Optical films and electroluminescent display devices

Abstract

The present invention addresses the problem of providing: an optical film that, when used for a micro LED, can suppress a reduction in transmittance at the front face and can suppress a change in color in a direction diagonal to the front face; and an electroluminescence display device. This optical film has a light absorption anisotropic layer containing a dichroism pigment compound. The light absorption anisotropic layer has an absorption axis in the direction normal to the film, and demonstrates a degree of orientation at 530 nm of 0.7 or greater. The optical film satisfies both formulas (1) and (2) when, at an angle of 45° with respect to the normal direction, the 460 nm, 530 nm, and 630 nm transmittances of the optical film are respectively defined as Tb, Tg and Tr.　Formulas: (1) 0.1 ≤ Tb / Tr ≤ 0.5; (2) 0.2 ≤ Tg / Tr ≤ 0.6

Description

[Technical Field]

[0001] The present invention relates to optical films and electroluminescent display devices. [Background technology]

[0002] LED displays using light-emitting diodes (LEDs), which are self-luminous elements, are being developed. In particular, microLED displays, which incorporate chip-shaped microLEDs, have been developed and have recently attracted attention as display devices that can easily achieve both high resolution and large size.

[0003] In micro-LEDs, InGaN / GaN is generally used for the G (green) and B (blue) light-emitting elements, and GaInP / AlGaInP is used for the R (red) light-emitting element. Due to the difference in refractive index, when the color is adjusted to be neutral in the forward direction, the color shifts in the oblique direction, and a phenomenon occurs where the brightness derived from G (green) and B (blue) becomes higher (Non-Patent Literature 1). [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Optics Express 27(12)A746-A757 [Overview of the project] [Problems that the invention aims to solve]

[0005] The inventors investigated placing a layer containing G and B absorbers on the surface of a microLED in order to neutralize the color in oblique directions. They found that while it is possible to neutralize the color in oblique directions, this significantly reduces the transmittance in the front direction.

[0006] Accordingly, an object of the present invention is to provide an optical film and an electroluminescent display device that can suppress a decrease in front transmittance and suppress a change in color tone in an oblique direction relative to the front face when used in a micro LED. [Means for Solving the Problem]

[0007] As a result of intensive studies to achieve the above object, the inventors of the present invention found that, for an optical film having a light-absorbing anisotropic layer containing a dichroic dye compound, when the light-absorbing anisotropic layer has an absorption axis in the normal direction of the film, has an orientation degree of 0.7 or more at 530 nm, and the optical film satisfies a specific relationship between transmittances at specific wavelengths in a direction at 45° relative to the normal direction of the film, the optical film can suppress a decrease in front transmittance and suppress a change in color tone in an oblique direction relative to the front face when used in a micro LED, and thus arrived at the present invention. That is, the inventors of the present invention have found that the above object can be achieved by the following constitution.

[0008] [1] An optical film having a light-absorbing anisotropic layer containing a dichroic dye compound, wherein the light-absorbing anisotropic layer has an absorption axis in the normal direction of the film, and has an orientation degree of 0.7 or more at 530 nm, and when transmittances of the optical film at 460 nm, 530 nm, and 630 nm in a direction at 45° relative to the normal direction of the film are defined as Tb, Tg, and Tr, respectively, the optical film satisfies both of the relationships of the following formulas (1) and (2): 0.1 ≦ Tb / Tr ≦ 0.5 (1) 0.2 ≦ Tg / Tr ≦ 0.6 (2) [2] The optical film according to [1], wherein the light-absorbing anisotropic layer contains two or more types of dichroic dye compounds. [3] The optical film according to [1] or [2], wherein the light-absorbing anisotropic layer contains a dichroic dye compound having an absorption peak at 430 nm or more and less than 500 nm, and a dichroic dye compound having an absorption peak at 500 nm or more and 560 nm or less. [4] The optical film according to any one of [1] to [3], wherein a transmittance at 530 nm in a normal direction of the film is 50% or more. [5] The optical film according to any one of [1] to [4], wherein a transmittance at 530 nm in a normal direction of the film is 70% or more. [6] The optical film according to any one of [1] to [5], wherein a transmittance at 630 nm in a normal direction of the film is 75% or more. [7] An electroluminescent display device, wherein the optical film according to any one of [1] to [6] is laminated on an electroluminescent substrate having a plurality of colors of electroluminescent light-emitting elements. [8] The electroluminescent display device according to [7], wherein the light-emitting element is a light-emitting diode. [9] The electroluminescent display device according to [8], wherein the light-emitting diodes have three colors of red, green and blue, and when luminances at 460 nm, 530 nm and 630 nm in a normal direction of the electroluminescent display device are defined as Lb, Lg and Lr respectively, both of the relationships of the following formulas (3) and (4) are satisfied. 3≦Lg / Lb≦8 (3) 0.5≦Lr / Lb≦2.5 (4) Effects of the Invention

[0009] According to the present invention, when micro LEDs are used, it is possible to provide an optical film and an electroluminescent display device that can suppress a decrease in front transmittance and suppress a change in color tone in an oblique direction with respect to the front. Mode for Carrying Out the Invention

[0010] Hereinafter, the present invention will be described in detail. The following description of the constitutional requirements may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, a numerical range represented by "~" means a range that includes the numbers written before and after "~" as the lower and upper limits, respectively. Furthermore, in this specification, parallel, orthogonal, and normal do not mean parallel, orthogonal, and normal in the strict sense, respectively, but rather mean a range of ±5° from parallel, orthogonal, and normal, respectively.

[0011] Furthermore, in this specification, the terms "liquid crystal composition" and "liquid crystal compound" also include, conceptually, materials that no longer exhibit liquid crystal properties due to curing or other reasons. Furthermore, in this specification, each component may be represented by a single substance or by a combination of two or more substances. When two or more substances are used in combination for each component, the content of that component refers to the total content of the combined substances, unless otherwise specified. Furthermore, in this specification, "(meth)acrylate" refers to "acrylate" or "methacrylate," "(meth)acrylic" refers to "acrylic" or "methacrylic," and "(meth)acryloyl" refers to "acryloyl" or "methacryloyl."

[0012] In this invention, visible light refers to electromagnetic waves with wavelengths visible to the human eye, specifically light in the wavelength range of 380 to 780 nm. Non-visible light refers to light in the wavelength range of less than 380 nm and light in the wavelength range of more than 780 nm.

[0013] [Optical film] The optical film of the present invention is an optical film having a light-absorbing anisotropic layer containing a dichroic dye compound. Furthermore, the optical film of the present invention has an anisotropic light absorption layer that has an absorption axis in the direction normal to the film and has an orientation degree of 0.7 or higher at 530 nm. Furthermore, the optical film of the present invention is an optical film that satisfies both of the following relationships (1) and (2), when the transmittances at 460 nm, 530 nm, and 630 nm in a direction 45° with respect to the film normal are defined as Tb, Tg, and Tr, respectively. 0.1 ≤ Tb / Tr ≤ 0.5 (1) 0.2 ≤ Tg / Tr ≤ 0.6 (2)

[0014] Here, with respect to the light-absorbing anisotropic layer, "having an absorption axis in the direction of the film normal" means that the absorption axis is within ±5° of the normal direction of the surface of the light-absorbing anisotropic layer, that is, the normal direction in the strict sense (90°). Furthermore, the absorption axis refers to the direction of the absorption axis (the long axis direction of the molecule) of the dichroic dye compound contained in the light-absorbing anisotropic layer. In the present invention, it can be identified as the direction that shows the highest transmittance when the transmittance is measured by changing the tilt angle (polar angle) and tilt direction (azimuthal angle) with respect to the normal direction of the surface of the light-absorbing anisotropic layer. Specifically, the Müller matrix at a wavelength of 550 nm is measured using an AxoScan OPMF-1 (OptoScience Co., Ltd.). More specifically, during the measurement, the azimuthal angle at which the absorption axis is tilted is first identified. Then, within a plane containing the normal direction of the anisotropic light-absorbing layer along that azimuthal angle (a plane containing the absorption axis and perpendicular to the layer surface), the polar angle, which is the angle between the normal direction of the anisotropic light-absorbing layer surface, is changed in 1° increments from -70 to 70°, and the Müller matrix at a wavelength of 550 nm is measured, and the transmittance of the anisotropic light-absorbing layer is derived. The direction with the highest transmittance is then defined as the absorption axis.

[0015] Furthermore, with respect to optical films, "transmittance at 460nm, 530nm, and 630nm in a direction 45° from the film normal direction" refers to the values ​​obtained by measurement as follows. First, the Müller matrix of the optical film at each measurement wavelength is measured using the AxoScan OPMF-1 (OptoScience Co., Ltd.). Specifically, the polar angle, which is the angle with respect to the normal direction of the optical film, is set to 45°, and the Müller matrix at each measurement wavelength is measured to derive the transmittance of the optical film. Furthermore, when measuring transmittance, the normal direction that serves as the reference for the polar angle shall be defined as the normal direction in the strict sense (90°).

[0016] In the present invention, as described above, the light-absorbing anisotropic layer has an absorption axis in the direction normal to the film and an orientation degree of 0.7 or more at 530 nm, and the optical film satisfies the relationship between equations (1) and (2) above in terms of transmittance at a specific wavelength in a direction 45° from the film normal direction. As a result, when used in a micro-LED, it is possible to suppress the decrease in transmittance at the front and suppress the change in color at an oblique direction relative to the front. Although this is not entirely clear, the inventors speculate the following: In other words, the reduction in transmittance on the front surface can be suppressed because the light-absorbing anisotropic layer has an absorption axis in the direction normal to the film and its orientation degree at 530 nm is 0.7 or higher. This is thought to be because the dichroic dye compound contained in the light-absorbing anisotropic layer is oriented perpendicular to the surface of the light-absorbing anisotropic layer, resulting in higher transmittance in the direction along the absorption axis of the light-absorbing anisotropic layer. Furthermore, the optical film can suppress color changes in oblique directions relative to the front by satisfying the relationship between equations (1) and (2) above, which is the transmittance of a specific wavelength at a 45° angle to the film normal direction. This is thought to be because, by satisfying the relationship between equations (1) and (2), the luminance ratios of red, green, and blue that affect color changes in oblique directions approximate the luminance ratios of red, green, and blue when the color in the front direction is adjusted to be neutral.

[0017] As described above, the optical film of the present invention satisfies both of the following relationships (1) and (2) when the transmittances at 460nm, 530nm, and 630nm in a direction 45° with respect to the film normal are defined as Tb(45), Tg(45), and Tr(45), respectively. However, it is preferable that both of the following relationships (1-2) and (2-2) are satisfied in order to further suppress color changes in oblique directions. 0.1 ≤ Tb(45) / Tr(45) ≤ 0.5 (1) 0.2 ≤ Tg(45) / Tr(45) ≤ 0.6 (2) 0.2≦Tb(45) / Tr(45)≦0.4 (1-2) 0.3≦Tg(45) / Tr(45)≦0.5 (2-2)

[0018] Furthermore, in the optical film of the present invention, when the transmittances at 450 nm, 530 nm, and 630 nm in the direction normal to the film are defined as Tb(0), Tg(0), and Tr(0), respectively, Tb(0) is preferably 50% or more, and more preferably 70% or more. Similarly, Tg(0) is preferably 50% or more, and more preferably 70% or more. Furthermore, Tr(0) is preferably 75% or more, and more preferably 80% or more. This makes it possible to further suppress the decrease in transmittance at the front. Here, the transmittance at each wavelength in the direction normal to the film refers to the value obtained by measuring and calculating as follows. First, the Mueller matrix of the optical film at each measurement wavelength is measured using an AxoScan OPMF-1 (OptoScience Co., Ltd.). Specifically, the polar angle, which is the angle of the optical film with respect to the normal direction, is measured at 5° intervals from -70° to 70°. The transmittance (front transmittance) at each wavelength is calculated from the average values ​​of Tmax and Tmin from these measurement results.

