Light-absorbing anisotropic film and laminate

Abstract

The present invention addresses the problem of providing: a light-absorbing anisotropic film having a low haze value and a high degree of orientation; and a laminate having the light-absorbing anisotropic film. This light-absorbing anisotropic film contains a dichroic substance and a matrix comprising all components other than the dichroic substance, and is characterized in that at least one endothermic peak derived from the dichroic substance is observed by differential scanning calorimetry, and all endothermic peaks have an endothermic initiation temperature of 105 DEG C or higher.

Description

Technical Field

[0001] This invention relates to a light-absorbing anisotropic film and a laminate. Background Technology

[0002] To prevent peeping or viewing angle control of image display devices, techniques are known and used in light-absorbing anisotropic films having an absorption axis in the thickness direction.

[0003] 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 of 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 less than 20%."

[0004] Existing technical documents Patent documents Patent Document 1: International Publication No. 2022 / 270466 Summary of the Invention

[0005] The technical problem to be solved by the invention The inventors have studied the light-absorbing anisotropic layer (light-absorbing anisotropic film) of the optical film described in Patent Document 1 and found that it has a high haze value and also has room for improvement in orientation.

[0006] Therefore, the objective of this invention is to provide a light-absorbing anisotropic film with low haze and high orientation, and a laminate having the light-absorbing anisotropic film.

[0007] means for solving technical problems The inventors conducted in-depth research to achieve the above-mentioned objectives and discovered that at least one endothermic peak originating from a dichroic substance was observed using differential scanning calorimetry (DSC). Furthermore, the endothermic onset temperature of all observed endothermic peaks reached 105°C or higher, resulting in a light-absorbing anisotropic film with low haze and high orientation. This led to the completion of the present invention.

[0008] That is, the inventors have discovered that the above-mentioned problems can be solved by the following structure.

[0009] [1] A light-absorbing anisotropic film, comprising a dichroic substance and a matrix composed of all components other than the dichroic substance, wherein the light-absorbing anisotropic film, At least one endothermic peak originating from a dichroic substance was observed by differential scanning calorimetry. All endothermic peaks had an endothermic onset temperature of 105 °C or higher.

[0010] Here, the endothermic onset temperature refers to the temperature at which 6% of the heat flow is displayed when the heat flow at the peak of the endothermic peak is set to 100% in a differential scanning calorimetry curve with the vertical axis set to heat flow and the horizontal axis set to temperature, and it is a temperature lower than the temperature at the peak of the endothermic peak.

[0011] [2] According to the light-absorbing anisotropic film described in [1], wherein, At least one endothermic peak originating from the matrix was observed by differential scanning calorimetry, and the peak of the endothermic peak showing the maximum heat flux was observed to be above 108 °C.

[0012] [3] According to the light-absorbing anisotropic film described in [1] or [2], wherein, The absolute value of the difference between the logP value of the dichroic substance and the logP value of the matrix is ​​4.8 to 5.6.

[0013] [4] The light-absorbing anisotropic film according to any one of [1] to [3], wherein, The angle θ between the transmittance central axis of the light-absorbing anisotropic film and the normal direction of the surface of the light-absorbing anisotropic film is greater than 0° and less than 45°.

[0014] [5] The light-absorbing anisotropic film according to any one of [1] to [4], wherein, A dichroic substance is a mixture containing at least a pigment compound having a maximum absorption wavelength in the range of 380 nm to less than 455 nm, a pigment compound having a maximum absorption wavelength in the range of 455 nm to less than 560 nm, and a pigment compound having a maximum absorption wavelength in the range of 560 nm to less than 700 nm.

[0015] [6] A laminate having any one of [1] to [5] light-absorbing anisotropic film.

[0016] Invention Effects According to the present invention, it is possible to provide a light-absorbing anisotropic film with low haze value and high orientation degree, and a laminate having the light-absorbing anisotropic film. Attached Figure Description

[0017] Figure 1 This is a schematic diagram illustrating an example of a head-mounted display having the laminate of the present invention (hereinafter also simply referred to as "the head-mounted display of the present invention").

[0018] Figure 2 This is a schematic diagram illustrating an example of the structure of a light guide plate used in AR (Augumented Reality) glasses.

[0019] Figure 3 This is a schematic diagram showing a top view of the evaluation system for the head-mounted display of the present invention.

[0020] Figure 4 The DSC curve represents the light-absorbing anisotropic film prepared in Example 1.

[0021] Figure 5 The DSC curves of the anisotropic absorber film prepared in Comparative Example 1 are shown.

[0022] Figure 6 The DSC curves represent the matrix-only components of the anisotropic films produced in Example 1 and Comparative Example 1. Detailed Implementation

[0023] The present invention will now be described in detail.

[0024] The following description of the constituent elements is based on a representative embodiment of the present invention, but the present invention is not limited to this embodiment.

[0025] In addition, in this specification, the numerical range indicated by “~” represents the range including the values ​​recorded before and after “~” as the lower limit and upper limit values.

[0026] Furthermore, the upper or lower limit value recorded within a certain numerical range specified in this specification can be replaced with the upper or lower limit value within other numerical ranges specified in this specification. Also, the upper or lower limit value recorded within a certain numerical range specified in this specification can be replaced with the value shown in the embodiment.

[0027] Furthermore, in this specification, for each component, one substance corresponding to that component may be used alone, or two or more substances may be used in combination. Where two or more substances are used in combination for each component, the content of that component, unless otherwise specified, refers to the total content of all substances used in combination.

[0028] Furthermore, in this specification, "(meth)acrylate" is a designation for "acrylate" or "methacrylate", "(meth)acrylic acid" is a designation for "acrylic acid" or "methacrylic acid", and "(meth)acryloyl" is a designation for "acryloyl" or "methacryloyl".

[0029] [Light-absorbing anisotropic membrane] The light-absorbing anisotropic film of the present invention is a light-absorbing anisotropic film containing a dichroic substance and a matrix composed of all components other than the dichroic substance.

[0030] Furthermore, the light-absorbing anisotropic film of the present invention is a light-absorbing anisotropic film in which at least one endothermic peak originating from a dichroic substance is observed by differential scanning calorimetry, and all the observed endothermic peaks originating from the dichroic substance (in the case of only one endothermic peak being observed, it is considered as one observed endothermic peak) are endothermic peaks with an endothermic onset temperature of 105°C or higher.

[0031] Here, regarding differential scanning calorimetry, a differential scanning calorimeter (e.g., the X-DSC7000 manufactured by Seiko Instruments Inc.) is used. A sample of 3.0 mg ± 0.3 mg of anisotropic absorbance film is placed in an aluminum sample dish, and the measurement is performed under a nitrogen atmosphere while the temperature is increased from room temperature to 140 °C at a rate of 5 °C / min.

[0032] Furthermore, the endothermic onset temperature refers to the temperature at which the vertical axis is set as the heat flow (hereinafter, in...). Figures 4-6 This is referred to as "Heat Flow" in the text. In a differential scanning calorimetry (DSC) curve (where the horizontal axis is set to temperature), the temperature at which 6% of the heat flow is displayed when the heat flow at the peak of the endothermic peak is set to 100% is the temperature below the peak temperature of the endothermic peak. Specifically, for example... Figure 4 As shown, in Example 1 described later, when the heat flux at the peak of the endothermic peak is set to 100%, the temperature showing a 6% heat flux is 108°C, but as... Figure 5 As shown, in Comparative Example 1 described later, when the heat flux at the peak of the endothermic peak was set to 100%, the temperature showing a heat flux of 6% was 101°C.

[0033] In this invention, endothermic peaks originating from dichroic materials are observed by DSC, and the endothermic onset temperature of all observed endothermic peaks reaches 105°C or higher. The light-absorbing anisotropic film has low haze and high orientation.

[0034] The reasons for this effect are not yet clear, but the inventor speculates as follows.

[0035] First, it is believed that dichroic substances in light-absorbing anisotropic films constitute various aggregates (e.g., crystals, eutectics, condensates, etc.).

[0036] Therefore, the endothermic onset temperature of the endothermic peak originating from dichroic substances corresponds to the endothermic reaction of the most unstable aggregate. A high endothermic onset temperature indicates that even the most unstable aggregate has relatively high stability. Moreover, it can be said that the degree of stability can be used as an indicator of the strength of the attraction between dichroic substances or the orderliness of their orientation.

[0037] Therefore, it is believed that the anisotropic films with an endothermic onset temperature of 105℃ or higher for all endothermic peaks originating from dichroic substances have higher orientation and are more likely to form ideal microcrystals with fewer coarse particles, thus resulting in lower haze values.

[0038] As described above, the endothermic onset temperature of all endothermic peaks of the light-absorbing anisotropic film of the present invention derived from dichroic substances reaches 105°C or higher, but preferably 108°C or higher, and the upper limit of the endothermic onset temperature is preferably 140°C or lower.

[0039] Considering the need for lower haze values, the light-absorbing anisotropic film of the present invention is preferably a light-absorbing anisotropic film in which the peak (hereinafter also referred to as the "maximum endothermic peak temperature of the matrix") of the endothermic peak that exhibits the maximum heat flux (i.e., in the case of multiple observed endothermic peaks, it refers to the endothermic peak exhibiting the maximum heat flux among all endothermic peaks; in the case of only one observed endothermic peak, it 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. Furthermore, the upper limit of this temperature range is preferably 140°C or lower.

[0040] Here, it is possible to determine whether the observed endothermic peak originates from a dichroic substance or from the matrix.

[0041] First, when the raw materials constituting the light-absorbing anisotropic film are available, as in the embodiments described later, a film composed of raw materials other than the dichroic substance, i.e., a film composed only of a matrix, is prepared, and its DSC is measured. The DSC measurement results are compared with those of the light-absorbing anisotropic film containing the dichroic substance and the matrix, and the endothermic peak of the matrix and the endothermic peak of the dichroic substance can be distinguished.

[0042] Furthermore, when the endothermic peak of the matrix overlaps with the endothermic peak of the dichroic substance, it is possible to prepare other matrices with endothermic peaks that are sufficiently lower than those of the dichroic substance (endothermic peaks do not overlap), fabricate an anisotropic film composed of the matrix and the dichroic substance, and measure the endothermic peak of the dichroic substance.

