Light-absorbing anisotropic film, viewing angle control system, and image display device

Abstract

To provide a light-absorbing anisotropic film capable of displaying a bright and clear image in an image display device from a desired direction and not viewing the image from other directions, a viewing angle control system using the light-absorbing anisotropic film, and an image display device using the viewing angle control system. A light-absorbing anisotropic film composed of a light-absorbing anisotropic layer containing a liquid crystal compound and an organic dichroic substance, and a first alignment layer adjacent to the light-absorbing anisotropic layer, the angle between the transmission central axis of the light-absorbing anisotropic layer and the normal line of the light-absorbing anisotropic layer being 5° or more and less than 45°, and the first alignment layer mixing and aligning a polymerizable liquid crystal compound, thereby solving the problem.

Description

Technical Field

[0001] The present invention relates to a light-absorbing anisotropic thin film for viewing angle control, a viewing angle control system using the light-absorbing anisotropic thin film, and an image display device using the viewing angle control system. Background Technology

[0002] When using in-vehicle displays such as car navigation systems, there are problems such as light shining upwards from the display screen onto the windshield, which can obstruct driving.

[0003] To address this problem, for example, Patent Document 1 provides a method for using a first polarizer having an in-plane absorption axis and a second polarizer (light absorption anisotropic layer) that orients the absorption axis of an organic dichroic material at 0° to 45° relative to the normal direction. Here, the first polarizer can be a polarizer used on the visual recognition side of a liquid crystal display device.

[0004] In this method, by transmitting only light from an image in a specific direction and blocking light transmission at other angles, the image can be viewed by an observer in the desired direction, but the image cannot be projected from a direction other than that, such as a windowpane.

[0005] Previous technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent No. 4902516 Summary of the Invention

[0008] The technical problem to be solved by the invention

[0009] In the aforementioned prior art, when manufacturing the light absorption anisotropic layer used in the viewing angle control device, a photo-alignment film using azobenzene pigments or the like is exposed to ultraviolet light from an obliquely upward position, generating anisotropy with a tilt angle on the surface of the photo-alignment film. A coating liquid for forming a light absorption anisotropic layer containing organic dichroic substances and liquid crystal compounds is then applied onto it and dried, thereby allowing the liquid crystal compounds and organic dichroic substances to be tilted and oriented for use.

[0010] However, in this method of generating anisotropy with a tilt angle on the surface of a photo-alignment film by ultraviolet exposure, the ultraviolet exposure device must be a high-output device capable of irradiating precisely parallel light. Furthermore, simultaneously, in order to ensure uniform tilt angle of the organic dichroic material and to eliminate irradiation from light outside the desired angle, measures to effectively suppress stray light and other large-scale reflected light in the exposure environment are required.

[0011] As a result, the cost burden associated with the exposure apparatus used to form the light-absorbing anisotropic layer becomes very high in this method. Furthermore, related to this, in conventional methods that apply an angle to the photo-aligned film for ultraviolet exposure, the deviation in the orientation direction of the light-absorbing anisotropic layer of the produced film increases, leading to a decrease in the quality of the film.

[0012] Therefore, the objective of this invention is to provide a light-absorbing anisotropic thin film with low cost associated with the exposure apparatus used in the orientation control of the light-absorbing anisotropic layer and uniform orientation of the organic dichroic material in the light-absorbing anisotropic layer, a viewing angle control system using the light-absorbing anisotropic thin film, and an image display device using the viewing angle control system.

[0013] means for solving technical problems

[0014] The inventors have discovered that the above-mentioned problem can be achieved through the following configuration.

[0015] (1) A light-absorbing anisotropic thin film, which has the following characteristics:

[0016] Anisotropic light-absorbing layer; and

[0017] The first orientation layer is adjacent to the light absorption anisotropic layer.

[0018] The light-absorbing anisotropic layer contains liquid crystal compounds and organic dichroic substances.

[0019] The angle between the transmittance central axis of the light-absorbing anisotropic layer and the normal to the light-absorbing anisotropic layer is greater than 5° and less than 45°.

[0020] The first orientation layer is a layer formed by fixing a polymeric liquid crystal compound with a mixed orientation in which the orientation direction in the thickness direction continuously changes from one surface side to another.

[0021] (2) According to the light-absorbing anisotropic thin film described in (1), wherein,

[0022] The first orientation layer is a layer formed from a composition having polymerizable polymer liquid crystals.

[0023] (3) The light-absorbing anisotropic thin film according to (1) or (2), wherein,

[0024] The angle between the orientation axis of the polymeric liquid crystal compound at the interface of the first orientation layer and the normal of the first orientation layer is 2° to 50°.

[0025] (4) The light-absorbing anisotropic thin film according to any one of (1) to (3), wherein,

[0026] The ratio of the organic dichroic material to the total solid content of the light-absorbing anisotropic layer is more than 5% by mass.

[0027] (5) The light-absorbing anisotropic thin film according to any one of (1) to (4), wherein,

[0028] The liquid crystal compound of the light-absorbing anisotropic layer includes a polymeric liquid crystal compound, and the polymeric liquid crystal compound includes a liquid crystal compound displaying a smectic phase.

[0029] (6) The light-absorbing anisotropic thin film according to any one of (1) to (5), having a second orientation layer adjacent to the side of the first orientation layer opposite to the side of the light-absorbing anisotropic layer and formed of polyvinyl alcohol or polyimide.

[0030] (7) A viewing angle control system having a polarizer and a light-absorbing anisotropic thin film as described in any one of (1) to (6).

[0031] (8) An image display device having the viewing angle control system described in (7) disposed on at least one main surface of a display panel.

[0032] Invention Effects

[0033] According to the present invention, a low-cost light-absorbing anisotropic thin film with uniform orientation of the light-absorbing anisotropic layer can be provided. Attached Figure Description

[0034] Figure 1 This is a schematic cross-sectional view illustrating an example of an embodiment of the liquid crystal display device of the present invention.

[0035] Figure 2 This is a schematic cross-sectional view illustrating an example of an embodiment of the light-absorbing anisotropic thin film of the present invention.

[0036] Figure 3 This is a conceptual cross-sectional view showing the orientation of the liquid crystal molecules and dichroic material inside the light-absorbing anisotropic thin film of the present invention.

[0037] Figure 4 This is a diagram showing the relationship between the direction of the transmittance center axis of the light-absorbing anisotropic layer and the position of the absorption axis of the polarizer in the embodiment.

[0038] Figure 5 This is a diagram conceptually representing a cutting method for measuring the orientation angle of a slice used in the first orientation layer.

[0039] Figure 6 This is a diagram that conceptually represents the method for measuring the orientation angle of the first orientation layer. Detailed Implementation

[0040] The present invention will now be described in detail.

[0041] 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.

[0042] In addition, the numerical range indicated by “~” in this specification refers to the range including the lower limit and upper limit values ​​of the values ​​recorded before and after “~”.

[0043] Furthermore, in this specification, parallel and orthogonal do not refer to parallel and orthogonal in the strict sense, but rather to a range of ±5° from parallel or orthogonal.

[0044] Furthermore, in this specification, "(meth)acrylate" is used to mean "any one or both of acrylate and methacrylate".

[0045] Furthermore, in this specification, liquid crystal compositions and liquid crystal compounds include the concept of no longer exhibiting liquid crystal properties through curing or the like.

[0046] <Image display device>

[0047] In addition to liquid crystal display devices, the image display device of the present invention can also use organic electroluminescent display devices and other display devices. As an example, a liquid crystal display device will be used for explanation.

[0048] like Figure 1 As shown, the liquid crystal display device 100 of the present invention is a liquid crystal display device having at least, sequentially from the visual recognition side, a light-absorbing anisotropic thin film 101, a visual recognition side polarizer 102, a liquid crystal cell 103, a back light side polarizer 104, and a back light 105.

[0049] The light-absorbing anisotropic thin film 101 is the light-absorbing anisotropic thin film of the present invention and has a light-absorbing anisotropic layer and a first orientation layer.

[0050] The light-absorbing anisotropic thin film 101 can utilize various structures as long as it has the light-absorbing anisotropic layer and the first orientation layer described later.

[0051] The light-absorbing anisotropic thin film 101 of the present invention is not limited to this structure. As an example, such as Figure 2 As shown conceptually, it has a blocking layer 1, a light-absorbing anisotropic layer 2, a first orientation layer 3, a second orientation layer 4, and a TAC film 5 in sequence.

[0052] TAC membrane 5 is the support for the light-absorbing anisotropic layer 101. Additionally, TAC membrane is short for triacetylcellulose membrane.

[0053] In this invention, the direction of the absorption axis of the polarizer is sometimes referred to as longitudinal or transverse. However, in the case of a liquid crystal display device in normal use, the direction of the side of the liquid crystal display device closer to the vertical direction is referred to as longitudinal, and the direction of the side of the liquid crystal display device closer to the horizontal direction is referred to as transverse.

[0054] [Light Absorption Anisotropic Layer]

[0055] The light-absorbing anisotropic layer is mainly composed of organic dichroic substances and liquid crystal compounds. Other components may include polymerization initiators, leveling agents, and orientation control agents.

[0056] Various compounds, including low-molecular-weight and high-molecular-weight liquid crystal compounds, can be used as the liquid crystal compound. However, in order to achieve a good orientation state of the organic dichroic material in the light-absorbing anisotropic layer, it is preferable to contain at least a portion of a high-molecular-weight liquid crystal compound. Furthermore, by using a high-molecular-weight liquid crystal compound, the difference in tilt angle between the liquid crystal compound at the air-side interface and the support-side interface of the light-absorbing anisotropic layer can be suppressed to a smaller extent, which is also preferable in terms of obtaining good viewing angle characteristics.

[0057] In order to control the light transmission direction of the light-absorbing anisotropic layer, it is preferable to orient the organic dichroic material that has absorption in the visible region in the desired direction. For example, a light-absorbing anisotropic layer in which at least one organic dichroic material is tilted relative to the normal direction of the film can be described.

[0058] As a light-absorbing anisotropic layer in which an organic dichroic material is tilted and oriented, it is even more preferable to use a host-guest liquid crystal cell manufacturing technique and to align the organic dichroic material as the guest by aligning the orientation of the liquid crystal compound that becomes the host.

[0059] Furthermore, as is widely known, a normal is a direction orthogonal to the main surface of a sheet-like object (thin film, layer, membrane, plate), for example, ... Figure 2 The stacking directions of the layers in the anisotropic light-absorbing thin film are shown. Furthermore, it is well known that the main surface is the largest surface of the sheet, typically the two surfaces along the thickness direction.

[0060] In the light-absorbing anisotropic thin film of the present invention, when controlling the orientation direction of the organic dichroic material, i.e., the liquid crystal compound, in the light-absorbing anisotropic layer, a first orientation layer adjacent to the light-absorbing anisotropic layer is utilized.

[0061] As will be described in detail later, the first orientation layer is a layer formed by fixing a polymeric liquid crystal compound with a mixed orientation in which the orientation direction in the thickness direction continuously changes from one surface side to another.

[0062] Previously, the orientation direction of organic dichroic pigments (liquid crystal compounds) in a light-absorbing anisotropic layer was controlled using a photoalignment layer containing photoalignment materials such as azobenzene pigments and polyethylene cinnamate. That is, ultraviolet light was irradiated onto the photoalignment layer containing the photoalignment material from an angled direction relative to the normal direction of the photoalignment layer, thereby generating anisotropy relative to the normal direction of the photoalignment layer.

[0063] A light-absorbing anisotropic layer is formed on a light-alignment layer that imparts tilted anisotropy using a composition containing a liquid crystal compound and an organic dichroic substance. The liquid crystal compound, which forms the main component, is tilted and oriented according to the anisotropy of the light-alignment layer. Following the orientation of the liquid crystal compound, the organic dichroic substance in the light-absorbing anisotropic layer is also oriented.

[0064] However, in this method of using photo-aligned layers, if it is desired to fully align and control the organic dichroic pigments in the anisotropic light absorption layer, the illuminance reduction caused by ultraviolet radiation from the tilted direction is several tens to hundreds of times greater than that required for conventional photocuring ultraviolet exposure, which requires thousands of mJ / cm². 2 Exposure.

[0065] Furthermore, in this orientation method, the orientation direction is determined based on the incident angle of the ultraviolet light. Therefore, to obtain a uniform orientation direction, a light source with high output and capable of illuminating highly parallel light is required. In addition, to obtain a uniform orientation direction, measures are needed to suppress irregular reflections of stray light within the optical system and exposure apparatus.

[0066] Therefore, the orientation method using dichroic pigments with photo-alignment layers places a greater burden on the processing and equipment.

[0067] Furthermore, methods are also being considered, such as using rubbing treatment on polyimide alignment layers with special functional groups that are easy to impart a large orientation angle, in order to replace photo-alignment layers.

[0068] However, in these methods, the orientation angle of the organic dichroic pigments (organic compounds) in the light-absorbing anisotropic layer of the present invention is insufficient when controlling the angle between the central axis of the transmittance of the light-absorbing anisotropic layer and the normal of the light-absorbing anisotropic layer to be 5° or more and less than 45°. Furthermore, in these methods, the orientation direction (pitch direction) cannot be freely changed as needed.

[0069] Therefore, in this invention, instead of a light alignment layer, a liquid crystal layer made of a mixed alignment liquid crystal compound is used as the first alignment layer in order to control the alignment direction of the light absorption anisotropic layer, thereby solving the above-mentioned problem.

[0070] Furthermore, there is no particular limitation on the method for determining the orientation angle of the first orientation layer. An example is a method of providing a second orientation layer adjacent to the side of the first orientation layer opposite to the light-absorbing anisotropic layer and having an in-plane orientation restraining force. The second orientation layer is preferably a rub-treated polyvinyl alcohol layer or a rub-treated polyimide layer.

[0071] Regarding techniques for orienting organic dichroic materials in a desired direction, reference can be made to techniques for fabricating polarizers using organic dichroic materials and techniques for fabricating host-guest liquid crystal cells. As described above, in the light-absorbing anisotropic thin film of the present invention, the light-absorbing anisotropic layer is a layer containing a liquid crystal compound and an organic dichroic material.