[0019] [Light-absorbing anisotropic layer] As described above, the light-absorbing anisotropic layer of the optical film of the present invention has absorption in the direction normal to the film. Here, to control the absorption axis of the light-absorbing anisotropic layer, it is preferable to orient a dichroic dye compound (for example, an organic dichroic dye) as described later, and it is even more preferable to orient the dichroic dye compound using the orientation of a liquid crystalline compound. An example of such a preferred configuration is a light-absorbing anisotropic layer in which at least one dichroic dye compound is oriented perpendicular to the plane.

[0020] Techniques for oriented dichroic dye compounds to a desired orientation can be based on techniques for fabricating polarizers using dichroic dye compounds and techniques for fabricating guest-host liquid crystal cells. For example, techniques used in the fabrication methods for dichroic polarizing elements described in Japanese Patent Publication No. 11-305036 and Japanese Patent Publication No. 2002-90526, and in the fabrication methods for guest-host type liquid crystal display devices described in Japanese Patent Publication No. 2002-99388 and Japanese Patent Publication No. 2016-27387 can also be used to fabricate the light-absorbing anisotropic layer used in the present invention.

[0021] For example, by utilizing guest-host liquid crystal cell technology, the molecules of a dichroic dye compound can be oriented in accordance with the orientation of the host liquid crystal, as described above. Specifically, by mixing a guest dichroic dye compound with a rod-shaped liquid crystalline compound that serves as the host liquid crystal, oriented the host liquid crystal, and oriented the molecules of the dichroic dye compound along the orientation of the liquid crystal molecules, thereby fixing the orientation, a light-absorbing anisotropic layer used in the present invention can be fabricated.

[0022] To prevent variations in the light absorption properties of the light-absorbing anisotropic layer used in the present invention due to the operating environment, it is preferable to fix the orientation of the dichroic dye compound by forming chemical bonds. For example, the orientation can be fixed by promoting polymerization of the host liquid crystal, the dichroic dye compound, or optionally added polymerizable components.

[0023] Furthermore, by impregnating a polymer film with a dichroic dye compound and orienting the dichroic dye compound along the orientation of the polymer molecules in the polymer film, a polymer film that satisfies the light absorption characteristics required for the light absorption anisotropy layer used in the present invention can be produced. Specifically, this can be done by coating a solution of the dichroic dye compound onto the surface of the polymer film and allowing it to penetrate the film. The orientation of the dichroic dye compound can be adjusted by the orientation of the polymer chains in the polymer film, their properties (chemical and physical properties of the polymer chains or the functional groups they possess), the coating method, etc. Details of this method are described in Japanese Patent Application Publication No. 2002-90526.

[0024] Furthermore, as described above, the optical film of the present invention has an orientation degree S at 530 nm of 0.7 or higher in the optical film, but it is preferable that it be 0.9 or higher in order to further suppress the decrease in transmittance on the front surface. Here, the degree of orientation measured at a wavelength of λnm shall be defined in this specification as follows: Using the AxoScan OPMF-1 (OptoScience Co., Ltd.), the Mueller matrix at a wavelength of 530 nm is measured at each pole angle, while changing the pole angle (the angle relative to the normal direction of the optical absorption anisotropy layer) from 0 to 90° in 5° increments, and the minimum transmittance (Tmin) is derived. Next, after removing the effect of surface reflection, the Tmin at the pole angle where Tmin is highest is defined as Tm(0), and the Tmin at the direction where the pole angle is increased by another 40° from the pole angle with the highest Tmin is defined as Tm(40). Absorbance is calculated from the obtained Tm(0) and Tm(40) using the following formula to calculate A(0) and A(40). A = -log(Tm) Here, Tm represents transmittance and A represents absorbance. From the calculated A(0) and A(40), the degree of orientation S at a wavelength of 530 nm is calculated using the following formula. S=(4.6×A(40)-A(0)) / (4.6×A(40)+2×A(0))

[0025] <Dichroic dye compounds> The dichroic dye compound included in the light-absorbing anisotropic layer is not particularly limited, and conventionally known dichroic dye compounds can be used, with the use of a dichroic azo dye compound being particularly preferred. The dichroic azo dye compound is not particularly limited, and conventionally known dichroic azo dyes can be used, but the compounds described below are preferred.

[0026] In this invention, a dichroic azo dye compound means a dye whose absorbance differs depending on the direction. The dichroic azo dye compound may or may not exhibit liquid crystalline properties. When a dichroic azo dye compound exhibits liquid crystalline properties, it may exhibit either nematic or smectic properties. The temperature range in which the liquid crystalline phase is exhibited is preferably room temperature (approximately 20°C to 28°C) to 300°C, and more preferably 50°C to 200°C from the viewpoint of handling and manufacturing suitability.

[0027] In the present invention, from the viewpoint of color adjustment, it is preferable that the light-absorbing anisotropic layer contains two or more dichroic dye compounds (particularly dichroic azo dye compounds).

[0028] Furthermore, in the present invention, from the viewpoint of color adjustment, it is preferable that the light absorption anisotropy layer contains a dichroic dye compound having an absorption peak at a wavelength of 430 nm to 560 nm, and more preferably contains at least one dichroic dye compound having an absorption peak at a wavelength of 430 nm to less than 500 nm (for example, a second dichroic azo dye compound described later) and at least one dichroic dye compound having an absorption peak at a wavelength of 500 nm to 560 nm (for example, a first dichroic azo dye compound described later). Specifically, it is particularly preferable that it contains at least a dichroic azo dye compound represented by formula (5) described later and a dichroic azo dye compound represented by formula (6) described later.

[0029] Furthermore, in the present invention, from the viewpoint of color adjustment, it is preferable that the light-absorbing anisotropic layer does not contain a dichroic dye compound having an absorption peak at a wavelength of 600 nm to 700 nm, and more preferably that it does not contain a dichroic dye compound having absorption at a wavelength of 600 nm to 700 nm.

[0030] In the present invention, from the viewpoint of achieving better pressure resistance, it is preferable that the dichroic azo dye compound has a crosslinking group. Examples of crosslinkable groups include (meth)acryloyl groups, epoxy groups, oxetanyl groups, and styryl groups, with (meth)acryloyl groups being preferred.

[0031] (First dichroic azo dye compound) The first dichroic azo dye compound is preferably a compound having a chromophore, which is the core of the dichroic azo dye compound, and a side chain bound to the end of the chromophore. Specific examples of chromophores include aromatic ring groups (e.g., aromatic hydrocarbon groups, aromatic heterocyclic groups) and azo groups. Structures having both aromatic hydrocarbon groups and azo groups are preferred, and bisazo or trisazo structures having an aromatic hydrocarbon group and two or three azo groups are more preferred. The side chain is not particularly limited and may include groups represented by R4, R5, or R6 in formula (5) described later.

[0032] The first dichroic azo dye compound is a dichroic azo dye compound having a maximum absorption wavelength in the range of 500 nm to 560 nm. From the viewpoint of color adjustment, it is preferably a dichroic azo dye compound having a maximum absorption wavelength in the range of 510 to 550 nm, and more preferably a dichroic azo dye compound having a maximum absorption wavelength in the range of 520 to 540 nm.

[0033] The first dichroic azo dye compound is preferably the compound represented by formula (5) because it further improves the orientation of the polarizer.

[0034] Formula (5) [ka]

[0035] In equation (5), n represents either 1 or 2. In formula (5), Ar3, Ar4, and Ar5 each independently represent an optionally substituted phenylene group, an optionally substituted naphthylene group, or an optionally substituted heterocyclic group. The heterocyclic group may be either aromatic or non-aromatic. Atoms other than carbon that constitute an aromatic heterocyclic group include nitrogen, sulfur, and oxygen atoms. If an aromatic heterocyclic group has multiple atoms other than carbon that constitute the ring, these may be the same or different. Specific examples of aromatic heterocyclic groups include pyridylene (pyridine-diyl group), pyridazine-diyl group, imidazole-diyl group, thienylene (thiophene-diyl group), quinolylene (quinoline-diyl group), isoquinolylene (isoquinoline-diyl group), oxazole-diyl group, thiazole-diyl group, oxadiazole-diyl group, benzothiazole-diyl group, benzothiadiazole-diyl group, phthalimide-diyl group, thienothiazole-diyl group, thiazolothiazole-diyl group, thienothiophene-diyl group, and thienoxazole-diyl group.

[0036] In formula (5), R4 represents a hydrogen atom, a linear or branched alkyl group which may have substituents having 1 to 20 carbon atoms, an alkoxy group, an alkylthio group, an alkylsulfonyl group, an alkylcarbonyl group, an alkyloxycarbonyl group, an acyloxy group, an alkylcarbonate group, an alkylamino group, an acylamino group, an alkylcarbonylamino group, an alkoxycarbonylamino group, an alkylsulfonylamino group, an alkylsulfamoyl group, an alkylcarbamoyl group, an alkylsulfinyl group, an alkylureido group, an alkylphosphate amide group, an alkylimino group, or an alkylsilyl group. The -CH2- groups constituting the above alkyl groups may be substituted with -O-, -CO-, -C(O)-O-, -OC(O)-, -Si(CH3)2-O-Si(CH3)2-, -N(R1')-, -N(R1')-CO-, -CO-N(R1')-, -N(R1')-C(O)-O-, -OC(O)-N(R1')-, -N(R1')-C(O)-N(R1')-, -CH=CH-, -C≡C-, -N=N-, -C(R1')=CH-C(O)-, or -OC(O)-O-. If R4 is a group other than a hydrogen atom, the hydrogen atoms in each group may be substituted with a halogen atom, a nitro group, a cyano group, -N(R1')2, an amino group, -C(R1')=C(R1')-NO2, -C(R1')=C(R1')-CN, or -C(R1')=C(CN)2. R1' represents a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms. If multiple R1' elements exist in each group, they may be the same or different from one another.

[0037] In formula (5), R5 and R6 each independently represent a hydrogen atom, a linear or branched alkyl group which may have substituents having 1 to 20 carbon atoms, an alkoxy group, an acyl group, an alkyloxycarbonyl group, an alkylamide group, an alkylsulfonyl group, an aryl group, an arylcarbonyl group, an arylsulfonyl group, an aryloxycarbonyl group, or an arylamide group. The -CH2- constituting the above alkyl group may be substituted with -O-, -S-, -C(O)-, -C(O)-O-, -OC(O)-, -C(O)-S-, -SC(O)-, -Si(CH3)2-O-Si(CH3)2-, -NR2'-, -NR2'-CO-, -CO-NR2'-, -NR2'-C(O)-O-, -OC(O)-NR2'-, -NR2'-C(O)-NR2'-, -CH=CH-, -C≡C-, -N=N-, -C(R2')=CH-C(O)-, or -OC(O)-O-. If R2 and R3 are groups other than hydrogen atoms, the hydrogen atoms in each group may be substituted with halogen atoms, nitro groups, cyano groups, -OH groups, -N(R2')2, amino groups, -C(R2')=C(R2')-NO2, -C(R2')=C(R2')-CN, or -C(R2')=C(CN)2. R2' represents a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms. If multiple R2' elements exist in each group, they may be identical or different from one another. R5 and R6 may bond to each other to form a ring, or R5 or R6 may bond to Ar2 to form a ring.

[0038] From the viewpoint of lightfastness, R4 is preferably an electron-withdrawing group, and R5 and R6 are preferably groups with low electron-donating properties. Among these groups, a specific example when R4 is an electron-withdrawing group is the same as a specific example when R1 is an electron-withdrawing group, and a specific example when R5 and R6 are groups with low electron-donating properties is the same as a specific example when R2 and R3 are groups with low electron-donating properties.