[0043] On the other hand, when only raw materials that have become anisotropic absorbers are available, DSC measurements are performed on anisotropic absorbers made from samples that have been finely pulverized (using solvents to remove dichroic substances) and powders that have not been extracted and remain only as matrix. By comparing these results with the DSC measurements of the anisotropic absorbers before extraction (i.e., the obtained ones), the endothermic peaks of the matrix and the endothermic peaks of the dichroic substances can be distinguished separately.

[0044] Furthermore, similarly, when the endothermic peak of the matrix overlaps with that of the dichroic substance, it is possible to prepare other matrices with endothermic peaks sufficiently lower than those of the dichroic substance, fabricate an anisotropic absorbance film composed of this matrix and the dichroic substance obtained through the above extraction, and measure the endothermic peak of the dichroic substance. Alternatively, for pigments obtained through extraction, the molecular structure can be identified using known methods such as nuclear magnetic resonance (NMR), infrared absorption spectrometry (IR), and mass spectrometry, to synthesize dichroic substances with the same molecular structure, combine them with a matrix to fabricate anisotropic absorbance films, and measure the endothermic peak using DSC.

[0045] Considering the need for higher orientation, in the light-absorbing anisotropic film of the present invention, the absolute value of the difference between the logP value of the dichroic material and the logP value of the matrix (hereinafter also simply referred to as "ΔlogP value") is preferably 4.8 to 5.8.

[0046] Here, the logP value is an indicator of the hydrophilicity and hydrophobicity of a chemical structure, sometimes referred to as the hydrophilic-hydrophobic parameter. The logP value can be calculated using software such as ChemBioDraw Ultra or HSPiP (Ver. 4.1.07). It can also be experimentally determined using methods such as those described in OECD Guidelines for the Testing of Chemicals, Section 1, Test No. 117. In this invention, unless otherwise specified, the value calculated by inputting the structural formula of the compound into HSPiP (Ver. 4.1.07) is used as the logP value.

[0047] Furthermore, regarding the logP value of the matrix, the logP value can be calculated for each component other than the dichroic substance, and calculated as a weighted average based on the addition ratio on a mass basis. Additionally, when the liquid crystal composition forming the light-absorbing anisotropic film contains a low-molecular-weight liquid crystal compound, the logP value of the component originating from the low-molecular-weight liquid crystal compound contained in the light-absorbing anisotropic film can be set as the logP value of the low-molecular-weight liquid crystal compound contained in the liquid crystal composition.

[0048] In the light-absorbing anisotropic film of the present invention, considering the advantages of low haze and high orientation, the angle θ (hereinafter also simply referred to as "transmittance center axis angle θ") between the transmittance central axis of the light-absorbing anisotropic film and the normal direction of the surface of the light-absorbing anisotropic film is preferably 0° or more and 45° or less, more preferably 0° or more and less than 45°, further preferably 0° or more and less than 35°, and especially preferably 0° or more and less than 35°.

[0049] Here, the transmittance center axis of the light-absorbing anisotropic film indicates the direction showing the highest transmittance when measuring transmittance by changing the tilt angle (polar angle) and tilt direction (azimuth angle) relative to the normal direction of the light-absorbing anisotropic film surface (main surface).

[0050] Specifically, the Mueller matrix at a wavelength of 550 nm was measured using an AxoScan (OPMF-2, manufactured by Axometrics). More specifically, during the measurement, the azimuth angle at which the transmittance central axis is tilted was initially found. Then, within a plane containing the normal direction of the anisotropic absorber film along that azimuth angle (a plane containing the transmittance central axis and orthogonal to the film surface), the angle relative to the normal direction of the anisotropic absorber film surface, i.e., the polar angle, was changed in 1° increments between -70° and 70°, while simultaneously measuring the Mueller matrix at a wavelength of 550 nm, and the transmittance of the anisotropic absorber film was derived. The direction with the highest transmittance was then taken as the transmittance central axis.

[0051] In addition, the transmittance center axis refers to the direction of the absorption axis (long axis direction of the molecule) of the dichroic substance contained in the anisotropic absorber film.

[0052] The light-absorbing anisotropic film of the present invention is preferably a film formed by fixing the orientation state of a liquid crystal composition containing a liquid crystal compound and a dichroic substance.

[0053] The components contained in the liquid crystal composition are described in detail below.

[0054] In addition, the components described below are basically those that are also present in the light-absorbing anisotropic film. However, for the sake of immobilization of orientation state, components with crosslinking groups (including polymerizable groups) are included in the light-absorbing anisotropic film as crosslinked (polymerized) components.

[0055] <Liquid Crystal Compounds> The above-mentioned liquid crystal composition contains a liquid crystal compound. Therefore, it is possible to suppress the precipitation of dichroic substances and to orient the dichroic substances with a higher degree of orientation.

[0056] As the liquid crystal compound, either a high-molecular-weight liquid crystal compound or a low-molecular-weight liquid crystal compound can be used. From the viewpoint of improving the degree of orientation, a high-molecular-weight liquid crystal compound is preferred. Furthermore, both high-molecular-weight liquid crystal compounds and low-molecular-weight liquid crystal compounds can be used together as the liquid crystal compound.

[0057] Here, "polymer liquid crystal compound" refers to a liquid crystal compound that has repeating units in its chemical structure.

[0058] Furthermore, "low molecular weight liquid crystal compounds" refers to liquid crystal compounds that do not have repeating units in their chemical structure.

[0059] Examples of polymeric liquid crystal compounds include, for example, the thermotropic liquid crystal polymer described in Japanese Patent Application Publication No. 2011-237513, and the polymeric liquid crystal compounds described in paragraphs

[0012] to

[0042] of International Publication No. 2018 / 199096.

[0060] As a low-molecular-weight liquid crystal compound, examples include the liquid crystal compounds described in paragraphs

[0072] to

[0088] of Japanese Patent Application Publication No. 2013-228706, among which, liquid crystal compounds exhibiting smectic properties are preferred.

[0061] Examples of such liquid crystal compounds include those described in paragraphs

[0019] to

[0140] of International Publication No. 2022 / 014340, which are incorporated herein by reference.

[0062] Furthermore, the liquid crystal compound is preferably a liquid crystal compound that does not exhibit dichroism in the visible light region.

[0063] The content of the liquid crystal compound is preferably 25 to 2000 parts by mass relative to 100 parts by mass of the dichroic material described later, more preferably 100 to 1300 parts by mass, and even more preferably 200 to 900 parts by mass. By keeping the content of the liquid crystal compound within the above range, the orientation degree of the dichroic material is further improved.

[0064] The liquid crystal compound may contain a single compound or two or more compounds. When the liquid crystal compound contains two or more compounds, the content of the liquid crystal compound mentioned above represents the total content of the liquid crystal compounds.

[0065] <Dichromatic substances> The above liquid crystal composition contains a dichroic substance.

[0066] Here, dichroism refers to pigments whose absorbance varies depending on the direction.

[0067] Furthermore, dichroic materials may or may not exhibit liquid crystal properties.

[0068] There are no particular limitations on dichroic substances. Examples include visible light absorbing substances (dichroic pigments), luminescent substances (fluorescent substances, phosphorescent substances), ultraviolet light absorbing substances, infrared light absorbing substances, nonlinear optical substances, carbon nanotubes, and inorganic substances (e.g., quantum rods). Previously known dichroic substances (dichroic pigments) can be used.

[0069] Specifically, examples include paragraphs

[0067] to

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

[0008] to

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

[0008] to

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

[0045] to

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

[0012] to

[0029] of Japanese Patent Application Publication No. 2013-101328, paragraphs

[0009] to

[0017] of Japanese Patent Application Publication No. 2013-37353, and paragraphs

[0051] to

[0065] of Japanese Patent Application Publication No. 2013-37353. Japanese Patent Application Publication No. 2012-63387, paragraphs

[0049] to

[0073] ; Japanese Patent Application Publication No. Hei 11-305036, paragraphs

[0016] to

[0018] ; Japanese Patent Application Publication No. 2001-133630, paragraphs

[0009] to

[0011] ; Japanese Patent Application Publication No. 2011-215337, paragraphs

[0030] to

[0169] ; Japanese Patent Application Publication No. 2010-106242, paragraphs

[0021] to

[0075] ; Japanese Patent Application Publication No. 2010-215846, paragraphs

[0011] to

[0025] ; Japanese Patent Application Publication No. 2011-048311, paragraphs

[0017] to

[0069] ; Japanese Patent Application Publication No. 2011-2 Paragraphs

[0013] to

[0133] of Japanese Patent Application Publication No. 13610, paragraphs

[0074] to

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

[0005] to

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

[0014] to

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

[0014] to

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

[0005] to

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

[0008] to

[0062] of International Publication No. 2016 / 136561, and International Publication No. 2017 / 154835. Paragraphs

[0014] to

[0033] , paragraphs

[0014] to

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

[0013] to

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

[0014] to

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

[0021] to

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

[0043] to

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

[0043] to

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

[0050] to

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

[0015] to

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

[0070] As a dichroic substance, a dichroic azo dye compound is preferred.

[0071] Dichroic azo dye compounds refer to azo dye compounds whose absorbance varies depending on the direction. Dichroic azo dye compounds may or may not exhibit liquid crystal properties. When a dichroic azo dye compound exhibits liquid crystal properties, it can exhibit either nematic or smectic properties. The preferred temperature range for displaying the liquid crystal phase is room temperature (approximately 20–28°C) to 300°C, and more preferably 50–200°C from the viewpoint of processability and manufacturing suitability.

[0072] In this invention, from the viewpoint of hue adjustment, as a dichroic material, it is preferable to use a mixture containing a pigment compound (especially a dichroic azo pigment compound) that has a maximum absorption wavelength in the range of wavelengths above 380 nm and below 455 nm, a pigment compound (especially a dichroic azo pigment compound) that has a maximum absorption wavelength in the range of wavelengths above 455 nm and below 560 nm, and a pigment compound (especially a dichroic azo pigment compound) that has a maximum absorption wavelength in the range of wavelengths above 560 nm and below 700 nm.

