics.

[0100] (Other layers) The optically anisotropic body according to this embodiment may have, as another layer, for example, an adhesive layer between the optically anisotropic film and the positive C plate. The positive C plate may be formed directly on the optically anisotropic film, but when a separately manufactured positive C plate is attached to the optically anisotropic film, it is preferable to attach them via an adhesive layer from the viewpoint of improving adhesion. An optical adhesive film or the like can be used as the adhesive layer.

[0101] (Properties of optically anisotropic materials) The optically anisotropic body according to this embodiment has high average ellipticity in both the front direction and the oblique incidence direction in the visible light region, thereby providing an optically anisotropic body with excellent wide viewing angle characteristics in the visible light region.

[0102] The average ellipticity in the front direction in the visible light region is the average ellipticity at normal incidence measured using a retardation measuring device, and is preferably 0.90 or more, more preferably 0.92 or more, from the viewpoint of wide viewing angle characteristics in the visible light region.

[0103] The average ellipticity in the oblique incidence direction in the visible light region is measured by the following method, and is preferably 0.90 or more, more preferably 0.91 or more, from the viewpoint of wide viewing angle characteristics in the visible light region. When the optical anisotropy axis in the horizontal direction is set to 0°, the rotation axes are set to 0°, 45°, 90°, and 135°, respectively, and linearly polarized light is incident from angles of -50° to 50° (in 10° increments) to each rotation axis at an angle of 45° to the optical anisotropy axis at normal incidence. The average ellipticity is measured in the wavelength range of 450 to 650 nm. A retardation measurement device is used for the measurement.

[0104] <Method for producing optically anisotropic body> (Formation of optically anisotropic film) The optically anisotropic film can be produced, for example, by curing a composition containing the near-infrared absorbing dye, liquid crystal compound, other components, and any optional components required for production.

[0105] Optional components necessary during production include a solvent and, when the liquid crystal compound is a polymerizable liquid crystal compound, a polymerization initiator. The polymerization initiator is selected depending on the type of polymerization reaction, and examples thereof include thermal polymerization initiators and photopolymerization initiators. Examples of photopolymerization initiators include α-carbonyl compounds, acyloin ethers, α-hydrocarbon-substituted aromatic acyloin compounds, polynuclear quinone compounds, and combinations of triarylimidazole dimers and p-aminophenyl ketones. The content of the polymerization initiator in the composition is preferably from 0.01 to 20% by mass, more preferably from 0.5 to 10% by mass, based on the total solid content of the composition. The solvent is preferably an organic solvent. Examples of the organic solvent include amides, sulfoxides, heterocyclic compounds, hydrocarbons, alkyl halides, esters, ketones, and ethers. Two or more organic solvents may be used in combination.

[0106] The method for curing the composition is not particularly limited, and any known method can be used. In the optically anisotropic film, the near-infrared absorbing dye is preferably aligned.

[0107] Since the optically anisotropic film in this embodiment contains a liquid crystal compound, the near-infrared absorbing dye can be aligned by aligning the liquid crystal compound. For example, a composition containing a near-infrared absorbing dye and a liquid crystal compound (hereinafter also referred to as a "liquid crystal composition") is applied to form a coating film, and the coating film is then subjected to an alignment treatment to align the liquid crystal compound. Furthermore, if the liquid crystal compound is a polymerizable liquid crystal compound, the resulting coating film can be cured (by irradiation with light or by heating) to form an optically anisotropic film.

[0108] The procedure for forming an optically anisotropic film by aligning a polymerizable liquid crystal compound will be described in detail below.

[0109] First, a liquid crystal composition is applied onto a support to form a coating film, and the coating film is subjected to an alignment treatment to align the polymerizable liquid crystal compound.

[0110] The support used is a member that functions as a base material for applying the composition, and may be a temporary support that is peeled off after the liquid crystal composition is applied and cured. The support (temporary support) may be a plastic film or a glass substrate. The thickness of the support is preferably 5 to 1000 μm, more preferably 10 to 300 μm, and particularly preferably 15 to 90 μm.

[0111] If necessary, an alignment layer may be disposed on the support. The alignment layer is generally composed mainly of a polymer. Polymers for alignment layers are described in many publications and many commercially available products are available. Preferred polymers for alignment layers are polyvinyl alcohol, polyimide, or derivatives thereof. The alignment layer is preferably subjected to a known rubbing treatment, photo-alignment treatment, or groove alignment treatment. The thickness of the alignment layer is preferably 0.01 to 10 μm, more preferably 0.01 to 1 μm.

[0112] Examples of the method for applying the liquid crystal composition include curtain coating, dip coating, spin coating, print coating, spray coating, slot coating, roll coating, slide coating, blade coating, gravure coating, and wire bar coating. In any case, single-layer application is preferred.

[0113] The coating film formed on the support is subjected to an alignment treatment to align the polymerizable liquid crystal compound in the coating film. The alignment treatment can be carried out by drying the coating film at room temperature or by heating the coating film. In the case of a thermotropic liquid crystal compound, the liquid crystal phase formed by the alignment treatment can generally be transitioned by a change in temperature or pressure. In the case of a lyotropic liquid crystal compound, the transition can also be achieved by changing the composition ratio, such as the amount of solvent.

[0114] The conditions for heating the coating are not particularly limited, but the heating temperature is preferably 50 to 250° C., more preferably 50 to 150° C., and the heating time is preferably 10 seconds to 10 minutes. After heating the coating film, the coating film may be cooled, if necessary, before the curing treatment (light irradiation treatment) described below. The cooling temperature is preferably 20 to 200°C, and more preferably 20 to 150°C. The difference between the heating temperature of the coating film and the cooling temperature of the coating film is not particularly limited, and is preferably 40 to 150°C. In particular, when the coating film is heated and cooled before being subjected to a curing treatment, it is preferable that the heating temperature TA of the coating film is 50 to 250°C and the cooling temperature TB is in the range of the heating temperature TA x 0.1 to the heating temperature TA x 0.7.

