Light absorption anisotropic film and laminate

Abstract

The present invention addresses the problem of providing: a light absorption anisotropic film having a low haze value and a high degree of alignment; and a laminate having the same. The light absorption anisotropic film according to the present invention contains a dichroic substance and a matrix comprising all components other than the dichroic substance. When the film is subjected to differential scanning calorimetry, at least one endothermic peak derived from the dichroic substance is observed, and all of the endothermic peaks have endothermic initiation temperature of 105°C or higher.

Description

Optically absorbing anisotropic film and laminate

[0001] The present invention relates to an optically absorptive anisotropic film and a laminate.

[0002]

[0003] A technique for preventing viewing of an image display device and controlling the viewing angle by using a light-absorbing anisotropic film having an absorption axis in the thickness direction is known. For example, Patent Document 1 describes "an optical film having a light-absorbing anisotropic layer containing a liquid crystal compound and a dichroic substance, wherein the angle θ between the transmittance central axis of the light-absorbing anisotropic layer and the normal direction to the surface of the light-absorbing anisotropic layer is 0° or more and 45° or less, and the haze value of the optical film is more than 1% and 20% or less."

[0003] International Publication No. 2022 / 270466

[0004] The present inventors have examined the optically absorbing anisotropic layer (optically absorbing anisotropic film) of the optical film described in Patent Document 1 and have found that the haze value is high and there is room for improvement in the degree of orientation.

[0005] Therefore, an object of the present invention is to provide an optically absorptive anisotropic film having a low haze value and a high degree of orientation, and a laminate having the same.

[0006] As a result of intensive research to achieve the above object, the present inventors have found that an optically absorptive anisotropic film in which at least one endothermic peak derived from a dichroic substance is observed by differential scanning calorimetry (hereinafter also referred to as "DSC," an abbreviation for Differential Scanning Calorimetry), and in which all of the observed endothermic peaks have endothermic onset temperatures of 105°C or higher, has a low haze value and a high degree of orientation, and have completed the present invention. That is, the present inventors have found that the above object can be achieved by the following configuration.

[0007] [1] An optically absorptive anisotropic film containing a dichroic substance and a matrix consisting of all components other than the dichroic substance, wherein at least one endothermic peak attributed to the dichroic substance is observed by differential scanning calorimetry, and all of the endothermic peaks have an endothermic onset temperature of 105°C or higher. Here, the endothermic onset temperature refers to a temperature at which a heat flow of 6% is observed, when the heat flow at the peak top of the endothermic peak is taken as 100%, in a differential scanning calorimetry curve with heat flow on the vertical axis and temperature on the horizontal axis, and which is lower than the temperature at the peak top of the endothermic peak. [2] The optically absorptive anisotropic film according to [1], wherein at least one endothermic peak attributed to the matrix is ​​observed by differential scanning calorimetry, and the peak top of the endothermic peak showing the largest heat flow among the endothermic peaks is observed in a temperature range of 108°C or higher. [3] The optically absorptive anisotropic film according to [1] or [2], wherein the absolute value of the difference between the log P value of the dichroic substance and the log P value of the matrix is ​​4.8 to 5.6. [4] The optically absorptive anisotropic film according to any one of [1] to [3], wherein the angle θ between the central axis of transmittance of the optically absorptive anisotropic film and the normal direction to the surface of the optically absorptive anisotropic film is 0° or more and 45° or less. [5] The optically absorptive anisotropic film according to any one of [1] to [4], wherein the dichroic substance is a mixture containing at least a dye compound having an absorption maximum in the wavelength range of 380 nm to less than 455 nm, a dye compound having an absorption maximum in the wavelength range of 455 nm to less than 560 nm, and a dye compound having an absorption maximum in the wavelength range of 560 nm to 700 nm. [6] A laminate comprising the optically absorptive anisotropic film according to any one of [1] to [5].

[0008] According to the present invention, it is possible to provide an optically absorptive anisotropic film having a low haze value and a high degree of orientation, and a laminate having the same.

[0009] FIG. 1 is a schematic diagram showing an example of a head-mounted display having a laminate of the present invention (hereinafter also abbreviated as "head-mounted display of the present invention"). FIG. 2 is a schematic diagram showing an example of the configuration of a light guide plate for AR (Augmented Reality) glasses. FIG. 3 is a schematic diagram showing a plan view of an evaluation system for the head-mounted display of the present invention. FIG. 4 shows a DSC curve of the optically absorptive anisotropic film prepared in Example 1. FIG. 5 shows a DSC curve of the optically absorptive anisotropic film prepared in Comparative Example 1. FIG. 6 shows a DSC curve of only the matrix contained in the optically absorptive anisotropic films prepared in Example 1 and Comparative Example 1.

[0010] The present invention will be described in detail below. The following description of the constituent elements may be based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the upper and lower limits. In this specification, the upper or lower limit of a numerical range described in a stepwise manner may be replaced with the upper or lower limit of another stepwise manner. In this specification, the upper or lower limit of a numerical range described in a stepwise manner may be replaced with a value shown in the Examples. In this specification, each component may be a single substance corresponding to the component, or two or more substances may be used in combination. When two or more substances are used in combination for each component, the content of that component refers to the total content of the substances used in combination, unless otherwise specified. In addition, in this specification, "(meth)acrylate" is a notation representing "acrylate" or "methacrylate", "(meth)acrylic" is a notation representing "acrylic" or "methacrylic", and "(meth)acryloyl" is a notation representing "acryloyl" or "methacryloyl".

[0011] [Light-absorbing anisotropic film] The light-absorbing anisotropic film of the present invention is a light-absorbing anisotropic film containing a dichroic substance and a matrix consisting of all components other than the dichroic substance. The light-absorbing anisotropic film of the present invention is also a light-absorbing anisotropic film in which at least one endothermic peak derived from the dichroic substance is observed by differential scanning calorimetry, and all of the observed endothermic peaks derived from the dichroic substance (when only one endothermic peak is observed, the observed one endothermic peak) are endothermic peaks with endothermic onset temperatures of 105°C or higher.

[0012] Here, differential scanning calorimetry is performed using a differential scanning calorimeter (e.g., X-DSC7000 manufactured by Seiko Instruments Inc.), by placing a 3.0 mg±0.3 mg sample of the optically absorptive anisotropic film in an aluminum sample pan and measuring the temperature in a nitrogen atmosphere while raising the temperature from room temperature to 140° C. at a rate of 5° C. / min. The endothermic onset temperature is a temperature at which a heat flow of 6% is observed when the heat flow at the endothermic peak top is taken as 100% in a differential scanning calorimetry curve (hereinafter referred to as a "DSC curve") in which the vertical axis represents heat flow (hereinafter referred to as "heat flow" in FIGS. 4 to 6) and the horizontal axis represents temperature, and is lower than the temperature at the endothermic peak top. Specifically, as shown in FIG. 4, in Example 1 described later, when the heat flow at the peak top of the endothermic peak is taken as 100%, the temperature at which a heat flow of 6% is shown is 108°C. However, as shown in FIG. 5, in Comparative Example 1 described later, when the heat flow at the peak top of the endothermic peak is taken as 100%, the temperature at which a heat flow of 6% is shown is 101°C.

[0013] In the present invention, an optically absorptive anisotropic film in which endothermic peaks originating from a dichroic substance are observed by DSC and in which all of the observed endothermic peaks have endothermic onset temperatures of 105°C or higher exhibits a low haze value and a high degree of orientation. The reason for this effect is unclear in detail, but the inventors speculate as follows. First, in an optically absorptive anisotropic film, the dichroic substance is thought to form various aggregates (e.g., crystals, co-crystals, aggregates, etc.). Therefore, the endothermic onset temperature of the endothermic peak originating from the dichroic substance corresponds to the endothermic heat of the most unstable aggregate, and a high endothermic onset temperature indicates that even the most unstable aggregate is relatively stable. It can be said that high stability can be used as an indicator of the strength of the attractive force between dichroic substances and the regularity of their orientation. Therefore, it is thought that an optically absorbing anisotropic film in which the endothermic onset temperatures of all endothermic peaks derived from the dichroic substance are 105°C or higher will have a high degree of orientation, and will have a low haze value because ideal microcrystals are easily formed and there are fewer coarse particles.

[0014] As described above, in the optically absorptive anisotropic film of the present invention, the endothermic onset temperatures of all endothermic peaks derived from the dichroic substance are 105°C or higher, preferably 108°C or higher, and the upper limit of the endothermic onset temperatures is preferably 140°C or lower.

[0015] For the reason that the haze value is lower, the optically absorptive anisotropic film of the present invention is preferably an optically absorptive anisotropic film in which at least one endothermic peak derived from the matrix is ​​observed by DSC, and the peak top (hereinafter also referred to as the "maximum endothermic peak temperature of the matrix") of the endothermic peak exhibiting the maximum heat flow among these endothermic peaks (i.e., when multiple endothermic peaks are observed, this refers to the endothermic peak exhibiting the maximum heat flow among all endothermic peaks, and when only one endothermic peak is observed, this refers to the observed single endothermic peak) is observed in a temperature range of 108°C or higher, more preferably in a temperature range of 109°C or higher. The upper limit of this temperature range is preferably 140°C or lower.