[0072] As an example, such as Figure 3 The light-absorbing anisotropic layer 2, conceptually shown, uses a liquid crystal compound 11 as the host material, tilted and oriented in a desired direction. Along the liquid crystal compound, dichroic substances D-1 (reference numeral 13), D-2 (reference numeral 14), and D-3 (reference numeral 15), serving as objects, are oriented. Furthermore, dichroic substances D-1, D-2, and D-3 are, for example, organic dichroic substances with different absorption peak wavelengths.

[0073] Regarding the orientation of such dichroic materials, the techniques used, for example, in the manufacturing methods of dichroic polarizing elements described in Japanese Patent Application Publication No. 11-305036 and Japanese Patent Application Publication No. 2002-90526, and in the manufacturing methods of host-guest type liquid crystal display devices described in Japanese Patent Application Publication No. 2002-99388 and Japanese Patent Application Publication No. 2016-27387, can also be used in the fabrication of the light-absorbing anisotropic layer used in the light-absorbing anisotropic thin film of the present invention.

[0074] For example, by using guest-host type liquid crystal cell technology, the molecules of organic dichroic substances can be oriented as described above, depending on the orientation of the host liquid crystal.

[0075] Specifically, by mixing an organic dichroic substance as the object and a rod-shaped liquid crystal compound as the host liquid crystal, the host liquid crystal is oriented and the molecules of the organic dichroic substance are oriented along with the orientation of its liquid crystal molecules, thereby fixing its orientation state, and thus the light absorption anisotropic layer used in this invention can be produced.

[0076] To prevent variations in the light absorption characteristics of the anisotropic light-absorbing layer used in this invention due to environmental conditions, it is preferable to fix the orientation of the organic dichroic material through the formation of chemical bonds. For example, the orientation can be fixed by polymerizing the host liquid crystal, the organic dichroic material, and polymerizable components as desired.

[0077] Furthermore, a host-guest type liquid crystal cell having a liquid crystal layer comprising at least an organic dichroic substance and a host liquid crystal on a pair of substrates can be used itself as the light absorption anisotropic layer used in this invention. The orientation of the host liquid crystal (and the orientation of the accompanying organic dichroic substance molecules) can be controlled by an alignment film formed on the inner surface of the substrate. As long as no external stimulation such as an electric field is applied, its orientation state can be maintained, and the light absorption characteristics of the light absorption anisotropic layer used in this invention can be maintained constant.

[0078] Furthermore, by permeating the organic dichroic material into the polymer film and orienting the organic dichroic material along the orientation of the polymer molecules in the polymer film, a polymer film that can be used as the light absorption anisotropic layer of the light absorption anisotropic thin film of the present invention can be produced.

[0079] Specifically, this method involves coating a solution of an organic dichroic substance onto the surface of a polymer film and allowing it to permeate into the film. The orientation of the organic dichroic substance can be adjusted based on the orientation of the polymer chains in the polymer film, their properties (chemical and physical properties of the polymer chains or their functional groups), and the coating method. Details of this method are described in Japanese Patent Application Publication No. 2002-90526.

[0080] As an anisotropic light absorption layer, the transmission central axis of the polymer film can be detected in the same way as described later.

[0081] In the light-absorbing anisotropic thin film of the present invention, the angle between the central axis of the transmittance of the light-absorbing anisotropic layer and the normal of the light-absorbing anisotropic layer is 5° or more and less than 45°.

[0082] When the angle between the central axis of transmittance and the normal of the light absorption anisotropic layer is less than 5°, adverse conditions such as narrowing the design freedom of the in-vehicle configuration including the image display device will occur.

[0083] Furthermore, even if the angle between the transmittance center axis and the normal of the light-absorbing anisotropic layer is set to 45° or more, it is difficult to observe the image from such a shallow angle. Moreover, in the frontal direction where the brightness of the emitted light from the image display device is high and the optical path length through the optical anisotropic layer is reduced, the light-blocking effect becomes insufficient. In other words, if the angle between the transmittance center axis and the normal of the light-absorbing anisotropic layer is 45° or more, it is not optimal from the viewpoint of the viewpoint control system, resulting in poor visibility from the set visual recognition direction, insufficient light blocking other than the set visual recognition direction, and increased reflected glare on the center window glass in applications such as automotive.

[0084] The angle between the central axis of transmittance and the normal of the light absorption anisotropic layer is preferably 5° to 30°, more preferably 5° to 15°.

[0085] In addition, the transmittance center axis refers to the direction in which transmittance is highest when the slope angle (polar angle) and slope direction (azimuth angle) of the normal direction relative to the main surface of the light-absorbing anisotropic layer are changed to measure transmittance.

[0086] Although also shown in the embodiments below, regarding the transmittance central axis of the light-absorbing anisotropic layer, for example using an AxoScan OPMF-1 (manufactured by Opto Science, Inc.), the direction of the azimuth angle of the tilt of the transmittance central axis is first detected. In this azimuth angle direction, the polar angle is varied, and the Mueller matrix is ​​measured to derive the transmittance. The direction of the highest transmittance (polar angle) is set as the direction of the transmittance central axis of the light-absorbing anisotropic layer. This polar angle is the angle between the transmittance central axis in the light-absorbing anisotropic layer and the normal direction of the light-absorbing anisotropic layer.

[0087] In addition, the transmittance central axis (polar angle) of the light absorption anisotropic layer was measured at 15 randomly selected locations on the light absorption anisotropic layer, and the average of the polar angles was set as the transmittance central axis in the light absorption anisotropic layer.

[0088] Furthermore, in this invention, unless otherwise specified, these optical measurements are performed using light with a wavelength of 550 nm.

[0089] In the light absorption anisotropic layer used in this invention, the transmittance (below 550 nm) tilted 30° from the transmittance central axis is preferably 60% or less, more preferably 50% or less, and even more preferably 45% or less.

[0090] In the light-absorbing anisotropic layer used in this invention, the transmittance along the central axis is preferably 65% ​​or more, more preferably 75% or more, and even more preferably 85% or more. This improves the illuminance at the viewing angle center of the image display device and enhances visibility.

[0091] Furthermore, in terms of enabling the hue of the front direction to be set to neutral, the orientation degree of the light absorption anisotropic layer at 420nm preferably satisfies 0.93 or higher.

[0092] Tone control in anisotropic light-absorbing thin films containing dichroic substances is typically achieved by adjusting the amount of dichroic substance added. However, it is known that simply adjusting the amount of dichroic substance cannot neutralize the tone in both the front and tilted directions. The reason for this inability to neutralize the tone in both directions is the low orientation at 420 nm. By increasing the orientation at 420 nm, the tone in both directions can be neutralized.

[0093] Furthermore, in the light absorption anisotropic thin film of the present invention, the light absorption anisotropic layer can be stacked with multiple light anisotropic absorption layers at different centers of the transmission axis or stacked with phase difference layers to satisfy the transmittance tilted 30° from the center axis of transmittance and the transmittance of the center axis of transmittance.

[0094] By stacking multiple anisotropic absorption layers at different centers of the transmission axis, the width of the region with high transmittance can be adjusted. Furthermore, in the case of stacked retardation layers, the transmission / blocking performance can be controlled by adjusting the phase difference value and the optical axis direction. Positive A-plate, negative A-plate, positive C-plate, negative C-plate, B-plate, and O-plate can be used as retardation layers.

[0095] From the viewpoint of making the viewing angle control system thinner, the thickness of the retardation layer is preferably thinner without compromising optical properties, mechanical properties and manufacturing applicability. Specifically, it is preferably 1 to 150 μm, more preferably 1 to 70 μm, and even more preferably 1 to 30 μm.

[0096] [First Orientation Layer]

[0097] In the light-absorbing anisotropic thin film of the present invention, a first alignment layer is provided adjacent to the light-absorbing anisotropic layer and having a liquid crystal compound with mixed orientation.

[0098] Specifically, the first alignment layer is a layer formed by fixing a polymeric liquid crystal compound with a mixed orientation in which the alignment direction in the thickness direction continuously changes from one surface side to another. Figure 2 and Figure 3In the example shown, the first alignment layer 3 is a liquid crystal layer with mixed alignment in which the orientation direction of the liquid crystal molecules 11 continuously changes from the TAC film 3 (support) side to the barrier layer 1 (air side).

[0099] In this invention, the orientation direction of the liquid crystal compound in the first alignment layer is substantially as follows: Figure 3 As shown, the orientation direction of the liquid crystal molecules 11 changes continuously from the side opposite to the light-absorbing anisotropic layer towards the light-absorbing anisotropic layer side, so that the in-plane direction (horizontal orientation) becomes the normal direction (thickness direction, vertical orientation).

[0100] The orientation of the liquid crystal compound basically follows the orientation of the liquid crystal compound present in the bottom layer (formation surface).

[0101] As a function of the first alignment layer, the alignment angle (tilt angle) of the liquid crystal compound in the interface (air side interface) of the first alignment layer that becomes the light-absorbing anisotropic layer side is used to control the orientation angle (tilt angle) and orientation direction (azimuth direction) of the liquid crystal compound at the interface between the light-absorbing anisotropic layer and other liquid crystal layers disposed thereon and the first alignment layer.

[0102] There are no restrictions on the liquid crystal compound used in the first alignment layer; various known liquid crystal compounds can be used. Furthermore, it can be a rod-shaped liquid crystal compound or a disk-shaped liquid crystal compound.

[0103] Here, the first alignment layer and the light-absorbing anisotropic layer and other liquid crystal layers disposed thereon are preferably formed using the same type of liquid crystal compound or liquid crystal compounds with similar chemical structures, and more preferably using the same liquid crystal compound. By adopting this structure, the interaction between the first alignment layer and the light-absorbing anisotropic layer and other liquid crystal layers thereon is enhanced, and the alignment angle and alignment direction of the liquid crystal compounds in the light-absorbing anisotropic layer, etc., can be controlled with higher precision.

[0104] The liquid crystal compound of the first alignment layer can be formed using various liquid crystal compounds, including low-molecular-weight liquid crystal compounds and high-molecular-weight liquid crystal compounds. However, in order to obtain a uniform alignment state, it is preferable to use a high-molecular-weight liquid crystal compound to form the first alignment layer.

[0105] Furthermore, the liquid crystal compound in the first alignment layer can be either a high-molecular-weight liquid crystal or a low-molecular-weight liquid crystal, but is preferably a polymeric liquid crystal compound. By coating a coating solution containing the polymeric liquid crystal compound forming the first alignment layer, and then curing the first alignment layer before coating a coating solution forming the light-absorbing anisotropic layer, the first alignment layer is cured. This minimizes interference with the alignment of the liquid crystal compound in the first alignment layer caused by organic solvents or the like in the coating solution forming the light-absorbing anisotropic layer when the coating solution is applied to the first alignment layer. As a result, higher quality light-absorbing anisotropic thin films can be produced.

[0106] That is, the first orientation layer is preferably formed of a composition having polymerizable liquid crystal.

[0107] There is no limit to the thickness of the first orientation layer. The thickness can be appropriately set to exhibit sufficient orientation based on the material in which the first orientation layer is formed.

[0108] In the light-absorbing anisotropic layer, the thickness of the first orientation layer is preferably 0.1 to 5.0 μm in terms of obtaining a good orientation state. The thickness of the first orientation layer is more preferably 0.1 to 3.5 μm, and even more preferably 0.1 to 2.0 μm.

[0109] In the first alignment layer, the angle between the alignment axis (optical axis) of the liquid crystal compound at the interface on the light-absorbing anisotropic layer side and the normal of the first alignment layer is preferably 2° to 50°. That is, in the first alignment layer, the alignment angle of the liquid crystal compound at the interface on the light-absorbing anisotropic layer side relative to the normal is preferably 2° to 50°.

[0110] In the first alignment layer, it is preferable to set the alignment angle of the liquid crystal compound relative to the normal to 2° or more, so as to perform asymmetrical viewing angle control in the left-right or up-down directions.

[0111] Furthermore, even if the alignment angle of the liquid crystal compound relative to the normal is set to more than 50°, it is difficult to observe the image from such a shallow angle, and the light-blocking effect becomes insufficient in the front direction where the brightness of the emitted light from the image display device is high and the optical path length through the optical anisotropy layer is reduced. That is, in the first alignment layer, from the viewpoint of the viewpoint control direction of the viewpoint control system, by setting the alignment angle of the liquid crystal compound relative to the normal to 50° or less, sufficient visibility from the set visual recognition direction and light blocking from other than the set visual recognition direction are obtained, which is preferable in terms of reducing reflected glare on the center window glass in applications such as automotive.

[0112] In the first alignment layer, the alignment angle of the liquid crystal compound relative to the normal in the interface side of the light-absorbing anisotropic layer side is more preferably 3° to 45°, and even more preferably 5° to 35°.

[0113] As an example, the orientation angle of the liquid crystal compound relative to the normal at the interface on the light-absorbing anisotropic layer side in the first alignment layer is measured below.

[0114] First, such as Figure 5 Conceptually, after forming the first orientation layer on the support, the laminate is cut into 2μm sections parallel to the thickness direction (normal direction) to obtain sample slices 43. For example, a microtome can be used for this cutting.

[0115] Next, a polarizing microscope is used, such as... Figure 6 Conceptually, the polarizer and analyzer are positioned in the orthogonal Nicol, the azimuth angle of the slice 43 is moved and the azimuth angle of extinction on the air interface side of the first alignment layer, i.e. the interface of the light absorption anisotropy layer side, is observed. Then, a sensitive color plate (λ plate) is inserted, the azimuth angle is moved and the color change near the air interface is observed, the direction of the slow axis in the slice is adjusted, and the alignment angle of the liquid crystal compound at the air side interface is determined.