[0115] Next, the coating film in which the polymerizable liquid crystal compound is aligned is subjected to a curing treatment. The method of curing the coating film in which the polymerizable liquid crystal compound is oriented is not particularly limited, and examples thereof include light irradiation treatment and heat treatment. Among these, from the viewpoint of manufacturability, light irradiation treatment is preferred, and ultraviolet irradiation treatment is more preferred. The irradiation conditions for the light irradiation treatment are not particularly limited, but are preferably 50 to 3000 mJ / cm 2 The irradiation dose is preferably 1000 ppm or more.

[0116] In the above-mentioned production method, by adjusting various conditions, it is possible to adjust the arrangement of the near-infrared absorbing dye, and as a result, it is possible to adjust the optical properties of the optically anisotropic film. For example, by adjusting the heating temperature when orienting the polymerizable liquid crystal compound after applying the liquid crystal composition to a support to form a coating film, and the cooling temperature when cooling after heating, it is possible to adjust the arrangement state of the near-infrared absorbing dye, and as a result, the optical properties of the optically anisotropic film.

[0117] (Positive C-plate formation) The positive C plate can be produced by a known method. For example, it may be formed by applying a composition for a positive C plate containing a liquid crystal compound and the like onto an optically anisotropic film and curing the applied composition, or by laminating a commercially available positive C plate onto the optically anisotropic film via an adhesive layer.

[0118] <Applications of optically anisotropic materials> The optically anisotropic body according to this embodiment can be used in various applications. For example, by adjusting the in-plane retardation of the optically anisotropic body, it can be used as a so-called phase difference plate, preferably as a λ / 4 plate. A λ / 4 plate is a plate that has the function of converting linearly polarized light of a specific wavelength into circularly polarized light (or circularly polarized light into linearly polarized light). More specifically, it is a phase difference plate whose in-plane retardation Re at a specific wavelength λnm is ¼ wavelength (or an odd multiple thereof).

[0119] The optically anisotropic material according to this embodiment is suitable as an optical filter in a display device. For example, the optical filter according to this embodiment is suitable for use as an optical compensation filter for optically compensating a liquid crystal cell in a liquid crystal display device, and can improve color shift when viewed from an oblique direction and light leakage during black display.

[0120] A further preferred embodiment of the optical filter according to this embodiment is a circular polarizer comprising the optically anisotropic material according to this embodiment and a polarizer. This circular polarizer is useful as an anti-reflection film in an organic electroluminescence display device, and can further suppress reflected color.

[0121] The polarizer may be any member (linear polarizer) that has the function of converting light into a specific linearly polarized light, and an absorptive polarizer can be mainly used. Examples of absorption-type polarizers include iodine-based polarizers, dye-based polarizers using dichroic dyes, polyene-based polarizers, etc. Iodine-based polarizers and dye-based polarizers include coated polarizers and stretched polarizers, and either can be used, but polarizers produced by adsorbing iodine or a dichroic dye to polyvinyl alcohol and stretching the resulting material are preferred. The relationship between the absorption axis of the polarizer and the slow axis of the optical anisotropic material is not particularly limited, but when the optical anisotropic material is a λ / 4 plate and the optical filter is used as a circular polarizing filter, the angle between the absorption axis of the polarizer and the slow axis of the optical anisotropic material is preferably 45°±10°.

[0122] The optically anisotropic material according to this embodiment may be used in a polarization folding optical system (a so-called pancake optical system) for VR or MR. The polarization folding optical system corresponds to a conventional optical lens portion. The polarization folding optical system is an optical system that utilizes the reflection of polarized light to obtain a longer optical path length than conventional systems by combining components such as a λ / 4 plate, a half mirror, and a reflective polarizer instead of conventional lenses. The polarization folding optical system can reduce the distance between the lens and the display of a VR or MR headset, thereby enabling weight reduction. The optically anisotropic material according to this embodiment can preferably be used as a λ / 4 plate. Use of the optically anisotropic material according to this embodiment is expected to improve the color reproducibility of VR or MR.

[0123] As described above, this specification discloses the following optically anisotropic body, optical filter, and image display device. [1] An optically anisotropic body comprising an optically anisotropic film containing a liquid crystal compound exhibiting reverse wavelength dispersion and a near-infrared absorbing dye, and a positive C plate. [2] When the optical anisotropy axis in the horizontal direction is set to 0°, the directions of 0°, 45°, 90°, and 135° are set as the rotation axes, respectively. From angles of -50° to 50° (in 10° increments) relative to each of the rotation axes, When linearly polarized light is incident at an angle of 45° to the optical anisotropy axis at normal incidence, An optically anisotropic substance having an average ellipticity of 0.90 or more in the wavelength range of 450 to 650 nm. [3] The optically anisotropic body according to [1], wherein the ellipticity of the optically anisotropic film is 0.90 or more over the entire wavelength range of 430 to 680 nm when measured with linearly polarized light incident from a perpendicular direction. [4] The optically anisotropic substance according to [1] or [3], wherein the near-infrared absorbing dye is a compound represented by the following formula (4):

[0124] [ka]

[0125] [In formula (4), R 41and R 42 each independently represents a hydrogen atom or a substituent, at least one of which is an electron-withdrawing group, and R 41 and R 42 may be bonded to form a ring. 43 each independently represents a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a substituted boron group, or a metal atom; R 41 R L each independently represents a mesogenic group. [5] The optical anisotropic substance according to [1], [3] or [4], wherein the near-infrared absorbing dye is at least one selected from the group consisting of a compound represented by the following formula (3-1A), a compound represented by the following formula (3-1B), and a compound represented by the following formula (3-2):