[0073] In particular, in this invention, as a pigment compound having a large absorption wavelength in the range of wavelengths above 380 nm and below 455 nm, it is preferable to contain a dichroic azo pigment compound represented by the following formula (1).

[0074] [Chemical Formula 1] In the above formula (1), A and B independently represent crosslinking groups.

[0075] In the above formula (1), a and b independently represent 0 or 1, respectively. Where a+b≥1.

[0076] In equation (1) above, when a=0, L1 represents a monovalent substituent, and when a=1, L1 represents a single bond or a divalent linker. Furthermore, when b=0, L2 represents a monovalent substituent, and when b=1, L2 represents a single bond or a divalent linker.

[0077] In the above formula (1), Ar1 represents an aromatic hydrocarbon group or heterocyclic group with a valence of (n1+2), Ar2 represents an aromatic hydrocarbon group or heterocyclic group with a valence of (n2+2), and Ar3 represents an aromatic hydrocarbon group or heterocyclic group with a valence of (n3+2). In the above formula (1), R1, R2 and R3 independently represent monovalent substituents. When n1≥2, multiple R1s can be the same or different. When n2≥2, multiple R2s can be the same or different. When n3≥2, multiple R3s can be the same or different.

[0078] In equation (1) above, k represents an integer from 1 to 4. When k ≥ 2, multiple Ar2 can be the same or different from each other, and multiple R2 can be the same or different from each other.

[0079] In the above formula (1), n1, n2 and n3 independently represent integers from 0 to 4, where n1+n2+n3≥0 when k=1 and n1+n2+n3≥1 when k≥2.

[0080] Furthermore, for explanations and examples of the symbols in the above formula (1), please refer to the contents described in paragraphs

[0013] to

[0038] of International Publication No. 2017 / 195833, which are incorporated herein by reference.

[0081] In this invention, considering the ease of observing at least one endothermic peak originating from a dichroic substance with an endothermic onset temperature of 105°C or higher, the dichroic azo dye compound represented by the above formula (1) is preferably a compound in which: a and b in the above formula (1) both represent 1, k represents 1 or 2, n1 and n3 both represent 1, n2 represents 0 or 1, Ar1 to Ar3 in the above formula (1) both represent phenylene, R1 and R3 both represent halogen atoms (especially chlorine) located at the ortho position of the azo bond (-N=N-), when n2 is 1, R2 represents alkyl (especially methyl), L1 and L2 both represent alkylene with 2 to 6 carbon atoms, and A and B both represent (meth)acryloyloxy.

[0082] The content of dichroic substances contained in the aforementioned anisotropic light-absorbing film is not particularly limited. However, based on the reason that the orientation degree of the formed anisotropic light-absorbing film increases, it 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 anisotropic light-absorbing film. In addition, when multiple dichroic substances are used together, it is preferable that the total amount of the multiple dichroic substances is within the above-mentioned range.

[0083] Furthermore, based on the reason that the orientation degree of the formed anisotropic light-absorbing film increases, the content of dichroic substances contained in the aforementioned anisotropic light-absorbing film is preferably 20 to 650 mg / cm³. 3 Preferably 25–500 mg / cm³ 3 More preferably 30–200 mg / cm³ 3More preferably 40–150 mg / cm³ 3 Furthermore, when using multiple dichroic substances together, it is preferable that the total amount of the multiple dichroic substances is within the above-mentioned range.

[0084] Here, the content of dichroic substances (mg / cm³) 3 The solution obtained by dissolving a laminate with anisotropic absorbance film using high-performance liquid chromatography (HPLC) or by solvent impregnation of the laminate can be used, but is not limited to the methods described above. Furthermore, quantification can be performed using dichroic substances contained in the anisotropic absorbance film as standard samples.

[0085] As an example of a method for calculating the content of dichroic substances, the following method can be used: the volume is calculated by multiplying the thickness of the light-absorbing anisotropic film obtained from a microscopic image of the cross-section of the laminate with the area of ​​the optical laminate used to measure the amount of pigment, and the pigment content is calculated by dividing the amount of pigment determined by HPLC by this volume.

[0086] Vertical Orientation Agent The liquid crystal composition described above preferably contains a vertical alignment agent.

[0087] Here, "vertical alignment agent" refers to an additive that functions to orient the liquid crystal compound in the vertical direction relative to the principal plane of the light-absorbing anisotropic film. Furthermore, "orientation in the vertical direction" does not strictly require orientation at 90°, but rather indicates orientation at 70 to 110°.

[0088] Examples of vertical alignment agents include ionic vertical alignment agents and vertical alignment agents with borate groups. It is preferable to use both ionic vertical alignment agents and vertical alignment agents with borate groups.

[0089] As an ionic vertical orientation agent, onium compounds represented by the following formula (B1) are preferably examples.

[0090] [Chemical Formula 2] In the above formula (B1), ring A represents a quaternary ammonium ion composed of a nitrogen-containing heterocycle.

[0091] Furthermore, X represents an anion.

[0092] Furthermore, L 1 This indicates a divalent linker.

[0093] Furthermore, L 2 This indicates a single bond or a divalent linker.

[0094] Furthermore, Y 1This indicates a divalent linker with a 5- or 6-membered ring as part of the structure.

[0095] Furthermore, Z indicates that an alkylene group with 2 to 20 carbon atoms serves as a divalent linker in the partial structure.

[0096] Furthermore, P 1 and P 2 Each of these represents a monovalent substituent that has a polymerizable olefinic unsaturated bond.

[0097] Ring A represents a quaternary ammonium ion composed of a nitrogen-containing heterocycle. Examples of ring A include pyridine rings, methylpyridine rings, 2,2'-bipyridine rings, 4,4'-bipyridine rings, 1,10-phenanthroline rings, quinoline rings, oxazole rings, thiazole rings, imidazole rings, pyrazine rings, triazole rings, tetrazolium rings, etc., with quaternary imidazole rings and quaternary pyridinium rings being preferred.

[0098] X represents an anion. Examples of X include halide anions (e.g., fluoride, chloride, bromide, iodide, etc.), sulfonate ions (e.g., methanesulfonate, trifluoromethanesulfonate, methyl sulfate, vinylsulfonate, allylsulfonate, p-toluenesulfonate, p-chlorobenzenesulfonate, p-vinylbenzenesulfonate, 1,3-benzenedisulfonate, 1,5-naphthalenedisulfonate, 2,6-naphthalenedisulfonate, etc.), sulfate ions, carbonate ions, nitrate ions, thiocyanate ions, perchlorate ions, tetrafluoroborate ions, picric acid ions, acetate ions, benzoate ions, p-vinylbenzoate ions, formate ions, trifluoroacetate ions, phosphate ions (e.g., hexafluorophosphate ions), and hydroxide ions. Halogen anions, sulfonate ions, and hydroxide ions are preferred. Furthermore, chloride ions, bromide ions, iodide ions, methanesulfonate ions, vinylsulfonate ions, p-toluenesulfonate ions, and p-vinylbenzenesulfonate ions are particularly preferred.

[0099] L 1 Indicates a divalent linker. As L 1 Examples can be categorized as divalent linkages with 1 to 20 carbon atoms, consisting of combinations of alkylene, -O-, -S-, -CO-, -SO2-, -NRa- (where Ra is an alkyl or hydrogen atom with 1 to 5 carbon atoms), alkenyl, ynylene, or arylene. 1 Preferably, the carbon atoms are -AL-, -O-AL-, -CO-O-AL-, or -O-CO-AL-, with 1 to 10 carbon atoms; more preferably, -AL- or -O-AL- with 1 to 10 carbon atoms; and most preferably, -AL- or -O-AL- with 1 to 5 carbon atoms. Additionally, AL represents an alkylene group.

[0100] L2 represents a single bond or a divalent linker. As L... 2 Examples include divalent linkers with 1 to 10 carbon atoms, composed of combinations of alkylene, -O-, -S-, -CO-, -SO2-, -NRa- (where Ra is an alkyl or hydrogen atom with 1 to 5 carbon atoms), alkenyl, ynylene, or arylene groups; single bonds; -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-O-AL-CO-O-; -O-CO-AL-O-; -O-CO-AL-CO-O-; -O-CO-AL-CO-O-; etc. Additionally, AL represents alkylene. L2 is preferably a single bond with 1 to 10 carbon atoms, such as -AL-, -O-AL-, or -NRa-AL-O-; more preferably a single bond with 1 to 5 carbon atoms, such as -AL-, -O-AL-, or -NRa-AL-O-; and most preferably a single bond with 1 to 5 carbon atoms, such as -O-AL- or -NRa-AL-O-.

[0101] Y 1 This indicates a divalent linker with a 5- or 6-membered ring as a partial structure. As Y... 1 Examples of heterocyclic rings include cyclohexyl rings, aromatic rings, and heterocyclic rings. Aromatic rings include, for example, benzene rings, indene rings, naphthalene rings, fluorene rings, phenanthrene rings, anthracene rings, biphenyl rings, and pyrene rings, with benzene rings, biphenyl rings, and naphthalene rings being particularly preferred. Heteroatoms constituting the heterocyclic ring are preferably nitrogen atoms, oxygen atoms, and sulfur atoms, and examples include furan rings, thiophene rings, pyrrole rings, pyrrolin rings, pyrrolidinyl rings, oxazole rings, isoxazole rings, thiazolium rings, isothiazole rings, imidazole rings, imidazoleline rings, imidazolealidyl rings, pyrazoline rings, triazole rings, furazonium rings, tetrazolium rings, pyran rings, dioxane rings, dithiohexacyclohexane rings, thipenan rings, pyridine rings, piperidine rings, oxazine rings, morpholine rings, thiazine rings, pyridazine rings, pyrimidine rings, pyrazine rings, piperazine rings, and triazine rings. The heterocyclic ring is preferably a 6-membered ring. Having Y 1 The 5- or 6-membered rings represented as divalent linkers in the partial structure may also have substituents (e.g., the substituent W mentioned above).