[0016] Here, whether the observed endothermic peak is due to the dichroic substance or the matrix can be determined as follows. First, when each material constituting the optically absorptive anisotropic film is available, as in the examples described below, a film made of materials other than the dichroic substance, i.e., a film made only of the matrix, is prepared, and DSC of the film is measured. The DSC results are compared with the DSC results of an optically absorptive anisotropic film containing the dichroic substance and the matrix, thereby enabling the endothermic peak of the matrix and the endothermic peak of the dichroic substance to be distinguished. Furthermore, when the endothermic peak of the matrix overlaps with the endothermic peak of the dichroic substance, a separate matrix having an endothermic peak sufficiently lower than that of the dichroic substance (the endothermic peaks do not overlap) is prepared, and an optically absorptive anisotropic film made of the matrix and the dichroic substance is prepared, and the endothermic peak of the dichroic substance can be measured. On the other hand, if only the optically absorptive anisotropic film is available, the optically absorptive anisotropic film is crushed as finely as possible, and then the dichroic substance is extracted and removed using a solvent or the like. The optically absorptive anisotropic film is prepared from the sample, and the powder of the matrix alone that remains unextracted is subjected to DSC measurement. By comparing these results with the DSC measurement results of the optically absorptive anisotropic film before extraction (i.e., as obtained), the endothermic peaks of the matrix and the dichroic substance can be distinguished from each other. Furthermore, as in the above case, if the endothermic peaks of the matrix and the dichroic substance overlap, a separate matrix with an endothermic peak sufficiently lower than that of the dichroic substance can be prepared, and an optically absorptive anisotropic film consisting of this matrix and the dichroic substance obtained by the above extraction can be prepared, and the endothermic peak of the dichroic substance can be measured. Alternatively, the molecular structure of the dye obtained by extraction may be identified by known means such as nuclear magnetic resonance (NMR), infrared absorption spectrometry (IR), and mass spectrometry, and a dichroic substance having the same molecular structure may be synthesized, combined with a matrix to prepare an optical absorption anisotropic film, and the endothermic peak may be measured by DSC.

[0017] In the optically absorptive anisotropic film of the present invention, the absolute value of the difference between the log P value of the dichroic material and the log P value of the matrix (hereinafter also abbreviated as "Δlog P value") is preferably 4.8 to 5.8, because this results in a higher degree of orientation. Here, the log P value is an index that expresses the hydrophilic and hydrophobic properties of a chemical structure and is sometimes referred to as the hydrophilic-hydrophobic parameter. The log P value can be calculated using software such as ChemBioDraw Ultra or HSPiP (Ver. 4.1.07). It can also be experimentally determined using the method of OECD Guidelines for the Testing of Chemicals, Section 1, Test No. 117, for example. In the present invention, unless otherwise specified, the log P value is calculated by inputting the structural formula of a compound into HSPiP (Ver. 4.1.07). The log P value of the matrix can be calculated by calculating the log P value for each component other than the dichroic visualizing substance and then calculating a weighted average based on the mass-based addition ratio. When a low molecular weight liquid crystal compound is contained in the liquid crystal composition forming the optically absorptive anisotropic film, the log P value of the component derived from the low molecular weight liquid crystal compound contained in the optically absorptive anisotropic film can be the log P value of the low molecular weight liquid crystal compound contained in the liquid crystal composition.

[0018] In the optically absorptive anisotropic film of the present invention, the angle θ between the transmittance central axis of the optically absorptive anisotropic film and the normal direction to the surface of the optically absorptive anisotropic film (hereinafter also abbreviated as "transmittance central axis angle θ") is preferably 0° or more and 45° or less, more preferably 0° or more and less than 45°, even more preferably 0° or more and 35° or less, and particularly preferably 0° or more and less than 35°, for the reason that the effects of the present invention, namely, a low haze value and a high degree of orientation, are manifested.

[0019] Here, the transmittance central axis of the optically absorptive anisotropic film refers to the direction that exhibits the highest transmittance when the transmittance is measured by changing the tilt angle (polar angle) and tilt direction (azimuth angle) relative to the normal direction of the optically absorptive anisotropic film surface (main surface). Specifically, the Mueller matrix at a wavelength of 550 nm is measured using an AxoScan (OPMF-2, manufactured by Axometrics). More specifically, during measurement, the azimuth angle at which the transmittance central axis is tilted is first found, and then, within a plane containing the normal direction of the optically absorptive anisotropic film along that azimuth angle (a plane containing the transmittance central axis and perpendicular to the film surface), the polar angle, which is the angle relative to the normal direction of the optically absorptive anisotropic film surface, is changed in 1° increments from -70 to 70°, and the Mueller matrix at a wavelength of 550 nm is measured, and the transmittance of the optically absorptive anisotropic film is derived. As a result, the direction with the highest transmittance is designated as the transmittance central axis. The transmittance central axis means the direction of the absorption axis (the direction of the long axis of the molecule) of the dichroic material contained in the optically absorptive anisotropic film.

[0020] The optically absorptive anisotropic film of the present invention is preferably a film obtained by fixing the alignment state of a liquid crystal composition containing a liquid crystal compound, a dichroic substance, etc. The components contained in the liquid crystal composition will be described in detail below. Note that, although each component described below is basically a component that is also contained in the optically absorptive anisotropic film, components having a crosslinkable group (including a polymerizable group) are contained in the optically absorptive anisotropic film as a crosslinked (polymerized) component for reasons such as fixing the alignment state.

[0021] <Liquid Crystal Compound> The liquid crystal composition contains a liquid crystal compound. This allows the dichroic material to be aligned with a higher degree of orientation while suppressing precipitation of the dichroic material. As the liquid crystal compound, either a polymer liquid crystal compound or a low molecular weight liquid crystal compound can be used, with a polymer liquid crystal compound being preferred because it allows for a higher degree of orientation. Furthermore, as the liquid crystal compound, a polymer liquid crystal compound and a low molecular weight liquid crystal compound may be used in combination. Here, the term "polymer liquid crystal compound" refers to a liquid crystal compound having a repeating unit in its chemical structure. The term "low molecular weight liquid crystal compound" refers to a liquid crystal compound having no repeating units in its chemical structure. Examples of polymer liquid crystal compounds include the thermotropic liquid crystal polymers described in JP 2011-237513 A and the polymer liquid crystal compounds described in paragraphs

[0012] to

[0042] of WO 2018 / 199096 A. Examples of low molecular weight liquid crystal compounds include those described in paragraphs

[0072] to

[0088] of JP 2013-228706 A, and among them, liquid crystal compounds exhibiting smectic properties are preferred. Examples of such liquid crystal compounds include those described in paragraphs

[0019] to

[0140] of WO 2022 / 014340 A, the disclosures of which are incorporated herein by reference. It should be noted that the liquid crystal compound is preferably a liquid crystal compound that does not exhibit dichroism in the visible light region.

[0022] The content of the liquid crystal 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, relative to 100 parts by mass of the content of the dichroic material described below. When the content of the liquid crystal compound is within the above range, the degree of orientation of the dichroic material is further improved. The liquid crystal compound may be contained alone, or two or more types may be contained. When two or more types of liquid crystal compounds are contained, the content of the liquid crystal compound refers to the total content of the liquid crystal compounds.

[0023] <Dichroic Material> The liquid crystal composition contains a dichroic material. Here, the dichroic material refers to a dye whose absorbance varies depending on the direction. The dichroic material may or may not exhibit liquid crystallinity.

[0024] The dichroic substance is not particularly limited, and examples thereof include visible light absorbing substances (dichroic dyes), luminescent substances (fluorescent substances, phosphorescent substances), ultraviolet absorbing substances, infrared absorbing substances, nonlinear optical substances, carbon nanotubes, and inorganic substances (e.g., quantum rods), and any conventionally known dichroic substance (dichroic dye) can be used. Specifically, for example, paragraphs

[0067] to

[0071] of JP 2013-228706 A, paragraphs

[0008] to

[0026] of JP 2013-227532 A, paragraphs

[0008] to

[0015] of JP 2013-209367 A, paragraphs

[0045] to

[0058] of JP 2013-14883 A, paragraphs

[0012] to

[0029] of JP 2013-109090 A, paragraphs

[0009] to

[0017] of JP 2013-101328 A, Paragraphs

[0051] to

[0065] of JP 2013-37353 A, paragraphs

[0049] to

[0073] of JP 2012-63387 A, paragraphs

[0016] to

[0018] of JP 11-305036 A, paragraphs

[0009] to

[0011] of JP 2001-133630 A, paragraphs

[0030] to

[0169] of JP 2011-215337 A, paragraphs

[0021] to

[0075] of JP 2010-106242 A, paragraphs

[0016] to

[0018] of JP 2010-215846 A

[0011] to

[0025] paragraphs,

[0017] to

[0069] paragraphs of JP 2011-048311 A,

[0013] to

[0133] paragraphs of JP 2011-213610 A,

[0074] to

[0246] paragraphs of JP 2011-237513 A,

[0005] to

[0051] paragraphs of JP 2016-006502 A,

[0014] to

[0032] paragraphs of JP 2018-053167 A, and

[0014] to

[0033] paragraphs of JP 2020-11716 A paragraphs

[0005] to

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

[0008] to

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

[0014] to

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

[0014] to

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

[0013] to

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

[0014] to

[0034] of International Publication No. 2018 / 164252,Examples include those described in paragraphs

[0021] to

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

[0043] to

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

[0043] to

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

[0050] to

[0074] of International Publication No. 2020 / 004106, and paragraphs

[0015] to

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

[0025] As the dichroic substance, a dichroic azo dye compound is preferred. A dichroic azo dye compound refers to an azo dye compound whose absorbance varies depending on the direction. A dichroic azo dye compound may or may not exhibit liquid crystallinity. When a dichroic azo dye compound exhibits liquid crystallinity, it may exhibit either nematic or smectic properties. The temperature range in which the liquid crystal phase is exhibited is preferably room temperature (approximately 20 to 28°C) to 300°C, and more preferably 50 to 200°C from the viewpoints of handleability and manufacturing suitability.