[0126] [ka]

[0127] [ka]

[0128] [In formula (3-1A), formula (3-1B), and formula (3-2), R L are each independently a mesogenic group. In formula (3-1A), X 1 Y each independently represents a carbon atom or a nitrogen atom which may have a monovalent substituent. 1 is an oxygen atom, a sulfur atom, or an NH group. In formula (3-1B), X 2 are each independently a sulfur atom or an oxygen atom. 2 are each independently a carbon atom or a nitrogen atom which may have a monovalent substituent. In formula (3-1A) and formula (3-1B), R 11 , R 12R are each independently an alkyl group having 1 to 20 carbon atoms, which may have a substituent and which may contain an unsaturated bond between carbon atoms, an oxygen atom, an alicyclic ring, or an aromatic ring. 13 , R 14 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. In formula (3-2), R 21 , R 22 R are each independently an alkyl group having 1 to 20 carbon atoms, which may have a substituent and which may contain an unsaturated bond between carbon atoms, an oxygen atom, an alicyclic ring, or an aromatic ring. 23 are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. [6] The optically anisotropic body according to any one of [1] and [3] to [5], which has an adhesive layer between the optically anisotropic film and the positive C plate. [7] An optical filter comprising the optically anisotropic body according to any one of [1] to [6]. [8] An image display device comprising the optically anisotropic body according to any one of [1] to [6]. [Example]

[0129] Next, the present invention will be explained more specifically with reference to examples. A retardation measurement device (RETS-100, manufactured by Otsuka Electronics) was used to measure the retardation and ellipticity. A visible absorption spectrometer (SolidSpec-3700DUV, manufactured by Shimadzu Corporation) was used to measure the reflection spectrum and spectral characteristics.

[0130] [Synthesis Example 1: Synthesis of Dye A-1]

[0131] [ka]

[0132] <Synthesis of compound (a1)> A 50 mL two-necked flask was charged with 17 mL of THF and 4.61 g (13.5 mmol) of (methoxymethyl)triphenylphosphonium chloride. Under a nitrogen atmosphere and ice cooling, 1.52 g (13.4 mmol) of potassium t-butoxide was slowly added and stirred for 30 minutes. 1.50 g (6.66 mmol) of 4-(trans-4-propylcyclohexyl)cyclohexanone was slowly added and stirred for 30 minutes. The mixture was then returned to room temperature and stirred for 1.5 hours. After completion of the reaction, 10 mL of water and 10 mL of brine were added, extracted three times with ethyl acetate, dried over sodium sulfate, and the solvent was removed under reduced pressure. The resulting solid was suspended in hexane, filtered to remove the solid, and the solvent was removed under reduced pressure to obtain the crude compound. The resulting compound was placed in a 50 mL two-necked recovery flask, and under a nitrogen atmosphere and ice cooling, THF (17 mL), hydrochloric acid (2.1 mL), and water (2.1 mL) were added. The mixture was returned to room temperature and stirred for 1 hour. After the reaction was complete, 20 mL of brine was added, and the mixture was extracted three times with ethyl acetate. After drying with sodium sulfate, the solvent was removed under reduced pressure to obtain the crude compound. After removing the solvent, the mixture was purified by column chromatography using hexane:dichloromethane = 2:1 to obtain 0.807 g of compound (a1). (Yield 51%)

[0133] <Synthesis of compound (a2)> 10.0 g (73.4 mmol) of 2,1,3-benzothiadiazole was added to a 300 mL round-bottom flask. Under ice cooling, 200 g (2039 mmol) of concentrated sulfuric acid was added, and the mixture was allowed to cool to room temperature and stirred for 1 hour until dissolved. Then, 12.4 g (69.8 mmol) of N-bromosuccinimide was added again under ice cooling, and the mixture was allowed to cool to room temperature and stirred for 1 hour until dissolved. After stirring for another hour to complete the reaction, the reaction solution was added dropwise to 800 mL of ice water. A solid precipitated, which was then allowed to stand and the solution removed by decantation. An additional 800 mL of water was added, and the solution was allowed to stand and decanted. The precipitated solid was then filtered to obtain crude compound (a2). This compound was suspended in 100 mL of a hexane / ethyl acetate (1:1, volume ratio) solution and heated to 60 °C to dissolve the solid. The solution was allowed to cool to room temperature and the precipitated solid was removed by filtration. The solid removed was the dibromo compound. The filtrate was washed with 100 mL of saturated aqueous sodium bicarbonate solution and dried over anhydrous sodium sulfate, after which the solvent was removed under reduced pressure to obtain 9.15 g of a solid. The obtained solid was compound (a2):dibromo compound = 1:0.17 (molar ratio), and the amount of compound (a2) contained was 7.42 g (yield 47%).

[0134] <Synthesis of compound (a3)> A 500 mL three-necked round-bottom flask equipped with a reflux condenser was charged with 0.63 g (0.93 mmol) of PEPPSI™-IPr, 9.15 g (Br equivalent: 46.3 mmol) of the compound (a2) obtained above (containing 17.0 mol% of the dibromo form), 6.75 g (60.2 mmol) of potassium t-butoxide, and 200 mL of toluene. After degassing and nitrogen substitution, 9.57 mL (55.5 mmol) of diisobutylamine was added and the mixture was stirred at 100 °C for 5 hours. After completion of the reaction, solids were removed from the reaction mixture by filtration through Celite, and the filtrate was concentrated to obtain crude compound (a3). This was purified by column chromatography using hexane / ethyl acetate (24:1, volume ratio) as a developing solvent to obtain 8.53 g of compound (a3) (yield: 94%).