[0102] Y 1 The divalent linker represented is preferably a divalent linker having two or more 5- or 6-membered rings, and more preferably a structure having two or more rings connected by the linker. An example of a linker can be L... 1 and L 2 Examples of the connecting groups represented are -C≡C-, -CH=CH-, -CH=N-, -N=CH-, -N=N-, etc.

[0103] Z has an alkylene group having 2 to 20 carbon atoms as a partial structure, representing a divalent linker composed of a combination of -O-, -S-, -CO-, and -SO2-, and the alkylene group may have substituents. Examples of the aforementioned divalent linker include alkyleneoxy groups and polyalkyleneoxy groups. The alkylene group represented by Z more preferably has 2 to 16 carbon atoms, further preferably 2 to 12, and particularly preferably 2 to 8.

[0104] P1 and P2 each independently represent a monovalent substituent having a polymerizable olefinic unsaturated group. Examples of the monovalent substituents having polymerizable olefinic unsaturated groups described above include the following formulas (M-1) to (M-8). That is, the monovalent substituent having a polymerizable olefinic unsaturated group can be a substituent consisting only of vinyl groups, as in (M-8).

[0105] [Chemical Formula 3] In formulas (M-3) and (M-4), R represents a hydrogen atom or an alkyl group, preferably a hydrogen atom or a methyl group. In formulas (M-1) to (M-8) above, (M-1), (M-2), and (M-8) are preferred, more preferably (M-1) or (M-8). In particular, (M-1) is preferred as P1. Furthermore, (M-1) or (M-8) is preferred as P2. In compounds where ring A is a quaternary imidazolium ion, P2 is preferably (M-8) or (M-1), and in compounds where ring A is a quaternary pyridinium ion, P2 is preferably (M-1).

[0106] Examples of onium compounds represented by the above formula (B1) include the onium salts described in paragraphs 0052 to 0058 of Japanese Patent Application Publication No. 2012-208397, the onium salts described in paragraphs 0024 to 0055 of Japanese Patent Application Publication No. 2008-026730, and the onium salts described in Japanese Patent Application Publication No. 2002-37777.

[0107] As ionic vertical alignment agents, in addition to the onium compounds represented by the above formula (B1), examples of ionic vertical alignment agents described in paragraphs

[0017] to

[0029] of Japanese Patent Application Publication No. 2020-181150 can be cited.

[0108] As a vertical orientation agent having a boric acid group, a boric acid compound represented by the following formula (B2) is preferably exemplified.

[0109] [Chemical Formula 4] In (B2) above, R 1 and R 2Each can independently represent a hydrogen atom, an aliphatic hydrocarbon group that may have substituents, an aryl group that may have substituents, or a heterocyclic group that may have substituents.

[0110] Furthermore, R 3 Indicates a substituent.

[0111] As R 1 and R 2 Examples of aliphatic hydrocarbon groups represented in one manner include substituted or unsubstituted straight-chain or branched alkyl groups (e.g., methyl, ethyl, isopropyl, etc.) having 1 to 20 carbon atoms, substituted or unsubstituted cyclic alkyl groups (e.g., cyclohexyl, etc.) having 3 to 20 carbon atoms, and alkenyl groups (e.g., vinyl, etc.) having 2 to 20 carbon atoms.

[0112] Furthermore, as R 1 and R 2 Examples of aryl groups represented in one manner include substituted or unsubstituted phenyl groups (e.g., phenyl, tolyl, etc.) with 6 to 20 carbon atoms, and substituted or unsubstituted naphthyl groups with 10 to 20 carbon atoms.

[0113] Furthermore, as R 1 and R 2 The heterocyclic group represented in one manner can be, for example, a group containing at least one heteroatom (e.g., nitrogen atom, oxygen atom, sulfur atom, etc.) of a substituted or unsubstituted 5- or 6-membered ring, specifically, pyridyl, imidazolyl, furanyl, piperidinyl, morpholinyl, etc.

[0114] R 1 and R 2 They can be connected to form a loop, such as R. 1 and R 2 The isopropyl groups can be linked to form a 4,4,5,5-tetramethyl-1,3,2-dioxaborane ring.

[0115] R 1 and R 2 Preferably, it is a hydrogen atom, a straight-chain or branched alkyl group having 1 to 3 carbon atoms, and the alkyl group being linked together to form a ring, more preferably a hydrogen atom.

[0116] As R 3 The substituents indicated are preferably substituents containing functional groups capable of bonding with (meth)acryloyl groups.

[0117] Here, examples of functional groups capable of bonding with (meth)acryloyl groups include vinyl, acrylate, methacrylate, acrylamide, styrene, vinyl ketone, butadiene, vinyl ether, ethylene oxide, aziridinyl, and oxetane, among which vinyl, acrylate, methacrylate, styrene, ethylene oxide, or oxetane are preferred, and vinyl, acrylate, acrylamide, or styrene are more preferred.

[0118] As R 3 Preferably, it is a substituted or unsubstituted aliphatic hydrocarbon group, aryl group or heterocyclic group having a functional group capable of bonding with (meth)acryloyl group.

[0119] Examples of aliphatic hydrocarbon groups include substituted or unsubstituted straight-chain or branched alkyl groups with 1 to 30 carbon atoms (e.g., methyl, ethyl, isopropyl, n-propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, hexadecyl, octadecyl, eicosyl, isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl, 1-methylbutyl, isohexyl, 2-methylhexyl, etc.), substituted or unsubstituted cyclic alkyl groups with 3 to 20 carbon atoms (e.g., cyclopentyl, cyclohexyl, 1-adamantyl, 2-norbornyl, etc.), and alkenyl groups with 2 to 20 carbon atoms (e.g., vinyl, 1-propenyl, 1-butenyl, 1-methyl-1-propenyl, etc.).

[0120] Examples of aryl groups include substituted or unsubstituted phenyl groups with 6 to 50 carbon atoms (e.g., phenyl, tolyl, styryl, 4-benzoyloxyphenyl, 4-phenoxycarbonylphenyl, 4-biphenyl, 4-(4-octyloxybenzoyloxy)phenoxycarbonylphenyl, etc.) and substituted or unsubstituted naphthyl groups with 10 to 50 carbon atoms (e.g., unsubstituted naphthyl groups, etc.).

[0121] As a heterocyclic group, it is, for example, a substituted or unsubstituted 5- or 6-membered ring group containing at least one heteroatom (e.g., nitrogen atom, oxygen atom, sulfur atom, etc.), such as pyrrole, furan, thiophene, pyrazole, imidazole, triazole, oxazole, isoxazole, oxadiazole, thiazole, thiadiazole, indole, carbazole, benzofuran, dibenzofuran, thiain, dibenzothiophene, indazole benzimidazole, anthranilic acid, benzisoxazole, benzoxazole, benzothiazole, purine, pyridine, pyridazine, pyrimidine, pyrazine, triazine, quinoline, acridine, isoquinoline, phthalazine, quinazoline, quinoxaline, naphthidine, phenanthroline, pteridine, morpholine, piperidine, etc.

[0122] As a boric acid compound represented by the above formula (B2), for example, a boric acid compound represented by general formula (I) described in paragraphs 0023 to 0032 of Japanese Patent Application Publication No. 2008-225281 can be cited.

[0123] The compounds represented by the above formula (B2) are also preferably the compounds exemplified below.

[0124] [Chemical Formula 5] When the liquid crystal composition contains a vertical alignment agent, the content of the vertical alignment agent relative to the content of the liquid crystal compound 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 per 100 parts by mass.

[0125] The vertical alignment agent may consist of one type or two or more types. When the liquid crystal compound contains two or more types, the content of the vertical alignment agent mentioned above represents the total content of the vertical alignment agents.

[0126] <Solvent> From the viewpoint of operability, the above-mentioned liquid crystal composition preferably contains a solvent.

[0127] Examples of solvents include ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, acetylacetone, etc.), ethers (e.g., dioxane, tetrahydrofuran, tetrahydropyran, dioxolane, tetrahydrofurfuryl alcohol, cyclopentylmethyl ether, dibutyl ether, etc.), aliphatic hydrocarbons (e.g., hexane, etc.), alicyclic hydrocarbons (e.g., cyclohexane, etc.), aromatic hydrocarbons (e.g., benzene, toluene, xylene, tetrahydronaphthalene, trimethylbenzene, etc.), carbon halogens (e.g., dichloromethane, chloroform, dichloroethane, dichlorobenzene, 1,1,2,2-tetrachloroethane, chlorotoluene, etc.), and esters (e.g., methyl acetate, ethyl acetate, butyl acetate, diethyl carbonate, ethyl acetoacetate, n-amyl acetate, ethyl benzoate, benzyl benzoate, butylcarbamate, etc.). Organic solvents such as ethylene glycol acetate, diethylene glycol monoethyl ether acetate, isoamyl acetate, etc., alcohols (e.g., 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, etc.), phenols (e.g., phenol, cresol, etc.), cellosolvers (e.g., methyl cellosolve, ethyl cellosolve and 1,2-dimethoxyethane, etc.), cellosolve acetates, sulfoxides (e.g., dimethyl sulfoxide, etc.), amides (e.g., dimethylformamide and dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone, 1,3-dimethyl-2-imidazolinone, etc.), and heterocyclic compounds (e.g., pyridine, 2,6-dimethylpyridine, etc.) as well as water.

[0128] These solvents can be used alone or in combination of two or more.

[0129] When the above liquid crystal composition contains a solvent, the solvent content relative to the total mass (100% by mass) of the liquid crystal composition is preferably 60 to 99.5% by mass, more preferably 70 to 99% by mass, and especially preferably 75 to 98% by mass.

[0130] <Polymerization Initiator> The above-mentioned liquid crystal composition may contain a polymerization initiator.

[0131] There are no particular limitations on the polymerization initiator, but it is preferred to use a photosensitive compound, i.e., a photopolymerization initiator.