[0039] Specific examples of the first dichroic azo dye compound are shown below, but are not limited to these.

[0040] [ka] JPEG0007920053000003.jpg155111 JPEG0007920053000004.jpg160105 JPEG0007920053000005.jpg167111

[0041] (Second dichroic azo dye compound) The second dichroic azo dye compound is a dichroic azo dye compound other than the first dichroic azo dye compound, and specifically, it has a different chemical structure from the first dichroic azo dye compound. The second dichroic azo dye compound is a dichroic azo dye compound having a maximum absorption wavelength in the range of 430 nm to less than 500 nm. From the viewpoint of color adjustment, it is preferably a dichroic azo dye compound having a maximum absorption wavelength in the range of 440 to 490 nm, and more preferably a dichroic azo dye compound having a maximum absorption wavelength in the range of 450 to 480 nm.

[0042] The second dichroic azo dye compound preferably contains a dichroic azo dye represented by the following formula (6).

[0043] [ka]

[0044] In formula (6), A and B each independently represent a crosslinkable group. In formula (6), a and b each independently represent either 0 or 1. For superior orientation at 420 nm, it is preferable that both a and b are 0. In equation (6), when a=0, L1 represents a monovalent substituent, and when a=1, L1 represents a single bond or a divalent linking group. Also, when b=0, L2 represents a monovalent substituent, and when b=1, L2 represents a single bond or a divalent linking group. In formula (6), Ar1 represents an (n1+2) valent aromatic hydrocarbon group or heterocyclic group, Ar2 represents an (n2+2) valent aromatic hydrocarbon group or heterocyclic group, and Ar3 represents an (n3+2) valent aromatic hydrocarbon group or heterocyclic group. In equation (6), R1, R2, and R3 each independently represent a monovalent substituent. If n1 ≥ 2, the multiple R1s may be identical or different from each other; if n2 ≥ 2, the multiple R2s may be identical or different from each other; and if n3 ≥ 2, the multiple R3s may be identical or different from each other. In equation (6), k represents an integer from 1 to 4. When k ≥ 2, multiple Ar2s may be identical or different from each other, and multiple R2s may be identical or different from each other. In equation (6), n1, n2, and n3 each independently represent integers from 0 to 4. However, when k=1, n1+n2+n3≧0, and when k≧2, n1+n2+n3≧1.

[0045] In formula (6), examples of the crosslinkable groups represented by A and B include the polymerizable groups described in paragraphs

[0040] to

[0050] of Japanese Patent Application Publication No. 2010-244038. Among these, acryloyl groups, methacryloyl groups, epoxy groups, oxetanyl groups, and styryl groups are preferred from the viewpoint of improving reactivity and synthetic suitability, and acryloyl groups and methacryloyl groups are more preferred from the viewpoint of further improving solubility.

[0046] In equation (6), when a=0, L1 represents a monovalent substituent, and when a=1, L1 represents a single bond or a divalent linking group. Also, when b=0, L2 represents a monovalent substituent, and when b=1, L2 represents a single bond or a divalent linking group.

[0047] The monovalent substituents represented by L1 and L2 are preferably groups introduced to enhance the solubility of the dichroic dye compound, or electron-donating or electron-withdrawing groups introduced to adjust the color tone of the dye. For example, as a substituent, Alkyl groups (preferably C1-C20, more preferably C1-C12, particularly preferably C1-C8 alkyl groups, such as methyl, ethyl, isopropyl, tert-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, and cyclohexyl groups), Alkenyl group (preferably an alkenyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms, such as vinyl group, allyl group, 2-butenyl group, 3-pentenyl group, etc.), Alkynyl group (preferably an alkynyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms; for example, propargyl group, 3-pentinyl group, etc.), Aryl group (preferably an aryl group having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 12 carbon atoms, such as a phenyl group, a 2,6-diethylphenyl group, a 3,5-ditrifluoromethylphenyl group, a naphthyl group, and a biphenyl group), Substituted or unsubstituted amino groups (preferably amino groups having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, and particularly preferably 0 to 6 carbon atoms, such as unsubstituted amino groups, methylamino groups, dimethylamino groups, diethylamino groups, anilino groups, etc.), Alkoxy groups (preferably having 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, for example, methoxy groups, ethoxy groups, butoxy groups, etc.), Oxycarbonyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 15 carbon atoms, and particularly preferably 2 to 10 carbon atoms; examples include methoxycarbonyl group, ethoxycarbonyl group, phenoxycarbonyl group, etc.), Acyloxy group (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, for example, acetoxy group and benzoyloxy group), Acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, for example, acetylamino group and benzoylamino group), Alkoxycarbonylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, for example, a methoxycarbonylamino group), Aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms, for example, a phenyloxycarbonylamino group), Sulfonylamino group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, for example, methanesulfonylamino group, benzenesulfonylamino group, etc.), Sulfamoyl group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, and particularly preferably 0 to 6 carbon atoms; examples include sulfamoyl group, methylsulfamoyl group, dimethylsulfamoyl group, phenylsulfamoyl group, etc.), Carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 1 to 6 carbon atoms, for example, an unsubstituted carbamoyl group, a methyl carbamoyl group, a diethyl carbamoyl group, a phenyl carbamoyl group, etc.), Alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, for example, a methylthio group, an ethylthio group, etc.), Arylthio group (preferably having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, for example, a phenylthio group), Sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, for example, a mesyl group, a tosyl group, etc.), Sulfinyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 1 to 6 carbon atoms; for example, methanesulfinyl group, benzenesulfinyl group, etc.), Ureido group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 1 to 6 carbon atoms; examples include unsubstituted ureido group, methylureido group, phenylureido group, etc.), A phosphate amide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 1 to 6 carbon atoms; for example, a diethyl phosphate amide group, a phenyl phosphate amide group, etc.), Heterocyclic group (preferably a heterocyclic group having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms, for example, a heterocyclic group having a hetero atom such as a nitrogen atom, an oxygen atom, a sulfur atom, and examples thereof include an imidazolyl group, a pyridyl group, a quinolyl group, a furyl group, a piperidyl group, a morpholino group, a benzoxazolyl group, a benzimidazolyl group, a benzthiazolyl group, etc.), Silyl group (preferably a silyl group having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms, and examples thereof include a trimethylsilyl group, a triphenylsilyl group, etc.), Halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom), Hydroxy group, mercapto group, cyano group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, and azo group can be used. These substituents may be further substituted with these substituents. When two or more substituents are present, they may be the same or different. If possible, they may be bonded to each other to form a ring. Examples of groups in which the above substituent is further substituted with the above substituent include groups in which an alkoxy group is substituted with an alkyl group, that is, R B -(O-R A ) na - group. In the formula, R A represents an alkylene group having 1 to 5 carbon atoms, R B represents an alkyl group having 1 to 5 carbon atoms, and na represents an integer of 1 to 10 (preferably 1 to 5, more preferably 1 to 3). Among these, as the monovalent substituent represented by L1 and L2, an alkyl group, an alkenyl group, an alkoxy group, and a group obtained by further substituting these groups with these groups (for example, the aforementioned R B -(O-R A ) na - group) are preferable, and an alkyl group, an alkoxy group, and a group obtained by further substituting these groups with these groups (for example, the aforementioned R B -(O-R A ) na - group) are more preferable.

[0048] Examples of divalent linking groups represented by L1 and L2 include -O-, -S-, -CO-, -COO-, -OCO-, -O-CO-O-, and -CO-NR. N -, -O-CO-NR N -, -NR N -CO-NR N Examples include -, -SO2-, -SO-, alkylene groups, cycloalkylene groups, and alkenylene groups, as well as groups formed by combining two or more of these groups. Among these, a group formed by combining an alkylene group with one or more groups selected from the group consisting of -O-, -COO-, -OCO-, and -O-CO-O- is preferred. Here, R N R represents a hydrogen atom or an alkyl group. N If there are multiple R N They may be the same or different from each other.

[0049] From the viewpoint of further improving the solubility of the dichroic dye compound, the number of atoms in at least one of the main chains of L1 and L2 is preferably 3 or more, more preferably 5 or more, even more preferably 7 or more, and particularly preferably 10 or more. Furthermore, the upper limit of the number of atoms in the main chain is preferably 20 or less, and more preferably 12 or less. On the other hand, from the viewpoint of further improving the orientation of the light-absorbing anisotropic layer, it is preferable that the number of atoms in at least one of the main chains of L1 and L2 be 1 to 5. Here, if A exists in equation (6), the "main chain" in L1 refers to the part necessary to directly connect the "O" atom that connects to L1 and "A", and the "number of atoms in the main chain" refers to the number of atoms that make up the above part. Similarly, if B exists in equation (6), the "main chain" in L2 refers to the part necessary to directly connect the "O" atom that connects to L2 and "B", and the "number of atoms in the main chain" refers to the number of atoms that make up the above part. Note that the "number of atoms in the main chain" does not include the number of atoms in the branched chain, which will be discussed later. Furthermore, if A does not exist, the "number of atoms in the main chain" in L1 refers to the number of atoms in L1 that do not include branched chains. If B does not exist, the "number of atoms in the main chain" in L2 refers to the number of atoms in L2 that do not include branched chains. Specifically, in equation (D1) below, the number of atoms in the L1 main chain is 5 (the number of atoms in the dotted box on the left side of equation (D1) below), and the number of atoms in the L2 main chain is 5 (the number of atoms in the dotted box on the right side of equation (D1) below). Also, in equation (D10) below, the number of atoms in the L1 main chain is 7 (the number of atoms in the dotted box on the left side of equation (D10) below), and the number of atoms in the L2 main chain is 5 (the number of atoms in the dotted box on the right side of equation (D10) below).

[0050] [ka]

[0051] L1 and L2 may have branched chains. Here, if A is present in equation (6), the "branched chain" in L1 refers to the part of L1 other than the part necessary to directly connect the "O" atom that connects to L1 in equation (6) and "A". Similarly, if B is present in equation (6), the "branched chain" in L2 refers to the part of L2 other than the part necessary to directly connect the "O" atom that connects to L2 in equation (6) and "B". Furthermore, if A does not exist in equation (6), the "branched chain" in L1 refers to the portion other than the longest atomic chain (i.e., the main chain) that extends from the "O" atom connected to L1 in equation (6). Similarly, if B does not exist in equation (6), the "branched chain" in L2 refers to the portion other than the longest atomic chain (i.e., the main chain) that extends from the "O" atom connected to L2 in equation (6). The number of atoms in the branched chain is preferably three or less. Having three or fewer atoms in the branched chain offers advantages such as improved orientation of the light-absorbing anisotropic layer. Note that the number of hydrogen atoms is not included in the number of atoms in the branched chain.

[0052] In equation (6), Ar1 represents an aromatic hydrocarbon group or heterocyclic group with (n1+2) valency (for example, trivalent when n1 is 1), Ar2 represents an aromatic hydrocarbon group or heterocyclic group with (n2+2) valency (for example, trivalent when n2 is 1), and Ar3 represents an aromatic hydrocarbon group or heterocyclic group with (n3+2) valency (for example, trivalent when n3 is 1). Here, Ar1 to Ar3 can be rephrased as a divalent aromatic hydrocarbon group or a divalent heterocyclic group substituted with n1 to n3 substituents (R1 to R3 described later). The divalent aromatic hydrocarbon group represented by Ar1 to Ar3 may be a monocyclic or have a fused ring structure of two or more rings. From the viewpoint of improving solubility, the number of rings in the divalent aromatic hydrocarbon group is preferably 1 to 4, more preferably 1 to 2, and even more preferably 1 (i.e., a phenylene group). Specific examples of divalent aromatic hydrocarbon groups include phenylene groups, azulene-diyl groups, naphthylene groups, fluorene-diyl groups, anthracene-diyl groups, and tetracene-diyl groups. From the viewpoint of improving solubility, phenylene groups and naphthylene groups are preferred, with phenylene groups being more preferred. The following are specific examples of the second dichroic dye compound, but the present invention is not limited to these. In the following examples, n represents an integer from 1 to 10.