[0116] Similarly, for the support side of the first orientation layer, i.e. the second orientation layer side and the middle part of the first orientation layer, the azimuth angle of extinction is also adjusted, and then a sensitive color plate (λ plate) is inserted. The azimuth angle is moved and the color change is observed. This determines the direction of the slow axis in the slice, thereby confirming that the first orientation layer as a whole is a mixed orientation.

[0117] [Second Orientation Layer]

[0118] Preferably, the light-absorbing anisotropic thin film of the present invention has a second alignment layer on the side of the first alignment layer opposite to the light-absorbing anisotropic layer. Preferably, Figure 2 and Figure 3 The light-absorbing anisotropic thin film shown has a second orientation layer 4 on the surface of the TAC film 5, which serves as a support, a first orientation layer 3 on the surface of the second orientation layer 4, and a light-absorbing anisotropic layer on the surface of the first orientation layer 3.

[0119] The second alignment layer is an alignment layer with an in-plane orientation (azimuth direction) constraint force, and its orientation is the in-plane orientation of the liquid crystal compound in the first alignment layer. By having the second alignment layer, the in-plane orientation of the liquid crystal compound in the first alignment layer can be controlled more accurately. As a result, in the light absorption anisotropy layer, the in-plane orientation of the liquid crystal compound can be controlled more accurately.

[0120] As the second alignment layer, various known alignment layers (alignment films) can be used as long as the liquid crystal compound can be aligned in an in-plane direction. For example, a resin film composed of polyvinyl alcohol, polyimide, and polyfunctional (meth)acrylate compounds, etc., that has undergone rubbing treatment can be exemplified. Among these, rubbing-treated polyvinyl alcohol films and rubbing-treated polyimide films are preferably examples of the second alignment layer.

[0121] Furthermore, as a second orientation layer, it is also possible to utilize ultraviolet light or other linearly polarized light that is irradiated from the normal direction of the orientation layer, and to construct a photoorientation layer composed of photoorientation materials such as polyethylene cinnamate and azobenzene compounds.

[0122] [Liquid Crystal Compounds]

[0123] As described above, in the light-absorbing anisotropic thin film of the present invention, the light-absorbing anisotropic layer contains a liquid crystal compound and an organic dichroic substance. Furthermore, the first alignment layer is formed by mixing an alignment polymerizable liquid crystal compound.

[0124] In this invention, the liquid crystal compound can be either rod-shaped (rod-shaped liquid crystal compound) or disk-shaped (disk-shaped liquid crystal compound), but rod-shaped liquid crystal compound is preferred from the perspective of easy control of the orientation direction of the dichroic material.

[0125] The preferred type of rod-shaped liquid crystal compound is a liquid crystal compound that does not exhibit dichroism in the visible region.

[0126] As a rod-shaped liquid crystal compound, either a low-molecular-weight liquid crystal compound or a high-molecular-weight liquid crystal compound can be used. Here, "low-molecular-weight liquid crystal compound" refers to a liquid crystal compound that does not have repeating units in its chemical structure. And, "high-molecular-weight liquid crystal compound" refers to a liquid crystal compound that has repeating units in its chemical structure.

[0127] Examples of low-molecular-weight liquid crystal compounds include those described in Japanese Patent Application Publication No. 2013-228706.

[0128] Examples of polymeric liquid crystal compounds include, for instance, the thermotropic liquid crystal polymer described in Japanese Patent Application Publication No. 2011-237513. Furthermore, the polymeric liquid crystal compound may have crosslinking groups (e.g., acryloyl and methacryloyl groups) at its ends.

[0129] Rod-shaped liquid crystal compounds can be used alone or in combination of two or more.

[0130] From the perspective of further improving the effects of the present invention, the rod-shaped liquid crystal compound preferably contains a high molecular weight liquid crystal compound, and more preferably contains both a high molecular weight liquid crystal compound and a low molecular weight liquid crystal compound.

[0131] The rod-shaped liquid crystal compound preferably contains a liquid crystal compound or a polymer thereof represented by formula (LC). The liquid crystal compound or polymer thereof represented by formula (LC) is a compound exhibiting liquid crystal properties. Liquid crystal properties can be nematic phase, smectic phase, or both. If the liquid crystal property exhibited by the liquid crystal compound is a smectic liquid crystal phase, it is preferable to be able to fabricate a light absorption anisotropic layer with higher orientation order.

[0132] As a smectic phase, it can be a higher-order smectic phase. The higher-order smectic phases referred to here are smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic I phase, smectic J phase, smectic K phase and smectic L phase, among which, smectic B phase, smectic F phase and smectic I phase are preferred.

[0133] If the smectic liquid crystal phase displayed by the liquid crystal compound is one of these higher-order smectic liquid crystal phases, it is preferable to be able to fabricate a light absorption anisotropic layer with a higher degree of orientation order. Furthermore, such a light absorption anisotropic layer fabricated from a higher-order smectic liquid crystal phase with a high degree of orientation order is a layer in which Bragg peaks originating from higher-order structures called hexagonal phases and crystalline phases are obtained in X-ray diffraction measurements. These Bragg peaks are peaks originating from the planar periodic structure of molecular orientation. According to the liquid crystal composition of the present invention, it is possible to obtain a periodic interval of... Anisotropic light absorption layer.

[0134] [Chemical Formula 1]

[0135] Q1-S1-MG-S2-Q2 (LC)

[0136] In formula (LC), Q1 and Q2 independently represent hydrogen atoms, halogen atoms, straight-chain, branched, or cyclic alkyl groups with 1 to 20 carbon atoms, alkoxy groups with 1 to 20 carbon atoms, alkenyl groups with 1 to 20 carbon atoms, alkynyl groups with 1 to 20 carbon atoms, aryl groups with 1 to 20 carbon atoms, heterocyclic groups (also called heterocyclic groups), cyano, hydroxyl, nitro, carboxyl, aryloxy, silyloxy, heterocyclic, acyloxy, carbamoyloxy, alkoxycarbonyloxy, aryloxycarbonyloxy, amino (including aniline), ammonium, amide, aminocarbonylamino, alkoxycarbonylamino, aryloxycarbonylamino, aminosulfonylamino, alkyl or arylsulfonylamino, mercapto, alkylthio, arylthio, heterocyclic thio, aminosulfonyl, sulfonyl, alkyl or arylsulfinyl, alkyl or arylsulfonyl Acyl, aryloxycarbonyl, alkoxycarbonyl, carbamoyl, aryl or heterocyclic azo, imide, phosphin, oxyphosphinyl, oxyphosphinyloxy, oxyphosphinylamino, phosphonyl, silyl, hydrazine, urea, borate (-B(OH)2), phosphate (-OPO(OH)2), sulfate (-OSO3H) or a crosslinking group represented by the following formulas (P-1) to (P-30), wherein at least one of Q1 and Q2 is preferably a crosslinking group represented by the following formula.

[0137] [Chemical Formula 2]

[0138]

[0139] In equations (P-1) to (P-30), R P This refers to hydrogen atoms, halogen atoms, straight-chain, branched, or cyclic alkylene groups with 1 to 10 carbon atoms, haloalkyl groups with 1 to 20 carbon atoms, alkoxy groups with 1 to 20 carbon atoms, alkenyl groups with 1 to 20 carbon atoms, alkynyl groups with 1 to 20 carbon atoms, aryl groups with 1 to 20 carbon atoms, and heterocyclic groups (also known as heterocyclic groups). (group), cyano, hydroxy, nitro, carboxyl, aryloxy, siloxy, heterocyclic, acyloxy, carbamoyloxy, alkoxycarbonyloxy, aryloxycarbonyloxy, amino (including aniline), ammonium, acylamino, aminocarbonylamino, alkoxycarbonylamino, aryloxycarbonylamino, aminosulfonylamino, alkyl or arylsulfonylamino, mercapto, alkylthio, arylthio, heterocyclic thio, aminosulfonyl, sulfonyl, alkyl or arylsulfinyl, alkyl or arylsulfonyl, acyl, aryloxycarbonyl, alkoxycarbonyl, carbamoyl, aryl or heterocyclic azo, imide, phosphinyl, oxophosphinyl, oxophosphinyloxy, oxophosphinylamino, phosphonyl, silyl, hydrazine, urea, borate (-B(OH)2), phosphate (-OPO(OH)2) or sulfate (-OSO3H), multiple R P They can be the same or different.

[0140] Preferred crosslinking groups include free radical polymerizable groups and cationic polymerizable groups. For free radical polymerizable groups, preferred groups are vinyl groups represented by formula (P-1), butadiene groups represented by formula (P-2), (meth)acrylic acid groups represented by formula (P-4), (meth)acrylamide groups represented by formula (P-5), vinyl acetate groups represented by formula (P-6), fumarate groups represented by formula (P-7), styrene groups represented by formula (P-8), vinylpyrrolidone groups represented by formula (P-9), maleic anhydride groups represented by formula (P-11), or maleimide groups represented by formula (P-12). For cationic polymerizable groups, preferred groups are vinyl ether groups represented by formula (P-18), epoxy groups represented by formula (P-19), or oxobutyl groups represented by formula (P-20).

[0141] In equation (LC), S1 and S2 independently represent divalent spacer bases. Preferred embodiments of S1 and S2 can be exemplified by structures identical to SPW in equation (W1) above, so their description is omitted.

[0142] In formula (LC), MG represents the mesocrystalline group described later. The mesocrystalline group represented by MG refers to the group that represents the main framework of liquid crystal molecules that contribute to the formation of liquid crystals. Liquid crystal molecules exhibit liquid crystal properties, exhibiting an intermediate state (intermediate phase) between the crystalline state and the isotropic liquid state. There are no particular limitations regarding the mesocrystalline group; for example, one can refer to the description in "Flussige Kristalle in Tabernen II" (VEB Deutsche Verlag fur Grundstoff Industrie, Leipzig, 1984), especially pages 7-16, and the description in "Liquid Crystal Handbook Editorial Committee, Liquid Crystal Handbook" (Maruzen, 2000), especially Chapter 3.

[0143] The mesocrystalline group represented by MG preferably contains 2 to 10 cyclic structures, more preferably 3 to 7.

[0144] Specific examples of cyclic structures include aromatic hydrocarbon groups, heterocyclic groups, and alicyclic groups.

[0145] From the viewpoints of liquid crystal properties, liquid crystal phase transition temperature adjustment, raw material availability and synthetic suitability, as well as the viewpoint of superior effects of the present invention, groups represented by the following formula (MG-A) or the following formula (MG-B) are preferred as the mesocrystalline group represented by MG, and groups represented by formula (MG-B) are more preferred.

[0146] [Chemical Formula 3]

[0147]

[0148] In formula (MG-A), A1 is a divalent group selected from the group consisting of aromatic hydrocarbon groups, heterocyclic groups, and alicyclic groups. These groups can be substituted by substituents such as W.

[0149] The divalent group represented by A1 is preferably a 4- to 15-membered ring. Furthermore, the divalent group represented by A1 can be a monocyclic ring or a fused ring.

[0150] * indicates the bonding position with S1 or S2.

[0151] Examples of divalent aromatic hydrocarbon groups represented by A1 include phenylene, naphthylene, fluorene-diyl, anthracene-diyl, and tetraphenyl-diyl. From the perspective of the diversity of mesocrystalline framework design and the availability of raw materials, phenylene and naphthylene are preferred.

[0152] The divalent heterocyclic group represented by A1 can be either aromatic or non-aromatic, but from the viewpoint of further improving the degree of orientation, a divalent aromatic heterocyclic group is preferred.

[0153] Examples of atoms other than carbon that constitute a divalent aromatic heterocyclic group include nitrogen, sulfur, and oxygen atoms. When an aromatic heterocyclic group has multiple atoms constituting the ring (excluding carbon), these atoms can be the same or different.

[0154] Specific examples of divalent aromatic heterocyclic groups include, for example, pyridinyl (pyridin-diyl), pyridazin-diyl, imidazole-diyl, thiophene (thiophene-diyl), quinoline (quinoline-diyl), isoquinoline (isoquinoline-diyl), oxazol-diyl, thiazole-diyl, oxadiazole-diyl, benzothiazole-diyl, benzothiadiazole-diyl, phthalimide-diyl, thienothiazole-diyl, thiazonothiazole-diyl, thienothiazole-diyl, and thienooxazol-diyl, as well as the structures (II-1) to (II-4) below.

[0155] [Chemical Formula 4]

[0156]

[0157] In equations (II-1) to (II-4), D1 represents -S-, -O-, or NR. 11 -, R 11 Y1 represents an alkyl group with 1 to 6 carbon atoms, Y2 represents an aromatic hydrocarbon group with 6 to 12 carbon atoms or an aromatic heterocyclic group with 3 to 12 carbon atoms, and Z1, Z2, and Z3 independently represent an aliphatic hydrocarbon group with 1 to 20 carbon atoms, an alicyclic hydrocarbon group with 3 to 20 carbon atoms, an aromatic hydrocarbon group with 6 to 20 carbon atoms in monovalent form, a halogen atom, a cyano group, a nitro group, and -NR, respectively.12 R 13 or -SR 12 Z1 and Z2 can bond with each other to form an aromatic ring or an aromatic heterocycle, R 12 and R 13 Each of the following groups independently represents an alkyl group having 1 to 6 carbon atoms, and J1 and J2 independently represent groups selected from -O-, -NR-, etc. 21 -(R 21 The group represents a hydrogen atom or a substituent. E represents a nonmetallic atom of group 14-16 that can bond with a hydrogen atom or a substituent. Jx represents an organic group having 2-30 carbon atoms, selected from the group consisting of aromatic hydrocarbon rings and aromatic heterocycles. Jy represents a hydrogen atom, an alkyl group having 1-6 carbon atoms that can have substituents, or an organic group having 2-30 carbon atoms, selected from the group consisting of aromatic hydrocarbon rings and aromatic heterocycles. The aromatic rings of Jx and Jy can have substituents, and Jx and Jy can bond to form a ring. D2 represents a hydrogen atom or an alkyl group having 1-6 carbon atoms that can have substituents.