[0132] As photopolymerization initiators, a wide variety of compounds can be used without particular limitations. Examples of photopolymerization initiators include α-carbonyl compounds (as described in U.S. Patent Nos. 2,367,661 and 2,367,670), azobin ethers (as described in U.S. Patent No. 2,448,828), α-hydrocarbon-substituted aromatic azobin compounds (as described in U.S. Patent No. 2,722,512), polynuclear quinone compounds (as described in U.S. Patent Nos. 3,046,127 and 2,951,758), and combinations of triarylimidazolium dimers and p-aminophenyl ketones (as described in U.S. Patent No. 3,549,367). Specifications), acridine and phenazine compounds (Japanese Patent Application Publication No. 60-105667 and US Patent No. 4239850), oxadiazole compounds (US Patent No. 4212970), o-acyl oxime compounds (Japanese Patent Application Publication No. 2016-27384

[0065] ), and acylphosphine oxide compounds (Japanese Patent Application Publication No. 63-40799, Japanese Patent Application Publication No. 5-29234, Japanese Patent Application Publication No. 10-95788, and Japanese Patent Application Publication No. 10-29997), etc.

[0133] Commercially available products can also be used as photopolymerization initiators, such as IRGACURE-184, IRGACURE-907, IRGACURE-369, IRGACURE-651, IRGACURE-819, IRGACURE-OXE-01 and IRGACURE-OXE-02 manufactured by BASF.

[0134] When the above liquid crystal composition contains a polymerization initiator, the content of the polymerization initiator relative to the total solid content of the liquid crystal composition is preferably 0.01 to 30% by mass, more preferably 0.1 to 15% by mass.

[0135] <surfactants> The liquid crystal composition described above may contain a surfactant.

[0136] There are no particular restrictions on the surfactant used; high molecular weight surfactants and low molecular weight surfactants can be used, and compounds described in paragraphs

[0253] to

[0293] of Japanese Patent Application Publication No. 2011-237513 can be used.

[0137] Furthermore, as a surfactant, fluoro(meth)acrylate polymers and silicon polymers described in Japanese Patent Application Publication No. 2007-272185,

[0018] to

[0043] , etc., can also be used.

[0138] Furthermore, as a surfactant, compounds described in paragraphs

[0079] to

[0102] of Japanese Patent Application Publication No. 2007-069471, polymerizable liquid crystal compounds represented by formula (4) described in Japanese Patent Application Publication No. 2013-047204 (especially compounds described in paragraphs

[0020] to

[0032] ), polymerizable liquid crystal compounds represented by formula (4) described in Japanese Patent Application Publication No. 2012-211306 (especially compounds described in paragraphs

[0022] to

[0029] ), and liquid crystal oriented compounds represented by formula (4) described in Japanese Patent Application Publication No. 2002-129162 can also be used. Accelerators (especially compounds described in paragraphs

[0076] to

[0078] and

[0082] to

[0084] ), compounds represented by formulas (4), (II) and (III) as described in Japanese Patent Application Publication No. 2005-099248 (especially compounds described in paragraphs

[0092] to

[0096] ), compounds described in paragraphs

[0013] to

[0059] of Japanese Patent No. 4385997, compounds described in paragraphs

[0018] to

[0044] of Japanese Patent No. 5034200, and compounds described in paragraphs

[0019] to

[0038] of Japanese Patent No. 4895088.

[0139] Surfactants can be used alone or in combination with two or more.

[0140] When the above-mentioned liquid crystal composition contains a surfactant, the content of the surfactant relative to the total solid content of the liquid crystal composition 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. When multiple surfactants are used together, it is preferable that the total amount of the multiple surface-modifying agents is within the above-mentioned range.

[0141] [Method for fabricating light-absorbing anisotropic films] The method for manufacturing the light-absorbing anisotropic film of the present invention is not particularly limited, and can be exemplified by a method comprising the following steps in sequence: a step of forming a coated film by coating the above-mentioned liquid crystal composition (hereinafter also referred to as "composition for forming a light-absorbing anisotropic film") (hereinafter also referred to as "coating film forming step"); and a step of orienting the liquid crystal components or dichroic substances contained in the coated film (hereinafter also referred to as "orientation step").

[0142] Furthermore, the liquid crystal component not only includes the aforementioned liquid crystal compound, but also includes a dichroic substance that has liquid crystal properties when the aforementioned dichroic substance has liquid crystal properties.

[0143] <Coating film formation process> The coating film forming process is a process of forming a coating film by coating a light-absorbing anisotropic film forming composition.

[0144] By using a light-absorbing anisotropic film forming composition containing the above-mentioned solvent, or by using a substance such as a liquid that is made into a melt by heating or the like, the light-absorbing anisotropic film forming composition can be easily coated.

[0145] As for the coating method of the composition for forming a light-absorbing anisotropic film, specifically, known methods such as roller coating, gravure printing, spin coating, wire rod coating, extrusion coating, direct gravure coating, reverse gravure coating, mold coating, spray coating, and inkjet coating can be cited.

[0146] In this invention, based on the premise of improved optical effects (e.g., viewing angle control), the coating amount of the dichroic substance in the coating film forming process is preferably 15 mg / m³. 2 More preferably, 50–1000 mg / m² 2 More preferably 200–800 mg / m³ 2 .

[0147] <Orientation Process> The alignment process is a process that orients the liquid crystal components contained in the coated film. As a result, an anisotropic light-absorbing film can be obtained.

[0148] The orientation process may include a drying process. This drying process removes components such as solvents from the coated film. The drying process can be performed by placing the coated film at room temperature for a specified time (e.g., natural drying), or by heating and / or air supply.

[0149] Here, the liquid crystal components contained in the light-absorbing anisotropic film forming composition are sometimes oriented through the above-described coating film forming process or drying process. For example, in the method of preparing the light-absorbing anisotropic film forming composition into a coating liquid containing a solvent, the solvent is removed from the coating film by drying the coating film to obtain a coating film with light absorption anisotropy (i.e., a light-absorbing anisotropic film).

[0150] If the drying process is carried out at a temperature above the transition temperature of the liquid crystal components contained in the coated film to the liquid crystal phase, the heating process described later may not be performed.

[0151] From the perspective of manufacturing applicability, the transition temperature of the liquid crystal component contained in the coating film to the liquid crystal phase is preferably 10 to 250°C, more preferably 25 to 190°C. If the transition temperature is 10°C or higher, there is no need for cooling treatment to lower the temperature to the temperature range of the liquid crystal phase, which is therefore preferable. Furthermore, if the transition temperature is 250°C or lower, even if it is set to an isotropic liquid state at a temperature higher than the temperature range of the temporary liquid crystal phase, high temperature is not required, which can reduce heat waste, substrate deformation and deterioration, etc., and is therefore preferable.

[0152] The alignment process preferably includes a heat treatment. This allows the liquid crystal components contained in the coated film to be aligned, thus enabling the heat-treated coated film to be preferably used as a light-absorbing anisotropic film.

[0153] From the perspective of manufacturing applicability, the heat treatment is preferably 10–250°C, more preferably 25–190°C. Furthermore, the heating time is preferably 1–300 seconds, more preferably 1–60 seconds.

[0154] The alignment process can include a cooling process performed after the heat treatment. The cooling process involves cooling the heated coating film to approximately room temperature (20–25°C). This helps to fix the alignment of the liquid crystal components contained in the coating film. There are no particular limitations on the cooling method; it can be implemented using known methods.

[0155] Through the above processes, an anisotropic light-absorbing film can be obtained.

[0156] Furthermore, in this method, drying treatment and heating treatment are cited as methods for aligning the liquid crystal components contained in the coating film, but it is not limited to these, and can be implemented by known alignment treatments.

[0157] <Other Processes> The method for forming a light-absorbing anisotropic film may also include a step of curing the light-absorbing anisotropic film after the above-mentioned orientation step (hereinafter also referred to as the "curing step").

[0158] For example, when the light-absorbing anisotropic film has crosslinking groups (polymeric groups), the curing process is carried out by heating and / or light irradiation (exposure). Among these, the curing process is preferably carried out by light irradiation.

[0159] The light source used for curing can be various light sources such as infrared, visible light, or ultraviolet light, but ultraviolet light is preferred. Furthermore, during curing, ultraviolet light can be irradiated while heating is being performed, or ultraviolet light can be irradiated through a filter that transmits only a specific wavelength.

[0160] When heating is performed simultaneously with exposure, the heating temperature during exposure depends on the transition temperature of the liquid crystal components contained in the liquid crystal film to the liquid crystal phase, but is preferably 25 to 140°C.

[0161] Furthermore, exposure can be performed under a nitrogen atmosphere. In the case of curing the liquid crystal film via free radical polymerization, to reduce polymerization hindrance caused by oxygen, exposure under a nitrogen atmosphere is preferred.

[0162] The thickness of the light-absorbing 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.

[0163] Here, regarding the thickness of the light-absorbing anisotropic film, a sample with an exposed cross-section was prepared by cutting with a slicer, and then observed and measured from the normal direction relative to the cross-section using a scanning electron microscope.

[0164] [Layered Body] The laminate of the present invention has the light-absorbing anisotropic film of the present invention as described above.

[0165] Furthermore, the laminate of the present invention may have at least one of a polarizer layer, an anti-reflection layer, and a phase difference layer.

[0166] [Polarizer layer] Regarding the polarizer layer, as long as it is a component that has the function of converting light into specific linearly polarized light, there are no particular restrictions, and conventionally known absorptive polarizers and reflective polarizers can be used.

[0167] As an absorption-type polarizer, iodine-based polarizers, dye-based polarizers utilizing dichroic dyes, and polyene-based polarizers can be used. Iodine-based polarizers and dye-based polarizers include coated polarizers and stretching polarizers, both of which can be used, but coated polarizers are preferred.

[0168] Furthermore, as a method for obtaining a polarizer by stretching and dyeing a laminated film in which a polyvinyl alcohol layer is formed on a substrate, examples include Japanese Patent No. 5048120, Japanese Patent No. 5143918, Japanese Patent No. 4691205, Japanese Patent No. 4751481, and Japanese Patent No. 4751486, and known technologies related to these polarizers can also be preferred.