[0026] In the present invention, from the viewpoint of adjusting color hue, it is preferable to use, as the dichroic substance, a mixture containing at least a dye compound (particularly, a dichroic azo dye compound) having an absorption maximum in a wavelength range of 380 nm or more and less than 455 nm, a dye compound (particularly, a dichroic azo dye compound) having an absorption maximum in a wavelength range of 455 nm or more and less than 560 nm, and a dye compound (particularly, a dichroic azo dye compound) having an absorption maximum in a wavelength range of 560 nm or more and less than 700 nm.

[0027] In particular, in the present invention, it is preferable that the dye compound having a maximum absorption wavelength in the wavelength range of 380 nm or more and less than 455 nm contains a dichroic azo dye compound represented by the following formula (1).

[0028]

[0029] In the formula (1), A and B each independently represent a crosslinkable group. In the formula (1), a and b each independently represent 0 or 1, provided that a+b≧1. In the formula (1), when a=0, L １ represents a monovalent substituent, and when a=1, L １represents a single bond or a divalent linking group. ２ represents a monovalent substituent, and when b=1, L ２ represents a single bond or a divalent linking group. １ represents an (n1+2)-valent aromatic hydrocarbon group or heterocyclic group, Ar ２ represents an (n2+2)-valent aromatic hydrocarbon group or heterocyclic group, Ar ３ represents an (n3+2)-valent aromatic hydrocarbon group or heterocyclic group. １ , R ２ and R ３ each independently represents a monovalent substituent. When n1≧2, a plurality of R １ may be the same or different, and when n2≧2, a plurality of R ２ may be the same or different, and when n3≧2, a plurality of R ３ In the above formula (1), k represents an integer of 1 to 4. When k is 2 or more, a plurality of Ar ２ may be the same or different, and multiple R ２ may be the same or different. In the above formula (1), n1, n2, and n3 each independently represent an integer of 0 to 4. However, when k = 1, n1 + n2 + n3 ≧ 0, and when k ≧ 2, n1 + n2 + n3 ≧ 1. Explanations and examples of each symbol in the above formula (1) include those described in paragraphs

[0013] to

[0038] of WO 2017 / 195833, and these descriptions are incorporated herein by reference.

[0030] In the present invention, the dichroic azo dye compound represented by the above formula (1) is preferably a dichroic azo dye compound having a dichroic substance-derived endothermic peak at an endothermic onset temperature of 105° C. or higher, and ... １ ~Ar ３ Each of these represents a phenylene group, and R １ and R ３represents a halogen atom (especially chlorine) located at the ortho position of the azo bond (-N=N-), and when n2 is 1, R ２ represents an alkyl group (especially a methyl group), and L １ and L ２ Preferably, each of A and B represents an alkylene group having 2 to 6 carbon atoms, and A and B represent a (meth)acryloyloxy group.

[0031] The content of the dichroic substance contained in the optically absorptive anisotropic film is not particularly limited, but is preferably 3% by mass or more, more preferably 8% by mass or more, even more preferably 10% by mass or more, and particularly preferably 10 to 30% by mass, relative to the total mass of the optically absorptive anisotropic film, because the degree of orientation of the optically absorptive anisotropic film formed is high. When multiple dichroic substances are used in combination, the total amount of the multiple dichroic substances is preferably within the above-mentioned range. Furthermore, the content of the dichroic substance contained in the optically absorptive anisotropic film is preferably 20 to 650 mg / cm, because the degree of orientation of the optically absorptive anisotropic film formed is high. ３ is preferably 25 to 500 mg / cm ３ is preferably 30 to 200 mg / cm ３ More preferably, it is 40 to 150 mg / cm ３ When a plurality of dichroic substances are used in combination, the total amount of the dichroic substances is preferably in the above-mentioned range. ３ ) can be obtained by measuring a solution in which a laminate having an optically absorptive anisotropic film is dissolved, or an extract obtained by immersing the laminate in a solvent, by high-performance liquid chromatography (HPLC), but the above method is not limited to this. Quantification can be performed by using the dichroic substance contained in the optically absorptive anisotropic film as a standard sample. One example of a method for calculating the content of the dichroic substance is to calculate the volume by multiplying the thickness of the optically absorptive anisotropic film obtained from a microscopic image of the cross section of the laminate by the area of ​​the optical laminate used to measure the amount of dye, and then dividing the volume by the amount of dye measured by HPLC to calculate the dye content.

[0032] <Vertical Alignment Agent> The liquid crystal composition preferably contains a vertical alignment agent. Here, the vertical alignment agent refers to an additive having the function of aligning the liquid crystal compound in a direction perpendicular to the main plane of the optically absorptive anisotropic film. Note that "vertical alignment" does not require alignment at a strict 90° angle, but means alignment at an angle of 70 to 110°.

[0033] Examples of the vertical alignment agent include an ionic vertical alignment agent and a vertical alignment agent having a boronic acid group, and it is preferable to use an ionic vertical alignment agent and a vertical alignment agent having a boronic acid group in combination.

[0034] Suitable examples of the ionic vertical alignment agent include onium compounds represented by the following formula (B1).

[0035] In the formula (B1), ring A represents a quaternary ammonium ion consisting of a nitrogen-containing heterocycle, and X represents an anion. １ represents a divalent linking group. ２ represents a single bond or a divalent linking group. １ represents a divalent linking group having a 5-membered or 6-membered ring as a partial structure. Z represents a divalent linking group having an alkylene group having 2 to 20 carbon atoms as a partial structure. P １ and P ２ each independently represents a monovalent substituent having a polymerizable ethylenically unsaturated bond.

[0036] Ring A represents a quaternary ammonium ion consisting of a nitrogen-containing heterocycle. Examples of ring A include a pyridine ring, a picoline ring, a 2,2'-bipyridyl ring, a 4,4'-bipyridyl ring, a 1,10-phenanthroline ring, a quinoline ring, an oxazole ring, a thiazole ring, an imidazole ring, a pyrazine ring, a triazole ring, and a tetrazole ring, and are preferably a quaternary imidazolium ion or a quaternary pyridinium ion.

[0037] X represents an anion. Examples of X include halogen anions (e.g., fluorine ion, chloride ion, bromide ion, iodide ion, etc.), sulfonate ions (e.g., methanesulfonate ion, trifluoromethanesulfonate ion, methyl sulfate ion, vinyl sulfonate ion, allyl sulfonate ion, p-toluenesulfonate ion, p-chlorobenzenesulfonate ion, p-vinylbenzenesulfonate ion, 1,3-benzenedisulfonate ion, 1,5-naphthalenedisulfonate ion, 2,6-naphthalenedisulfonate ion, etc.), sulfate ion, carbonate ion, nitrate ion, thiocyanate ion, perchlorate ion, tetrafluoroborate ion, picrate ion, acetate ion, benzoate ion, p-vinylbenzoate ion, formate ion, trifluoroacetate ion, phosphate ion (e.g., hexafluorophosphate ion), hydroxide ion, etc. Preferred are halogen anions, sulfonate ions, and hydroxide ions. Particularly preferred are chloride ions, bromide ions, iodide ions, methanesulfonate ions, vinylsulfonate ions, p-toluenesulfonate ions, and p-vinylbenzenesulfonate ions.

[0038] L １ represents a divalent linking group. １ Examples of the group include an alkylene group, —O—, —S—, —CO—, and —SO ２ -, -NRa- (wherein Ra is an alkyl group having 1 to 5 carbon atoms or a hydrogen atom), an alkenylene group, an alkynylene group, or a divalent linking group having 1 to 20 carbon atoms formed in combination with an arylene group. １ is preferably -AL-, -O-AL-, -CO-O-AL-, or -O-CO-AL- having 1 to 10 carbon atoms, more preferably -AL- or -O-AL- having 1 to 10 carbon atoms, and most preferably -AL- or -O-AL- having 1 to 5 carbon atoms. AL represents an alkylene group.

[0039] L2 represents a single bond or a divalent linking group. ２ Examples of the group include an alkylene group, —O—, —S—, —CO—, and —SO ２-, -NRa- (wherein Ra is an alkyl group having 1 to 5 carbon atoms or a hydrogen atom), an alkenylene group, a divalent linking group having 1 to 10 carbon atoms formed in combination with an alkynylene group or an arylene group, a single bond, -O-, -O-CO-, -CO-O-, -O-AL-O-, -O-AL-O-CO-, -O-AL-CO-O-, -CO-O-AL-O-, -CO-O-AL-O-CO-, -CO-O-AL-CO-O-, -O-CO-AL-O-, -O-CO-AL-O-CO-, -O-CO-AL-CO-O-, and the like. AL represents an alkylene group. L2 is preferably a single bond, -AL-, -O-AL-, or -NRa-AL-O- having 1 to 10 carbon atoms, more preferably a single bond, -AL-, -O-AL-, or -NRa-AL-O- having 1 to 5 carbon atoms, and most preferably a single bond, or -O-AL- or -NRa-AL-O- having 1 to 5 carbon atoms.