[0135] <Synthesis of compound (a4)> A 50 mL two-necked flask was charged with 0.834 g (3.16 mmol) of compound (a3) and 13 mL of ethanol. Under a nitrogen atmosphere and ice cooling, 0.37 g (9.70 mmol) of sodium borohydride and 0.253 g (1.06 mmol) of cobalt(II) chloride hexahydrate dissolved in ethanol were slowly added and stirred for 2 hours. After completion of the reaction, the mixture was filtered through Celite with dichloromethane, and 10 mL of saturated aqueous ammonium chloride and 20 mL of saturated aqueous sodium bicarbonate were added. The mixture was extracted five times with dichloromethane, dried over sodium sulfate, and the solvent was removed under reduced pressure to obtain crude compound (a4). Compound (a4) was used unpurified in the next reaction.

[0136] <Synthesis of compound (a5)> A 50 mL two-necked flask equipped with a reflux condenser was charged with 0.744 g (3.16 mmol) of the compound (a4) obtained above and 17 mL of DMA. Under a nitrogen atmosphere, 0.354 g (3.41 mmol) of sodium bisulfite was added and the mixture was heated to 100 °C. 0.856 g (3.62 mmol) of compound (a1) dissolved in DMA was slowly added dropwise over 15 minutes, and the mixture was stirred at 100 °C for 3 hours. After the reaction was complete, 50 mL of saturated aqueous sodium hydroxide was added, and the mixture was extracted three times with hexane:ethyl acetate = 4:1, washed with water, dried over sodium sulfate, and the solvent was removed under reduced pressure to obtain the crude compound. This was then purified using a column with hexane:ethyl acetate = 4:1 to obtain 0.94 g of compound (a5) (61% yield).

[0137] <Synthesis of dye A-1> 0.94 g (2.1 mmol) of compound (a5), 40 mL of 1-butanol, and 40 mL of toluene were added to a 300 mL three-necked round-bottom flask. 0.167 g (1.42 mmol) of squaric acid was added under a nitrogen atmosphere and refluxed for 3 hours. After the reaction was completed, the solvent was removed under reduced pressure, and the residue was suspended in hexane and filtered to obtain crude dye A-1. This was purified using a column with hexane:ethyl acetate:chloroform = 2:1:10 to obtain dye A-1 (yield 86%). 1H-NMR(400MHz,CHLOROFORM-D)δ12.94(s,1H),7.95(dd,J=15.5,9.1Hz,2H),6.44(dd,J=9.2,2.3Hz,2H),3.88(d,J=6.4Hz,8H),2.87-2.76(m,2H),2.36-2 .26(m,4H),2.19-2.11(m,4H),1.91-1.89(m,4H),1.79-1.75(m,8H),1.67-1. 61(m,4H),1.35-1.14(m,26H),0.96(d,J=6.6Hz,24H),0.88(t,J=7.3Hz,6H).

[0138] [Synthesis Example 2: Synthesis of Dye A-2]

[0139] [ka]

[0140] Dye A-2 was synthesized in the same manner as dye A-1, except that diisobutylamine used in the synthesis of compound (a3) was changed to di(2-ethylhexyl)amine. 1 H-NMR(400MHz,CHLOROFORM-D)δ12.97(s,2H),7.95(d,J=9.0Hz,2H),6.49(d,J=9.0H z,2H),4.08(s,8H),2.86-2.78(m,2H),2.28(d,J=11.7Hz,4H),1.92-0.86(m,108H).

[0141] [Synthesis Example 3: Synthesis of Dye A-3]

[0142] [ka]

[0143] Dye A-3 was synthesized in the same manner as dye A-1, except that in the synthesis of dye A-1, compound (a1) was changed to compound (a1′) represented by the following formula (a1′).

[0144] [ka]

[0145] 1 H-NMR(400MHz,CHLOROFORM-D)δ13.10(s,2H),7.99(d,J=9.1Hz,2H),7.25(d,J=8.3Hz,4H),7.01(d,J=8.3Hz ,4H),6.52(d,J=9.1Hz,2H),4.20-3.79(m,8H),2.97(t,J=11.6Hz,2H),2.67(t,J=11.3Hz,2H),2.46-2.40(m, H),2.19-0.84(m,122H).

[0146] [Synthesis Example 4: Synthesis of Dye B-1]

[0147] [ka]

[0148] <Synthesis of compound (b1)> A 50 mL two-necked eggplant flask was charged with 1.44 g (5.71 mmol) of trans-4-(trans-4-propylcyclohexyl)cyclohexanecarboxylic acid, 0.734 g (6.01 mmol) of 4-dimethylaminopyridine, 27.3 mL of dichloromethane, and 1.16 g (6.05 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and stirred for 20 minutes under a nitrogen atmosphere. 1.20 g (5.46 mmol) of 4-iodophenol was added and stirred for 2 hours. After the reaction was complete, 10 mL of 1 M hydrochloric acid and 10 mL of water were added. The mixture was extracted five times with dichloromethane, washed with saturated aqueous sodium bicarbonate, dried over sodium sulfate, and the solvent was removed under reduced pressure to obtain crude compound (b1). This was purified by column chromatography using a 1:1 hexane:dichloromethane mixture to obtain 2.19 g of compound (b1) (88% yield).

[0149] <Synthesis of compound (b2)> A 50 mL two-necked eggplant flask was charged with 1.06 g (7.66 mmol) of 3-nitroaniline and 15 mL of DMF. Under a nitrogen atmosphere, 1.43 g (8.03 mmol) of N-bromosuccinimide was added and stirred for 1 hour. After the reaction was complete, 20 mL of saturated aqueous sodium bicarbonate and 20 mL of water were added, and the mixture was extracted three times with hexane:ethyl acetate = 4:1, washed with water, dried over sodium sulfate, and the solvent was removed under reduced pressure to obtain crude compound (b2). This was then purified using a column with hexane:ethyl acetate = 1:1 to obtain 1.56 g of compound (b2) (yield 94%).