[0158] In formula (II-2), when Y1 is an aromatic hydrocarbon group with 6 to 12 carbon atoms, it can be either a monocyclic or polycyclic ring. When Y1 is an aromatic heterocyclic group with 3 to 12 carbon atoms, it can be either a monocyclic or polycyclic ring.

[0159] In equation (II-2), J1 and J2 represent -NR 21 - In the case of R 21 The substituents, for example, can be described in paragraphs

[0035] to

[0045] of Japanese Patent Application Publication No. 2008-107767, which are incorporated herein by reference.

[0160] In formula (II-2), when E is a nonmetallic atom of group 14 to 16 that can be bonded by a substituent, it is preferable to have =O, =S, =NR', or =C(R')R'. R' represents a substituent, and as a substituent, reference can be made to paragraphs

[0035] to

[0045] of Japanese Patent Application Publication No. 2008-107767, preferably -NZ. A1 Z A2 (Z A1 and Z A2 Each can be represented independently by a hydrogen atom, alkyl group, or aryl group.

[0161] Specific examples of the divalent alicyclic group represented by A1 include cyclopentylene and cyclohexylene, etc., in which the carbon atom can be replaced by -O-, -Si(CH3)2-, -N(Z)- (Z represents hydrogen, alkyl, cycloalkyl, aryl, cyano or halogen atom with 1 to 4 carbon atoms, -C(O)-, -S-, -C(S)-, -S(O)- and -SO2-, or groups formed by combining two or more of these groups.

[0162] In formula (MG-A), a1 represents an integer from 2 to 10. Multiple A1s can be the same or different.

[0163] In formula (MG-B), A2 and A3 are each independently a divalent group selected from the group consisting of aromatic hydrocarbon groups, heterocyclic groups, and alicyclic groups. Specific examples and preferred embodiments of A2 and A3 are the same as those of A1 in formula (MG-A), therefore their description is omitted.

[0164] In formula (MG-B), a2 represents an integer from 1 to 10. Multiple A2s can be the same or different, and multiple LA1s can be the same or different. Considering the superior effect of the present invention, a2 is more preferably 2 or more.

[0165] In equation (MG-B), LA1 is a single bond or a divalent linker. However, when a2 is 1, LA1 is a divalent linker, and when a2 is 2 or more, at least one of the plurality of LA1s is a divalent linker.

[0166] In equation (MG-B), the divalent linker represented by LA1 is the same as that of LW, so its description is omitted.

[0167] As a specific example of MG, the following structures can be cited, in which the hydrogen atoms on the aromatic hydrocarbon group, heterocyclic group and alicyclic group can be replaced by the substituent W mentioned above.

[0168] [Chemical Formula 5]

[0169]

[0170] [Chemical Formula 6]

[0171]

[0172] [Chemical Formula 7]

[0173]

[0174] <Low molecular weight liquid crystal compounds>

[0175] When the liquid crystal compound represented by formula (LC) is a low molecular weight liquid crystal compound, the preferred cyclic structure of the mesocrystalline group MG includes cyclohexylene, cyclopentylene, phenylene, naphthylene, fluorene-diyl, pyridine-diyl, pyridazine-diyl, thiophene-diyl, oxazole-diyl, thiazole-diyl, thiophene-thiophene-diyl, etc., and the number of cyclic structures is preferably 2 to 10, and more preferably 3 to 7.

[0176] Preferred types of substituents W for mesocrystalline structures include halogen atoms, haloalkyl groups, cyano groups, hydroxyl groups, nitro groups, carboxyl groups, alkoxy groups with 1 to 10 carbon atoms, alkyl carbonyl groups with 1 to 10 carbon atoms, alkoxy carbonyl groups with 1 to 10 carbon atoms, alkyl carbonyloxy groups with 1 to 10 carbon atoms, amino groups, alkylamino groups with 1 to 10 carbon atoms, alkylamino carbonyl groups, groups in which LW in the above formula (W1) is a single bond and SPW is a divalent spacer group and Q is a crosslinking group represented by (P1) to (P30) above. As crosslinking groups, vinyl, butadiene, (meth)acryloyl, (meth)acrylamido, vinyl acetate, fumarate, styrene, vinylpyrrolidone, maleic anhydride, maleimide, vinyl ether, epoxy, and oxetane.

[0177] The preferred configurations of the divalent spacer bases S1 and S2 are the same as those for SPW described above, so their description is omitted.

[0178] When using a low-molecular-weight liquid crystal compound that exhibits smectic properties, the number of carbon atoms in the spacer group (which is the number of atoms when the carbon is replaced by "SP-C") is preferably 6 or more, and more preferably 8 or more.

[0179] When the liquid crystal compound represented by formula (LC) is a low-molecular-weight liquid crystal compound, multiple low-molecular-weight liquid crystal compounds can be used together, preferably 2 to 6 types, and more preferably 2 to 4 types. By using low-molecular-weight liquid crystal compounds together, the solubility can be improved and the phase transition temperature of the liquid crystal composition can be adjusted.

[0180] Specific examples of low-molecular-weight liquid crystal compounds include compounds represented by the formulas (LC-1) to (LC-77), but low-molecular-weight liquid crystal compounds are not limited to these.

[0181] [Chemical Formula 8]

[0182]

[0183] [Chemical Formula 9]

[0184]

[0185] <Polymer Liquid Crystal Compounds>

[0186] The polymeric liquid crystal compound is preferably a homopolymer or copolymer containing repeating units described later, and can be any polymer such as random polymer, end-capped polymer, grafted polymer, star polymer, etc.

[0187] (Repeated unit (1))

[0188] The polymeric liquid crystal compound preferably contains a repeating unit represented by formula (1) (hereinafter also referred to as "repeating unit (1)").

[0189] [Chemical Formula 10]

[0190]

[0191] In formula (1), PC1 represents the main chain of the repeating unit, L1 represents the single bond or divalent linker, SP1 represents the spacer, MG1 represents the mesocrystalline group MG in the above formula (LC), and T1 represents the terminal group.

[0192] As the main chain of the repeating unit represented by PC1, examples include groups represented by formulas (P1-A) to (P1-D), among which, from the viewpoint of the diversity of monomers that can be used as raw materials and ease of handling, groups represented by the following formula (P1-A) are preferred.

[0193] [Chemical Formula 11]

[0194]

[0195] In equations (P1-A) to (P1-D), "*" indicates the bonding position with L1 in equation (1). In equations (P1-A) to (P1-D), R... 11 R 12 R 13 R 14 Each of the above-mentioned alkyl groups independently represents a hydrogen atom, a halogen atom, a cyano group, or an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. The alkyl group can be a straight-chain or branched alkyl group, or an alkyl group having a cyclic structure (cycloalkyl). Furthermore, the alkyl group preferably has 1 to 5 carbon atoms.

[0196] The group represented by formula (P1-A) is preferably a unit of a partial structure of poly(meth)acrylate obtained by polymerization of (meth)acrylate.

[0197] The group represented by formula (P1-B) is preferably an ethylene glycol unit formed by ring-opening polymerization of the epoxy group of a compound having an epoxy group.

[0198] The group represented by formula (P1-C) is preferably a propylene glycol unit formed by ring-opening polymerization of an oxetane compound having an oxetane.

[0199] The group represented by formula (P1-D) is preferably a siloxane unit of a polysiloxane obtained by polycondensation of a compound having at least one of alkoxysilyl and silanol groups. Here, as a compound having at least one of alkoxysilyl and silanol groups, an example is a compound having the formula SiR 14 (OR 15 Compounds containing a group represented by )2-. In the formula, R 14 The meaning of R in equation (P1-D) 14 The meanings are the same, multiple R 15 Alkyl groups, which can be independently represented by 1 to 10 hydrogen or carbon atoms respectively.

[0200] The divalent linker represented by L1 is the same divalent linker as LW in the above formula (W1). As a preferred embodiment, -C(O)O-, -OC(O)-, -O-, -S-, and -C(O)NR can be cited. 16 -、-NR 16 C(O)-, -S(O)2- and -NR 16 R 17 - etc. In the formula, R 16 and R 17 Each of the following groups independently represents a hydrogen atom and an alkyl group having 1 to 6 carbon atoms, which may have substituents (e.g., substituent W mentioned above). In a specific example of a divalent linker, the linker on the left is bonded to PC1, and the linker on the right is bonded to SP1.

[0201] When PC1 is a group represented by formula (P1-A), L1 is preferably -C(O)O- or C(O)NR. 16 - indicates a functional group.

[0202] When PC1 is a group represented by formulas (P1-B) to (P1-D), L1 is preferably a single bond.

[0203] The spacer group represented by SP1 is the same group as S1 and S2 in the above formula (LC). From the viewpoint of orientation, it is preferable to include a group with at least one structure selected from the group consisting of ethylene oxide, propylene oxide, polysiloxane, and fluorinated alkylene structures, or a straight-chain or branched alkylene with 2 to 20 carbon atoms. However, the alkylene may include -O-, -S-, -O-CO-, -CO-O-, -O-CO-O-, -O-CNR- (R represents an alkyl group with 1 to 10 carbon atoms), or -S(O)2-.

[0204] Considering reasons such as ease of liquid crystal properties and availability of raw materials, the spacer group represented by SP1 is more preferably a group containing at least one structure selected from the group consisting of ethylene oxide structure, propylene oxide structure, polysiloxane structure and fluorinated alkylene structure.

[0205] Here, the oxyethylene structure represented by SP1 is preferably composed of *-(CH2-CH2O). n1 -* indicates a group. In the formula, n1 represents an integer from 1 to 20, and * indicates the bonding position with L1 or MG1. For the sake of better performance of the present invention, n1 is preferably an integer from 2 to 10, more preferably an integer from 2 to 6, and most preferably 2 to 4.

[0206] Furthermore, the oxypropylene structure represented by SP1 is preferably *-(CH(CH3)-CH2O) n2 -* indicates a group. In the formula, n2 represents an integer from 1 to 3, and * indicates the bonding position with L1 or MG1.

[0207] Furthermore, the polysiloxane structure represented by SP1 is preferably composed of *-(Si(CH3)2-O). n3 -* indicates a group. In the formula, n3 represents an integer from 6 to 10, and * indicates the bonding position with L1 or MG1.

[0208] Furthermore, the fluorinated alkylene structure represented by SP1 is preferably composed of *-(CF2-CF2). n4 -* indicates a group. In the formula, n4 represents an integer from 6 to 10, and * indicates the bonding position with L1 or MG1.

[0209] Examples of terminal groups represented by T1 include hydrogen atoms, halogen atoms, cyano groups, nitro groups, hydroxyl groups, -SH groups, carboxyl groups, borate groups, -SO3H groups, -PO3H2 groups, and -NR groups. 11 R 12 (R 11 and R 12 Each group can independently represent a hydrogen atom or a substituted or unsubstituted alkyl, cycloalkyl, or aryl group with 1 to 10 carbon atoms, an alkyl group with 1 to 10 carbon atoms, an alkoxy group with 1 to 10 carbon atoms, an alkylthio group with 1 to 10 carbon atoms, an alkoxycarbonyloxy group with 1 to 10 carbon atoms, an acyloxy group with 1 to 10 carbon atoms, an amide group with 1 to 10 carbon atoms, an alkoxycarbonyl group with 1 to 10 carbon atoms, an alkoxycarbonylamino group with 1 to 10 carbon atoms, a sulfonylamino group with 1 to 10 carbon atoms, an aminosulfonyl group with 1 to 10 carbon atoms, a carbamoyl group with 1 to 10 carbon atoms, a sulfinyl group with 1 to 10 carbon atoms, a ureido group with 1 to 10 carbon atoms, or a group containing a crosslinking group.

[0210] Examples of groups containing crosslinking groups include -L-CL. L represents a single bond or a linking group. Specific examples of linking groups are the same as LW and SPW described above. CL represents a crosslinking group, and examples include groups represented by Q1 or Q2 described above, preferably groups represented by formulas (P1) to (P30) described above. Furthermore, T1 can also be a group composed of two or more of these groups.

[0211] For the sake of superior effects of the present invention, T1 is preferably an alkoxy group having 1 to 10 carbon atoms, more preferably an alkoxy group having 1 to 5 carbon atoms, and even more preferably a methoxy group. These terminal groups can be further replaced by these groups or polymerizable groups described in Japanese Patent Application Publication No. 2010-244038.

[0212] For the sake of superior performance of the present invention, the number of atoms in the main chain of T1 is preferably 1 to 20, more preferably 1 to 15, even more preferably 1 to 10, and particularly preferably 1 to 7. When the number of atoms in the main chain of T1 is 20 or less, the orientation degree of the light-absorbing anisotropic layer is further improved. Here, "main chain" in T1 refers to the longest molecular chain bonded to M1, and hydrogen atoms are not included in the number of atoms in the main chain of T1. For example, when T1 is n-butyl, the number of atoms in the main chain is 4, and when T1 is sec-butyl, the number of atoms in the main chain is 3.

[0213] The content of repeating unit (1) is preferably 40 to 100% by mass, more preferably 50 to 95% by mass, relative to the total repeating units (100% by mass) of the polymer liquid crystal compound. If the content of repeating unit (1) is 40% by mass or more, a light absorption anisotropy layer with good orientation can be obtained. Furthermore, if the content of repeating unit (1) is 100% by mass or less, a light absorption anisotropy layer with good orientation can be obtained.

[0214] The polymer liquid crystal compound may contain a single repeating unit (1) or two or more repeating units (1). In the case of containing two or more repeating units (1), the content of the repeating unit (1) refers to the total content of the repeating units (1).

[0215] (logP value)

[0216] In equation (1), the difference between the logP values ​​(hereinafter also referred to as "logP1") of PC1, L1 and SP1 and the logP value (hereinafter also referred to as "logP2") of MG1 (|logP1-logP2|) is preferably 4 or more, and from the viewpoint of further improving the orientation degree of the light absorption anisotropy layer, it is preferably 4.25 or more, and more preferably 4.5 or more.

[0217] Furthermore, from the viewpoint of adjusting the liquid crystal phase transition temperature and the suitability for synthesis, the upper limit of the above difference is preferably 15 or less, more preferably 12 or less, and even more preferably 10 or less.