[0040] Y １ represents a divalent linking group having a 5- or 6-membered ring as a partial structure. １ Examples of the aromatic ring include a cyclohexyl ring, an aromatic ring, a heterocyclic ring, etc. Examples of the aromatic ring include a benzene ring, an indene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, an anthracene ring, a biphenyl ring, and a pyrene ring, with a benzene ring, a biphenyl ring, and a naphthalene ring being particularly preferred. The heteroatom constituting the heterocycle is preferably a nitrogen atom, an oxygen atom, or a sulfur atom, and examples thereof include a furan ring, a thiophene ring, a pyrrole ring, a pyrroline ring, a pyrrolidine ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an imidazoline ring, an imidazolidine ring, a pyrazole ring, a pyrazoline ring, a pyrazolidine ring, a triazole ring, a furazan ring, a tetrazole ring, a pyran ring, a dioxane ring, a dithiane ring, a thiine ring, a pyridine ring, a piperidine ring, an oxazine ring, a morpholine ring, a thiazine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a piperazine ring, and a triazine ring. The heterocycle is preferably a 6-membered ring. Y １ The divalent linking group having a 5- or 6-membered ring as a partial structure, represented by the following formula (I), may further have a substituent (for example, the above-mentioned substituent W).

[0041] Y １ The divalent linking group represented by the formula (I) is preferably a divalent linking group having two or more 5- or 6-membered rings, and more preferably has a structure in which two or more rings are linked by a linking group. Examples of the linking group include L １ and L ２ Examples of the linking group include -C≡C-, -CH=CH-, -CH=N-, -N=CH-, and -N=N-.

[0042] Z represents a divalent linking group having an alkylene group having 2 to 20 carbon atoms as a partial structure and formed by combining -O-, -S-, -CO-, or -SO2-, and the alkylene group may have a substituent. Examples of the divalent linking group include an alkyleneoxy group and a polyalkyleneoxy group. The alkylene group represented by Z preferably has 2 to 16 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms.

[0043] P1 and P2 each independently represent a monovalent substituent having a polymerizable ethylenically unsaturated group. Examples of the monovalent substituent having a polymerizable ethylenically unsaturated group include the following formulae (M-1) to (M-8). That is, the monovalent substituent having a polymerizable ethylenically unsaturated group may be a substituent consisting only of an ethenyl group, as in (M-8).

[0044]

[0045] In formulas (M-3) and (M-4), R represents a hydrogen atom or an alkyl group, preferably a hydrogen atom or a methyl group. Among the formulas (M-1) to (M-8), (M-1), (M-2), and (M-8) are preferred, with (M-1) or (M-8) being more preferred. In particular, (M-1) is preferred as P1. Furthermore, (M-1) or (M-8) is preferred as P2. In compounds in which ring A is a quaternary imidazolium ion, P2 is preferably (M-8) or (M-1), and in compounds in which ring A is a quaternary pyridinium ion, P2 is preferably (M-1).

[0046] Examples of the onium compound represented by formula (B1) include the onium salts described in paragraphs

[0052] to

[0058] of JP-A No. 2012-208397, the onium salts described in paragraphs

[0024] to

[0055] of JP-A No. 2008-026730, and the onium salts described in JP-A No. 2002-37777.

[0047] As the ionic vertical alignment agent, in addition to the onium compound represented by the above formula (B1), for example, those described in paragraphs

[0017] to

[0029] of JP-A-2020-181150 can be mentioned.

[0048] A preferred example of the vertical alignment agent having a boronic acid group is a boronic acid compound represented by the following formula (B2).

[0049] In (B2) above, R １ and R ２ each independently represents a hydrogen atom, an aliphatic hydrocarbon group which may have a substituent, an aryl group which may have a substituent, or a heterocyclic group which may have a substituent. ３ represents a substituent.

[0050] R １ and R ２ Examples of the aliphatic hydrocarbon group represented by one embodiment of the formula include substituted or unsubstituted linear or branched alkyl groups having 1 to 20 carbon atoms (e.g., methyl, ethyl, isopropyl, etc.), substituted or unsubstituted cyclic alkyl groups having 3 to 20 carbon atoms (e.g., cyclohexyl, etc.), and alkenyl groups having 2 to 20 carbon atoms (e.g., vinyl, etc.). １ and R ２ Examples of the aryl group represented by one embodiment of R include a substituted or unsubstituted phenyl group having 6 to 20 carbon atoms (for example, a phenyl group, a tolyl group, etc.), and a substituted or unsubstituted naphthyl group having 10 to 20 carbon atoms. １ and R ２Examples of the heterocyclic group represented by one embodiment of R include substituted or unsubstituted 5- or 6-membered ring groups containing at least one heteroatom (e.g., nitrogen atom, oxygen atom, sulfur atom, etc.), and specific examples include a pyridyl group, an imidazolyl group, a furyl group, a piperidyl group, and a morpholino group. １ and R ２ may be linked together to form a ring, for example, R １ and R ２ The isopropyl groups may be linked to form a 4,4,5,5-tetramethyl-1,3,2-dioxaborolane ring.

[0051] R １ and R ２ is preferably a hydrogen atom, a linear or branched alkyl group having 1 to 3 carbon atoms, or a ring formed by linking these groups, and more preferably a hydrogen atom.

[0052] R ３ is preferably a substituent containing a functional group capable of bonding to a (meth)acrylic group. Here, examples of the functional group capable of bonding to a (meth)acrylic group include a vinyl group, an acrylate group, a methacrylate group, an acrylamide group, a styryl group, a vinyl ketone group, a butadiene group, a vinyl ether group, an oxiranyl group, an aziridinyl group, and an oxetane group. Among these, a vinyl group, an acrylate group, a methacrylate group, a styryl group, an oxiranyl group, or an oxetane group is preferred, and a vinyl group, an acrylate group, an acrylamide group, or a styryl group is more preferred.

[0053] R ３is preferably a substituted or unsubstituted aliphatic hydrocarbon group, an aryl group, or a heterocyclic group having a functional group capable of bonding to a (meth)acrylic group. Examples of the aliphatic hydrocarbon group include a substituted or unsubstituted linear or branched alkyl group having 1 to 30 carbon atoms (e.g., methyl group, ethyl group, isopropyl group, n-propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, hexadecyl group, octadecyl group, eicosyl group, isopropyl group, isobutyl group, sec-butyl group, tert Examples of the aryl group include substituted or unsubstituted phenyl groups having 6 to 50 carbon atoms (e.g., phenyl, tolyl, styryl, 4-benzoyloxyphenyl, 4-phenoxycarbonylphenyl, 4-biphenyl, 4-(4-octyloxybenzoyloxy)phenoxycarbonylphenyl), and substituted or unsubstituted naphthyl groups having 10 to 50 carbon atoms (e.g., unsubstituted naphthyl).Examples of heterocyclic groups include substituted or unsubstituted 5- or 6-membered ring groups containing at least one heteroatom (e.g., nitrogen atom, oxygen atom, sulfur atom, etc.), and examples thereof include pyrrole, furan, thiophene, pyrazole, imidazole, triazole, oxazole, isoxazole, oxadiazole, thiazole, thiadiazole, indole, carbazole, benzofuran, dibenzofuran, thianaphthene, dibenzothiophene, indazole, benzimidazole, anthranil, benzisoxazole, benzoxazole, benzothiazole, purine, pyridine, pyridazine, pyrimidine, pyrazine, triazine, quinoline, acridine, isoquinoline, phthalazine, quinazoline, quinoxaline, naphthyridine, phenanthroline, pteridine, morpholine, and piperidine groups.

[0054] Examples of the boronic acid compound represented by formula (B2) include the boronic acid compounds represented by general formula (I) described in paragraphs 0023 to 0032 of JP-A No. 2008-225281. Preferred examples of the compound represented by formula (B2) include the compounds exemplified below.

[0055]

[0056] When the liquid crystal composition contains a vertical alignment agent, the content of the vertical alignment agent is preferably 1.0 to 7.0 parts by mass, more preferably 1.5 to 8.0 parts by mass, and even more preferably 2.5 to 6.0 parts by mass, relative to 100 parts by mass of the liquid crystal compound. The vertical alignment agent may be contained alone or in combination of two or more types. When two or more types of liquid crystal compounds are contained, the content of the vertical alignment agent refers to the total content of the vertical alignment agents.

[0057] <Solvent> The liquid crystal composition preferably contains a solvent from the viewpoint of workability and the like. Examples of the solvent include ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, acetylacetone, etc.), ethers (e.g., dioxane, tetrahydrofuran, tetrahydropyran, dioxolane, tetrahydrofurfuryl alcohol, cyclopentyl methyl ether, dibutyl ether, etc.), aliphatic hydrocarbons (e.g., hexane, etc.), alicyclic hydrocarbons (e.g., cyclohexane, etc.), aromatic hydrocarbons (e.g., benzene, toluene, xylene, tetralin, trimethylbenzene, etc.), halogenated carbons (e.g., dichloromethane, trichloromethane (chloroform), dichloroethane, dichlorobenzene, 1,1,2,2-tetrachloroethane, chlorotoluene, etc.), esters (e.g., methyl acetate, ethyl acetate, butyl acetate, diethyl carbonate, ethyl acetoacetate, n-pentyl acetate, ethyl benzoate, benzyl benzoate, butyl carbitol acetate, diethylene glycol monoethyl ether acetate, Examples of suitable solvents include organic solvents such as ethanol, isopropanol, butanol, cyclohexanol, furfuryl alcohol, 2-ethylhexanol, octanol, benzyl alcohol, ethanolamine, ethylene glycol, propylene glycol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, phenols (e.g., phenol, cresol, 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, 1,3-dimethyl-2-imidazolidinone, etc.), and heterocyclic compounds (e.g., pyridine, 2,6-lutidine, etc.), as well as water. These solvents may be used alone or in combination of two or more.

[0058] When the liquid crystal composition contains a solvent, the content of the solvent is preferably 60 to 99.5% by mass, more preferably 70 to 99% by mass, and particularly preferably 75 to 98% by mass, relative to the total mass (100% by mass) of the liquid crystal composition.