[0053] [ka]

[0054] [ka]

[0055] In terms of excellent orientation at 460 nm, a structure in which the second dye does not have radical polymerizable groups is preferred. For example, the following structure can be cited. [ka] JPEG0007920053000011.jpg11119

[0056] The second dichroic azo dye compound is more preferably a dichroic dye compound having a structure represented by the following formula (1-1), as it exhibits particularly excellent orientation at 460 nm.

[0057] [ka]

[0058] In equation (1-1), the definitions of R1, R3, R4, R5, n1, n3, L1, and L2 are equivalent to the definitions of R1, R3, R4, R5, n1, n3, L1, and L2 in equation (3), respectively. In formula (1-1), R 21 and R 22 Each of these definitions is independent and equivalent to R2 in equation (3). In equation (1-1), the definitions of n21 and n22 are independently synonymous with n2 in equation (3). n1+n21+n22+n3≧1, where n1+n21+n22+n3 is preferably 1 to 9, and more preferably 1 to 5.

[0059] The following are specific examples of the second dichroic dye compound, but the present invention is not limited to these.

[0060] [ka]

[0061] [ka]

[0062] [ka]

[0063] (Content of dichroic pigment compounds) The content of the dichroic dye compound is preferably 5 to 30% by mass, more preferably 8 to 20% by mass, and even more preferably 10 to 15% by mass, relative to the total solid content mass of the light-absorbing anisotropic layer, because it makes it easier to adjust the degree of orientation of the light-absorbing anisotropic layer to 0.7 or higher. Furthermore, the content of the first dichroic azo dye compound is preferably 30 to 80% by mass, and more preferably 40 to 70% by mass, relative to the total mass of the dichroic dye compounds in the light-absorbing anisotropic layer, because it makes it easier to adjust the degree of orientation of the light-absorbing anisotropic layer to 0.7 or higher. The content of the second dichroic azo dye compound is preferably 20 to 70% by mass, and more preferably 30 to 60% by mass, relative to the total mass of the dichroic dye compounds in the light-absorbing anisotropic layer, because it makes it easier to adjust the degree of orientation of the light-absorbing anisotropic layer to 0.7 or higher.

[0064] <Liquid crystal compounds> The light-absorbing anisotropic layer preferably contains a liquid crystalline compound. By including a liquid crystalline compound, the precipitation of the dichroic dye compound can be suppressed while the dichroic dye compound can be oriented with a high degree of orientation. Liquid crystalline compounds are liquid crystalline compounds that do not exhibit dichroism. As the liquid crystalline compound, either a low-molecular-weight liquid crystalline compound or a high-molecular-weight liquid crystalline compound can be used, and it is also preferable to use both in combination. Here, "low-molecular-weight liquid crystalline compound" refers to a liquid crystalline compound that does not have repeating units in its chemical structure. "High-molecular-weight liquid crystalline compound" refers to a liquid crystalline compound that has repeating units in its chemical structure.

[0065] Examples of low-molecular-weight liquid crystalline compounds include the liquid crystalline compounds described in Japanese Patent Publication No. 2013-228706.

[0066] Examples of polymeric liquid crystalline compounds include the thermotropic liquid crystalline polymer described in Japanese Patent Publication No. 2011-237513. Furthermore, from the viewpoint of excellent strength (particularly flexibility) of the light-absorbing anisotropic film, it is preferable that the polymeric liquid crystalline compound has repeating units with crosslinkable groups at its ends. Examples of crosslinkable groups include the polymerizable groups described in paragraphs

[0040] to

[0050] of Japanese Patent Publication No. 2010-244038. Among these, from the viewpoint of improving reactivity and synthetic suitability, acryloyl groups, methacryloyl groups, epoxy groups, oxetanyl groups, and styryl groups are preferred, with acryloyl groups and methacryloyl groups being more preferred.

[0067] When the light-absorbing anisotropic layer contains a polymeric liquid crystalline compound, it is preferable that the polymeric liquid crystalline compound forms a nematic liquid crystal phase. The temperature range in which the nematic liquid crystal phase is observed is preferably room temperature (23°C) to 450°C, and from the viewpoint of handling and manufacturing suitability, 50°C to 400°C is preferred.

[0068] The content of the liquid crystalline compound is preferably 25 to 2000 parts by mass, more preferably 100 to 1300 parts by mass, and even more preferably 200 to 900 parts by mass, based on the content of the dichroic dye compound in the liquid crystal composition. Having the liquid crystalline compound content within the above range further improves the polarizer orientation. The liquid crystalline compound may be present as a single compound or as two or more compounds. If two or more liquid crystalline compounds are present, the content of the liquid crystalline compound refers to the total content of the liquid crystalline compounds.

[0069] For the sake of superior orientation, the liquid crystalline compound is preferably a polymer liquid crystalline compound containing a repeating unit represented by the following formula (1L) (hereinafter also referred to as "repeating unit (1L)").

[0070] [ka]

[0071] In the above formula (1L), P1 represents the repeating main chain, L1 represents a single bond or a divalent linking group, SP1 represents a spacer group, M1 represents a mesogenic group, and T1 represents a terminal group.

[0072] Specifically, the main chain of the repeating unit represented by P1 can be, for example, a group represented by the following formulas (P1-A) to (P1-D), and among these, the group represented by the following formula (P1-A) is preferred from the viewpoint of the diversity of monomers used as raw materials and ease of handling.

[0073] [ka]

[0074] In equations (P1-A) to (P1-D), "*" represents the bond position with L1 in equation (1L). In equations (P1-A) to (P1-D), R 1 , R 2 , R 3 and R 4 Each of these independently represents a hydrogen atom, a halogen atom, a C1-C10 alkyl group, or a C1-C10 alkoxy group. The alkyl group may be a linear or branched alkyl group, or a cyclic alkyl group (cycloalkyl group). The number of carbon atoms in the alkyl group is preferably 1 to 5. The group represented by formula (P1-A) is preferably a unit of the substructure of a poly(meth)acrylic acid ester obtained by polymerization of (meth)acrylic acid esters. The group represented by formula (P1-B) is preferably an ethylene glycol unit formed by ring-opening polymerization of the epoxy group of a compound having an epoxy group. The group represented by formula (P1-C) is preferably a propylene glycol unit formed by ring-opening polymerization of the oxetane group of a compound having an oxetane group. The group represented by formula (P1-D) is preferably a siloxane unit of a polysiloxane obtained by condensation polymerization of a compound having at least one of an alkoxysilyl group and a silanol group. Here, the compound having at least one of an alkoxysilyl group and a silanol group is a compound of formula SiR 4 (OR 5 Examples include compounds having a group represented by )2-. In the formula, R 4 R in (P1-D) 4 It is synonymous with multiple R 5 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

[0075] L1 is a single bond or a divalent linking group. The divalent linking groups represented by L1 include -C(O)O-, -OC(O)-, -O-, -S-, and -C(O)NR 3 -, -NR 3 C(O)-, -SO2-, and -NR 3 R 4 - are some examples. In the formula, R 3 and R 4 Each of these independently represents a C1-C6 alkyl group which may have a hydrogen atom or a substituent W (described later). When P1 is a group represented by formula (P1-A), L1 is preferably a group represented by -C(O)O- because it offers a superior degree of orientation. When P1 is a group represented by formulas (P1-B) to (P1-D), L1 is preferably a single bond because it provides a better degree of orientation.

[0076] The spacer group represented by SP1 preferably includes at least one structure selected from the group consisting of oxyethylene structure, oxypropylene structure, polysiloxane structure, and fluorinated alkylene structure, due to reasons such as its tendency to exhibit liquid crystalline properties and the availability of raw materials. Here, the oxyethylene structure represented by SP1 is *-(CH2-CH2O) n1A base represented by -* is preferred. In the formula, n1 represents an integer from 1 to 20, and * represents the bonding position with L1 or M1 in the above formula (1L). n1 is preferably an integer from 2 to 10, more preferably an integer from 2 to 4, and most preferably 3, because it provides a better degree of orientation. Furthermore, the oxypropylene structure represented by SP1 is *-(CH(CH3)-CH2O) because it has a superior degree of orientation. n2 A base represented by -* is preferred. In the formula, n2 represents an integer from 1 to 3, and * represents the bonding position with L1 or M1. Furthermore, the polysiloxane structure represented by SP1 is *-(Si(CH3)2-O) because it has a better degree of orientation. n3 A base represented by -* is preferred. In the formula, n3 represents an integer between 6 and 10, and * represents the bonding position with L1 or M1. Furthermore, the alkylene fluoride structure represented by SP1 is *-(CF2-CF2) because it has a superior degree of orientation. n4 A base represented by -* is preferred. In the formula, n4 represents an integer between 6 and 10, and * represents the bonding position with L1 or M1.

[0077] The mesogenic group represented by M1 is the group that represents the main skeleton of liquid crystal molecules that contribute to liquid crystal formation. Liquid crystal molecules exhibit liquid crystalline properties, which is an intermediate state (mesophase) between the crystalline state and the isotropic liquid state. There are no particular restrictions on the mesogenic group; for example, refer to the description in "Flussige Kristalle in Tabellen II" (VEB Deutsche Verlag fur Grundstoff Industrie, Leipzig, 1984), especially pages 7 to 16, and the description in the Liquid Crystal Handbook (Maruzen, 2000), edited by the Liquid Crystal Handbook Editorial Committee, especially Chapter 3. As the mesogenic group, a group having at least one cyclic structure selected from the group consisting of aromatic hydrocarbon groups, heterocyclic groups, and alicyclic groups is preferred. The mesogenic group preferably has aromatic hydrocarbon groups, more preferably has 2 to 4 aromatic hydrocarbon groups, and even more preferably has 3 aromatic hydrocarbon groups, because it provides a better degree of orientation.

[0078] As for the mesogenic group, a group represented by the following formula (M1-A) or (M1-B) is preferred, and the group represented by formula (M1-B) is more preferred, from the viewpoint of exhibiting liquid crystalline properties, adjusting the liquid crystal phase transition temperature, availability of raw materials, and suitability for synthesis, as well as because it offers a superior degree of orientation.

[0079] [ka]

[0080] In formula (M1-A), A1 is a divalent group selected from the group consisting of aromatic hydrocarbon groups, heterocyclic groups, and alicyclic groups. These groups may be substituted with alkyl groups, alkyl fluoride groups, alkoxy groups, or substituent W (described later). The divalent group represented by A1 is preferably a 4- to 6-membered ring. Furthermore, the divalent group represented by A1 may be a monoring or a fused ring. * indicates the binding site with SP1 or T1.

[0081] Examples of the divalent aromatic hydrocarbon group represented by A1 include phenylene, naphthylene, fluorene-diyl, anthracene-diyl, and tetracene-diyl groups. From the viewpoint of the diversity of mesogenic skeleton design and the availability of raw materials, a phenylene or naphthylene group is preferred, with a phenylene group being more preferred.