[0150] <Synthesis of compound (b3)> A 100 mL two-necked recovery flask was charged with 1.56 g (7.18 mmol) of compound (b2), 14 mL of acetic acid, and 14 mL of acetonitrile. Under a nitrogen atmosphere and ice cooling, 0.816 g (21.6 mmol) of sodium borohydride was added and stirred for 20 minutes. 2.0 mL (21.5 mmol) of isobutyraldehyde was added, and the mixture was returned to room temperature and stirred for 5 hours. After the reaction was complete, 10 mL of water was added and the solvent was removed under reduced pressure. The mixture was neutralized with aqueous sodium hydroxide, extracted three times with ethyl acetate, dried over sodium sulfate, and the solvent was removed under reduced pressure to obtain crude compound (b3). This was purified using a column chromatography column with hexane:ethyl acetate = 93:7 to obtain 2.19 g of compound (b3) (yield 93%).

[0151] <Synthesis of compound (b4)> 2.19 g (6.65 mmol) of compound (b3) and 22 mL of THF were added to a 100 mL two-necked recovery flask, and 14 mL of vinyl magnesium chloride (1.6 mol / L, THF solution) was slowly added at -40°C under a nitrogen atmosphere and stirred for 4 hours. After the reaction was completed, 15 mL of saturated aqueous ammonium chloride solution was added, and the mixture was extracted three times with ethyl acetate. After drying with sodium sulfate, the solvent was removed under reduced pressure to obtain crude compound (b4). Compound (b4) was used in the next reaction as is.

[0152] <Synthesis of compound (b5)> 2.15 g (6.65 mmol) of the compound (b4) obtained above, 44 mL of ethyl acetate, and 4.6 mL (33 mmol) of triethylamine were added to a 200 mL recovery flask, and 0.53 g of Pd / C was added under a nitrogen atmosphere. The mixture was then substituted with hydrogen and stirred for 15 hours. After the reaction was complete, the mixture was filtered through Celite and the solvent was removed under reduced pressure to obtain crude compound (b5). This was then purified using a column with hexane:ethyl acetate = 10:1 to obtain 0.524 g of compound (b5) (yield 32%).

[0153] <Synthesis of compound (b6)> A 50 mL two-necked flask was charged with 0.524 g (2.14 mmol) of compound (b5), 0.409 g (4.34 mmol) of 2-norbornene, 0.593 g (4.29 mmol) of potassium carbonate, 0.056 g (0.214 mmol) of bis(acetonitrile)palladium(II) dichloride, 10.7 mL of DMA, and 0.1 mL of water. The mixture was degassed, and 1.94 g (4.26 mmol) of compound (b1) was added under a nitrogen atmosphere and stirred at 70 °C for 24 hours. After the reaction was complete, 30 mL of water was added, and the mixture was extracted three times with dichloromethane, washed with brine, dried over sodium sulfate, and then filtered through Celite. The filtrate was recovered and the solvent was removed under reduced pressure. The resulting solid was washed with hexane, and the residue was recovered to give crude compound (b6). This was purified by column chromatography using hexane:dichloromethane=1:3 to obtain 0.403 g of compound (b6) (yield 33%).

[0154] <Synthesis of dye B-1> Dye B-1 was synthesized in the same manner as dye A-1, except that compound (a5) in the synthesis of dye A-1 was changed to compound (b6). 1H-NMR(400MHz,CHLOROFORM-D)δ13.37(d,J=102.0Hz,2H),8.11(d,J=8.8Hz,2H),7.8 1(t,J=9.1Hz,4H),7.22-7.15(m,4H),6.79(s,2H),6.47(s,2H),3.61(s,8H),2.54-2. 45(m,2H),2.29-2.17(m,8H),1.91-1.86(m,4H),1.79-1.72(m,8H),1.61-1.52(m,4H ),1.34-1.25(m,4H),1.17-1.05(m,18H),0.99(d,J=6.7Hz,24H),0.90-0.83(m,12H).

[0155] [Synthesis Example 5: Synthesis of Dye C-1]

[0156] [ka]

[0157] <Synthesis of compound (c1)> Compound (c1) was synthesized in the same manner as compound (b1), except that 4-iodophenol was replaced with 4-bromophenol.

[0158] <Synthesis of compound (c2)> A 50 mL two-necked flask was charged with 0.684 g (1.68 mmol) of compound (c1), 8.6 mL of 1,4-dioxane, 0.450 g (5.06 mmol) of potassium acetate, and 0.0743 g (0.0901 mmol) of [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane adduct. The mixture was degassed, and 0.501 g (1.87 mmol) of bis(pinacolato)diboron was added under a nitrogen atmosphere and stirred at 80 °C for 6 hours. After completion of the reaction, 6 mL of saturated aqueous sodium bicarbonate and 10 mL of water were added. The mixture was extracted three times with ethyl acetate, dried over sodium sulfate, and the solvent was removed under reduced pressure to obtain the crude compound. This was then purified using a column chromatography column with hexane:ethyl acetate = 10:1 to obtain 0.632 g of compound (c2) (83% yield).

[0159] <Synthesis of compound (c3)> Compound (c3) was synthesized based on the method described in paragraphs

[0264] to

[0267] of International Publication No. 2021 / 112020.