[0059] <Polymerization initiator> The liquid crystal composition may contain a polymerization initiator. There are no particular limitations on the polymerization initiator, but it is preferably a photosensitive compound, i.e., a photopolymerization initiator. As the photopolymerization initiator, various compounds can be used without particular limitations. Examples of photopolymerization initiators include α-carbonyl compounds (U.S. Pat. Nos. 2,367,661 and 2,367,670), acyloin ethers (U.S. Pat. No. 2,448,828), α-hydrocarbon-substituted aromatic acyloin compounds (U.S. Pat. No. 2,722,512), polynuclear quinone compounds (U.S. Pat. Nos. 3,046,127 and 2,951,758), and combinations of triarylimidazole dimers and p-aminophenyl ketones (U.S. Pat. No. 3,549,367). ), acridine and phenazine compounds (JP 60-105667 A and U.S. Pat. No. 4,239,850 A), oxadiazole compounds (U.S. Pat. No. 4,212,970 A), o-acyloxime compounds (JP 2016-27384 A

[0065] ), and acylphosphine oxide compounds (JP 63-40799 A, JP 5-29234 A, JP 10-95788 A, and JP 10-29997 A). Commercially available photopolymerization initiators can also be used, including Irgacure-184, Irgacure-907, Irgacure-369, Irgacure-651, Irgacure-819, Irgacure-OXE-01, and Irgacure-OXE-02 manufactured by BASF.

[0060] When the liquid crystal composition contains a polymerization initiator, the content of the polymerization initiator is preferably 0.01 to 30% by mass, more preferably 0.1 to 15% by mass, based on the total solid mass of the liquid crystal composition.

[0061] <Surfactant> The liquid crystal composition may contain a surfactant. There are no particular limitations on the surfactant, and polymer surfactants and low molecular weight surfactants can be used, including compounds described in paragraphs

[0253] to

[0293] of JP-A No. 2011-237513. Furthermore, fluorine (meth)acrylate polymers and silicon polymers described in paragraphs

[0018] to

[0043] of JP-A No. 2007-272185 can also be used as surfactants. Examples of surfactants include compounds described in paragraphs

[0079] to

[0102] of JP-A-2007-069471, polymerizable liquid crystal compounds represented by formula (4) described in JP-A-2013-047204 (particularly compounds described in paragraphs

[0020] to

[0032] ), polymerizable liquid crystal compounds represented by formula (4) described in JP-A-2012-211306 (particularly compounds described in paragraphs

[0022] to

[0029] ), and liquid crystal alignment promoters represented by formula (4) described in JP-A-2002-129162 (particularly compounds described in paragraphs

[0032] to

[0032] ). Other examples that can be used include compounds described in paragraphs

[0076] to

[0078] and paragraphs

[0082] to

[0084] of the present invention, compounds represented by formulas (4), (II), and (III) described in JP-A-2005-099248 (particularly the compounds described in paragraphs

[0092] to

[0096] ), compounds described in paragraphs

[0013] to

[0059] of Japanese Patent No. 4,385,997, compounds described in paragraphs

[0018] to

[0044] of Japanese Patent No. 5,034,200, and compounds described in paragraphs

[0019] to

[0038] of Japanese Patent No. 4,895,088. One surfactant may be used alone, or two or more surfactants may be used in combination.

[0062] When the liquid crystal composition contains a surfactant, the content of the surfactant is preferably 0.005 to 15% by mass, more preferably 0.01 to 5% by mass, and even more preferably 0.015 to 3% by mass, based on the total mass of the solid content of the liquid crystal composition. When multiple surfactants are used in combination, the total amount of the multiple surfactants is preferably in the above-mentioned range.

[0063] [Method for Producing Optically Absorbent Anisotropic Film] The method for producing the optically absorptive anisotropic film of the present invention is not particularly limited, and examples thereof include a method comprising, in this order, a step of applying the above-described liquid crystal composition (hereinafter also referred to as "optically absorptive anisotropic film-forming composition") to form a coating film (hereinafter also referred to as "coating film formation step"), and a step of orienting the liquid crystalline component and dichroic substance contained in the coating film (hereinafter also referred to as "orientation step"). Note that the liquid crystalline component refers to a component that includes not only the above-described liquid crystal compound, but also the dichroic substance having liquid crystallinity, if the above-described dichroic substance has liquid crystallinity.

[0064] <Coating Film Forming Step> The coating film forming step is a step of forming a coating film by applying a composition for forming an optically absorptive anisotropic film. By using a composition for forming an optically absorptive anisotropic film containing the above-mentioned solvent, or by using a composition for forming an optically absorptive anisotropic film that has been converted into a liquid such as a molten liquid by heating, etc., it becomes easier to apply the composition for forming an optically absorptive anisotropic film. Specific examples of the coating method for the composition for forming an optically absorptive anisotropic film include known methods such as roll coating, gravure printing, spin coating, wire bar coating, extrusion coating, direct gravure coating, reverse gravure coating, die coating, spraying, and inkjet printing.

[0065] In the present invention, the coating amount of the dichroic material in the coating film forming step is set to 15 mg / m because the optical effect (for example, viewing angle control) is enhanced. ２ It is preferable that the concentration is 50 to 1000 mg / m or more. ２ More preferably, it is 200 to 800 mg / m ２ It is more preferable that:

[0066] <Orientation Step> The orientation step is a step of orienting the liquid crystalline component contained in the coating film. This results in an optically absorbing anisotropic film. The orientation step may include a drying treatment. Components such as the solvent can be removed from the coating film by the drying treatment. The drying treatment may be performed 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 component contained in the composition for forming an optically absorbing anisotropic film may be aligned by the above-mentioned coating film formation step or drying treatment. For example, in an embodiment in which the composition for forming an optically absorbing anisotropic film is prepared as a coating liquid containing a solvent, the coating film is dried to remove the solvent from the coating film, thereby obtaining a coating film with optically absorbing anisotropy (i.e., an optically absorbing anisotropic film). When the drying treatment is performed at a temperature equal to or higher than the transition temperature of the liquid crystalline component contained in the coating film to a liquid crystal phase, the heat treatment described below may not be performed.

[0067] The transition temperature of the liquid crystalline component contained in the coating film to the liquid crystal phase is preferably 10 to 250°C, more preferably 25 to 190°C, from the viewpoint of manufacturability and the like. When the transition temperature is 10°C or higher, no cooling treatment or the like is required to lower the temperature to the temperature range in which the liquid crystal phase is exhibited, and this is preferable. Furthermore, when the transition temperature is 250°C or lower, high temperatures are not required even when the film is once converted to an isotropic liquid state at a temperature higher than the temperature range in which the liquid crystal phase is exhibited, and this is preferable because waste of thermal energy and deformation and deterioration of the substrate can be reduced.

[0068] The orientation step preferably includes a heat treatment. This allows the liquid crystalline component contained in the coating film to be oriented, and the coating film after the heat treatment can be suitably used as an optically absorptive anisotropic film. From the viewpoint of manufacturability, the heat treatment is preferably performed at a temperature of 10 to 250°C, more preferably 25 to 190°C. The heating time is preferably 1 to 300 seconds, more preferably 1 to 60 seconds.

[0069] The alignment step may include a cooling treatment carried out after the heating treatment. The cooling treatment is a treatment in which the coated film after heating is cooled to about room temperature (20 to 25°C). This allows the alignment of the liquid crystalline component contained in the coated film to be fixed. The cooling method is not particularly limited and can be carried out by a known method. By the above steps, an optically absorptive anisotropic film can be obtained. In this embodiment, drying treatment and heating treatment are mentioned as methods for aligning the liquid crystalline component contained in the coated film, but the method is not limited thereto and can be carried out by a known alignment treatment.

[0070] <Other Steps> The method for forming an optically absorbing anisotropic film may include a step of curing the optically absorbing anisotropic film (hereinafter also referred to as a "curing step") after the alignment step. For example, when the optically absorbing anisotropic film has a crosslinkable group (polymerizable group), the curing step is performed by heating and / or light irradiation (exposure). Among these, the curing step is preferably performed by light irradiation. Various light sources, such as infrared, visible light, or ultraviolet light, can be used as the light source for curing, 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 depends on the transition temperature of the liquid crystal component contained in the liquid crystal film to the liquid crystal phase. Furthermore, exposure may be performed under a nitrogen atmosphere. When curing of the liquid crystal film proceeds by radical polymerization, exposure under a nitrogen atmosphere is preferred because inhibition of polymerization by oxygen is reduced.

[0071] The thickness of the optically absorptive anisotropic film of the present invention is not particularly limited, but is preferably 1.5 μm or more, more preferably 2 to 10 μm, and even more preferably 2 to 8 μm. Here, the thickness of the optically absorptive anisotropic film is measured by cutting the film with a microtome to prepare a cross-sectioned sample, and then observing the cross-section with a scanning electron microscope from the normal direction to the cross-section.

[0072] [Laminate] The laminate of the present invention includes the optically absorptive anisotropic film of the present invention described above. The laminate of the present invention may also include at least one of a polarizer layer, an antireflection layer, and a retardation layer.