[0082] The divalent heterocyclic group represented by A1 may be either aromatic or non-aromatic, but from the viewpoint of improving the degree of orientation, it is preferable that it be a divalent aromatic heterocyclic group. Atoms other than carbon that constitute a divalent aromatic heterocyclic group include nitrogen, sulfur, and oxygen atoms. If an aromatic heterocyclic group has multiple atoms other than carbon that constitute the ring, these may be the same or different. Specific examples of divalent aromatic heterocyclic groups include, for example, pyridylene (pyridine-diyl group), pyridazine-diyl group, imidazole-diyl group, thienylene (thiophene-diyl group), quinolylene (quinoline-diyl group), isoquinolylene (isoquinoline-diyl group), oxazole-diyl group, thiazole-diyl group, oxadiazole-diyl group, benzothiazole-diyl group, benzothiadiazole-diyl group, phthalimide-diyl group, thienothiazole-diyl group, thiazolothiazole-diyl group, thienothiophene-diyl group, and thienoxazole-diyl group.

[0083] Specific examples of the divalent alicyclic group represented by A1 include the cyclopentylene group and the cyclohexylene group.

[0084] In equation (M1-A), a1 represents an integer between 1 and 10. If a1 is 2 or greater, multiple A1s may be the same or different.

[0085] In formula (M1-B), A2 and A3 are each independently divalent groups selected from the group consisting of aromatic hydrocarbon groups, heterocyclic groups, and alicyclic groups. Specific examples and preferred embodiments of A2 and A3 are the same as those for A1 in formula (M1-A), so their explanation is omitted. In formula (M1-B), a2 represents an integer from 1 to 10. When a2 is 2 or greater, multiple A2s may be the same or different, multiple A3s may be the same or different, and multiple LA1s may be the same or different. a2 is preferably an integer of 2 or greater, and more preferably 2, because it results in a better degree of orientation. In formula (M1-B), when a2 is 1, LA1 is a divalent linking group. When a2 is 2 or more, each of the multiple LA1s is independently either a single bond or a divalent linking group, and at least one of the multiple LA1s is a divalent linking group. When a2 is 2, it is preferable that one of the two LA1s is a divalent linking group and the other is a single bond, for a better degree of orientation.

[0086] In formula (M1-B), the divalent linking group represented by LA1 is -O-, -(CH2) g -,-(CF2) g -, -Si(CH3)2-, -(Si(CH3)2O) g -,-(OSi(CH3)2) g -(g represents 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-, -OC(O)O-, -N(Z)C(O)-, -C(O)N(Z)- , -C(Z)=C(Z')-C(O)O-, -OC(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- Examples include -SC(O)-C(Z)=C(Z')-, -C(Z)=NN=C(Z')- (where Z, Z', and Z'' independently represent hydrogen, a C1-C4 alkyl group, 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-. Among these, -C(O)O- is preferred because it offers superior orientation. LA1 may also be a group formed by combining two or more of these groups.

[0087] An example of M1 is the following structure. In the example below, "Ac" represents an acetyl group.

[0088] [ka]

[0089] [ka]

[0090] Examples of terminal groups represented by T1 include hydrogen atoms, halogen atoms, cyano groups, nitro groups, hydroxyl groups, C1-C10 alkyl groups, C1-C10 alkoxy groups, C1-C10 alkylthio groups, C1-C10 alkoxycarbonyloxy groups, C1-C10 alkoxycarbonyl groups (ROC(O)-: R is an alkyl group), C1-C10 acyloxy groups, C1-C10 acylamino groups, C1-C10 alkoxycarbonylamino groups, C1-C10 sulfonylamino groups, C1-C10 sulfamoyl groups, C1-C10 carbamoyl groups, C1-C10 sulfinyl groups, and C1-C10 ureido groups and (meth)acryloyloxy group-containing groups. Examples of the (meth)acryloyloxy group-containing groups mentioned above include the group represented by -LA (where L represents a single bond or a linking group; specific examples of linking groups are the same as those for L1 and SP1 above; A represents a (meth)acryloyloxy group). For T1, a carbon-1 to carbon-10 alkoxy group is preferred, a carbon-1 to carbon-5 alkoxy group is more preferred, and a methoxy group is even more preferred, due to its superior degree of orientation. These terminal groups may be further substituted with these groups or the crosslinking groups described above. The number of atoms in the main chain of T1 is preferably 1 to 20, more preferably 1 to 15, even more preferably 1 to 10, and particularly preferably 1 to 7, for better orientation. The orientation of the polarizer is further improved when the number of atoms in the main chain of T1 is 20 or less. Here, "main chain" in T1 refers to the longest molecular chain bonded to M1, and hydrogen atoms are not counted in the number of atoms in the main chain of T1. For example, if T1 is an n-butyl group, the number of atoms in the main chain is 4, and if T1 is a sec-butyl group, the number of atoms in the main chain is 3.

[0091] The content is preferably 20 to 100% by mass relative to 100% by mass of the total repeating units of the polymeric liquid crystalline compound, due to the superior degree of orientation. In this invention, the content of each repeating unit in the polymeric liquid crystalline compound is calculated based on the amount (mass) of each monomer used to obtain each repeating unit. The repeating unit (1L) may be present as a single unit or as two or more units in the polymeric liquid crystalline compound. In particular, it is preferable to have two types of repeating units (1L) in the polymeric liquid crystalline compound because it results in a superior degree of orientation.

[0092] When a polymeric liquid crystalline compound contains two types of repeating units (1L), it is preferable that the terminal group represented by T1 in one of the repeating units (repeating unit A) is an alkoxy group, and the terminal group represented by T1 in the other repeating unit (repeating unit B) is a group other than an alkoxy group, in order to obtain a superior degree of orientation. In the repeating unit B described above, the terminal group represented by T1 is preferably an alkoxycarbonyl group, a cyano group, or a (meth)acryloyloxy group-containing group, and more preferably an alkoxycarbonyl group or a cyano group, because it provides a better degree of orientation. The ratio (A / B) of the content of repeating unit A in the polymeric liquid crystalline compound to the content of repeating unit B in the polymeric liquid crystalline compound is preferably 50 / 50 to 95 / 5, more preferably 60 / 40 to 93 / 7, and even more preferably 70 / 30 to 90 / 10, for the reason that it provides a better degree of orientation.

[0093] Furthermore, the polymeric liquid crystalline compound may have repeating units (1L) that do not have a mesogenic group. An example of a repeating unit that does not have a mesogenic group is a repeating unit in formula (1L) where M1 is a single bond. When the polymeric liquid crystalline compound has repeating units that do not have mesogenic groups, the degree of orientation is better, so it is preferable that the amount is greater than 0% by mass and less than or equal to 30% by mass, and more preferably greater than 10% by mass and less than or equal to 20% by mass, relative to 100% by mass of the total repeating units of the polymeric liquid crystalline compound.

[0094] (Weight average molecular weight) The weight-average molecular weight (Mw) of the polymeric liquid crystalline compound is preferably between 1,000 and 500,000, and more preferably between 2,000 and 300,000, due to the superior degree of orientation. If the Mw of the polymeric liquid crystalline compound falls within the above range, the polymeric liquid crystalline compound becomes easier to handle. In particular, from the viewpoint of suppressing cracks during coating, the weight-average molecular weight (Mw) of the polymeric liquid crystalline compound is preferably 10,000 or more, and more preferably between 10,000 and 300,000. Furthermore, from the viewpoint of the temperature latitude of the degree of orientation, the weight-average molecular weight (Mw) of the polymeric liquid crystalline compound is preferably less than 10,000, and preferably between 2,000 and less than 10,000. Here, the weight-average molecular weight and number-average molecular weight in this invention are values ​​measured by gel permeation chromatography (GPC). • Solvent (eluent): N-methylpyrrolidone ·Device name: TOSOH HLC-8220GPC • Column: Three TOSOH TSKgelSuperAWM-H (6mm x 15cm) columns connected together are used. • Column temperature: 25℃ • Sample concentration: 0.1% by mass ·Flow rate: 0.35mL / min • Calibration curve: A calibration curve was used based on 7 samples of TOSOH TSK standard polystyrene with Mw=2,800,000 to 1,050 (Mw / Mn=1.03 to 1.06).

[0095] The substituent W in this specification will be described below. Examples of substituents W include alkyl groups (preferably C1-C20, more preferably C1-C12, and particularly preferably C1-C8 alkyl groups, such as methyl, ethyl, isopropyl, tert-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, and cyclohexyl groups), alkenyl groups (preferably C2-C20, more preferably C2-C12, and particularly preferably C2-C8 alkenyl groups, such as vinyl, aryl, and 2-butenyl groups), Examples include the 3-pentenyl group and the 3-sulfur group), alkynyl groups (preferably alkynyl groups having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms, such as the propargyl group and the 3-pentinyl group), and aryl groups (preferably aryl groups having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 12 carbon atoms, such as the phenyl group, 2,6-diethylphenyl group, 3,5-ditrifluoromethylphenyl group, styryl group, naphthyl group, and biphenyl group). (can be used), substituted or unsubstituted amino groups (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, particularly preferably 0 to 6 carbon atoms, for example, unsubstituted amino groups, methylamino groups, dimethylamino groups, diethylamino groups, and anilino groups), alkoxy groups (preferably having 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, for example, methoxy groups, ethoxy groups, and butoxy groups), oxycarbonyl groups (preferably having 2 to 20 carbon atoms, more preferably 2 to 15 carbon atoms, particularly preferably 2 to 10, for example, a methoxycarbonyl group, an ethoxycarbonyl group, and a phenoxycarbonyl group), an acyloxy group (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, for example, an acetoxy group, a benzoyloxy group, an acryloyl group, and a methacryloyl group), an acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, for example, an acetylamino group and a benzoylamino group),Alkoxycarbonylamino groups (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, for example, methoxycarbonylamino groups), aryloxycarbonylamino groups (preferably having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms, for example, phenyloxycarbonylamino groups), sulfonylamino groups (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, for example, methanesulfonylamino groups) Examples include the phenylsulfamylamino group and the benzenesulfonylamino group), sulfamoyl group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, and particularly preferably 0 to 6 carbon atoms, for example, sulfamoyl group, methylsulfamoyl group, dimethylsulfamoyl group, and phenylsulfamoyl group), carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 1 to 6 carbon atoms, for example, unsubstituted carbamoyl group, methylcarbamoyl group, diethylcarbamoyl group, and phenylsulfamoyl group) Examples include a bamold group, alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 1 to 6 carbon atoms, such as a methylthio group and an ethylthio group), arylthio group (preferably having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, and particularly preferably 6 to 12 carbon atoms, such as a phenylthio group), sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 1 to 6 carbon atoms, such as a mesyl group and a tosyl group). ), sulfinyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, for example, methanesulfinyl group and benzenesulfinyl group), ureido group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, for example, unsubstituted ureido group, methylureido group and phenylureido group), phosphate amide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, for example,Examples include diethyl phosphate amide groups and phenyl phosphate amide groups), hydroxyl groups, mercapto groups, halogen atoms (e.g., fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms), cyano groups, nitro groups, hydroxamic acid groups, sulfino groups, hydrazino groups, imino groups, azo groups, heterocyclic groups (preferably heterocyclic groups having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms, for example heterocyclic groups having heteroatoms such as nitrogen atoms, oxygen atoms, and sulfur atoms, for example epoxy groups, oxy Examples of carbon atoms include cetanyl groups, imidazolyl groups, pyridyl groups, quinolyl groups, furyl groups, piperidyl groups, morpholino groups, maleimide groups, benzoxazolyl groups, benzimidazolyl groups, and benzthiazolyl groups), silyl groups (preferably silyl groups having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, and particularly preferably 3 to 24 carbon atoms, such as trimethylsilyl and triphenylsilyl groups), carboxyl groups, sulfonic acid groups, and phosphate groups.