[0169] Examples of coating-type polarizers include WO2018 / 124198, WO2018 / 186503, WO2019 / 132020, WO2019 / 132018, WO2019 / 189345, Japanese Patent Application Publication No. 2019-197168, Japanese Patent Application Publication No. 2019-194685, and Japanese Patent Application Publication No. 2019-139222. Known technologies related to these polarizers can also be preferentially utilized.

[0170] As a reflective polarizer, polarizers can be obtained by stacking thin films with different birefringence, wire grid polarizers, and polarizers obtained by combining cholesteric liquid crystal with a selective reflection region and a quarter-wave plate.

[0171] Among these, from the viewpoint of superior adhesion, a polarizer comprising a polyvinyl alcohol-based resin (a polymer containing -CH2-CHOH- as repeating units. In particular, at least one selected from the group consisting of polyvinyl alcohol and ethylene-vinyl alcohol copolymers) is preferred.

[0172] Furthermore, from the viewpoint of imparting crack resistance, the polarizer can have a depolarization section formed along the opposite end edges. Japanese Patent Application Publication No. 2014-240970 can be cited as an example of a depolarization section.

[0173] Furthermore, the polarizer may have non-polarizing portions arranged at predetermined intervals in the length and / or width directions. The non-polarizing portions are decolorized portions that are partially decolorized. The arrangement pattern of the non-polarizing portions can be appropriately set according to the purpose. For example, when the polarizer is cut (cut, punched, etc.) to a predetermined size for mounting on an image display device of a predetermined size, the non-polarizing portions are arranged at a position corresponding to the camera section of the image display device. Japanese Patent Application Publication No. 2016-27392 can be cited as an example of the arrangement pattern of the non-polarizing portions.

[0174] [Anti-reflective layer] There are no particular limitations on the anti-reflective layer; any known anti-reflective layer can be used.

[0175] As an anti-reflective layer, for example, the anti-reflective layer described in paragraphs 0108 to 0121 of International Publication No. 2016 / 047648, the above content of which is incorporated into this specification.

[0176] [Phase difference layer] There are no particular limitations on the phase difference layer; any known phase difference layer can be used.

[0177] Examples of phase retardation layers include stretched polycarbonate films, stretched norbornene polymer films, transparent films containing birefringent inorganic particles such as strontium carbonate that are oriented, thin films obtained by tilting the deposition of inorganic dielectrics on a support, and films in which liquid crystal compounds are uniaxially oriented and fixed in orientation.

[0178] Furthermore, the phase retardation layer is preferably the film described above that fixes the orientation of the liquid crystal compound by uniaxial orientation.

[0179] [Image display device] The image display device of the present invention is an image display device having the laminate of the present invention.

[0180] The display element used in the image display device of the present invention is not particularly limited. Examples include liquid crystal cells, organic electroluminescent (hereinafter referred to as "EL") display panels, inorganic EL display panels, and plasma display panels.

[0181] [Perspective switching device] The image display device of the present invention can be an image display device having the stacked body and electronically controlled viewing angle switching unit of the present invention, that is, an image display device (viewing angle switching device) capable of switching viewing angles.

[0182] By using the light-absorbing anisotropic film of the present invention, the light emission angle can be reduced.

[0183] Various types of image display devices with switchable viewing angles are known, but in order to generate light with a narrow emission angle, the light-absorbing anisotropic film or laminate of the present invention can be used.

[0184] For example, after generating light with a narrow emission angle using the light-absorbing anisotropic film or laminate of the present invention, as described in Japanese Patent Application Publication No. 9-105907, the narrow viewing angle / wide viewing angle can be switched by controlling whether the light is diffused by an element.

[0185] Alternatively, in a narrow-viewing-angle / wide-viewing-angle switching backlight system as described in Japanese Patent Application Publication No. 2017-098246, consisting of a reverse prism sheet, a first light guide plate that incident light onto the reverse prism sheet at a relatively large incident angle (light emitted from the reverse prism sheet has a narrow viewing angle), a filter element that absorbs light incident from an inclined direction and incident light with a narrow emission angle onto the reverse prism sheet at a relatively small incident angle, and a second light guide plate (light emitted from the reverse prism sheet has a narrow viewing angle), the light-absorbing anisotropic film or laminate of the present invention can be used as the filter element.

[0186] Furthermore, in a backlight system in which a first light guide plate, a filter that absorbs incident light from an inclined direction and emits light at a narrow angle, and a second light guide plate are sequentially stacked from the visual recognition side, and the light-emitting light is wide when light is emitted from the first light guide plate and narrow when light is emitted only from the second light guide plate, the light-absorbing anisotropic film or laminate of the present invention can also be used as the aforementioned filter.

[0187] Furthermore, a phase difference modulation element such as a liquid crystal cell can be disposed between the light-absorbing anisotropic film and the horizontally aligned polarizer of the present invention to switch between narrow and wide viewing angles. For example, if a liquid crystal cell in VA mode or ECB mode is used as the phase difference modulation unit, a narrow viewing angle is achieved when the liquid crystal in the liquid crystal cell is vertically aligned, and a wide viewing angle is achieved when the liquid crystal in the liquid crystal cell is tilted. The narrow / wide viewing angle can be controlled by whether or not a voltage is applied to the cell.

[0188] Furthermore, the use of IPS-mode liquid crystal cells as phase difference modulation units can also be considered. By making the orientation direction of the liquid crystal cell when no voltage is applied parallel or perpendicular to the absorption axis direction of the horizontal alignment polarizer, and by applying voltage to change the orientation direction of the liquid crystal cell, the viewing angle can be switched from a narrow viewing angle to a wide viewing angle.

[0189] Furthermore, TN-mode liquid crystal cells can also be considered as phase difference modulation units. Preferably, the unit is one that can switch the orientation twist angle to 0° and 90° or 0° and 270° by switching the voltage ON and OFF.

[0190] In addition, the image display device of the present invention can be configured to independently switch the viewing angles of multiple areas within the display screen.

[0191] [Optical Devices / Head-Mounted Displays] The light-absorbing anisotropic film of the present invention can be used in optical devices (head-mounted displays) with a light guide plate having diffraction elements disposed on the surface.

[0192] exist Figure 1A schematic diagram of an example of the head-mounted display of the present invention is shown in the figure.

[0193] Figure 1 The head-mounted display 80 shown is an example of AR glasses and includes a light guide plate 82, an incident diffraction element 90 and an exit diffraction element 92 disposed on one surface of the light guide plate 82, a filter 10, and an image display element 86. Furthermore, the light guide plate 82, the incident diffraction element 90 and the exit diffraction element 92, and the filter 10 constitute the laminate of the present invention.

[0194] like Figure 1 As shown, an incident diffraction element 90 is disposed on the surface (main surface) of one end of the light guide plate 82. Furthermore, an exit diffraction element 92 is disposed on the surface of the other end of the light guide plate 82.

[0195] The incident diffraction element 90 is positioned to correspond to the incident position of the image light I1 from the image display element 86 onto the light guide plate 82. Conversely, the exit diffraction element 92 is positioned to correspond to the exit position of the image light I1 from the light guide plate 82, i.e., the user's observation position of the image light I1. Furthermore, the incident diffraction element 90 and the exit diffraction element 92 are disposed on the same surface of the light guide plate 82.

[0196] Furthermore, the filter 10 is disposed opposite to the emission diffraction element 92 of the light guide plate 82 on the side of the light guide plate 82 opposite to the side where the emission diffraction element 92 is disposed.

[0197] like Figure 1 As shown, the filter 10 has the same shape as the emitted diffraction element 92.

[0198] Additionally, an intermediate diffraction element 94 may be disposed on the light guide plate 82 (see reference). Figure 2 ).

[0199] Furthermore, the placement of each diffraction element is not limited to the end of the light guide plate; various positions can be utilized depending on the shape of the light guide plate.

[0200] In this type of head-mounted display 80 (AR glasses), as indicated by the arrow, the image light I1 displayed by the image display element 86 is diffracted by the incident diffraction element 90 and incident into the light guide plate 82 at an angle of total internal reflection at the interface between the light guide plate 82 and the air.

[0201] The image light I1 incident on the light guide plate 82 is totally reflected at both surfaces of the light guide plate 82 and guided within the light guide plate 82, and then incident on the emission diffraction element 92.

[0202] The image light I1 incident on the emission diffraction element 92 is diffracted by the emission diffraction element 92 in a direction perpendicular to the surface of the emission diffraction element 92.

[0203] The image light I1 diffracted by the emitted diffraction element 92 is emitted to a user-based observation position located outside the light guide plate 82, so that it can be observed by the user.

[0204] Preferably, an air gap is provided between the filter 10 and the light guide plate 82. Without an air gap, when the image light I1 traveling within the light guide plate 82 is incident on the filter 10, it undergoes total internal reflection on the surface of the filter 10 opposite to the light guide plate 82 and attenuates due to absorption as it propagates again within the filter 10. By providing an air gap between the filter 10 and the light guide plate 82, the image light I1 is prevented from entering the filter from the light guide plate, thus solving the aforementioned problem.

[0205] And, as Figure 1 As shown, external light I0, which is incident on the head-mounted display 80 from the front direction, is incident on the light guide plate 82 through the background transmission filter 10 and is transmitted out through the diffraction element 92 to reach the user's viewing position. In the following description, external light incident on the head-mounted display 80 from the front direction is also referred to as front external light I0.

[0206] Thus, the head-mounted display 80 incident the image displayed by the image display element 86 onto one end of the light guide plate 82 and propagates it, and then emits it from the other end, thereby overlaying the virtual image onto the scene actually seen by the user.

[0207] Furthermore, the shape of the filter 10 is not limited to the same shape as the diffraction element; it can be a different shape, and its size can also be different. However, in order to filter incident external light from the tilted direction of the diffraction element, i.e., tilted external light I... s To effectively block light and suppress unnecessary shading of the background, i.e., the front external light I0, the diffraction element and filter are preferably identical in shape, including size.

[0208] As for the light guide plate 82, there are no particular limitations, and conventionally known light guide plates used in various AR glasses, backlight units of liquid crystal display devices, and image display devices can be used.