[0218] 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 logP value is the value calculated by inputting the structural formula of the compound into HSPiP (Ver. 4.1.07).

[0219] As mentioned above, logP1 refers to the logP values ​​of PC1, L1, and SP1. The "logP values ​​of PC1, L1, and SP1" refers to the logP value of the structure in which PC1, L1, and SP1 are integrated, and is not the sum of the individual logP values ​​of PC1, L1, and SP1. Specifically, logP1 is calculated by inputting the series of structural formulas of PC1 to SP1 in equation (1) into the software.

[0220] However, when calculating logP1, in the series of structural formulas PC1 to SP1, the part concerning the group represented by PC1 can use the structure of the group represented by PC1 itself (e.g., the above formulas (P1-A) to (P1-D) etc.), or the structure of the group that may become PC1 after the monomer used to obtain the repeating unit represented by formula (1) is used.

[0221] Here, specific examples of the latter (which may become the group of PC1) are as follows. In the case where PC1 is obtained by the polymerization of (meth)acrylate, it is formed by CH2=C(R 1 )- represents the group (R) 1 (This represents a hydrogen atom or a methyl group.) Furthermore, when PC1 is obtained through the polymerization of ethylene glycol, it is ethylene glycol; when PC1 is obtained through the polymerization of propylene glycol, it is propylene glycol. Also, when PC1 is obtained through the polycondensation of silanols, it is silanol (from the formula Si(R...). 2 Compounds represented by )3(OH). Multiple R 2 Each R can independently represent a hydrogen atom or an alkyl group. However, multiple Rs... 2 At least one of them represents an alkyl group.

[0222] When the difference between logP1 and the above-mentioned logP2 is 4 or more, it can be lower than logP2 or higher than logP2.

[0223] Here, the logP value of a typical mesocrystalline group (logP2 mentioned above) tends to be in the range of 4 to 6. In this case, when logP1 is lower than logP2, the value of logP1 is preferably 1 or less, more preferably 0 or less. On the other hand, when logP1 is higher than logP2, the value of logP1 is preferably 8 or more, more preferably 9 or more.

[0224] When PC1 in formula (1) is obtained by polymerization of (meth)acrylate and logP1 is lower than logP2, the logP value of SP1 in formula (1) is preferably 0.7 or less, more preferably 0.5 or less. On the other hand, when PC1 in formula (1) is obtained by polymerization of (meth)acrylate and logP1 is higher than logP2, the logP value of SP1 in formula (1) is preferably 3.7 or more, more preferably 4.2 or more.

[0225] Furthermore, examples of structures with a logP value of 1 or less include the oxyethylene structure and the oxypropylene structure. Examples of structures with a logP value of 6 or more include the polysiloxane structure and the fluorinated alkylene structure.

[0226] (Repeated units (21) and (22))

[0227] From the viewpoint of improving the degree of orientation, the polymer liquid crystal compound preferably contains repeating units with electron-donating and / or electron-withdrawing properties at its ends. More specifically, it is more preferable to contain repeating units (21) having mesocrystalline groups and electron-withdrawing groups with σp values ​​greater than 0 at their ends, and repeating units (22) having mesocrystalline groups and groups with σp values ​​less than 0 at their ends. Thus, when the polymer liquid crystal compound contains repeating units (21) and repeating units (22), the degree of orientation of the light-absorbing anisotropic layer formed therefrom is improved compared to the case where only one of the repeating units (21) or repeating units (22) is contained. Although the details of the reasoning are not clear, it can be roughly inferred as follows.

[0228] That is, it is speculated that through the interaction between molecules by the opposite dipole moments generated in the repeating units (21) and (22), the interaction of the mesocrystalline groups in the short axis direction becomes stronger, the orientation of the liquid crystal becomes more uniform, and as a result, the degree of order of the liquid crystal is considered to be higher. Thus, it is speculated that the orientation of the dichroic material also becomes better, and therefore the degree of orientation of the formed light absorption anisotropic layer is higher.

[0229] In addition, the repeating units (21) and (22) mentioned above can also be repeating units represented by the above formula (1).

[0230] The repeating unit (21) has a mesocrystalline group and an electron-withdrawing group with a σp value greater than 0 at the end of the mesocrystalline group.

[0231] The electron-withdrawing groups mentioned above are those located at the end of the mesocrystalline group and have a σp value greater than 0. Examples of electron-withdrawing groups (groups with a σp value greater than 0) include the group represented by EWG in formula (LCP-21) described later, and specific examples are similar.

[0232] The σp value of the aforementioned electron-withdrawing groups is greater than 0. From the perspective of achieving a higher degree of orientation in the light-absorbing anisotropic layer, a value of 0.3 or higher is preferred, and 0.4 or higher is more preferred. From the perspective of excellent orientation uniformity, the upper limit of the σp value of the aforementioned electron-withdrawing groups is preferably 1.2 or less, and more preferably 1.0 or less.

[0233] The σp value refers to the Hammett substituent constant σp (also simply called "σp value"), which numerically represents the effect of the substituent at the acid dissociation equilibrium constant of benzoic acid. It is a parameter indicating the strength of the electron-withdrawing and electron-donating properties of the substituent. The Hammett substituent constant σp value in this specification refers to the substituent constant σ when the substituent is located at the para position of benzoic acid.

[0234] The Hammett substituent constant σp values ​​for each group in this specification are those described in the literature "Hansch et al., Chemical Reviews, 1991, Vol. 91, No. 2, 165-195". Additionally, for groups for which the Hammett substituent constant σp value is not shown in the aforementioned literature, the Hammett substituent constant σp value can be calculated using the software "ACD / ChemSketch (ACD / Labs 8.00 Release Product Version: 8.08)" based on the difference between the pKa of benzoic acid and the pKa of a benzoic acid derivative with a substituent at the para position.

[0235] The repeating unit (21) is not particularly limited as long as it has a mesocrystalline group in the side chain and an electron-withdrawing group with a σp value greater than 0 at the end of the mesocrystalline group. However, from the viewpoint that the orientation degree of the light-absorbing anisotropic layer becomes higher, the repeating unit represented by the following formula (LCP-21) is preferred.

[0236] [Chemical Formula 12]

[0237]

[0238] In formula (LCP-21), PC21 represents the main chain of repeating units, more specifically, it represents the same structure as PC1 in formula (1) above. L21 represents a single bond or a divalent linker, more specifically, it represents the same structure as L1 in formula (1) above. SP21A and SP21B represent single bonds or spacer groups, respectively. The specific example of the spacer group represents the same structure as SP1 in formula (1) above. MG21 represents a mesocrystalline structure, more specifically, it represents the mesocrystalline group MG in formula (LC) above. EWG represents an electron-withdrawing group with a σp value greater than 0.

[0239] The spacer groups represented by SP21A and SP21B represent the same groups as those in formulas S1 and S2 above, and preferably include groups with at least one structure selected from the group consisting of ethylene oxide, propylene oxide, polysiloxane, and fluorinated alkylene structures, or straight-chain or branched alkylene groups having 2 to 20 carbon atoms. However, the aforementioned alkylene groups may include -O-, -O-CO-, -CO-O-, or O-CO-O-.

[0240] For reasons such as ease of liquid crystal properties and availability of raw materials, the spacer group represented by SP1 preferably includes at least one structure selected from the group consisting of ethylene oxide structure, propylene oxide structure, polysiloxane structure and fluorinated alkylene structure.

[0241] SP21B is preferably a single bond or a straight-chain or branched alkylene group having 2 to 20 carbon atoms. However, the aforementioned alkylene group may contain -O-, -O-CO-, -CO-O-, or O-CO-O-.

[0242] In this regard, considering the increased orientation degree of the light-absorbing anisotropic layer, the spacer group represented by SP21B is preferably a single bond. In other words, the repeating unit 21 preferably has a structure in which the electron-withdrawing group EWG, as a group in formula (LCP-21), is directly connected to the mesocrystalline group MG21, as a group in formula (LCP-21). Thus, it is speculated that if the electron-withdrawing group is directly connected to the mesocrystalline group, the intermolecular interactions generated by the appropriate dipole moment in the polymer liquid crystal compound will function more effectively, thereby making the orientation of the liquid crystal more uniform. As a result, it is believed that the order degree of the liquid crystal is increased, and the orientation degree is also increased.

[0243] EWG indicates an electron-withdrawing group with a σp value greater than 0. Examples of electron-withdrawing groups with a σp value greater than 0 include ester groups (specifically, those derived from *-C(O)OR). E (represented by groups), (meth)acryloyl, (meth)acryloyloxy, carboxyl, cyano, nitro, sulfonyl, -S(O)(O)-OR E -S(O)(O)-R E -OS(O)(O)-R EAcyl group (specifically, composed of *-C(O)R) E The group represented), acyloxy group (specifically, represented by *-OC(O)R) E (represented by groups), isocyanate group (-N=C(O)), *-C(O)N(R) F 2. Halogen atoms and alkyl groups substituted by these groups (preferably with 1 to 20 carbon atoms). In the above groups, * indicates the bonding position with SP21B. R E R represents an alkyl group having 1 to 20 carbon atoms (preferably 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms). F Alkyl groups, each independently representing a hydrogen atom or a carbon atom number of 1 to 20 (preferably 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms).

[0244] Among the aforementioned groups, from the viewpoint of better maximizing the effects of the present invention, EWG is preferably composed of *-C(O)OR E The indicated groups are (meth)acryloyloxy or cyano, and nitro.

[0245] From the perspective of maintaining a high degree of orientation of the light-absorbing anisotropic layer and enabling the polymer liquid crystal compound and the dichroic material to be uniformly oriented, the content of repeating unit (21) relative to the total repeating units (100% by mass) of the polymer liquid crystal compound is preferably 60% by mass or less, more preferably 50% by mass or less, and even more preferably 45% by mass or less.

[0246] From the viewpoint of further maximizing the effects of the present invention, the lower limit of the content of repeating unit (21) is preferably 1% by mass or more, more preferably 3% by mass or more, relative to the total repeating units (100% by mass) of the polymer liquid crystal compound.

[0247] In this invention, the content of each repeating unit contained in the polymer liquid crystal compound is calculated based on the loading amount (mass) of each monomer used to obtain each repeating unit.

[0248] The polymeric liquid crystal compound may contain a single repeating unit (21) or two or more repeating units. If the polymeric liquid crystal compound contains two or more repeating units (21), it has advantages such as improved solubility in solvents and easier adjustment of the liquid crystal phase transition temperature. In the case of containing two or more repeating units (21), it is preferable that their total amount is within the above-mentioned range.

[0249] When two or more repeating units (21) are included, repeating units (21) that do not contain crosslinking groups in the EWG and repeating units (21) that contain polymerizable groups in the EWG can be used together. As a result, the curability of the light-absorbing anisotropic layer is further improved. In addition, as crosslinking groups, vinyl, butadiene, (meth)acrylate, (meth)acrylamide, vinyl acetate, fumarate, styrene, vinylpyrrolidone, maleic anhydride, maleimide, vinyl ether, epoxy, and oxetyl are preferred.

[0250] In this case, considering the balance between the curability and orientation of the light-absorbing anisotropic layer, the content of repeating units (21) containing polymeric groups in the EWG is preferably 1 to 30% by mass relative to the total repeating units (100% by mass) of the polymeric liquid crystal compound.

[0251] The following is an example of a repeating unit (21), but the repeating unit (21) is not limited to the following repeating units.

[0252] [Chemical Formula 13]

[0253]

[0254] Regarding the repeating unit (21) and repeating unit (22), the inventors conducted in-depth research on the composition (content ratio) and the electron-donating and electron-withdrawing properties of the terminal groups. The results showed that when the electron-withdrawing properties of the electron-withdrawing groups of the repeating unit (21) are strong (i.e., when the σp value is large), if the content ratio of the repeating unit (21) is reduced, the orientation degree of the light-absorbing anisotropic layer becomes higher. When the electron-withdrawing properties of the electron-withdrawing groups of the repeating unit (21) are weak (i.e., when the σp value is close to 0), if the content ratio of the repeating unit (21) is increased, the orientation degree of the light-absorbing anisotropic layer becomes higher.

[0255] While the detailed reasons are unclear, the general inference is as follows: It is speculated that through intermolecular interactions generated by moderate dipole moments in polymeric liquid crystal compounds, the orientation of the liquid crystal becomes more uniform. As a result, the degree of order of the liquid crystal is considered to be higher, and the orientation degree of the light-absorbing anisotropic layer becomes higher.

[0256] Specifically, the product of the σp value of the electron-withdrawing group (EWG in formula (LCP-21)) in the repeating unit (21) and the content ratio (mass basis) of the repeating unit (21) in the polymer liquid crystal compound is preferably 0.020 to 0.150, more preferably 0.050 to 0.130, and even more preferably 0.055 to 0.125. If the product is within the above range, the orientation degree of the light-absorbing anisotropic layer becomes higher.

[0257] The repeating unit (22) has a mesocrystalline group and a group with a σp value of 0 or less at the end of the mesocrystalline group. By having the repeating unit (22) in the polymer liquid crystal compound, the polymer liquid crystal compound and the dichroic material can be uniformly oriented.

[0258] Mesocrystalline groups are groups that represent the main framework of liquid crystal molecules that contribute to the formation of liquid crystals. Details are explained in MG of formula (LCP-22) described later, and specific examples are the same.

[0259] The aforementioned groups are those located at the end of mesocrystalline groups and have a σp value of 0 or less. Examples of such groups (groups with a σp value of 0 or less) include hydrogen atoms with a σp value of 0 and groups represented by T22 in the formula (LCP-22) described later, where the σp value is less than 0 (electron-donating groups). Specific examples of groups with a σp value less than 0 (electron-donating groups) are the same as T22 in the formula (LCP-22) described later.

[0260] The σp value of the above-mentioned groups is 0 or less. From the perspective of better orientation uniformity, it is preferable to be less than 0, more preferably less than -0.1, and even more preferably less than -0.2. The lower limit of the σp value of the above-mentioned groups is preferably more than -0.9, and more preferably more than -0.7.