[0096] The light-absorbing anisotropic layer can be prepared, for example, using a light-absorbing anisotropic layer-forming composition containing the aforementioned dichroic dye compound and any liquid crystalline compound. The light-absorbing anisotropic layer-forming composition may contain components other than dichroic dye compounds and liquid crystalline compounds, such as solvents, vertical alignment agents, interface modifiers, polymerizable components, and polymerization initiators (e.g., radical polymerization initiators).

[0097] <Solvent> From the viewpoint of workability and other factors, compositions for forming light-absorbing anisotropic layers preferably contain a solvent. Examples of solvents include ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, etc.), ethers (e.g., dioxane, tetrahydrofuran, 2-methyltetrahydrofuran, cyclopentyl methyl ether, tetrahydropyran, dioxolane, etc.), aliphatic hydrocarbons (e.g., hexane, etc.), alicyclic hydrocarbons (e.g., cyclohexane, etc.), aromatic hydrocarbons (e.g., benzene, toluene, xylene, trimethylbenzene, etc.), halogenated carbons (e.g., dichloromethane, trichloromethane, dichloroethane, dichlorobenzene, chlorotoluene, etc.), and esters (e.g., acetic acid). Examples of solvents include organic solvents such as methyl, ethyl acetate, butyl acetate, ethyl lactate, etc., alcohols (e.g., ethanol, isopropanol, butanol, cyclohexanol, isopentyl alcohol, neopentyl alcohol, diacetone alcohol, benzyl alcohol, etc.), cellosolves (e.g., methyl cellosolve, ethyl cellosolve, 1,2-dimethoxyethane, etc.), cellosolve acetates, sulfoxides (e.g., dimethyl sulfoxide, etc.), amides (e.g., dimethylformamide, dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone, etc.), and heterocyclic compounds (e.g., pyridine, etc.), as well as water. These solvents may be used individually or in combination of two or more. Of these solvents, ketones (especially cyclopentanone and cyclohexanone), ethers (especially tetrahydrofuran, cyclopentyl methyl ether, tetrahydropyran, and dioxolane), and amides (especially dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and N-ethylpyrrolidone) are preferred. If the light-absorbing anisotropic layer-forming composition contains a solvent, the solvent content is preferably 80 to 99% by mass, more preferably 83 to 98% by mass, and even more preferably 85 to 96% by mass, based on the total mass of the light-absorbing anisotropic layer-forming composition. If two or more solvents are present, the solvent content mentioned above refers to the total content of all solvents.

[0098] <Interface modifier> As the interface modifier, the interface modifier described in the examples section below can be used. When the light-absorbing anisotropic layer-forming composition contains an interface modifier, the content of the interface modifier is preferably 0.001 to 5 parts by mass per 100 parts by mass of the total of the dichroic dye compound and the liquid crystalline compound in the light-absorbing anisotropic layer-forming composition.

[0099] <Polymerizable components> Examples of polymerizable components include compounds containing acrylates (e.g., acrylate monomers). In this case, the light-absorbing anisotropic layer in the present invention contains polyacrylate obtained by polymerizing the above-mentioned acrylate-containing compound. Examples of polymerizable components include the compounds described in paragraph 0058 of Japanese Patent Publication No. 2017-122776. When the light-absorbing anisotropic layer-forming composition contains polymerizable components, the amount of polymerizable components is preferably 3 to 20 parts by mass per 100 parts by mass of the total of the dichroic dye compound and the liquid crystalline compound in the light-absorbing anisotropic layer-forming composition.

[0100] <Vertical Orienting Agent> Examples of vertical orientation agents include boronic acid compounds and onium salts.

[0101] As the boronic acid compound, the compound represented by formula (30) is preferred.

[0102] Formula (30) [ka]

[0103] In formula (30), R1 and R2 each independently represent a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. R3 represents a substituent containing a (meth)acrylic group. Specific examples of boronic acid compounds include the boronic acid compounds represented by general formula (I) described in paragraphs 0023 to 0032 of Japanese Patent Publication No. 2008-225281. The following compounds are also preferred as boronic acid compounds.

[0104] [ka]

[0105] As the onium salt, the compound represented by formula (31) is preferred.

[0106] Formula (31) [ka]

[0107] In formula (31), ring A represents a quaternary ammonium ion consisting of a nitrogen-containing heterocycle. X represents an anion. L1 represents a divalent linking group. L2 represents a single bond or a divalent linking group. Y1 represents a divalent linking group having a 5- or 6-membered ring as a substructure. Z represents a divalent linking group having 2 to 20 alkylene groups as a substructure. P1 and P2 each independently represent a monovalent substituent having a polymerizable ethylenically unsaturated bond. Specific examples of onium salts include the onium salts described in paragraphs 0052 to 0058 of Japanese Patent Publication No. 2012-208397, the onium salts described in paragraphs 0024 to 0055 of Japanese Patent Publication No. 2008-026730, the onium salts described in Japanese Patent Publication No. 2002-37777, and the onium salts described in paragraphs 0153 to 0171 of Japanese Patent Publication No. 2020-076920.

[0108] The content of the vertical alignment agent in the light-absorbing anisotropic layer-forming composition is preferably 0.1 to 400% by mass, and more preferably 0.5 to 350% by mass, relative to the total mass of the liquid crystalline compound. Vertical alignment agents may be used individually or in combination of two or more types. When two or more vertical alignment agents are used, it is preferable that their total amount is within the above range.

[0109] (Leveling agent suitable for vertical orientation) In the case of vertical orientation, it is preferable to include the following leveling agents. When the composition contains leveling agents, planar roughness caused by drying air on the surface of the light-absorbing anisotropic layer is suppressed, and the dichroic dye compounds are oriented more uniformly. The leveling agent is not particularly limited, but a leveling agent containing a fluorine atom (fluorine-based leveling agent) or a leveling agent containing a silicon atom (silicon-based leveling agent) is preferred, and a fluorine-based leveling agent is more preferred.

[0110] Examples of fluorine-based leveling agents include fatty acid esters of polycarboxylic acids in which a portion of the fatty acid is substituted with a fluoroalkyl group, and polyacrylates having fluoro substituents. In particular, when rod-shaped compounds are used as the dichroic dye compound and the liquid crystalline compound, a leveling agent containing repeating units derived from the compound represented by formula (40) is preferred because it promotes the vertical orientation of the dichroic dye compound and the liquid crystalline compound.

[0111] Formula (40) [ka]

[0112] R0 represents a hydrogen atom, a halogen atom, or a methyl group. L represents a divalent linking group. L is preferably an alkylene group having 2 to 16 carbon atoms, and any non-adjacent -CH2- in the alkylene group may be substituted with -O-, -COO-, -CO-, or -CONH-. n represents an integer between 1 and 18.

[0113] A leveling agent having repeating units derived from a compound represented by formula (40) may further contain other repeating units. Other repeating units include those derived from compounds represented by formula (41).

[0114] Formula (41) [ka]

[0115] R11 represents a hydrogen atom, a halogen atom, or a methyl group. X represents an oxygen atom, a sulfur atom, or -N(R13)-. R13 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R12 represents a hydrogen atom, an optionally substituted alkyl group, or an optionally substituted aromatic group. The alkyl group preferably has 1 to 20 carbon atoms. The alkyl group may be linear, branched, or cyclic. Furthermore, examples of substituents that the alkyl group may have include a poly(alkylene oxy) group and a polymerizable group. The definition of a polymerizable group is as described above.

[0116] When the leveling agent contains repeating units derived from the compound represented by formula (40) and repeating units derived from the compound represented by formula (41), the content of the repeating units derived from the compound represented by formula (40) is preferably 10 to 90 mol%, and more preferably 15 to 95 mol%, relative to the total repeating units contained in the leveling agent. When the leveling agent contains repeating units derived from the compound represented by formula (40) and repeating units derived from the compound represented by formula (41), the content of the repeating units derived from the compound represented by formula (41) is preferably 10 to 90 mol%, and more preferably 5 to 85 mol%, relative to the total repeating units contained in the leveling agent.

[0117] Furthermore, as a leveling agent, a leveling agent containing repeating units derived from the compound represented by formula (42) can also be mentioned, instead of the repeating units derived from the compound represented by formula (40) described above.

[0118] Formula (42) [ka]

[0119] R2 represents a hydrogen atom, a halogen atom, or a methyl group. L2 represents a divalent linking group. n represents an integer between 1 and 18.

[0120] Specific examples of leveling agents include the compounds exemplified in paragraphs 0046 to 0052 of Japanese Patent Publication No. 2004-331812, and the compounds described in paragraphs 0038 to 0052 of Japanese Patent Publication No. 2008-257205.

[0121] The leveling agent content in the light-absorbing anisotropic layer-forming composition is preferably 0.001 to 10% by mass, and more preferably 0.01 to 5% by mass, relative to the total mass of the liquid crystalline compound. Leveling agents may be used individually or in combination of two or more types. When two or more leveling agents are used, it is preferable that their total amount is within the above range.

[0122] <Polymerization initiator> The composition for forming a light-absorbing anisotropic layer preferably contains a polymerization initiator. There are no particular restrictions on the polymerization initiator, but it is preferable that it be a photosensitive compound, i.e., a photopolymerization initiator. Various compounds can be used as photopolymerization initiators without particular limitations. Examples of photopolymerization initiators include α-carbonyl compounds (US Patent Nos. 2,367,661 and 2,367,670), acyloin ethers (US Patent No. 2,448,828), α-hydrocarbon-substituted aromatic acyloin compounds (US Patent No. 2,722,512), polynuclear quinone compounds (US Patent Nos. 3,046,127 and 2,951,758), and combinations of triarylimidazole dimers and p-aminophenyl ketones (US Patent No. 3,549,367). Examples include acridine and phenazine compounds (Japanese Patent Publication No. 60-105667 and U.S. Patent No. 4239850), oxadiazole compounds (U.S. Patent No. 4212970), o-acyloxime compounds (Japanese Patent Publication No. 2016-27384

[0065] ), and acylphosphine oxide compounds (Japanese Patent Publication No. 63-40799, Japanese Patent Publication No. 5-29234, Japanese Patent Publication No. 10-95788 and Japanese Patent Publication No. 10-29997). Commercially available photopolymerization initiators can also be used, including BASF's Irgacure-184, Irgacure-907, Irgacure-369, Irgacure-651, Irgacure-819, Irgacure-OXE-01, and Irgacure-OXE-02.

[0123] When the composition for forming a light-absorbing anisotropic layer contains a polymerization initiator, the amount of polymerization initiator is preferably 0.01 to 30 parts by mass, and more preferably 0.1 to 15 parts by mass, based on 100 parts by mass of the total of the dichroic dye compound and the polymeric liquid crystalline compound in the composition for forming a light-absorbing anisotropic layer. A polymerization initiator content of 0.01 parts by mass or more results in good durability of the light-absorbing anisotropic film, and a content of 30 parts by mass or less results in better orientation of the light-absorbing anisotropic film. Polymerization initiators may be used individually or in combination of two or more. When two or more polymerization initiators are included, it is preferable that their total amount is within the above range.

[0124] <Method for forming a light-absorbing anisotropic layer> The method for forming the light-absorbing anisotropic layer is not particularly limited, and examples include a method comprising, in this order, a step of applying the above-mentioned light-absorbing anisotropic layer forming composition to form a coated film (hereinafter also referred to as the "coated film forming step"), and a step of aligning the liquid crystalline components and dichroic dye compounds contained in the coated film (hereinafter also referred to as the "orientation step"). Furthermore, the term "liquid crystallinity component" includes not only the liquid crystallinity compounds mentioned above, but also, if the dichroic dye compounds mentioned above are liquid crystallinity, the liquid crystallinity dichroic dye compounds themselves.