[0209] The image display element 86 is not limited and can utilize various known image display elements (displays) used in various image display devices such as AR glasses.

[0210] As an example of an image display element 86, examples include liquid crystal displays (including LCOS (Liquid Crystal On Silicon), organic electroluminescent displays, inorganic electroluminescent displays, DLP (Digital Light Processing), MEMS (Micro-Electro-Mechanical Systems) type displays, and micro LED (Light-Emitting Diode) displays.

[0211] In addition, the image display element 86 can display monochrome images, two-color images, or color images.

[0212] In the optical device of the present invention, a filter having a covering diffraction element and including the stack of the present invention is preferably a filter having a stack 14 and a polarizer 12 as shown in the example figure.

[0213] The optical device of the present invention, by having such a filter 10 (10m), exhibits high light transmittance in the front direction (front external light I0) when used in head-mounted displays such as AR glasses, resulting in excellent visual recognition of the background, and is able to suppress external light (oblique external light I0) incident from the top of the observer's head (slanted upward front of the top of the head). s The rainbow-like unevenness caused by external light incident from the top front of the observer's head is preferably suppressed. Moreover, the optical device according to the present invention is preferably able to suppress not only the rainbow-like unevenness caused by external light incident from the top front of the observer's head (oblique front of the top of the head), but also the rainbow-like unevenness caused by external light incident from the top front of the observer's head (oblique front of the top of the head).

[0214] In the optical device of the present invention, the angle between the absorption axis (orientation direction of the liquid crystal compound) of the laminate 14 constituting the 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 of the main surface of the laminate 14 and the main surface of the light guide plate 82.

[0215] On the other hand, the polarizer 12 constituting the filter 10 is a polarizer having an absorption axis within its main surface. That is, the polarizer has an absorption axis parallel to the main surface of the laminate 14 and the main surface of the light guide plate 82.

[0216] Furthermore, in the present invention, when the filter has a laminate 14 and a polarizer 12, from the viewpoint of improving light resistance, it is preferable to place the laminate 14 on the side of the light guide plate 82.

[0217] Example The present invention will now be described in further detail with reference to embodiments. The materials, amounts, proportions, processing contents, and processing steps shown in the following embodiments can be appropriately modified without departing from the spirit of the invention. Therefore, the scope of the present invention should not be limited by the embodiments shown below.

[0218] [Example 1] (1) Pseudo-support, The cellulose acylated membrane 1 (60 μm thick TAC substrate; FUJITACTG60UL FUJIFILM Corporation) used as a pseudo-support was saponified with an alkaline solution.

[0219] (2) Fabrication of the alignment film The following orientation film forming composition 1 was coated onto a cellulose acylated membrane 1. The support with the coated film was dried with warm air at 145°C for 120 seconds to form the orientation film 1. The thickness of the orientation film 1 was 0.5 μm.

[0220] ─────────────────────────────── Composition 1 for Orientation Film Formation ------------------------------------------------------------- • 10.0 parts by weight of the following polymer PA-1 • 0.83 parts by weight of the following acid-producing agent PAG-1 • 0.06 parts by weight of the following stabilizer DIPEA 100 parts by weight of butyl acetate 25 parts by weight of methyl ethyl ketone ------------------------------------------------------------- Polymer PA-1 [Chemical Formula 6] Acid-producing agent PAG-1 [Chemical Formula 7] stabilizer DIPEA [Chemical Formula 8] (3) Fabrication of light-absorbing anisotropic membranes Using a wire rod, the light-absorbing anisotropic membrane forming composition 1, consisting of the following components, is coated onto the obtained oriented TAC (triacetyl cellulose) membrane, and heated at 120°C for 60 seconds, then cooled to 35°C. Next, it is heated at 75°C for 60 seconds, and then cooled again to room temperature.

[0221] Then, under nitrogen purging conditions (oxygen concentration below 100 ppm), using an LED (light emitting diode) lamp (center wavelength 365 nm), at an illuminance of 200 mW / cm² from the normal direction of the film. 2 The light-absorbing anisotropic film 1 was fabricated on the alignment film 1 by irradiating it for 2 seconds under the specified irradiation conditions. The thickness of the light-absorbing anisotropic film 1 is 4.5 μm.

[0222] ------------------------------------------------------------- Composition 1 for forming light-absorbing anisotropic films ------------------------------------------------------------- • 0.91 parts by mass of the following dichroic substance D-1 • 0.22 parts by mass of the following dichroic substance D-2 • 1.49 parts by mass of the following dichroic substance D-3 • 8.15 parts by weight of the following polymeric liquid crystal compound P-1 • 1.85 parts by weight of the following low molecular weight liquid crystal compound L-1 • 0.20 parts by weight of the following IRGACUE OXE-2 (manufactured by BASF) • 0.16 parts by weight of the following vertical alignment agent E-1 • 0.16 parts by weight of the following vertical alignment agent E-2 • 0.007 parts by weight of the following surfactant F-1 78.17 parts by weight of cyclopentanone 8.69 parts by weight of benzyl alcohol ------------------------------------------------------------- Dichroic substance D-1 (maximum absorption wavelength: 410nm) [Chemical Formula 9] Dichroic substance D-2 (maximum absorption wavelength: 455nm) [Chemical Formula 10] Dichroic substance D-3 (maximum absorption wavelength: 612nm) [Chemical Formula 11] P-1, a high molecular weight liquid crystal compound (weight average molecular weight: 20,000). [Chemical Formula 12] 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] [Chemical Formula 13] Vertical Orientation Agent E-1 [Chemical Formula 14] Vertical Orientation Agent E-2 [Chemical Formula 15] Surfactant F-1 [In the following formula, the numbers represent the content (mass%) of each repeating unit relative to all repeating units. TMS represents trimethylsilyl.] (weight-average molecular weight: 28500) [Chemical Formula 16] (4) Fabrication of the protective layer The surface of the obtained light-absorbing anisotropic film 1 was subjected to corona treatment under the conditions of 4.0 m / min, 440 W, and 2.0 mm gap.

[0223] Next, a protective layer forming liquid 1 with the following composition is applied to the corona-treated light-absorbing anisotropic film 1 using a wire rod, thereby forming a coating film.

[0224] Next, the dummy support with the coating is dried with warm air at 60°C for 60 seconds, and then further dried with warm air at 100°C for 120 seconds, thereby forming the protective layer 1.

[0225] Then, under nitrogen purging conditions (oxygen concentration below 100 ppm), an LED lamp (center wavelength 365 nm) was used to illuminate the membrane at an illuminance of 200 mW / cm² from the normal direction. 2The film was irradiated for 2 seconds under the specified irradiation conditions, thereby forming a protective layer 1 on the light-absorbing anisotropic film 1, thus fabricating the light-absorbing anisotropic film 1 (layer structure: pseudo-support 1 / orientation film 1 / light-absorbing anisotropic film 1 / protective layer 1). The thickness of the protective layer 1 is 0.5 μm.

[0226] ---------------------------------------------------------- Protective coating liquid formulation 1 ---------------------------------------------------------- • 3.80 parts by weight of the following modified polyvinyl alcohol PVA-1 • IRGACURE 2959 (manufactured by BASF) 0.20 parts by weight • 0.08 parts by weight of the following pigment compound G-1 70 parts by weight of water ·Methanol 30 parts by weight ---------------------------------------------------------- Modified polyvinyl alcohol PVA-1 [where the numbers in the following formula represent the content (mass%) of each repeating unit relative to all repeating units.] (Degree of polymerization: 1700) [Chemical Formula 17] Pigment compound G-1 [Chemical Formula 18] [Example 2] The light-absorbing anisotropic film 2 was prepared by replacing the light-absorbing anisotropic film forming composition 1 with the light-absorbing anisotropic film forming composition 2 with the following composition. Otherwise, the light-absorbing anisotropic film 2 was prepared in the same manner as in Example 1 (layer structure: pseudo-support 1 / orientation film 1 / light-absorbing anisotropic film 2 / protective layer 1).

[0227] ------------------------------------------------------------- Composition 2 for forming light-absorbing anisotropic films ------------------------------------------------------------- • 0.91 parts by mass of the above dichroic substance D-1 • 0.22 parts by mass of the above dichroic substance D-2 • 1.49 parts by mass of the above dichroic substance D-3 • 8.15 parts by weight of the following polymeric liquid crystal compound P-2 • 1.85 parts by mass of the above-mentioned low molecular weight liquid crystal compound L-1 • IRGACUE OXE-2 (manufactured by BASF) 0.20 parts by weight • 0.16 parts by weight of the above-mentioned orientation agent E-1 • 0.16 parts by weight of the above-mentioned orientation agent E-2 • 0.007 parts by weight of the above surfactant F-1 78.17 parts by weight of cyclopentanone 8.69 parts by weight of benzyl alcohol ------------------------------------------------------------- P-2, a high molecular weight liquid crystal compound (weight average molecular weight: 21000). [Chemical Formula 19] [Example 3] The light-absorbing anisotropic film 3 was prepared by replacing the light-absorbing anisotropic film forming composition 1 with the light-absorbing anisotropic film forming composition 3 with the following composition. Otherwise, the light-absorbing anisotropic film 3 was prepared in the same manner as in Example 1 (layer structure: pseudo-support 1 / orientation film 1 / light-absorbing anisotropic film 3 / protective layer 1).

[0228] ------------------------------------------------------------- Composition 3 for forming light-absorbing anisotropic films ------------------------------------------------------------- • 0.91 parts by mass of the above dichroic substance D-1 • 0.22 parts by mass of the above dichroic substance D-2 • 1.49 parts by mass of the above dichroic substance D-3 • 8.15 parts by weight of the following polymeric liquid crystal compound P-3 • 1.85 parts by mass of the above-mentioned low molecular weight liquid crystal compound L-1 • IRGACUE OXE-2 (manufactured by BASF) 0.20 parts by weight • 0.16 parts by weight of the above-mentioned orientation agent E-1 • 0.16 parts by weight of the above-mentioned orientation agent E-2 • 0.007 parts by weight of the above surfactant F-1 78.17 parts by weight of cyclopentanone 8.69 parts by weight of benzyl alcohol ------------------------------------------------------------- P-3, a high molecular weight liquid crystal compound (weight average molecular weight: 19000). [Chemical Formula 20] [Comparative Example 1] An anisotropic light-absorbing film H1 was prepared by replacing the light-absorbing anisotropic film forming composition 1 with the light-absorbing anisotropic film forming composition H1 with the following composition. Otherwise, the light-absorbing anisotropic film H1 was prepared in the same manner as in Example 1 (layer structure: pseudo-support 1 / orientation film 1 / light-absorbing anisotropic film H1 / protective layer 1).