[0261] The repeating unit (22) is not particularly limited as long as it has a mesocrystalline group in the side chain and a group with a σp value of 0 or less at the end of the mesocrystalline group. However, from the viewpoint of making the uniformity of liquid crystal orientation higher, it is preferable to have a repeating unit that does not correspond to the repeating unit represented by the above formula (LCP-21) and is represented by the following formula (PCP-22).

[0262] [Chemical Formula 14]

[0263]

[0264] In formula (LCP-22), PC22 represents the main chain of the repeating unit, more specifically, it represents the same structure as PC1 in formula (1) above; L22 represents a single bond or a divalent linker, more specifically, it represents the same structure as L1 in formula (1) above; SP22 represents a spacer, more specifically, it represents the same structure as SP1 in formula (1) above; MG22 represents a mesocrystalline structure, more specifically, it represents the same structure as the mesocrystalline group MG in formula (LC) above; and T22 represents an electron-donating group with a Hammett substituent constant σp value less than 0.

[0265] T22 indicates an electron-donating group with a σp value less than 0. Examples of electron-donating groups with a σp value less than 0 include hydroxyl groups, alkyl groups with 1 to 10 carbon atoms, alkoxy groups with 1 to 10 carbon atoms, and alkylamino groups with 1 to 10 carbon atoms.

[0266] By using T22 with a main chain of 20 or fewer atoms, the orientation degree of the anisotropic layer for light absorption is further improved. Here, "main chain" in T22 refers to the longest molecular chain bonded to MG22, and hydrogen atoms are not included in the number of atoms in the main chain of T22. For example, when T22 is n-butyl, the number of atoms in the main chain is 4, and when T22 is sec-butyl, the number of atoms in the main chain is 3.

[0267] The following is an example of a repeating unit (22), but the repeating unit (22) is not limited to the following repeating units.

[0268] [Chemical Formula 15]

[0269]

[0270] The repeating units (21) and (22) preferably share a portion of the same structure. It is speculated that the more similar the structures of the repeating units are to each other, the more uniformly the liquid crystals will be arranged. As a result, the orientation degree of the light-absorbing anisotropic layer becomes higher.

[0271] Specifically, considering that the orientation degree of the light absorption anisotropy layer becomes higher, it is preferable that at least one of the following is satisfied: SP21A of formula (LCP-21) and SP22 of formula (LCP-22) are the same structure; MG21 of formula (LCP-21) and MG22 of formula (LCP-22) are the same structure; and L21 of formula (LCP-21) and L22 of formula (LCP-22) are the same structure. More preferably, two or more are satisfied, and especially preferably all of them are satisfied.

[0272] From the perspective of excellent orientation uniformity, the content of repeating unit (22) is preferably 50% or more by mass relative to the total repeating units (100% by mass) of the polymer liquid crystal compound, more preferably 55% or more by mass, and especially preferably 60% or more by mass.

[0273] From the perspective of improving the degree of orientation, the upper limit of the content of repeating unit (22) is preferably 99% by mass or less, more preferably 97% by mass or less, relative to the total repeating units (100% by mass) of the polymer liquid crystal compound.

[0274] The polymeric liquid crystal compound may contain a single repeating unit (22) or two or more repeating units. If the polymeric liquid crystal compound contains two or more repeating units (22), it has advantages such as improved solubility in solvents and easier adjustment of the liquid crystal phase transition temperature. In the case of containing two or more repeating units (22), it is preferable that their total amount is within the above-mentioned range.

[0275] (Repeated unit (3))

[0276] From the perspective of improving solubility in general solvents, polymeric liquid crystal compounds can contain repeating units (3) that do not contain mesomorphic crystals. In particular, in order to suppress the decrease in orientation degree and improve solubility, the repeating unit (3) that does not contain mesomorphic crystals is preferably a repeating unit with a molecular weight of 280 or less. Thus, the reason for suppressing the decrease in orientation degree and improving solubility by containing repeating units with a molecular weight of 280 or less that do not contain mesomorphic crystals is as follows.

[0277] That is, it is believed that by including non-mesocrystalline repeating units (3) in the molecular chain of the polymer liquid crystal compound, the solvent can easily enter the polymer liquid crystal compound, thus increasing the solubility. However, the non-mesocrystalline repeating units (3) will cause the orientation degree to decrease. However, it is inferred that by having a small molecular weight, the orientation of the repeating units (1), repeating units (21) or repeating units (22) containing mesocrystalline groups is not easily disordered, which can suppress the decrease in orientation degree.

[0278] The repeating unit (3) is preferably a repeating unit with a molecular weight of 280 or less.

[0279] The molecular weight of the repeating unit (3) does not refer to the molecular weight of the monomer used to obtain the repeating unit (3), but rather to the molecular weight of the repeating unit (3) in the state of being incorporated into the polymer liquid crystal compound through the polymerization of the monomer.

[0280] The molecular weight of the repeating unit (3) is preferably 280 or less, more preferably 180 or less, and even more preferably 100 or less. The lower limit of the molecular weight of the repeating unit (3) is usually 40 or more, more preferably 50 or more. If the molecular weight of the repeating unit (3) is 280 or less, a light absorption anisotropic layer with excellent solubility and high orientation of the polymer liquid crystal compound can be obtained.

[0281] On the other hand, if the molecular weight of the repeating unit (3) exceeds 280, it leads to disordered liquid crystal orientation of the repeating unit (1), repeating unit (21), or repeating unit (22) and sometimes reduces the degree of orientation. Furthermore, since the solvent has difficulty entering the polymer liquid crystal compound, the solubility of the polymer liquid crystal compound sometimes decreases.

[0282] As specific examples of repeating unit (3), one can refer to repeating units that do not contain crosslinking groups (e.g., olefinic unsaturated groups) (hereinafter also referred to as "repeating unit (3-1)"). and repeating units that contain crosslinking groups (hereinafter also referred to as "repeating unit (3-2)").

[0283] • Repeating unit (3-1)

[0284] Specific examples of monomers used in the polymerization of repeating unit (3-1) include acrylic acid [72.1], α-alkyl acrylic acids (e.g., methacrylic acid [86.1], itaconic acid [130.1]), esters and amides derived from them (e.g., N-isopropylacrylamide [113.2], N-n-butylacrylamide [127.2], N-tert-butylacrylamide [127.2], N,N-dimethylacrylamide [99.1], N-methylmethacrylamide [99.1], acrylamide [71.1], methacrylamide [85.1], diacetone acrylamide [169.2], acryloylmorpholine [141.2], N-hydroxymethylacrylamide [101.1], N-hydroxy... Methyl methacrylamide [115.1], methyl acrylate [86.0], ethyl acrylate [100.1], hydroxyethyl acrylate [116.1], n-propyl acrylate [114.1], isopropyl acrylate [114.2], 2-hydroxypropyl acrylate [130.1], 2-methyl-2-nitropropyl acrylate [173.2], n-butyl acrylate [128.2], isobutyl acrylate [128.2], tert-butyl acrylate [128.2], tert-amyl acrylate [142.2], 2-methoxyethyl acrylate [130.1], 2-ethoxyethyl acrylate [144.2], 2-ethoxyethoxyethyl acrylate [188.2], 2,2,2-trifluoroethyl acrylate Ester [154.1], 2,2-dimethylbutyl acrylate [156.2], 3-methoxybutyl acrylate [158.2], ethyl carbitol acrylate [188.2], phenoxyethyl acrylate [192.2], n-amyl acrylate [142.2], n-hexyl acrylate [156.2], cyclohexyl acrylate [154.2], cyclopentyl acrylate [140.2], benzyl acrylate [162.2], n-octyl acrylate [184.3], 2-ethylhexyl acrylate [184.3], 4-methyl-2-propylpentyl acrylate [198.3], methyl methacrylate [100.1], 2,2,2-trifluoroethyl methacrylate [168.1], hydroxyethyl methacrylate Esters [130.1], 2-hydroxypropyl methacrylate [144.2], n-butyl methacrylate [142.2], isobutyl methacrylate [142.2], sec-butyl methacrylate [142.2], octyl methacrylate [198.3], 2-ethylhexyl methacrylate [198.3], 2-methoxyethyl methacrylate [144.2], 2-ethoxyethyl methacrylate [158.2], benzyl methacrylate [176.2], 2-norbornyl methyl methacrylate [194.3], 5-norbornen-2-yl methyl methacrylate [194.3], dimethylaminoethyl methacrylate [157.2]), vinyl esters (e.g., vinyl acetate [86.1) Esters derived from maleic acid or fumaric acid (e.g., dimethyl maleate [144.1], diethyl fumarate [172.2]), maleimides (e.g., N-phenylmaleimide [173.2]), maleic acid [116.1], fumaric acid [116.1], p-styrenesulfonic acid [184.1], acrylonitrile [53.1], methacrylonitrile [67.1], dienes (e.g., butadiene [54.1], cyclopentadiene [66.1], isoprene [68.1]), aromatic vinyl compounds (e.g., styrene [104.2], p-chlorostyrene [138.6], tert-butylstyrene [160.3], α-methylstyrene [118.2]), N-vinylpyrrolidone [111.1], N-ethylene N-vinyl oxazolidinone [113.1], N-vinylsuccinimide [125.1], N-vinylformamide [71.1], N-vinyl-N-methylformamide [85.1], N-vinylacetamide [85.1], N-vinyl-N-methylacetamide [99.1], 1-vinylimidazolium [94.1], 4-vinylpyridine [105.2], vinyl sulfonic acid [108.1], sodium vinyl sulfonate [130.2], sodium allyl sulfonate [144.1], sodium methyl allyl sulfonate [158.2], vinylidene chloride [96.9], vinyl alkyl ethers (e.g., methyl vinyl ether [58.1]), ethylene [28.0], propylene [42.1], 1-butene [56.1], and isobutene [56.1]. Additionally, the values ​​in brackets [] refer to the molecular weight of the monomer.

[0285] The above-mentioned monomers can be used alone or in combination of two or more.

[0286] Among the monomers mentioned above, acrylic acid, α-alkyl acrylic acids, esters and amides derived from them, acrylonitrile, methacrylonitrile, and aromatic vinyl compounds are preferred.

[0287] Other than the monomers mentioned above, for example, compounds described in Research Disclosure No. 1955 (July 1980) can be used.

[0288] The following examples of repeating units (3-1) and their molecular weights are shown, but the present invention is not limited to these specific examples.

[0289] [Chemical Formula 16]

[0290]

[0291] • Repeating unit (3-2)

[0292] In the repeating unit (3-2), specific examples of crosslinking groups can be the groups represented by the above formulas (P-1) to (-P30), more preferably vinyl, butadiene, (meth)acrylic acid, (meth)acrylamide, vinyl acetate, fumarate, styrene, vinylpyrrolidone, maleic anhydride, maleimide, vinyl ether, epoxy, and oxetyl.

[0293] From the perspective of ease of aggregation, the repeating unit (3-2) is preferably a repeating unit represented by the following formula (3).

[0294] [Chemical Formula 17]

[0295]

[0296] In the above formula (3), PC32 represents the main chain of the repeating unit, more specifically, it represents the same structure as PC1 in the above formula (1), L32 represents a single bond or a divalent linker, more specifically, it represents the same structure as L1 in the above formula (1), and P32 represents the crosslinking group represented by the above formulas (P1) to (P30).

[0297] The following examples of repeating units (3-2) and their molecular weights (Mw) are shown, but the present invention is not limited to these specific examples.

[0298] [Chemical Formula 18]

[0299]

[0300] The content of repeating unit (3) is preferably less than 14% by mass relative to the total repeating units (100% by mass) of the polymeric liquid crystal compound, more preferably less than 7% by mass, and even more preferably less than 5% by mass. The lower limit of the content of repeating unit (3) is preferably more than 2% by mass relative to the total repeating units (100% by mass) of the polymeric liquid crystal compound, more preferably more than 3% by mass. If the content of repeating unit (3) is less than 14% by mass, the orientation degree of the light-absorbing anisotropic layer is further improved. If the content of repeating unit (3) is more than 2% by mass, the solubility of the polymeric liquid crystal compound is further improved.

[0301] The polymer liquid crystal compound may contain a single repeating unit (3) or two or more repeating units. When two or more repeating units (3) are contained, it is preferable that their total amount is within the above range.

[0302] (Repeated unit (4))

[0303] From the perspective of improving adhesion and surface uniformity, polymeric liquid crystal compounds can contain repeating units (4) with a flexible structure having a molecular chain length (SP4 of formula (4) described later). The reason for this is as follows.

[0304] That is, by incorporating a flexible structure with such long molecular chains, the molecular chains constituting the liquid crystal compound easily become entangled with each other, thus suppressing the cohesive breakdown of the light absorption anisotropic layer (specifically, the light absorption anisotropic layer itself is destroyed). As a result, it is presumed that the adhesion between the light absorption anisotropic layer and the substrate layer (e.g., a substrate or alignment film) is improved. Furthermore, it is believed that the decrease in planar uniformity is due to the low compatibility between the dichroic material and the liquid crystal compound. That is, it is believed that if the compatibility between the dichroic material and the liquid crystal compound is insufficient, planar defects (alignment defects) with the precipitated dichroic material as the core will occur. In this regard, it is presumed that by incorporating a flexible structure with long molecular chains in the liquid crystal compound, the precipitation of the dichroic material is suppressed, thereby obtaining a light absorption anisotropic layer with excellent planar uniformity. Here, excellent planar uniformity means fewer alignment defects caused by the liquid crystal composition containing the liquid crystal compound being repelled on the substrate layer (e.g., a substrate or alignment film).

[0305] The repeating unit (4) mentioned above is a repeating unit represented by the following formula (4).