[0073] [Polarizer Layer] The polarizer layer is not particularly limited as long as it is a member capable of converting light into specific linearly polarized light, and conventionally known absorptive polarizers and reflective polarizers can be used. Examples of absorptive polarizers include iodine-based polarizers, dye-based polarizers using dichroic dyes, and polyene-based polarizers. Iodine-based polarizers and dye-based polarizers include coated polarizers and stretched polarizers, and either can be used. However, coated polarizers are preferred. In addition, methods for obtaining a polarizer by stretching and dyeing a laminated film having a polyvinyl alcohol layer formed on a substrate are described in Japanese Patent Nos. 5048120, 5143918, 4691205, 4751481, and 4751486. ​​These known techniques related to polarizers can also be preferably used. Examples of coated polarizers include those disclosed in WO2018 / 124198, WO2018 / 186503, WO2019 / 132020, WO2019 / 132018, WO2019 / 189345, JP2019-197168A, JP2019-194685A, and JP2019-139222A, and known techniques relating to these polarizers can also be preferably utilized. Examples of reflective polarizers that can be used include polarizers in which thin films with different birefringences are laminated, wire grid polarizers, and polarizers in which a cholesteric liquid crystal having a selective reflection region is combined with a quarter-wave plate. Among these, polyvinyl alcohol-based resins (-CH ２A polymer containing -CHOH- as a repeating unit. In particular, a polarizer containing at least one selected from the group consisting of polyvinyl alcohol and an ethylene-vinyl alcohol copolymer is preferred. Furthermore, from the viewpoint of imparting crack resistance, the polarizer may have depolarizing portions formed along opposing edges. Examples of depolarizing portions include those described in JP 2014-240970 A. The polarizer may also have non-polarizing portions arranged at predetermined intervals in the longitudinal direction and / or width direction. The non-polarizing portions are partially bleached portions. The arrangement pattern of the non-polarizing portions can be appropriately set depending on the purpose. For example, when the polarizer is cut (cut, punched, etc.) to a predetermined size for installation in an image display device of a predetermined size, the non-polarizing portions are arranged in positions corresponding to the camera portion of the image display device. Examples of arrangement patterns of non-polarizing portions include those described in JP 2016-27392 A.

[0074] [Antireflection Layer] The antireflection layer is not particularly limited, and a known antireflection layer can be used. Examples of the antireflection layer include the antireflection layers described in paragraphs 0108 to 0121 of WO 2016 / 047648, the contents of which are incorporated herein by reference.

[0075] [Retardation layer] There is no particular limitation on retardation layer, and known retardation layer can be used.For example, retardation layer can be stretched polycarbonate film, stretched norbornene polymer film, transparent film containing and oriented inorganic particles having birefringence such as strontium carbonate, thin film obtained by obliquely depositing inorganic dielectric on support, film that uniaxially oriented and fixed orientation of liquid crystal compound, etc.In addition, as retardation layer, film that uniaxially oriented and fixed orientation of the above-mentioned liquid crystal compound is preferred.

[0076] [Image display device] The image display device of the present invention is an image display device having the laminate of the present invention. The display element used in the image display device of the present invention is not particularly limited, and examples thereof include a liquid crystal cell, an organic electroluminescence (hereinafter abbreviated as "EL") display panel, an inorganic EL display panel, and a plasma display panel.

[0077] [Viewing Angle Switching Device] The image display device of the present invention may be an image display device having the laminate of the present invention and an electronically controlled viewing angle switching cell, i.e., an image display device (viewing angle switching device) capable of switching the viewing angle. By using the optically absorbing anisotropic film of the present invention, it is possible to narrow the light emission angle. Various types of image display devices capable of switching the viewing angle are known, and the optically absorbing anisotropic film or laminate of the present invention can be used to generate light with a narrow emission angle. For example, after generating light with a narrow emission angle using the optically absorbing anisotropic film or laminate of the present invention, the light can be passed through an element that controls the diffusion of light, as described in JP-A-9-105907, thereby switching between a narrow viewing angle and a wide viewing angle. Alternatively, as described in JP 2017-098246 A, in a narrow viewing angle / wide viewing angle switchable backlight system consisting of, from the viewing side, an inverted prism sheet, a first light guide plate that directs light into the inverted prism sheet at a relatively large incident angle (light exiting from the inverted prism sheet has a narrow viewing angle), an optical filter element that absorbs obliquely incident light and directs light with a narrow exit angle into the inverted prism sheet at a relatively small incident angle, and a second light guide plate (light exiting from the inverted prism sheet has a narrow viewing angle), the optically absorptive anisotropic film or laminate of the present invention can be used as the optical filter element. The optically absorbing anisotropic film or laminate of the present invention can also be used as the optical filter in a backlight system in which, from the viewing side, a first light guide plate, an optical filter that absorbs obliquely incident light and emits it at a narrow angle, and a second light guide plate are stacked in this order, and in which, of the first and second light guide plates, a wide viewing angle is achieved when light is emitted from the first light guide plate, and a narrow viewing angle is achieved when light is emitted only from the second light guide plate. Furthermore, a retardation modulation element such as a liquid crystal cell can be disposed between the optically absorbing anisotropic film of the present invention and a horizontally aligned polarizer to switch between a narrow viewing angle and a wide viewing angle. For example, when a VA-mode or ECB-mode liquid crystal cell is used as the retardation modulation cell, a narrow viewing angle is achieved when the liquid crystal in the liquid crystal cell is vertically aligned, and a wide viewing angle mode is achieved when the liquid crystal in the liquid crystal cell is tilted, and the narrow viewing angle / wide viewing angle can be controlled by applying or not applying a voltage to the cell. An IPS-mode liquid crystal cell can also be used as the retardation modulation cell.The alignment direction of the liquid crystal cell when no voltage is applied and the absorption axis direction of the horizontally aligned polarizer are set parallel or perpendicular to each other, and by applying a voltage to change the alignment direction of the liquid crystal cell, the viewing angle can be switched from a narrow viewing angle to a wide viewing angle. Furthermore, a TN-mode liquid crystal cell can also be used as the retardation modulation cell. A cell in which the twist angle of the alignment can be switched between 0° and 90° or between 0° and 270° by turning the voltage on and off is preferred. Additionally, the image display device of the present invention may be configured to be capable of independently switching the viewing angles of multiple regions within the display screen.

[0078] [Optical Device / Head Mounted Display] The optically absorptive anisotropic film of the present invention can be used in an optical device (head mounted display) having a light guide plate on the surface of which a diffractive element is arranged.

[0079] Fig. 1 is a schematic diagram of an example of a head-mounted display of the present invention. The head-mounted display 80 shown in Fig. 1 is, as an example, AR glasses, and includes a light guide plate 82, an incident diffraction element 90 and an exit diffraction element 92 arranged on one surface of the light guide plate 82, an optical filter 10, and an image display element 86. The light guide plate 82, the incident diffraction element 90 and the exit diffraction element 92, and the optical filter 10 constitute a laminate of the present invention.

[0080] 1, an incident diffraction element 90 is disposed on the surface (principal surface) on one end side of the light guide plate 82. An output diffraction element 92 is disposed on the surface on the other end side of the light guide plate 82. The position of the incident diffraction element 90 is determined by the angle at which the image light I from the image display element 86 to the light guide plate 82 is incident. １ On the other hand, the position of the output diffraction element 92 corresponds to the incident position of the image light I from the light guide plate 82. １ The exit position of the image light I １1 corresponds to the observation position of the light guide plate 82. The incident diffraction element 90 and the exit diffraction element 92 are disposed on the same surface of the light guide plate 82. The optical filter 10 is disposed on the surface of the light guide plate 82 opposite to the surface on which the exit diffraction element 92 is disposed, facing the exit diffraction element 92. As shown in FIG. 1, the optical filter 10 has a shape similar to that of the exit diffraction element 92. An intermediate diffraction element 94 may be provided on the light guide plate 82 (see FIG. 2). The positions of the diffraction elements are not limited to the ends of the light guide plate, and various positions can be used depending on the shape of the light guide plate, etc.

[0081] In the head-mounted display 80 (AR glasses) configured as described above, the image light I displayed by the image display element 86 is １ As shown by the arrow, the image light I is diffracted by the incident diffraction element 90 and enters the light guide plate 82 at an angle at which it is totally reflected at the interface between the light guide plate 82 and the air. １ is totally reflected by both surfaces of the light guide plate 82, is guided through the light guide plate 82, and is incident on the output diffraction element 92. １ is diffracted by the output diffraction element 92 in a direction perpendicular to the surface of the output diffraction element 92. １ is emitted to a viewing position outside the light guide plate 82 for viewing by the user. It is preferable to have an air gap between the optical filter 10 and the light guide plate 82. If there is no air gap, the image light I １ is incident on the optical filter 10, and the image light I １ However, when the image light I propagates through the optical filter 10, is totally reflected by the surface of the optical filter 10 opposite to the light guide plate 82, and then propagates again through the optical filter 10, it is attenuated by absorption. By providing an air gap between the optical filter 10 and the light guide plate 82, the image light I propagates from the light guide plate to the optical filter. １ is not incident, and the above problem can be solved.

[0082] As shown in FIG. 1, external light I entering the head-mounted display 80 from the front direction ０That is, the background light passes through the optical filter 10, enters the light guide plate 82, passes through the output diffraction element 92, and reaches the observation position of the user. In the following description, external light that enters the head-mounted display 80 from the front direction is referred to as front external light I. ０ As a result, the head mounted display 80 causes the image displayed by the image display element 86 to enter one end of the light guide plate 82, propagate therethrough, and exit from the other end, thereby superimposing a virtual image on the view that the user is actually seeing.

[0083] The shape of the optical filter 10 is not limited to the same as the shape of the diffraction element, and may be different in shape and size. ｓ and the background, i.e., the front external light I ０ In order to prevent unnecessary light blocking, it is preferable that the diffraction element and the optical filter have the same shape, including the same size.