[0229] ------------------------------------------------------------- Composition H1 for forming light-absorbing anisotropic films ------------------------------------------------------------- • 0.91 parts by mass of the following dichroic substance D-4 • 0.22 parts by mass of the above dichroic substance D-2 • 1.49 parts by mass of the above dichroic substance D-3 • 8.15 parts by mass of the above-mentioned polymeric liquid crystal compound P-1 • 1.85 parts by mass of the above-mentioned low molecular weight liquid crystal compound L-1 • IRGACUE OXE-2 (manufactured by BASF) 0.20 parts by weight • 0.16 parts by weight of the above-mentioned orientation agent E-1 • 0.16 parts by weight of the above-mentioned orientation agent E-2 • 0.007 parts by weight of the above surfactant F-1 78.17 parts by weight of cyclopentanone 8.69 parts by weight of benzyl alcohol ------------------------------------------------------------- Dichroic substance D-4 (maximum absorption wavelength: 418nm) [Chemical Formula 21] [Comparative Example 2] A light-absorbing anisotropic film H2 was prepared by replacing the light-absorbing anisotropic film forming composition 1 with the light-absorbing anisotropic film forming composition H2 with the following composition. Otherwise, the light-absorbing anisotropic film H2 was prepared in the same manner as in Example 1 (layer structure: pseudo-support 1 / orientation film 1 / light-absorbing anisotropic film H2 / protective layer 1).

[0230] ------------------------------------------------------------- Composition H2 for forming light-absorbing anisotropic films ------------------------------------------------------------- • 0.63 parts by mass of the following dichroic substance D-5 • 0.17 parts by mass of the above dichroic substance D-2 • 1.13 parts by mass of the above dichroic substance D-3 • 8.18 parts by mass of the above-mentioned polymeric liquid crystal compound P-1 • IRGACUE OXE-2 (manufactured by BASF) 0.16 parts by weight • 0.13 parts by weight of the above-mentioned orientation agent E-1 • 0.13 parts by weight of the above-mentioned orientation agent E-2 • 0.004 parts by weight of the following surfactant F-2 · Cyclopentanone 85.01 parts by weight 4.47 parts by weight of benzyl alcohol ------------------------------------------------------------- Dichroic substance D-5 (maximum absorption wavelength: 415nm) [Chemical Formula 22] Surfactant F-2 [In the following formula, the numbers represent the content (mass%) of each repeating unit relative to all repeating units.] (Weight-average molecular weight: 16000) [Chemical Formula 23] [Comparative Example 3] A light-absorbing anisotropic film H3 was prepared by replacing the light-absorbing anisotropic film forming composition 1 with the light-absorbing anisotropic film forming composition H3 with the following composition. Otherwise, the light-absorbing anisotropic film H3 was prepared in the same manner as in Example 1 (layer structure: pseudo-support 1 / orientation film 1 / light-absorbing anisotropic film H3 / protective layer 1).

[0231] ------------------------------------------------------------- Composition H3 for forming light-absorbing anisotropic films ------------------------------------------------------------- • 0.91 parts by mass of the above dichroic substance D-5 • 0.22 parts by mass of the above dichroic substance D-2 • 1.49 parts by mass of the above dichroic substance D-3 • 8.15 parts by mass of the above-mentioned polymeric liquid crystal compound P-1 • 1.85 parts by mass of the above-mentioned low molecular weight liquid crystal compound L-1 • IRGACUE OXE-2 (manufactured by BASF) 0.20 parts by weight • 0.16 parts by weight of the above-mentioned orientation agent E-1 • 0.16 parts by weight of the above-mentioned orientation agent E-2 • 0.007 parts by weight of the above surfactant F-1 78.17 parts by weight of cyclopentanone 8.69 parts by weight of benzyl alcohol ------------------------------------------------------------- The transmittance central axis angle θ of the light-absorbing anisotropic films prepared in Examples 1-3 and Comparative Examples 1-3 was measured using the above method, and the results were all 0°.

[0232] [evaluate] (1) Physical property value An anisotropic absorber film was scraped from the obtained film, and DSC was performed using the method described above. The endothermic onset temperature of the endothermic peak originating from the dichroic material and the maximum endothermic peak temperature of the matrix were determined. The results are shown in Table 1 below. Furthermore, as mentioned above, in Figure 4 The figure shows the DSC curve of the anisotropic absorbance film prepared in Example 1. Figure 5 The figure shows the DSC curve of the anisotropic absorbance film prepared in Comparative Example 1. Figure 6 The figure shows the DSC curves of the matrix-only light-absorbing anisotropic films prepared in Example 1 and Comparative Example 1.

[0233] Furthermore, the ΔlogP values ​​of the dichroic substance and the matrix were calculated using the method described above. The results are shown in Table 1 below.

[0234] (2) Orientation The orientation degree of the obtained light-absorbing anisotropic film at wavelengths of 450 nm and 550 nm was calculated using the following method.

[0235] When measuring with AxoScan OPMF-1 (manufactured by Opto Science, Inc.), the angle relative to the normal direction of the light-absorbing anisotropic layer, i.e., the polar angle, was changed in 1° increments between -70° and 70°. At the same time, the Mueller matrix at wavelengths of 450 nm and 550 nm at each polar angle was measured, and the minimum transmittance (Tmin) was derived.

[0236] Next, after removing the influence of surface reflection, Tmin in the polar angle where Tmin becomes the highest is set as Tm(0), and Tmin in the direction of further increasing the polar angle by 40° from the highest polar angle of Tmin is set as Tm(40).

[0237] The absorbance (A) was calculated based on the obtained Tm(0) and Tm(40) using the following formula, and A(0) and A(40) were calculated.

[0238] A = -log(Tm) Here, Tm represents transmittance and A represents absorbance.

[0239] Based on the calculated A(0) and A(40), the orientation degree at wavelength 450 nm (S(450)) and the orientation degree at wavelength 550 nm (S(550)) as defined by the following formula are calculated respectively. The results are shown in Table 1 below. In addition, if S(450 nm) is 0.90 or above, it can be evaluated as a high orientation degree.

[0240] S=(4.6×A(40)-A(0)) / (4.6×A(40)+2×A(0)) (3) Haze value Regarding the light-absorbing anisotropic films prepared in Examples 1-3 and Comparative Examples 1-3, the haze values ​​were measured using a haze meter (NDH2000, manufactured by NIPPON DENSHOKU INDUSTRIES CO.,LTD.) at 25°C and 55% relative humidity. The results are shown in Table 1 below. Furthermore, regarding the haze value measurement, measurements were performed using each prepared light-absorbing anisotropic film at n=3, and the average value was taken as the haze value. The measurement was performed with light incident from the dummy support side. A haze value of 0.50% or less was considered low.

[0241] As shown in Table 1, if the endothermic onset temperature of the endothermic peak of the dichroic material observed in DSC is less than 105°C, the orientation degree becomes lower and the haze value becomes higher (Comparative Examples 1-3).

[0242] In contrast, it can be seen that if the endothermic onset temperature of the endothermic peak originating from dichroic substances observed in DSC is above 105°C, the orientation degree becomes higher and the haze value becomes lower (Examples 1-3).

[0243] In particular, as can be seen from the comparison of Examples 1 to 3, if the maximum endothermic peak temperature of the matrix is ​​above 108°, the haze value becomes lower.

[0244] Symbol Explanation 10-Filter, 12-Polarizer, 14-Laminator, 80-Head-mounted Display, 82-Light Guide Plate, 90-Incident Diffraction Element, 92-Outgoing Diffraction Element, 94-Intermediate Diffraction Element, I0-Front-facing External Light, I1-Image Light, I s - Slanted external light.

Claims

1. A light-absorbing anisotropic film comprising a dichroic substance and a matrix composed of all components other than the dichroic substance, wherein in the light-absorbing anisotropic film, Differential scanning calorimetry (DSC) revealed at least one endothermic peak originating from the dichroic substance, and all of these endothermic peaks had an endothermic onset temperature of 105 °C or higher. in, The endothermic onset temperature refers to the temperature at which 6% of the heat flow is displayed when the heat flow at the peak of the endothermic peak is set to 100% in a differential scanning calorimetry curve with the vertical axis set to heat flow and the horizontal axis set to temperature, and it is a temperature lower than the temperature at the peak of the endothermic peak.

2. The light-absorbing anisotropic film according to claim 1, wherein, At least one endothermic peak originating from the matrix was observed by differential scanning calorimetry, and the peak of the endothermic peak showing the maximum heat flux was observed to be above 108°C.

3. The light-absorbing anisotropic film according to claim 1 or 2, wherein, The absolute value of the difference between the logP value of the dichroic substance and the logP value of the matrix is ​​4.8 to 5.

8.

4. The light-absorbing anisotropic film according to claim 1 or 2, wherein, The angle θ between the transmittance central axis of the light-absorbing anisotropic film and the normal direction of the surface of the light-absorbing anisotropic film is greater than 0° and less than 45°.

5. The light-absorbing anisotropic film according to claim 1 or 2, wherein, The dichroic substance is a mixture containing at least a pigment compound having a maximum absorption wavelength in the range of wavelengths above 380 nm and below 455 nm, a pigment compound having a maximum absorption wavelength in the range of wavelengths above 455 nm and below 560 nm, and a pigment compound having a maximum absorption wavelength in the range of wavelengths above 560 nm and below 700 nm.

6. A laminate having the light-absorbing anisotropic film as described in claim 1 or 2.

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