[0125] (Coating film formation process) The coating film formation process involves applying a light-absorbing anisotropic layer-forming composition to form a coating film. By using a light-absorbing anisotropic layer-forming composition containing the aforementioned solvent, or by using a light-absorbing anisotropic layer-forming composition that has been made into a liquid such as a molten liquid by heating or other means, it becomes easier to apply the light-absorbing anisotropic layer-forming composition. Specific examples of known methods for applying the light-absorbing anisotropic layer-forming composition include, for example, roll coating, gravure printing, spin coating, wire bar coating, extrusion coating, direct gravure coating, reverse gravure coating, die coating, spray coating, and inkjet coating.

[0126] (Orientation process) The orientation process is a step in which the liquid crystalline components contained in the coated film are oriented. This results in a light-absorbing anisotropic layer. The orientation step may include a drying process. The drying process can remove components such as solvents from the coating film. The drying process may be carried out by leaving the coating film at room temperature for a predetermined time (e.g., natural drying), or by heating and / or blowing air. Here, the liquid crystalline components contained in the light-absorbing anisotropic layer-forming composition may be oriented by the coating film formation process or drying treatment described above. For example, in embodiments in which the light-absorbing anisotropic layer-forming composition is prepared as a coating solution containing a solvent, a coating film with light-absorbing anisotropy (i.e., a light-absorbing anisotropic film) is obtained by drying the coating film to remove the solvent from the coating film. If the drying process is carried out at a temperature above the transition temperature of the liquid crystalline components in the coated film to the liquid crystal phase, the heat treatment described later may not be necessary.

[0127] The transition temperature of the liquid crystalline component in the coated film to the liquid crystal phase is preferably 10 to 250°C, and more preferably 25 to 190°C, from the viewpoint of manufacturing suitability. A transition temperature of 10°C or higher is preferable because it eliminates the need for cooling treatment to lower the temperature to the temperature range in which the liquid crystal phase is observed. Furthermore, a transition temperature of 250°C or lower is preferable because it eliminates the need for high temperatures even when creating an isotropic liquid state at a temperature higher than the temperature range in which the liquid crystal phase is observed, thereby reducing the waste of thermal energy and the deformation and deterioration of the substrate.

[0128] The orientation step preferably includes a heat treatment. This allows the liquid crystalline components contained in the coated film to be oriented, making the coated film after heat treatment suitable for use as a light-absorbing anisotropic film. For heat treatment, a temperature of 10 to 250°C is preferred, and 25 to 190°C is more preferred, from the standpoint of suitability for manufacturing. The heating time is preferably 1 to 300 seconds, and 1 to 60 seconds is more preferred.

[0129] The orientation step may include a cooling process performed after the heat treatment. The cooling process involves cooling the heated coating film to room temperature (approximately 20-25°C). This fixes the orientation of the liquid crystalline components contained in the coating film. The cooling method is not particularly limited and can be carried out by known methods. By following the above steps, a light-absorbing anisotropic film can be obtained. In this embodiment, drying treatment and heat treatment are mentioned as methods for aligning the liquid crystalline components contained in the coating film, but the method is not limited to these, and can be carried out by known orientation treatments.

[0130] (Other processes) The method for forming a light-absorbing anisotropic layer may include a step of curing the light-absorbing anisotropic layer after the orientation step (hereinafter also referred to as the "curing step"). The curing process is carried out by heating and / or light irradiation (exposure), for example, if the light-absorbing anisotropic layer has crosslinkable groups (polymerizable groups). Among these, it is preferable that the curing process be carried out by light irradiation. Various light sources can be used for curing, such as infrared light, visible light, or ultraviolet light, but ultraviolet light is preferred. Furthermore, ultraviolet light may be irradiated while heating during curing, or ultraviolet light may be irradiated through a filter that transmits only specific wavelengths. When exposure is performed while heating, the heating temperature during exposure is preferably 25 to 140°C, although this also depends on the transition temperature of the liquid crystalline components in the liquid crystal film to the liquid crystal phase. Furthermore, exposure may be performed under a nitrogen atmosphere. When the curing of the liquid crystal film progresses by radical polymerization, exposure under a nitrogen atmosphere is preferable because it reduces the inhibition of polymerization by oxygen.

[0131] The thickness of the light-absorbing anisotropic layer is not particularly limited, but from the viewpoint of flexibility when the laminate of the present invention, described later, is used as a polarizing element, it is preferably 100 to 8000 nm, and more preferably 300 to 5000 nm.

[0132] [Transparent base film] The optical film of the present invention may have a transparent substrate film. The transparent substrate film is preferably positioned on the side of the light-absorbing anisotropic layer opposite to the side on which the optical film is provided. As the transparent substrate film, known transparent resin films, transparent resin plates, transparent resin sheets, etc., can be used, and there are no particular limitations. As transparent resin films, cellulose acylate films (e.g., cellulose triacetate film (refractive index 1.48), cellulose diacetate film, cellulose acetate butyrate film, cellulose acetate propionate film), polyethylene terephthalate film, polyethersulfone film, polyacrylic resin film, polyurethane resin film, polyester film, polycarbonate film, polysulfone film, polyether film, polymethylpentene film, polyetherketone film, (meth)acrylonitrile film, etc. can be used.

[0133] Among these, cellulose acylate film is preferred because it has high transparency, low optical birefringence, is easy to manufacture, and is commonly used as a protective film for polarizing plates, and cellulose triacetate film is particularly preferred. The thickness of the transparent substrate film is typically between 20 μm and 100 μm. In the present invention, it is particularly preferable that the transparent substrate film is a cellulose ester film and has a film thickness of 20 to 70 μm.

[0134] [Orientation film] The optical film of the present invention may have an alignment layer between the transparent substrate film and the light-absorbing anisotropic layer. The orientation layer can be any layer as long as it can position the dichroic dye compound in the desired orientation state on the orientation layer. For example, a film formed from a polyfunctional acrylate compound or polyvinyl alcohol may be used. Polyvinyl alcohol is particularly preferred.

[0135] [Barrier layer] The optical film of the present invention preferably has a barrier layer along with a light-absorbing anisotropic layer. Here, the barrier layer is also called a gas barrier layer (oxygen barrier layer) and has the function of protecting the polarizing element of the present invention from gases such as oxygen in the atmosphere, moisture, or compounds contained in adjacent layers. For information regarding the barrier layer, see, for example, paragraphs

[0014] to

[0054] of Japanese Patent Publication No. 2014-159124, paragraphs

[0042] to

[0075] of Japanese Patent Publication No. 2017-121721, paragraphs

[0045] to

[0054] of Japanese Patent Publication No. 2017-115076, paragraphs

[0010] to

[0061] of Japanese Patent Publication No. 2012-213938, and paragraphs

[0021] to

[0031] of Japanese Patent Publication No. 2005-169994.

[0136] [Refractive index adjustment layer] The optical film of the present invention preferably has a refractive index adjustment layer in order to suppress internal reflection caused by the high refractive index of the light absorption anisotropy layer. The refractive index adjustment layer is a layer arranged in contact with the light absorption anisotropy layer, and its in-plane average refractive index at a wavelength of 550 nm is 1.55 or more and 1.70 or less. It is preferable that the refractive index adjustment layer is for so-called index matching.

[0137] [Color adjustment layer] The optical film of the present invention preferably has a color adjustment layer containing at least one dye compound. The dye compound contained in the color adjustment layer is preferably in an unoriented state. When the amount of dye in the light absorption anisotropy layer is adjusted, the change in color when viewed from oblique directions relative to the transmittance center axis becomes larger. However, by adjusting the color using a color adjustment layer, the change in color when viewed from oblique directions relative to the change in color along the transmittance center axis can be suppressed. This color adjustment layer may have only the function of a color adjustment layer on its own, or it may have functions integrated with other layers.

[0138] The absorption peak wavelength of the dye compound contained in the color adjustment layer is preferably between 500 nm and 650 nm, and more preferably between 550 nm and 600 nm. By setting the absorption of the dye compound within this range, the color of the optical film in the present invention can be adjusted to be more neutral.

[0139] Examples of dye compounds included in the color adjustment layer include azo, methine, anthraquinone, triarylmethane, oxazine, azomethine, phthalocyanine, porphyrin, perylene, pyrrolopyrrole, and squarylium. However, azo, phthalocyanine, and anthraquinone are preferred from the viewpoint of excellent absorption waveform, heat resistance, and light resistance, with anthraquinone being particularly preferred. Examples include the dye compounds described in "Functional Dyes" by Shin Okawara, Ken Matsuoka, Tsuneaki Hirashima, and Teijiro Kitao, Kodansha, 1992, and "Electronics-Related Materials" supervised by Sumio Tokita, CMC Co., Ltd., 1998.

[0140] The following are specific examples of dye compounds used in the present invention, but the present invention is not limited to these.

[0141] Anthraquinone [ka]

[0142] Azo [ka]

[0143] Triarylmethane [ka]

[0144] Oxazine [ka]

[0145] Phthalocyanine [ka]

[0146] [Method for manufacturing optical films] An example of a method for manufacturing the optical film of the present invention is a method comprising, in this order, the steps of: applying an alignment film-forming composition onto the transparent substrate film to form an alignment film; and applying the light-absorbing anisotropy layer-forming composition onto the alignment film to orient the dichroic dye compound contained in the coated film and obtain the light-absorbing anisotropy layer. Each step can be carried out according to known methods, and is not particularly limited.

[0147] [Electroluminescent display device] The electroluminescent (EL) display device of the present invention is an EL display device in which the optical film of the present invention described above is laminated on an EL substrate having multiple colors of light-emitting elements made of EL. Furthermore, the EL display device of the present invention is preferably a self-emissive display device that utilizes an inorganic EL light-emitting element. Furthermore, it is preferable that the EL display device of the present invention uses a light-emitting diode (LED) as the light-emitting element.

[0148] [EL substrate] In the present invention, various known EL substrates used in self-emissive display devices using inorganic EL light-emitting elements can be used as the EL substrate. Similar to known EL substrates, the EL substrate has a large number of R light-emitting elements, G light-emitting elements, and B light-emitting elements arranged in two dimensions.

[0149] In one embodiment, the EL substrate may be a transparent substrate. Preferably, inorganic EL light-emitting elements may be arranged on a transparent substrate. By using a transparent substrate, a display device with a highly aesthetic design can be realized in which the background of the display device is visible and the reflection of ambient light on the substrate surface is suppressed.

[0150] In the present invention, when the light-emitting element is a light-emitting diode (LED), it is preferable that the LED has three colors: red, green, and blue, and that when the luminances at 460 nm, 530 nm, and 630 nm in the normal direction of the electroluminescent display device are defined as Lb, Lg, and Lr, respectively, both of the following relationships (3) and (4) are satisfied. 3 ≤ Lg / Lb ≤ 8 (3) 0.5 ≤ Lr / Lb ≤ 2.5 (4) Here, the "luminance at 460nm, 530nm, and 630nm in the normal direction of the electroluminescent display device" can be measured, for example, by a Topcon SR-UL1R spectroradiometer. [Examples]

[0151] The present invention will be specifically described below based on examples. The materials, reagents, amounts and proportions of substances, and procedures shown in the following examples can be modified as appropriate, as long as they do not depart from the spirit of the present invention. Therefore, the present invention is not limited to the following examples.

[0152] [Example 1] <Formation of orientation film> The surface of a cellulose acylate film (TAC substrate with a thickness of 40 μm; TG40, Fujifilm Corporation) was saponified with an alkaline solution, and an alignment film-forming composition was applied thereon using a wire bar. The support with the coated film was dried with 60°C hot air for 60 seconds, and then with 100°C hot air for 120 seconds to form an alignment film AL1, and an alignment film-coated TAC film 1 was obtained. The film thickness was 1 μm.