[0306] [Chemical Formula 19]

[0307]

[0308] In the above formula (4), PC4 represents the main chain of the repeating unit, more specifically, it represents the same structure as PC1 in the above formula (1), L4 represents a single bond or a divalent linker, more specifically, it represents the same structure as L1 in the above formula (1) (preferably a single bond), SP4 represents an alkylene group with 10 or more atoms in the main chain, and T4 represents a terminal group, more specifically, it represents the same structure as T1 in the above formula (1).

[0309] The specific example and preferred method of PC4 are the same as PC1 in equation (1), so its description is omitted.

[0310] From the perspective of maximizing the effects of the present invention, a single bond is preferred as L4.

[0311] In formula (4), SP4 represents an alkylene group with 10 or more atoms in the main chain. However, one or more -CH2- atoms constituting the alkylene group represented by SP4 can be replaced by the aforementioned "SP-C", and is particularly preferably selected from -O-, -S-, and -N(R). 21 )-, -C(=O)-, -C(=S)-, -C(R 22 )=C(R23 -, ynyne, -Si(R) 24 (R) 25 -, -N=N-, -C(R) 26 )=NN=C(R 27 )-、-C(R 28 At least one group from the group consisting of -N- and -S(=O)2- is substituted. However, R 21 ~R 28 Each of these can independently represent a hydrogen atom, a halogen atom, a cyano group, a nitro group, or a straight-chain or branched alkyl group having 1 to 10 carbon atoms. Furthermore, the hydrogen atoms contained in one or more -CH2- groups constituting the alkylene group represented by SP4 can be replaced by the aforementioned "SP-H".

[0312] The main chain of SP4 has 10 or more atoms, and from the viewpoint of obtaining a light absorption anisotropic layer with better at least one of superior adhesion and planar uniformity, it is preferably 15 or more, more preferably 19 or more. Furthermore, from the viewpoint of obtaining a light absorption anisotropic layer with better orientation, the upper limit of the main chain of SP2 is preferably 70 or less, more preferably 60 or less, and even more preferably 50 or less.

[0313] Here, the "main chain" in SP4 refers to the partial structure required to directly connect L4 and T4, and the "number of atoms in the main chain" refers to the number of atoms constituting the aforementioned partial structure. In other words, the "main chain" in SP4 is the partial structure where the number of atoms connecting L4 and T4 is the shortest. For example, the number of atoms in the main chain of SP4 when it is 3,7-dimethyldecyl is 10, and the number of atoms in the main chain of SP4 when it is 4,6-dimethyldodecyl is 12. Furthermore, in the following formula (4-1), the box represented by the dotted quadrilateral corresponds to SP4, and the number of atoms in the main chain of SP4 (equivalent to the total number of atoms enclosed by the dotted circle) is 11.

[0314] [Chemical Formula 20]

[0315]

[0316] The alkylene group represented by SP4 can be either straight-chain or branched.

[0317] From the perspective of obtaining a light absorption anisotropic layer with better orientation, the number of carbon atoms of the alkylene group represented by SP4 is preferably 8 to 80, more preferably 15 to 80, even more preferably 25 to 70, and particularly preferably 25 to 60.

[0318] From the perspective of obtaining a light absorption anisotropic layer with better adhesion and planar uniformity, one or more -CH2- atoms constituting the alkylene group represented by SP4 are preferably replaced by the above-mentioned "SP-C".

[0319] Furthermore, in the case of having multiple -CH2- groups constituting SP4, from the perspective of obtaining a light absorption anisotropic layer with better adhesion and planar uniformity, it is more preferable that only a portion of the multiple -CH2- groups are replaced by the aforementioned "SP-C".

[0320] In “SP-C”, the preferred selections are -O-, -S-, and -N(R). 21 )-, -C(=O)-, -C(=S)-, -C(R 22 )=C(R 23 -, ynyne, -Si(R) 24 (R) 25 -, -N=N-, -C(R) 26 )=NN=C(R 27 )-、-C(R 28 At least one group from the group consisting of -O- and -S(=O)2- is preferred, considering the possibility of obtaining a light absorption anisotropic layer with better adhesion and planar uniformity. 21 At least one group selected from the group consisting of -O-, -C(=O)- and -S(=O)2-, particularly preferably selected from the group consisting of -O-, -N(R)-, -C(=O)-, and -S(=O)2-. 21 At least one group from the group consisting of -C(=O)- and -C(=O)-.

[0321] In particular, SP4 is preferably a group comprising at least one of the following groups: an alkylene oxide structure comprising one or more -CH2-substituted -O-, an ester structure comprising one or more -CH2-CH2-substituted -O- and -C(=O)-, and a urethane bond comprising one or more -CH2-CH2-CH2-substituted -O-, -C(=O)- and -NH-.

[0322] One or more hydrogen atoms in the -CH2- group constituting the alkylene group represented by SP4 can be replaced by the aforementioned "SP-H". In this case, it is sufficient for one or more hydrogen atoms in the -CH2- group to be replaced by "SP-H". That is, it is possible for only one hydrogen atom in the -CH2- group to be replaced by "SP-H", or it is possible for all two hydrogen atoms in the -CH2- group to be replaced by "SP-H".

[0323] In “SP-H”, preferably, at least one group is selected from the group consisting of halogen atom, cyano, nitro, hydroxyl, straight-chain alkyl with 1 to 10 carbon atoms and branched alkyl with 1 to 10 carbon atoms, and haloalkyl with 1 to 10 carbon atoms. More preferably, at least one group is selected from the group consisting of hydroxyl, straight-chain alkyl with 1 to 10 carbon atoms and branched alkyl with 1 to 10 carbon atoms.

[0324] As described above, T4 represents the same terminal group as T1, preferably a hydrogen atom, methyl, hydroxyl, carboxyl, sulfonic acid, phosphoric acid, boric acid, amino, cyano, nitro, or a phenyl group that may have substituents, or -L-CL (L represents a single bond or a divalent linker. Specific examples of divalent linkers are the same as those for LW and SPW described above. CL represents a crosslinking group, and examples include groups represented by Q1 or Q2 described above, preferably crosslinking groups represented by formulas (P1) to (P30) described above). As the CL described above, vinyl, butadiene, (meth)acryloyl, (meth)acrylamido, vinyl acetate, fumarate, styrene, vinylpyrrolidone, maleic anhydride, maleimide, vinyl ether, epoxy, or oxetyl are preferred.

[0325] The epoxy group can be an epoxycycloalkyl group. From the perspective of further improving the effect of the present invention, the number of carbon atoms in the cycloalkyl part of the epoxycycloalkyl group is preferably 3 to 15, more preferably 5 to 12, and even more preferably 6 (i.e., the case where the epoxycycloalkyl group is an epoxycyclohexyl group).

[0326] Examples of substituents for the oxetyl group include alkyl groups having 1 to 10 carbon atoms; however, for better performance of the present invention, alkyl groups having 1 to 5 carbon atoms are preferred. The alkyl group used as a substituent for the oxetyl group can be linear or branched; however, for better performance of the present invention, a linear form is preferred.

[0327] Examples of substituents for phenyl groups include borate, sulfonic acid, vinyl, and amino groups. From the perspective of better performance of the present invention, borate is preferred.

[0328] Specific examples of the repeating unit (4) include the following structures, but the invention is not limited to these. Furthermore, in the following specific examples, n1 represents an integer greater than 2, and n2 represents an integer greater than 1.

[0329] [Chemical Formula 21]

[0330]

[0331] The content of the repeating unit (4) is preferably 2 to 20% by mass, more preferably 3 to 18% by mass, relative to the total repeating units (100% by mass) of the polymer liquid crystal compound. If the content of the repeating unit (4) is 2% by mass or more, a light absorption anisotropic layer with better adhesion can be obtained. Furthermore, if the content of the repeating unit (4) is 20% by mass or less, a light absorption anisotropic layer with better planar uniformity can be obtained.

[0332] The polymer liquid crystal compound may contain a single repeating unit (4) or two or more repeating units (4). In the case of containing two or more repeating units (4), the content of the repeating unit (4) refers to the total content of the repeating units (4).

[0333] (Repeated unit (5))

[0334] From the viewpoint of planar uniformity, the polymer liquid crystal compound can contain repeating units (5) introduced by polymerizing the multifunctional monomer. In particular, in order to suppress the decrease in orientation degree and improve planar uniformity, it is preferable to contain 10% by mass or less of repeating units (5) introduced by polymerizing the multifunctional monomer. Thus, the reason for suppressing the decrease in orientation degree and improving planar uniformity by containing 10% by mass or less of repeating units (5) is as follows.

[0335] The repeating unit (5) is a unit introduced into the polymer liquid crystal compound to facilitate the polymerization of multifunctional monomers. Therefore, it is considered that the polymer liquid crystal compound contains a high molecular weight body with a three-dimensional cross-linked structure formed by the repeating unit (5). Here, since the content of the repeating unit (5) is small, it is considered that the content of the high molecular weight body containing the repeating unit (5) is low.

[0336] Thus, it is speculated that by the presence of a small amount of high molecular weight bodies with three-dimensional cross-linked structures, the repulsion of the liquid crystal composition is suppressed, thereby obtaining a light absorption anisotropic layer with excellent planar uniformity.

[0337] Furthermore, since the content of high molecular weight polymers is small, it is speculated that this can maintain the effect of inhibiting the decrease in orientation.

[0338] The repeating unit (5) introduced by the polymerization of the multifunctional monomer is preferably a repeating unit represented by the following formula (5).

[0339] [Chemical Formula 22]

[0340]

[0341] In equation (5), PC5A and PC5B represent the main chain of repeating units, more specifically, they represent the same structure as PC1 in equation (1) above. L5A and L5B represent single bonds or divalent linkers, more specifically, they represent the same structure as L1 in equation (1) above. SP5A and SP5B represent spacer groups, more specifically, they represent the same structure as SP1 in equation (1) above. MG5A and MG5B represent mesocrystalline structures, more specifically, they represent the same structure as the mesocrystalline group MG in equation (LC) above. a and b represent integers 0 or 1.

[0342] PC5A and PC5B can be the same group or different groups, but from the perspective of further improving the orientation degree of the light absorption anisotropy layer, the same group is preferred.

[0343] L5A and L5B can both be single bonds, or they can be the same group, or they can be different groups. However, from the perspective of further improving the orientation degree of the light absorption anisotropy layer, they are both preferably single bonds or the same group, and more preferably the same group.

[0344] SP5A and SP5B can both be single bonds, or they can be the same group, or they can be different groups. However, considering the further improvement of the orientation degree of the light absorption anisotropy layer, they are both preferably single bonds or the same group, and more preferably the same group.

[0345] Here, the same group in formula (5) refers to groups with the same chemical structure regardless of their bonding orientation. For example, SP5A is *-CH2-CH2-O-** (* indicates the bonding position with L5A, and ** indicates the bonding position with MG5A.) and SP5B is *-O-CH2-CH2-** (* indicates the bonding position with MG5B, and ** indicates the bonding position with L5B.) which also constitutes the same group.

[0346] a and b are independent integers of 0 or 1, and from the perspective of further improving the orientation degree of the light absorption anisotropic layer, 1 is preferred.

[0347] a and b can be the same or different, but considering the further improvement of the orientation degree of the light absorption anisotropic layer, 1 is preferred.

[0348] From the perspective of further improving the orientation degree of the light-absorbing anisotropic layer, the total of a and b is preferably 1 or 2 (i.e., the repeating unit represented by formula (5) has a mesocrystalline group), more preferably 2.

[0349] Considering further improvements in the orientation degree of the light-absorbing anisotropic layer, from -(MG5A) a -(MG5B)b The structure indicated by - preferably has a ring-like structure. In this case, considering the further improvement of the orientation degree of the light-absorbing anisotropic layer, -(MG5A2) a -(MG5B) b - The number of ring structures in the partial structure is preferably 2 or more, more preferably 2 to 8, even more preferably 2 to 6, and especially preferably 2 to 4.

[0350] From the perspective of further improving the orientation degree of the light absorption anisotropic layer, the mesocrystalline groups represented by MG5A and MG5B each preferably contain one or more ring structures, preferably two to four, more preferably two to three, and especially preferably two.

[0351] Specific examples of cyclic structures include aromatic hydrocarbon groups, heterocyclic groups, and alicyclic groups, with aromatic hydrocarbon groups and alicyclic groups being preferred.

[0352] MG5A and MG5B can be the same group or different groups, but from the perspective of further improving the orientation degree of the light absorption anisotropy layer, the same group is preferred.

[0353] From the viewpoints of exhibiting liquid crystal properties, adjusting liquid crystal phase transition temperature, raw material availability, and suitability for synthesis, as well as from the viewpoint of achieving better results in this invention, the mesocrystalline group MG in the above formula (LC) is preferred as the mesocrystalline group represented by MG5A and MG5B.

[0354] In particular, the repeating unit (5) preferably has PC5A and PC5B as the same group, L5A and L5B as single bonds or the same group, SP5A and SP5B as single bonds or the same group, and MG5A and MG5B as the same group. This further improves the orientation degree of the light absorption anisotropy layer.

[0355] The content of repeating unit (5) relative to the content of all repeating units (100% by mass) in the polymer liquid crystal compound is preferably 10% by mass or less, more preferably 0.001 to 5% by mass, and even more preferably 0.05 to 3% by mass.

[0356] The polymer liquid crystal compound may contain a single repeating unit (5) or two or more repeating units. When two or more repeating units (5) are contained, it is preferable that their total amount is within the above-mentioned range.

[0357] (Star-shaped polymer)

[0358] The polymeric liquid crystal compound can be a star polymer. In this invention, a star polymer refers to a polymer having three or more polymer chains extending from a core, specifically represented by the following formula (6).

[0359] As a liquid crystal polymer, the star-shaped polymer represented by formula (6) has high solubility (excellent solubility in solvents) and can form a light-absorbing anisotropic layer with high orientation.

[0360] [Chemical Formula 23]

[0361]

[0362] In equation (6), n A Represents an integer greater than 3, preferably an integer greater than 4. A The upper limit is not limited to this, but it is usually below 12, preferably below 6.