[0084] There are no particular limitations on the light guide plate 82, and any conventional light guide plate used in image display devices, etc., such as light guide plates used in various types of AR glasses and light guide plates used in backlight units of liquid crystal display devices, can be used.

[0085] There are no limitations on the image display element 86, and various known image display elements (displays) used in various image display devices such as AR glasses can be used. Examples of the image display element 86 include a liquid crystal display (including LCOS (Liquid Crystal On Silicon)), an organic electroluminescence display, an inorganic electroluminescence display, a DLP (Digital Light Processing), a MEMS (Micro-Electro-Mechanical Systems) display, and a micro LED (Light-Emitting Diode) display. Note that the image display element 86 may be one that displays monochrome images, two-color images, or color images.

[0086] The optical device of the present invention has an optical filter including the laminate of the present invention covering the diffraction element, preferably an optical filter including the laminate 14 and a polarizer 12 as in the illustrated example. By having such an optical filter 10 (10m), the optical device of the present invention can reduce the amount of light emitted from the front direction (front external light I) when used in a head-mounted display such as AR glasses. ０ ) has a high light transmittance, i.e., the visibility of the background is excellent, and external light (oblique external light I) incident from above the observer's head (diagonally above and in front of the observer's head) is also excellent. ｓ Furthermore, the optical device of the present invention can preferably suppress rainbow unevenness caused by external light incident not only from above and in front of the viewer's head, but also from diagonally ahead above the viewer's head (diagonally above and in front).

[0087] In the optical device of the present invention, the angle between the absorption axis (the alignment direction of the liquid crystal compound) of the laminate 14 constituting the optical filter 10 and the normal direction of the laminate 14 is 0 to 45°. That is, the laminate 14 has an absorption axis extending in the normal direction to the principal surface of the laminate 14 and the principal surface of the light guide plate 82. On the other hand, the polarizer 12 constituting the optical filter 10 is a polarizer having an absorption axis in the principal surface. That is, the polarizer has an absorption axis parallel to the principal surface of the laminate 14 and the principal surface of the light guide plate 82. Note that in the present invention, when the optical filter includes the laminate 14 and the polarizer 12, it is preferable to place the laminate 14 on the light guide plate 82 side from the viewpoint of improving light resistance.

[0088] The present invention will be described in more detail below with reference to examples. The materials, amounts used, ratios, treatment details, and treatment procedures shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the examples shown below.

[0089] Example 1 (1) Temporary Support A cellulose acylate film 1 (TAC substrate having a thickness of 60 μm; Fujitac TG60UL, Fujifilm Corporation) was used as a temporary support after the surface thereof was saponified with an alkaline solution.

[0090] (2) Preparation of Alignment Film A composition 1 for forming an alignment film having the following composition was applied onto a cellulose acylate film 1. The support on which the coating film was formed was dried with hot air at 145°C for 120 seconds to form an alignment film 1. The thickness of the alignment film 1 was 0.5 µm.

[0091] ------------------------------------------------------------------ Composition 1 for forming alignment film -------------------------------------------------- Polymer PA-1 (described below) 10.0 parts by mass Acid generator PAG-1 (described below) 0.83 parts by mass Stabilizer DIPEA (described below) 0.06 parts by mass Butyl acetate 100 parts by mass Methyl ethyl ketone 25 parts by weight ------------------------------------------------------------------

[0092] Polymer PA-1

[0093] Acid generator PAG-1

[0094] Stabilizer DIPEA

[0095] (3) Preparation of Optically Absorbent Anisotropic Film An optically absorptive anisotropic film-forming composition 1 having the following composition was applied to the obtained TAC (triacetyl cellulose) film with an alignment film using a wire bar, heated at 120°C for 60 seconds, and then cooled to 35°C. The film was then heated at 75°C for 60 seconds and cooled again to room temperature. Thereafter, under nitrogen purging conditions (oxygen concentration 100 ppm or less), an LED (light emitting diode) lamp (center wavelength 365 nm) was used to illuminate the film from the normal direction at an illuminance of 200 mW / cm. ２ The light was irradiated for 2 seconds under the irradiation condition of 1.0 to 1.5, thereby forming an optically absorptive anisotropic film 1 on the alignment film 1. The film thickness of the optically absorptive anisotropic film 1 was 4.5 μm.

[0096] 0.16 parts by mass of vertical alignment agent E-1 below 0.16 parts by mass of vertical alignment agent E-2 below 0.007 parts by mass of surfactant F-1 below 0.007 parts by mass of surfactant F-2 below 0.007 parts by mass of surfactant F-3 ... ----------------------------------------------------------------------------------

[0097] Dichroic substance D-1 (maximum absorption wavelength: 410 nm)

[0098] Dichroic substance D-2 (maximum absorption wavelength: 455 nm)

[0099] Dichroic substance D-3 (maximum absorption wavelength: 612 nm)

[0100] Polymer liquid crystal compound P-1 (weight average molecular weight: 20000)

[0101] Low molecular weight liquid crystal compound L-1 (a mixture of the following liquid crystal compounds (RA), (RB), and (RC) in a mass ratio of 84:14:2)

[0102] Vertical alignment agent E-1

[0103] Vertical alignment agent E-2

[0104] Surfactant F-1 (in the formula below, the numbers indicate the content (% by mass) of each repeating unit relative to the total repeating units. TMS represents a trimethylsilyl group.) (weight average molecular weight: 28,500)

[0105] (4) Preparation of Protective Layer The surface of the obtained optically absorptive anisotropic film 1 was subjected to a corona treatment under conditions of 4.0 m / min, 440 W, and a clearance of 2.0 mm. Next, a protective layer-forming coating solution 1 having the following composition was applied to the corona-treated optically absorptive anisotropic film 1 using a wire bar to form a coating film. Next, the temporary support on which the coating film had been formed was dried with hot air at 60°C for 60 seconds and then with hot air at 100°C for 120 seconds to form protective layer 1. Thereafter, under nitrogen purging conditions (oxygen concentration 100 ppm or less), an LED lamp (center wavelength 365 nm) was used to illuminate the film normal direction at an illuminance of 200 mW / cm. ２ The protective layer 1 was formed on the optically absorbing anisotropic film 1 by irradiating the film for 2 seconds under the irradiation conditions of

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[0106] -------------------------------------------------- Protective layer coating liquid formulation 1 -------------------------------------------------- 3.80 parts by mass of modified polyvinyl alcohol PVA-1 shown below 0.20 parts by mass IRGACURE 2959 (manufactured by BASF) 0.08 parts by mass of dye compound G-1 shown below Water 70 parts by mass Methanol 30 parts by mass --------------------------------------------------

[0107] Modified polyvinyl alcohol PVA-1 (in the formula below, the numbers indicate the content (% by mass) of each repeating unit relative to the total repeating units.) (Degree of polymerization: 1700)

[0108] Dye compound G-1

[0109] [Example 2] An optically absorbing anisotropic film 2 (layer structure: temporary support 1 / alignment film 1 / optically absorbing anisotropic film 2 / protective layer 1) was prepared in the same manner as in Example 1, except that an optically absorbing anisotropic film 2 prepared by replacing the optically absorbing anisotropic film-forming composition 1 with an optically absorbing anisotropic film-forming composition 2 having the following composition was used.

[0110] 0.16 parts by mass of the above-mentioned alignment agent E-1; 0.16 parts by mass of the above-mentioned alignment agent E-2; 0.007 parts by mass of the above-mentioned surfactant F-1; 0.91 parts by mass of the above-mentioned dichroic material D-1; 0.22 parts by mass of the above-mentioned dichroic material D-2; 1.49 parts by mass of the above-mentioned dichroic material D-3; 8.15 parts by mass of the following polymer liquid crystal compound P-2; 1.85 parts by mass of the above-mentioned low molecular weight liquid crystal compound L-1; 0.20 parts by mass of IRGACUE OXE-2 (manufactured by BASF); 0.16 parts by mass of the above-mentioned alignment agent E-1; 0.16 parts by mass of the above-mentioned alignment agent E-2; 0.007 parts by mass of the above-mentioned surfactant F-1; 78.17 parts by mass of cyclopentanone; 8.69 parts by mass of benzyl alcohol ----------------------------------------------------------------------------------

[0111] Polymer liquid crystal compound P-2 (weight average molecular weight: 21000)

[0112] [Example 3] An optically absorbing anisotropic film 3 (layer structure: temporary support 1 / alignment film 1 / optically absorbing anisotropic film 3 / protective layer 1) was prepared in the same manner as in Example 1, except that an optically absorbing anisotropic film 3 prepared by replacing the optically absorbing anisotropic film-forming composition 1 with the optically absorbing anisotropic film-forming composition 3 having the following composition was used.

[0113] 0.16 parts by mass of the above-mentioned alignment agent E-1; 0.16 parts by mass of the above-mentioned alignment agent E-2; 0.007 parts by mass of the above-mentioned surfactant F-1; 0.91 parts by mass of the above-mentioned dichroic material D-1; 0.22 parts by mass of the above-mentioned dichroic material D-2; 1.49 parts by mass of the above-mentioned dichroic material D-3; 8.15 parts by mass of the following polymer liquid crystal compound P-3; 1.85 parts by mass of the above-mentioned low molecular weight liquid crystal compound L-1; 0.20 parts by mass of IRGACUE OXE-2 (manufactured by BASF); 0.16 parts by mass of the above-mentioned alignment agent E-1; 0.16 parts by mass of the above-mentioned alignment agent E-2; 0.007 parts by mass of the above-mentioned surfactant F-1; 78.17 parts by mass of cyclopentanone; 8.69 parts by mass of benzyl alcohol ----------------------------------------------------------------------------------

[0114] Polymer liquid crystal compound P-3 (weight average molecular weight: 19000)

[0115] [Comparative Example 1] An optically absorbing anisotropic film H1 (layer structure: temporary support 1 / alignment film 1 / optically absorbing anisotropic film H1 / protective layer 1) was prepared in the same manner as in Example 1, except that an optically absorbing anisotropic film H1 prepared by replacing the optically absorbing anisotropic film-forming composition 1 with an optically absorbing anisotropic film-forming composition H1 having the following composition was used.