[0160] <Synthesis of compound (c4)> A 50 mL two-necked flask was charged with 5.3 mL of 1,4-dioxane, 0.489 g (1.07 mmol) of compound (c3), 0.056 g (0.212 mmol) of triphenylphosphine, and 0.605 g (1.33 mmol) of compound (c2). 0.585 g (4.23 mmol) of potassium carbonate dissolved in 0.9 mL of water was then added. After degassing, 0.046 g (0.055 mmol) of [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane adduct was added under a nitrogen atmosphere and stirred at 100 °C for 24 hours. After completion of the reaction, 10 mL of water was added, and the mixture was extracted three times with ethyl acetate. The mixture was dried over sodium sulfate and then filtered through Celite. The solvent in the filtrate was removed under reduced pressure to obtain crude compound (c4). This was purified by column chromatography using hexane:ethyl acetate=20:1 to obtain 0.529 g of compound (c4) (yield 70%).

[0161] <Synthesis of dye C-1> A 100 mL two-necked recovery flask was charged with 0.529 g (0.749 mmol) of compound (c4), 30 mL of 1-propanol, 10 mL of toluene, and 0.82 mL (7.5 mmol) of trimethyl orthoformate. Under a nitrogen atmosphere, 0.062 g (0.54 mmol) of squaric acid was added and the mixture was stirred at 80°C for 1.5 hours. After the reaction was completed, the solvent was removed under reduced pressure to obtain crude dye C-1. This was purified using a column with hexane:ethyl acetate:dichloromethane=10:1:5, yielding 0.214 g of dye C-1 (38% yield). 1H-NMR(400MHz,CHLOROFORM-D)δ7.60(dd,J=6.7,1.9Hz,4H),7.22(dd,J=6.7, 1.9Hz,4H),6.04(s,2H),3.32-3.21(m,8H),2.48(tt,J=12.2,3.6Hz,2H),2.1 9(d,J=11.0Hz,4H),1.88(d,J=9.1Hz,8H),1.79-1.73(m,8H),1.55(t,J=12.0 Hz, 4H), 1.40-1.21 (m, 40H), 1.17-0.96 (m, 16H), 0.89 (td, J=7.3, 3.3Hz, 32H).

[0162] [Synthesis Example 6: Synthesis of Dye D-1]

[0163] [ka]

[0164] Dye D-1 was synthesized according to the above scheme with reference to Chemistry A European Journal, 2009, Vol. 15, pp. 4857-4864.

[0165] [Optical anisotropic film 1-1] The following materials were mixed in the ratios shown in Table 6 below, dissolved in dichloromethane, and dried to remove the dichloromethane, thereby obtaining polymerizable liquid crystal composition 1-1. Liquid crystal compound L-1 was synthesized based on the method described in JP 2011-207765 A. Liquid crystal compound L-1 is a polymerizable liquid crystal compound that exhibits reverse wavelength dispersion and a nematic phase. Irganox 1010 manufactured by BASF was used as the antioxidant. As the photopolymerization initiator, Irgacure 369E manufactured by BASF was used.

[0166] [ka]

[0167] [Table 6]

[0168] An alignment cell manufactured by EHC Corporation with a gap of 2.3 μm was heated to 160° C., and the obtained polymerizable liquid crystal composition 1-1 was poured into the cell and allowed to cool to 120° C. to form a nematic phase. UV light with a wavelength of 365 nm was applied at 80 mW / cm at 120°C. 2 The polymerizable liquid crystal composition 1-1 was polymerized by irradiating the light for 60 seconds at 1000 W for 60 seconds, thereby obtaining an optically anisotropic film 1-1. Using a retardation measurement device, the in-plane retardation in the visible light region (430 to 680 nm) at normal incidence was measured, and the ellipticity (X) was calculated using the following equations (1) and (2), where θ is the ellipticity angle, Re is the retardation, and λ is the wavelength. X=tanθ (1) sin2θ=sin(Re / λ×360°) (2)

[0169] [Optical anisotropic films 1-2 to 1-4] Polymerizable liquid crystal compositions 1-2 to 1-4 were prepared according to the same procedure as for polymerizable liquid crystal composition 1-1, except that the dye and dye concentration were changed to the conditions shown in Table 7 below. Polymers were obtained to produce optically anisotropic films 1-2 to 1-4, and the retardation in the vertical direction in the visible light region (430 to 680 nm) was measured, and the ellipticity was calculated.

[0170] The ellipticities calculated from the retardations of the optically anisotropic films 1-1 to 1-4 are summarized in Table 7 below. 2 to 4 show the correlation between wavelength and ellipticity in the optically anisotropic films 1-1 to 1-3, respectively. Regarding ellipticity, if it was 0.90 or more in the entire wavelength range of 430 to 680 nm, it was rated as A, and if it was less than 0.90 in some range, it was rated as B.

[0171] [Table 7]

[0172] From the above results, it was found that by adding various near-infrared absorbing dyes to a reverse wavelength dispersion liquid crystal compound, optically anisotropic films 1-1 to 1-3 having an ellipticity of 0.9 or more over the entire visible light range (430 to 680 nm) could be prepared.

[0173] [Example 2-1] A positive C plate was attached to the optically anisotropic film 1-1 to produce an optically anisotropic body X-1. Optical adhesive films were used to attach each layer. NVFILM manufactured by ENEOS Liquid Crystal Corporation was used as the positive C plate. The Rth of the positive C plate was -99.0 nm and the film thickness was 4.4 μm.

[0174] The optically anisotropic material X-1 was evaluated for front ellipticity in the visible light region (450 to 650 nm), oblique incidence ellipticity, and viewing angle characteristics using an antireflector. Details of each evaluation method are shown below.

[0175] <Front ovality evaluation> Using a retardation measurement device, the ellipticity at normal incidence in the visible light region (450 to 650 nm) was measured, and when the average value was 0.90 or more, it was rated as A, and when it was less than 0.90, it was rated as B.

[0176] <Evaluation of oblique incidence ellipticity> When the optical anisotropy axis in the horizontal direction is set to 0°, the rotation axes are set to 0°, 45°, 90°, and 135°, respectively. Linearly polarized light is incident from angles of -50° to 50° (in 10° increments) relative to each rotation axis, at an angle of 45° relative to the optical anisotropy axis at normal incidence, and the average ellipticity in the visible light range (450 to 650 nm) is calculated.