[0153] ------------------------------------------------------------------ (Composition for forming alignment film 1) ------------------------------------------------------------------ Modified polyvinyl alcohol PVA-1 3.80 parts by mass ·IRGACURE2959 0.20 parts by mass ·Water 70 parts by mass • Methanol 30 parts by mass ―――――――――――――――――――――――――――――――――

[0154] Modified polyvinyl alcohol PVA-1

Chemical Formula

[0155] <Formation of light absorption anisotropic layer P1> The following composition P1 for forming a light absorption anisotropic layer was continuously applied onto the obtained alignment film AL1 using a wire bar, heated at 120°C for 60 seconds, and then cooled to room temperature (23°C). Subsequently, the resultant was heated at 80°C for 60 seconds and cooled to room temperature again. Thereafter, using an LED lamp (central wavelength: 365 nm) with an illuminance of 200 mW / cm 2 under the irradiation condition of , irradiation was performed for 2 seconds, thereby forming a light absorption anisotropic layer P1 on the alignment film 1. The film thickness of the light absorption anisotropic layer P1 was 3.5 μm.

[0156] ――――――――――――――――――――――――――――――――― Composition of composition P1 for forming light absorption anisotropic layer ――――――――――――――――――――――――――――――――― ·The following dichroic dye compound D-1: 0.63 parts by mass ·The following dichroic dye compound D-2: 0.85 parts by mass ·The following polymer liquid crystalline compound P-1: 8.63 parts by mass ·IRGACUREOXE-02 (manufactured by BASF): 0.16 parts by mass ·The following compound E-1: 0.13 parts by mass ·The following compound E-2: 0.13 parts by mass ·The following surfactant F-1: 0.004 parts by mass ·Cyclopentanone: 80.53 parts by mass ·Benzyl alcohol: 8.95 parts by mass ―――――――――――――――――――――――――――――――――

[0157] Dichroic dye compound D-1

Chem

[0158] Dichroic dye compound D-2

Chem

[0159] Polymeric liquid crystalline compound P-1

Chem

[0160] Compound E-1

Chem

[0161] Compound E-2

Chem

[0162] Surfactant F-1

Chem

[0163] <Formation of oxygen blocking layer B1> On the formed light absorption anisotropic layer P1, a coating liquid of the following composition (composition B1 for forming an oxygen blocking layer) was continuously applied using a wire bar. Thereafter, drying was performed with hot air at 100°C for 2 minutes, thereby forming a polyvinyl alcohol (PVA) alignment layer (oxygen blocking layer B1) having a thickness of 0.5 μm on the light absorption anisotropic layer P1.

[0164] In this way, optical film 1 was obtained, which comprises a cellulose acylate film, an alignment film AL1, a light absorption anisotropic layer P1, and an oxygen blocking layer B1 adjacently provided in this order.

[0165] ------------------------------------------------------------------ Composition of oxygen barrier layer forming composition B1 ------------------------------------------------------------------ • 3.80 parts by mass of the following modified polyvinyl alcohol • Polymerization initiator IRGACURE2959 (BASF) 0.20 parts by mass ·Water 70 parts by mass • Methanol 30 parts by mass ------------------------------------------------------------------

[0166] Modified polyvinyl alcohol [ka]

[0167] [Example 2] Optical film 2 was prepared in the same manner as in Example 1, except that dichroic dye compound D-2 was replaced with dichroic dye compound D-3 described below.

[0168] Dichroic dye compound D-3 [ka]

[0169] [Example 3] Optical film 3 was prepared in the same manner as in Example 1, except that dichroic dye compound D-2 was replaced with dichroic dye compound D-4.

[0170] Dichroic dye compound D-4 [ka]

[0171] [Comparative Example 1] Optical film 4 was prepared in the same manner as in Example 1, except that dichroic dye compound D-2 was replaced with dichroic dye compound D-5.

[0172] Dichroic dye compound D-5 [ka]

[0173] [Comparative Example 2] An optical film 5 was prepared in the same manner as in Example 1, except that the composition of the light-absorbing anisotropic layer P1 was changed to the composition of P5 described below.

[0174] ------------------------------------------------------------------ Composition of composition P5 for forming a light-absorbing anisotropic layer ------------------------------------------------------------------ • 0.63 parts by mass of the above dichroic dye compound D-1 • 0.17 parts by mass of the above dichroic dye compound D-3 • 9.31 parts by mass of the above polymeric liquid crystalline compound P-1 • IRGACUREOXE-02 (BASF) 0.16 parts by mass • Compound E-1: 0.13 parts by mass • 0.13 parts by mass of the above compound E-2 • 0.004 parts by mass of the above surfactant F-1 Cyclopentanone 80.53 parts by mass Benzyl alcohol 8.95 parts by mass ------------------------------------------------------------------

[0175] [Example 4] An optical film 6 was prepared in the same manner as in Example 1, except that the composition of the light-absorbing anisotropic layer P1 was changed to the composition of P6 described below.

[0176] ------------------------------------------------------------------ Composition of composition P6 for forming a light-absorbing anisotropic layer ------------------------------------------------------------------ • 0.80 parts by mass of the following dichroic dye compound D-6 • 9.31 parts by mass of the above polymeric liquid crystalline compound P-1 • IRGACUREOXE-02 (BASF) 0.16 parts by mass • Compound E-1: 0.13 parts by mass • 0.13 parts by mass of the above compound E-2 • 0.004 parts by mass of the above surfactant F-1 Cyclopentanone 80.53 parts by mass Benzyl alcohol 8.95 parts by mass ------------------------------------------------------------------

[0177] Dichroic dye compound D-6 [ka]

[0178] [Example 5] An optical film 7 was prepared in the same manner as in Example 1, except that the composition of the light-absorbing anisotropic layer P1 was changed to the composition of P7 described below.

[0179] ------------------------------------------------------------------ Composition of composition P7 for forming a light-absorbing anisotropic layer ------------------------------------------------------------------ • 0.50 parts by mass of the above dichroic dye compound D-1 • 0.68 parts by mass of the above dichroic dye compound D-2 • 0.30 parts by mass of the above dichroic dye compound D-6 • 8.63 parts by mass of the above polymeric liquid crystalline compound P-1 • IRGACUREOXE-02 (BASF) 0.16 parts by mass • Compound E-1: 0.13 parts by mass • 0.13 parts by mass of the above compound E-2 • 0.004 parts by mass of the above surfactant F-1 Cyclopentanone 80.53 parts by mass Benzyl alcohol 8.95 parts by mass ------------------------------------------------------------------

[0180] [Comparative Example 3] An optical film 8 was prepared in the same manner as in Example 5, except that dichroic dye compound D-6 was replaced with dichroic dye compound D-7.

[0181] Dichroic dye compound D-7 [ka]

[0182] [Performance evaluation] [Transmittance] The transmittances (Tb, Tg, and Tr) of the obtained optical film were measured at 460 nm, 530 nm, and 630 nm in a direction 45° from the film normal using the method described above. The calculated results for Tb / Tr and Tg / Tr are shown in Table 1 below. Furthermore, the transmittance (front transmittance) at 460 nm, 530 nm, and 630 nm in the direction normal to the film was measured for the obtained optical film using the method described above.

[0183] [45° Color Evaluation] A micro-LED was fabricated based on Non-Patent Document 1. The brightness of the fabricated micro-LED at 460nm, 530nm, and 630nm, both in the front and at a 45° angle, was measured using a Topcon SR-UL1R spectroradiometer. As a result, when the front was displayed in white, Lg / Lb = 6.5 and Lr / Lb = 1.8. Furthermore, when the front was adjusted to display white, a color shift occurred in the 45° direction. When the luminance at 460nm, 530nm, and 630nm in the 45° direction was denoted as Lb(45), Lg(45), and Lr(45), respectively, Lg(45) / Lb(45) = 4.8 and Lr(45) / Lb(45) = 0.6. In this case, the luminance in the 45° direction was calculated using the average value of the four directional angles of the panel (up, down, left, and right). Next, the optical film obtained above was placed on the top surface of the fabricated micro-LED, and adjustments were made again so that the front was white. After that, the color was checked from a 45° direction, and the evaluation was performed as follows. A: Neutral with no color shift B: Slight color shift is visible, but it is almost neutral. C: Color shift is observed; it is not neutral.

[0184] [Orientation degree] The degree of orientation of the obtained optically absorbed anisotropic layer at a wavelength of 530 nm was measured using the method described above.

[0185] The evaluation results are shown in Table 1 below. Note that the percentages in Table 1 represent the ratio of each dichroic dye compound when the total solid content is set to 100%. [Table 1]

[0186] The results shown in Table 1 indicate that when the degree of orientation of the light-absorbing anisotropic layer is less than 0.7, and the optical film does not satisfy the above-mentioned equations (1) and (2), the transmittance on the front decreases, and the color change in the oblique direction relative to the front cannot be suppressed (Comparative Example 1). Furthermore, it was found that even if the degree of orientation of the light-absorbing anisotropic layer is 0.7 or higher, if the optical film does not satisfy at least one of the above-mentioned equations (1) and (2), color changes in the oblique direction relative to the front cannot be suppressed (Comparative Examples 2 and 3). In contrast, it was found that when the degree of orientation of the light-absorbing anisotropic layer is 0.7 or higher, and the optical film satisfies both of the above-mentioned equations (1) and (2), the decrease in transmittance at the front can be suppressed, and the change in color at an oblique angle to the front can be suppressed (Examples 1-5).

Claims

1. An electroluminescent display device comprising an optical film laminated on an electroluminescent substrate having multiple colors of light-emitting elements produced by electroluminescence, The light-emitting element is a light-emitting diode, When the light-emitting diode has three colors, red, green, and blue, and the luminances at 460 nm, 530 nm, and 630 nm in the normal direction of the electroluminescent display device are defined as Lb, Lg, and Lr, respectively, the following relationships (3) and (4) are both satisfied. 3 ≤ Lg / Lb ≤ 8 (3) 0.5 ≤ Lr / Lb ≤ 2.5 (4) The optical film is an optical film having a light-absorbing anisotropic layer containing a dichroic dye compound. The aforementioned light-absorbing anisotropic layer has an absorption axis in the direction normal to the film, and its degree of orientation at 530 nm is 0.7 or higher. The optical film has a transmittance of 50% or more at 530 nm in the direction normal to the film. An electroluminescent display device in which the optical film satisfies both of the following relationships (1) and (2), when the transmittances at 460 nm, 530 nm, and 630 nm in a direction 45° with respect to the film normal are defined as Tb, Tg, and Tr, respectively. 0.1 ≤ Tb / Tr ≤ 0.5 (1) 0.2 ≤ Tg / Tr ≤ 0.6 (2)

2. The electroluminescent display device according to claim 1, wherein the optical film satisfies both of the following relationships (1-2) and (2-2), when the transmittances of the optical film at 460 nm, 530 nm, and 630 nm in a direction 45° with respect to the film normal are defined as Tb, Tg, and Tr, respectively. 0.2 ≤ Tb / Tr ≤ 0.4 (1-2) 0.3 ≤ Tg / Tr ≤ 0.5 (2-2)

3. The electroluminescent display device according to claim 1 or 2, wherein the light-absorbing anisotropic layer contains two or more types of dichroic dye compounds.

4. The electroluminescent display device according to claim 1 or 2, wherein the light-absorbing anisotropic layer contains a dichroic dye compound having an absorption peak between 430 nm and 500 nm, and a dichroic dye compound having an absorption peak between 500 nm and 560 nm.

5. An electroluminescent display device according to any one of claims 1 to 4, wherein the transmittance at 530 nm in the direction normal to the film is 70% or more.

6. An electroluminescent display device according to any one of claims 1 to 5, wherein the transmittance at 630 nm in the direction normal to the film is 75% or more.

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