[0116] 0.16 parts by mass of the alignment agent E-1 0.16 parts by mass of the alignment agent E-2 0.16 parts by mass of the alignment agent E-2 0.007 parts by mass of the surfactant F-1 0.007 parts by mass of the surfactant F-2 0.007 parts by mass of the surfactant F-2 0.007 parts by mass of the surfactant F-3 0.007 parts by mass of the surfactant F-2 0.007 parts by mass of the surfactant F-3 0.007 parts by mass of the surfactant F-3 0.007 parts by mass of the surfactant F-4 0.007 parts by mass of the surfactant F-2 0.007 parts by mass of the surfactant F-3 ... ----------------------------------------------------------------------------------

[0117] Dichroic substance D-4 (maximum absorption wavelength: 418 nm)

[0118] [Comparative Example 2] An optically absorbing anisotropic film H2 (layer structure: temporary support 1 / alignment film 1 / optically absorbing anisotropic film H2 / protective layer 1) was prepared in the same manner as in Example 1, except that an optically absorbing anisotropic film H2 prepared by replacing the optically absorbing anisotropic film-forming composition 1 with an optically absorbing anisotropic film-forming composition H2 having the following composition was used.

[0119] 0.13 parts by mass of the above-mentioned dichroic material D-2 0.17 parts by mass of the above-mentioned dichroic material D-3 1.13 parts by mass of the above-mentioned polymer liquid crystal compound P-1 8.18 parts by mass of the above-mentioned polymer liquid crystal compound P-1 0.16 parts by mass of IRGACUE OXE-2 (manufactured by BASF) 0.13 parts by mass of the above-mentioned alignment agent E-1 0.13 parts by mass of the above-mentioned alignment agent E-2 0.004 parts by mass of the below-mentioned surfactant F-2 85.01 parts by mass of cyclopentanone 4.47 parts by mass of benzyl alcohol

[0120] Dichroic substance D-5 (maximum absorption wavelength: 415 nm)

[0121] Surfactant F-2 (in the formula below, the numbers indicate the content (% by mass) of each repeating unit relative to the total repeating units.) (Weight molecular weight: 16,000)

[0122] [Comparative Example 3] An optically absorbing anisotropic film H3 (layer structure: temporary support 1 / alignment film 1 / optically absorbing anisotropic film H3 / protective layer 1) was prepared in the same manner as in Example 1, except that an optically absorbing anisotropic film H3 prepared by replacing the optically absorbing anisotropic film-forming composition 1 with an optically absorbing anisotropic film-forming composition H3 having the following composition was used.

[0123] 0.16 parts by mass of the above alignment agent E-1; 0.16 parts by mass of the above alignment agent E-2; 0.007 parts by mass of the above surfactant F-1; 0.007 parts by mass of the above alignment agent E-2; 0.007 parts by mass of the above alignment agent E-3; 0.91 parts by mass of the above dichroic material D-5; 0.22 parts by mass of the above dichroic material D-2; 1.49 parts by mass of the above dichroic material D-3; 8.15 parts by mass of the above polymer liquid crystal compound P-1; 1.85 parts by mass of the above low molecular weight liquid crystal compound L-1; 0.20 parts by mass of IRGACUE OXE-2 (manufactured by BASF Corporation); 0.16 parts by mass of the above alignment agent E-1; 0.16 parts by mass of the above alignment agent E-2; 0.007 parts by mass of the above surfactant F-1; 78.17 parts by mass of cyclopentanone; 8.69 parts by mass of benzyl alcohol ----------------------------------------------------------------------------------

[0124] The transmittance central axis angle θ of the optically absorptive anisotropic films prepared in Examples 1 to 3 and Comparative Examples 1 to 3 was measured by the method described above, and was found to be 0° in all cases.

[0125] [Evaluation] (1) Physical Properties A light-absorbing anisotropic film was scraped off from the obtained light-absorbing anisotropic film, and DSC was performed using the method described above to measure the endothermic onset temperature of the endothermic peak derived from the dichroic substance and the maximum endothermic peak temperature of the matrix. The results are shown in Table 1 below. As described above, FIG. 4 shows the DSC curve of the light-absorbing anisotropic film prepared in Example 1, FIG. 5 shows the DSC curve of the light-absorbing anisotropic film prepared in Comparative Example 1, and FIG. 6 shows the DSC curve of only the matrix contained in the light-absorbing anisotropic films prepared in Example 1 and Comparative Example 1. The ΔlogP values ​​of the dichroic substance and the matrix were also calculated using the method described above. The results are shown in Table 1 below.

[0126] (2) Degree of Orientation The degree of orientation of the obtained optically absorptive anisotropic film at wavelengths of 450 nm and 550 nm was calculated by the following method. Using an AxoScan OPMF-1 (manufactured by Optoscience), during measurement, the polar angle, which is the angle relative to the normal direction of the optically absorptive anisotropic layer, was changed in 1° increments from -70 ° to 70 °, and the Mueller matrix at wavelengths of 450 nm and 550 nm at each polar angle was measured to derive the minimum transmittance (Tmin). Next, after removing the influence of surface reflection, Tmin at the polar angle at which Tmin is highest is defined as Tm(0), and Tmin in the direction 40 ° polar angle larger than the polar angle at which Tmin is highest is defined as Tm(40). The absorbance (A) was calculated from the obtained Tm(0) and Tm(40) using the following formula, and A(0) and A(40) were calculated. A = -log(Tm), where Tm represents transmittance and A represents absorbance. From the calculated A(0) and A(40), the degree of orientation at a wavelength of 450 nm (S(450)) and the degree of orientation at a wavelength of 550 nm (S(550)), defined by the following formula, were calculated. The results are shown in Table 1 below. Note that if S(450 nm) is 0.90 or higher, the degree of orientation can be evaluated as high. S = (4.6 x A(40) - A(0)) / (4.6 x A(40) + 2 x A(0))

[0127] (3) Haze Value The haze values ​​of the optically absorptive anisotropic films prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were measured using a haze meter (NDH2000, manufactured by Nippon Denshoku Industries Co., Ltd.) in an environment of 25°C and relative humidity of 55%. The results are shown in Table 1 below. The haze value was measured using each prepared optically absorptive anisotropic film, n = 3 measurements, and the average value was taken as the haze value. The measurement was performed so that light was incident from the temporary support side. A haze value of 0.50% or less can be evaluated as low.

[0128]

[0129] The results shown in Table 1 indicate that when the endothermic onset temperature of the endothermic peak derived from the dichroic substance observed by DSC is less than 105°C, the degree of orientation is low and the haze value is high (Comparative Examples 1 to 3). In contrast, when the endothermic onset temperature of the endothermic peak derived from the dichroic substance observed by DSC is 105°C or higher, the degree of orientation is high and the haze value is low (Examples 1 to 3). In particular, a comparison of Examples 1 to 3 indicates that when the maximum endothermic peak temperature of the matrix is ​​108°C or higher, the haze value is further reduced.

[0130] REFERENCE SIGNS LIST 10 Optical filter 12 Polarizer 14 Laminate 80 Head-mounted display 82 Light guide plate 90 Incident diffraction element 92 Outgoing diffraction element 94 Intermediate diffraction element I ０ Front external light I １ Video Light I ｓ Oblique external light

Claims

1. An optically absorptive anisotropic film containing a dichroic substance and a matrix consisting of all components other than the dichroic substance, in which at least one endothermic peak derived from the dichroic substance is observed by differential scanning calorimetry, and all of the endothermic peaks have endothermic onset temperatures of 105° C. or higher. Here, the endothermic onset temperature refers to a temperature that shows a heat flow of 6% when the heat flow at the endothermic peak top is taken as 100% in a differential scanning calorimetry curve with the heat flow on the vertical axis and the temperature on the horizontal axis, and is lower than the temperature at the endothermic peak top.

2. The optically absorbing anisotropic film according to claim 1, in which at least one endothermic peak originating from the matrix is ​​observed by differential scanning calorimetry, and the peak top of the endothermic peak showing the maximum heat flow among the endothermic peaks is observed in a temperature range of 108°C or higher.

3. The optically absorptive anisotropic film according to claim 1 or 2, wherein the absolute value of the difference between the log P value of the dichroic substance and the log P value of the matrix is ​​4.8 to 5.

8.

4. The optically absorptive anisotropic film according to claim 1 or 2, wherein the angle θ between the central axis of transmittance of the optically absorptive anisotropic film and the normal direction to the surface of the optically absorptive anisotropic film is from 0° to 45°.

5. The optically absorptive anisotropic film according to claim 1 or 2, wherein the dichroic substance is a mixture containing at least a dye compound having a maximum absorption wavelength in the wavelength range of 380 nm or more and less than 455 nm, a dye compound having a maximum absorption wavelength in the wavelength range of 455 nm or more and less than 560 nm, and a dye compound having a maximum absorption wavelength in the wavelength range of 560 nm or more and 700 nm or less.

6. A laminate comprising the optically absorptive anisotropic film according to claim 1 or 2.

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