[0177] <Viewing angle characteristic evaluation> An antireflector was produced by laminating a polarizing plate, optical anisotropic substance X-1, and a reflector in this order. The positive C plate of optical anisotropic substance X-1 was laminated so that it faced the polarizing plate. The polarizing plate and optical anisotropic substance X-1 were laminated so that the axes of the polarizing plate and the optical anisotropic substance X-1 formed an angle of 45 degrees, and a UV-curable adhesive was used to bond the layers. With this antireflector, the optical anisotropy axis in the horizontal direction was set to 0°, and rotation axes were set at 0° and 90°, respectively. The reflection spectrum in the visible light range (450-650 nm) was measured from angles of 5° to 50° relative to each rotation axis, and the reflection chromaticity was calculated. The reflection chromaticity was expressed as xy coordinates on the xy chromaticity diagram of the CIE color system, and the viewing angle characteristics were expressed as the distance Δxy between the reflection hue in the front direction and the reflection hue in an oblique direction (maximum or minimum value at a polar angle of 50°). A smaller Δxy value indicates better viewing angle characteristics, and the evaluation was based on a five-point scale of A to E below. A: Less than 0.015 B: 0.015 or more and less than 0.03 C: 0.03 or more and less than 0.04 D: 0.04 or more and less than 0.06 E: 0.06 or more

[0178] [Example 2-2] For the optically anisotropic film 1-1, evaluation of the front ellipticity in the visible light region (450 to 650 nm), evaluation of the oblique incidence ellipticity, and evaluation of the viewing angle characteristics using an antireflector were carried out in the same manner as in Example 2-1. In this case, the antireflector was prepared by laminating a polarizing plate, the optically anisotropic film 1-1, and a reflector in this order.

[0179] [Example 2-3] The following materials were mixed in the proportions shown in Table 8 to prepare a polymerizable liquid crystal composition 2-1. The liquid crystal compound used was LC242 (liquid crystal compound L-2) manufactured by BASF Ltd. The liquid crystal compound L-2 is a polymerizable liquid crystal compound that exhibits positive wavelength dispersion and a nematic phase. OXE01 manufactured by BASF was used as the photopolymerization initiator. As the surfactant, S-651 manufactured by AGC Seimi Chemical Co., Ltd. was used.

[0180] [ka]

[0181] [Table 8]

[0182] Polymerizable liquid crystal composition 2-1 dissolved in a mixed solvent (cyclopentanone:1-butanol=63.2:36.8) was spin-coated onto a rubbed glass substrate with an alignment film manufactured by EHC Corporation to form a coating film, which was then heated at 120°C for 1 minute and then allowed to cool to room temperature to form a nematic phase. Under a nitrogen atmosphere, UV light with a wavelength of 365 nm was applied at 50 mW / cm 2 The coating film was irradiated with light under the conditions of 1000 x 30 seconds to polymerize the polymerizable liquid crystal composition 2-1. By adjusting the film thickness, a retardation film α (½ wavelength plate) with a retardation of 264 nm at 522 nm and a retardation film β (¼ wavelength plate) with a retardation of 131 nm at 522 nm were obtained.

[0183] The retardation films α and β were laminated together with the coating surfaces facing inward to produce an optically anisotropic film 2-1. A UV-curable adhesive was used to bond the layers together. The retardation films α and β were laminated together so that the angle between their slow axes was 59°.

[0184] For the optically anisotropic film 2-1, evaluation of the front ellipticity in the visible light region (450 to 650 nm), evaluation of the oblique incidence ellipticity, and evaluation of the viewing angle characteristics using an antireflector were performed in the same manner as in Example 2-1. The antireflector was prepared by laminating a polarizing plate, the optically anisotropic film 2-1, and a reflector in this order. In the ellipticity measurement, the angle between the vibration direction of the incident linearly polarized light and the slow axis of the retardation film α was set to 18.2°.

[0185] [Example 2-4] A positive C plate was attached to the optically anisotropic film 2-1 to produce an optically anisotropic body Y-1. Optical adhesive films were used to attach each layer. NVFILM manufactured by ENEOS Liquid Crystal Corporation was used as the positive C plate. The Rth of the positive C plate was -99.0 nm and the film thickness was 4.4 μm.

[0186] For the optically anisotropic material Y-1, evaluation of the front ellipticity in the visible light region (450 to 650 nm), evaluation of the oblique incidence ellipticity, and evaluation of the viewing angle characteristics using an antireflector were carried out in the same manner as in Example 2-1. In the ellipticity measurement, the angle between the vibration direction of the incident linearly polarized light and the slow axis of the retardation film α was set to 18.2°.

[0187] [Example 2-5] The following materials were mixed in the proportions shown in Table 9 to prepare a polymerizable liquid crystal composition 3-1. Liquid crystal compound L-3 was synthesized based on the method described in JP-A-2010-24438, and is a polymerizable liquid crystal compound that exhibits positive wavelength dispersion. OXE03 manufactured by BASF and Irgacure369E manufactured by BASF were used as photopolymerization initiators. As the surfactant, S-651 manufactured by AGC Seimi Chemical Co., Ltd. was used. A-TMPT manufactured by Shin-Nakamura Chemical Co., Ltd. was used as the monomer.

[0188] [ka]

[0189] [Table 9]

[0190] Polymerizable liquid crystal composition 3-1 dissolved in a mixed solvent (1,2-dichlorobenzene:chloroform = 1:2) was spin-coated onto a rubbed glass substrate with an alignment film manufactured by EHC Corporation to form a coating film, which was then heated at 160°C for 1 minute and allowed to cool to 120°C to form a nematic phase. Under a nitrogen atmosphere, UV light with a wavelength of 365 nm was applied at 50 mW / cm at 120°C. 2 The coating film was irradiated with light for 30 seconds at 1000 W for 30 seconds to polymerize the polymerizable liquid crystal composition 3-1, thereby obtaining an optically anisotropic film 3-1.

[0191] A positive C plate was attached to the optically anisotropic film 3-1 to produce optically anisotropic body Z-1. Optical adhesive films were used to attach each layer. NVFILM manufactured by ENEOS Liquid Crystal Corporation was used as the positive C plate. The Rth of the positive C plate was -99.0 nm and the film thickness was 4.4 μm.

[0192] For the optically anisotropic body Z-1, evaluation of the front ellipticity in the visible light region (450 to 650 nm), evaluation of the oblique incidence ellipticity, and evaluation of the viewing angle characteristics using an antireflector were carried out in the same manner as in Example 2-1.

[0193] Table 10 below shows the results of evaluation of front ellipticity in the visible light region (450 to 650 nm), evaluation of oblique incidence ellipticity, and evaluation of viewing angle characteristics using an antireflector for Examples 2-1 to 2-5. Example 2-1 is an embodiment, Examples 2-2 and 2-3 are reference examples, and Examples 2-4 and 2-5 are comparative examples.

[0194] [Table 10]

[0195] The above results show that the higher the oblique incidence ellipticity in the visible light region (450 to 650 nm), the more excellent the viewing angle characteristics. It can be seen that the optically anisotropic body X-1 of Example 2-1, which is equipped with an optically anisotropic film containing a near-infrared absorbing dye and a positive C plate, has an oblique incidence average ellipticity of 0.90 or more, and is particularly excellent in viewing angle characteristics. On the other hand, in Examples 2-2 to 2-5, the oblique incidence average ellipticity in the visible light region (450 to 650 nm) was less than 0.90, and the viewing angle characteristics were inferior to those of Example 2-1. Comparison between Example 2-1 and Example 2-2, and comparison between Example 2-3 and Example 2-4, showed that the viewing angle characteristics were improved by laminating a positive C plate to the optically anisotropic film. Furthermore, a comparison between Example 2-1 and Example 2-4, and a comparison between Example 2-2 and Example 2-3, showed that the use of optically anisotropic film 1-1 containing a reverse wavelength dispersion liquid crystal compound and a near-infrared absorbing dye has superior viewing angle characteristics compared to optically anisotropic film 2-1 in which two retardation films are bonded together. [Industrial Applicability]

[0196] The optically anisotropic material of this embodiment is useful, for example, as a quarter-wave plate exhibiting excellent viewing angle characteristics or an optical filter in a display device. [Explanation of symbols]

[0197] 1 Optically anisotropic material 2. Optically anisotropic film 3 Positive C Plate

Claims

1. An optically anisotropic body comprising an optically anisotropic film containing a liquid crystal compound exhibiting reverse wavelength dispersion and a near-infrared absorbing dye, and a positive C plate.

2. When the optical anisotropy axis in the horizontal direction is set to 0°, the directions of 0°, 45°, 90°, and 135° are set as rotation axes, respectively. From angles of -50° to 50° (in 10° increments) relative to each of the rotation axes, When linearly polarized light is incident at an angle of 45° to the optical anisotropy axis at normal incidence and measured, An optically anisotropic substance having an average ellipticity of 0.90 or more in the wavelength range of 450 to 650 nm.

3. 2. The optically anisotropic body according to claim 1, wherein the ellipticity of the optically anisotropic film is 0.90 or more over the entire wavelength range of 430 to 680 nm when measured with linearly polarized light incident from a perpendicular direction.

4. 2. The optically anisotropic material according to claim 1, wherein the near-infrared absorbing dye is a compound represented by the following formula (4): 【Chemical 1】 [In formula (4), R ４１ and R ４２ each independently represents a hydrogen atom or a substituent, at least one of which is an electron-withdrawing group; R ４１ and R ４２ may be bonded to form a ring. ４３ each independently represents a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a substituted boron group, or a metal atom; R ４１ may be covalently or coordinately bonded to R Ｌ each independently represents a mesogenic group.

5. 2. The optical anisotropic material according to claim 1, wherein the near-infrared absorbing dye is at least one selected from the group consisting of a compound represented by the following formula (3-1A), a compound represented by the following formula (3-1B), and a compound represented by the following formula (3-2): 【Chemistry 2】 【Chemistry 3】 [In formula (3-1A), formula (3-1B), and formula (3-2), R Ｌ are each independently a mesogenic group. In formula (3-1A), X １ Y each independently represents a carbon atom or a nitrogen atom which may have a monovalent substituent. １ is an oxygen atom, a sulfur atom or an NH group. In formula (3-1B), X ２ are each independently a sulfur atom or an oxygen atom. ２ are each independently a carbon atom or a nitrogen atom which may have a monovalent substituent. In formula (3-1A) and formula (3-1B), R １１ , R １２ R are each independently an alkyl group having 1 to 20 carbon atoms, which may have a substituent and which may contain an unsaturated bond between carbon atoms, an oxygen atom, an alicyclic ring, or an aromatic ring. １３ , R １４ are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. In formula (3-2), R ２１ , R ２２ R are each independently an alkyl group having 1 to 20 carbon atoms, which may have a substituent and which may contain an unsaturated bond between carbon atoms, an oxygen atom, an alicyclic ring, or an aromatic ring. ２３ are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms.

6. 2. The optically anisotropic body according to claim 1, further comprising an adhesive layer between the optically anisotropic film and the positive C plate.

7. An optical filter comprising the optically anisotropic body according to any one of claims 1 to 6.

8. An image display device comprising the optically anisotropic body according to any one of claims 1 to 6.

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