[0363] Each of the plurality of PIs independently represents a polymer chain containing any one of the repeating units represented by equations (1), (21), (22), (3), (4), and (5) above. However, at least one of the plurality of PIs represents a polymer chain containing the repeating unit represented by equation (1) above.

[0364] A represents the atomic group that forms the core of the star-shaped polymer. Specific examples of A include paragraphs

[0052] to

[0058] of Japanese Patent Application Publication No. 2011-074280, paragraphs

[0017] to

[0021] of Japanese Patent Application Publication No. 2012-189847, paragraphs

[0012] to

[0024] of Japanese Patent Application Publication No. 2013-031986, and paragraphs

[0118] to

[0142] of Japanese Patent Application Publication No. 2014-104631, which describe structures in which hydrogen atoms have been removed from the thiol group of a polyfunctional thiol compound. In this case, A and PI are bonded via a thioether bond.

[0365] The polyfunctional thiol compound that becomes the source of A preferably has 3 or more thiol groups, more preferably 4 or more. The upper limit for the number of thiol groups in the polyfunctional thiol compound is generally 12 or less, preferably 6 or less.

[0366] The following are specific examples of polyfunctional thiols.

[0367] [Chemical Formula 24]

[0368]

[0369] From the perspective of improving orientation, polymeric liquid crystal compounds can be thermotropic liquid crystals and crystalline polymers.

[0370] (Thermotropic liquid crystals)

[0371] Thermotropic liquid crystals are liquid crystals that exhibit a transition to a liquid crystal phase through temperature changes.

[0372] The polymer liquid crystal compound is a thermotropic liquid crystal that can display either a nematic phase or a smectic phase. However, considering reasons such as making the haze more difficult to observe (or making the haze better), it is preferable to display at least a nematic phase.

[0373] From the perspective that the orientation degree of the light-absorbing anisotropic layer becomes higher and the haze becomes more difficult to observe, the temperature range for displaying the nematic phase is preferably (23°C) to 450°C, and more preferably (40°C to 400°C) from the viewpoint of processing and manufacturing applicability.

[0374] (Crystall polymer)

[0375] Crystalline polymers are polymers that exhibit a transformation towards a crystalline layer when temperature changes occur. In addition to this transformation, crystalline polymers can also exhibit a glass transition.

[0376] Considering that the orientation degree of the light absorption anisotropy layer becomes higher and the haze becomes more difficult to observe, the crystalline polymer is preferably a polymeric liquid crystal compound that undergoes a transition from a crystalline phase to a liquid crystal phase upon heating (with a possible glass transition in between) or a polymeric liquid crystal compound that undergoes a transition from a crystalline phase to a crystalline phase upon cooling after being heated to a liquid crystal state (with a possible glass transition in between).

[0377] In addition, the crystallinity of polymeric liquid crystal compounds is evaluated in the following manner.

[0378] Two anisotropic light-absorbing layers of an optical microscope (NIKON Co., Ltd. ECLIPSE E600POL) were arranged orthogonally, and a sample stage was fixed between the two layers. A small amount of a polymeric liquid crystal compound was then placed on a glass slide, which was then fixed to a heated stage on the sample stage. While observing the sample's state, the temperature of the heated stage was increased to the temperature at which the polymeric liquid crystal compound exhibited liquidometry, thus precipitating it into a liquid crystal state. After the polymeric liquid crystal compound reached the liquid crystal state, the liquid crystal phase transition behavior was observed while gradually decreasing the temperature of the heated stage, and the phase transition temperatures were recorded. Furthermore, when the polymeric liquid crystal compound exhibited multiple liquid crystal phases (e.g., nematic and smectic phases), all their transition temperatures were also recorded.

[0379] Next, approximately 5 mg of the polymeric liquid crystal compound sample was placed in an aluminum dish, covered, and fixed in a differential scanning calorimeter (DSC) (using an empty aluminum dish as a reference). The sample was heated to the temperature at which the polymeric liquid crystal compound exhibited its liquid crystal phase as determined above, and then held at that temperature for 1 minute. Then, the temperature was lowered at a rate of 10 °C / min while calorimetric measurements were performed. The calorimetric peak was confirmed from the obtained calorimetric spectrum.

[0380] As a result, when a heating peak is observed at temperatures other than the liquid crystal phase transition temperature, this heating peak is a peak generated by crystallization, indicating that the polymer liquid crystal compound has crystallinity.

[0381] On the other hand, if no heating peak is observed at temperatures other than the liquid crystal phase transition temperature, it can be said that the polymer liquid crystal compound does not have crystallinity.

[0382] There are no particular limitations on the method for obtaining crystalline polymers. As a specific example, it is preferable to use a method that uses a polymeric liquid crystal compound containing the repeating unit (1) described above. More preferably, it is preferable to use a method that uses a polymeric liquid crystal compound containing the repeating unit (1) described above.

[0383] Crystallization temperature

[0384] From the perspective of achieving a higher degree of orientation in the light-absorbing anisotropic layer and making haze more difficult to observe, the crystallization temperature of the polymeric liquid crystal compound is preferably -50°C or higher and less than 150°C, more preferably 120°C or lower, even more preferably -20°C or higher and less than 120°C, and particularly preferably 95°C or lower. From the viewpoint of reducing haze, the crystallization temperature of the aforementioned polymeric liquid crystal compound is preferably less than 150°C.

[0385] In addition, the crystallization temperature is based on the temperature of the exothermic peak of crystallization in the DSC mentioned above.

[0386] (molecular weight)

[0387] From the perspective of further improving the effects of the present invention, the weight-average molecular weight (Mw) of the polymeric liquid crystal compound is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. If the Mw of the polymeric liquid crystal compound is within the above range, the polymeric liquid crystal compound is easier to process.

[0388] In particular, from the viewpoint of suppressing cracks during coating, the weight-average molecular weight (Mw) of the polymer liquid crystal compound is preferably 10,000 or more, and more preferably 10,000 to 300,000.

[0389] Furthermore, from the viewpoint of temperature tolerance of orientation, the weight-average molecular weight (Mw) of the polymer liquid crystal compound is preferably less than 10,000, and preferably more than 2,000 and less than 10,000.

[0390] In this invention, the weight-average molecular weight and number-average molecular weight are values ​​determined by gel permeation chromatography (GPC).

[0391] • Solvent (eluent): N-methylpyrrolidone

[0392] • Device Name: TOSOH HLC-8220GPC

[0393] • Column: Connect 3 TOSOH TSKgelSuperAWM-H (6mm×15cm) for use.

[0394] Column temperature: 25℃

[0395] • Sample concentration: 0.1% by mass

[0396] • Flow rate: 0.35 ml / min

[0397] • Calibration curve: The calibration curve was obtained using seven samples of TSK standard polystyrene prepared by TOSOH with Mw = 2,800,000 to 1,050 (Mw / Mn = 1.03 to 1.06).

[0398] The liquid crystal properties of polymeric liquid crystal compounds can exhibit either nematic or smectic properties, but preferably at least nematic properties.

[0399] The preferred temperature range for the nematic phase is 0°C to 450°C, and from the viewpoint of processing and manufacturing suitability, it is preferably 30°C to 400°C.

[0400] The content of the liquid crystal compound relative to the content of the dichroic substance in the liquid crystal composition is preferably 25 to 2000 parts by mass, more preferably 100 to 1300 parts by mass, and even more preferably 200 to 900 parts by mass. With the liquid crystal compound content within the above range, the orientation degree of the polarizer is further improved.

[0401] 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 refers to the total content of the liquid crystal compounds.

[0402] [Dichroic substances]

[0403] The light-absorbing anisotropic layer used in this invention contains a dichroic material.

[0404] There are no particular limitations on dichroic substances. Examples include visible light absorbing substances (dichroic substances, dichroic azo compounds), luminescent substances (fluorescent substances, phosphorescent substances), ultraviolet light absorbing substances, infrared light absorbing substances, nonlinear optical substances, carbon nanotubes, inorganic substances (such as quantum rods), etc. Previously known dichroic substances (dichroic pigments, dichroic dyes) can also be used.

[0405] The preferred dichroic substance used is an organic dichroic compound, and more preferably a dichroic azo dye compound.

[0406] There are no particular limitations on the dichroic azo dye compound; conventionally known dichroic azo dyes can be used, but compounds described later are preferred.

[0407] In this invention, dichroic azo pigment compounds refer to pigments whose absorbance varies depending on the direction.

[0408] Dichroic azo dye compounds may or may not exhibit liquid crystal properties.

[0409] 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°C to 28°C) to 300°C, and more preferably 50°C to 200°C from the viewpoint of processability and manufacturing suitability.

[0410] In this invention, from the viewpoint of adjusting hue, the light-absorbing anisotropic layer preferably has at least one pigment compound (hereinafter also referred to as "first dichroic azo pigment compound") having a maximum absorption wavelength in the wavelength range of 560 to 700 nm and at least one pigment compound (hereinafter also referred to as "second dichroic azo pigment compound") having a maximum absorption wavelength in the wavelength range of 455 nm or more and less than 560 nm. More preferably, it has at least the dichroic azo pigment compound represented by formula (1) described later and the dichroic azo pigment compound represented by formula (2) described later.

[0411] In this invention, three or more dichroic azo pigment compounds may be used together. For example, from the viewpoint of making the light absorption anisotropic layer close to black, it is preferable to use a first dichroic azo pigment compound, a second dichroic azo pigment compound, and at least one pigment compound having a maximum absorption wavelength in the range of 380 nm or more and less than 455 nm (hereinafter also simply referred to as "the third dichroic azo pigment compound").

[0412] That is, in this invention, the light absorption anisotropic layer preferably contains two or more organic dichroic pigments with different absorption peak wavelengths, and more preferably contains three or more organic dichroic pigments with different absorption peak wavelengths.

[0413] In this invention, from the viewpoint of improving compressive strength, it is preferable that the dichromatic azo dye compound has crosslinking groups.

[0414] As a crosslinking group, examples include (meth)acryloyl, epoxy, oxocyclobutyl, styryl, etc., with (meth)acryloyl being preferred.

[0415] (First dichroic azo pigment compound)

[0416] The first dichroic azo dye compound is preferably a compound having a chromophore as a core and a side chain bonded to the end of the chromophore.

[0417] Specific examples of chromophores include aromatic cyclic groups (e.g., aromatic hydrocarbon groups, aromatic heterocyclic groups), azo groups, etc., preferably having both an aromatic cyclic group and an azo group, and more preferably having a bisazo structure having an aromatic heterocyclic group (preferably thienothiazolyl) and two azo groups.

[0418] As a side chain, there are no particular limitations, and examples can be groups represented by L3, R2 or L4 of formula (1) described later.

[0419] The first dichroic azo dye compound is a dichroic azo dye compound having a maximum absorption wavelength in the range of 560 nm to 700 nm. From the viewpoint of adjusting the hue of the polarizer, it is preferable to have a dichroic azo dye compound having a maximum absorption wavelength in the range of 560 to 650 nm, and more preferably to have a dichroic azo dye compound having a maximum absorption wavelength in the range of 560 to 640 nm.

[0420] The maximum absorption wavelength (nm) of the dichroic azo dye compound in this specification is determined by using a solution prepared by dissolving the dichroic azo dye compound in a good solvent and measuring the ultraviolet-visible spectrum in the wavelength range of 380–800 nm using a spectrophotometer.

[0421] In this invention, considering the need to further improve the orientation of the formed light-absorbing anisotropic layer, the first dichroic azo dye compound is preferably a compound represented by the following formula (1).

[0422] [Chemical Formula 25]

[0423]

[0424] In formula (1), Ar1 and Ar2 independently represent either a phenylene group that may have substituents or a naphthylene group that may have substituents, with phenylene being preferred.

[0425] In formula (1), R1 represents a straight-chain or branched alkyl, alkoxy, alkylthio, alkylsulfonyl, alkylcarbonyl, alkoxycarbonyl, acyloxy, alkyl carbonate, alkylamino, acylamino, alkylcarbonylamino, alkoxycarbonylamino, alkylsulfonylamino, alkylaminosulfonyl, alkylcarbamoyl, alkylsulfinyl, alkylurea, alkylphosphamide, alkylimino or alkylsilyl.

[0426] The -CH2- group constituting the above alkyl group can be substituted with -O-, -CO-, -C(O)-O-, -OC(O)-, -Si(CH3)2-O-Si(CH3)2-, -N(R1')-, -N(R1')-CO-, -CO-N(R1')-, -N(R1')-C(O)-O-, -OC(O)-N(R1')-C(O)-N(R1')-, -CH=CH-, -C≡C-, -N=N-, -C(R1')=CH-C(O)- or -OC(O)-O-.

[0427] When R1 is a group other than a hydrogen atom, the hydrogen atom in each group can be replaced by a halogen atom, nitro group, cyano group, -N(R1')2, amino group, -C(R1')=C(R1')-NO2, -C(R1')=C(R1')-CN or -C(R1')=C(CN)2.

[0428] R1' represents a straight-chain or branched alkyl group with 1 to 6 carbon atoms or hydrogen atoms. When multiple R1's exist in various groups, they can be the same or different from each other.

[0429] In formula (1), R2 and R3 independently represent hydrogen atoms and straight-chain or branched alkyl, alkoxy, acyl, alkoxycarbonyl, alkylamide, alkylsulfonyl, aryl, arylcarbonyl, arylsulfonyl, aryloxycarbonyl or arylamide groups with 1 to 20 carbon atoms that may have substituents.

[0430] The -CH2- group constituting the above alkyl group can be replaced by -O-, -S-, -C(O)-, -C(O)-O-, -OC(O)-, -C(O)-S-, -SC(O)-, -Si(CH3)2-O-Si(CH3)2-, -NR2'-, -NR2'-CO-, -CO-NR2'-, -NR2'-C(O)-O-, -OC(O)-NR2'-, -NR2'-C(O)-NR2'-, -CH=CH-, -C≡C-, -N=N-, -C(R2')=CH-C(O)- or -OC(O)-O-.

[0431] When R2 and R3 are groups other than hydrogen atoms, the hydrogen atoms in each group can be replaced by halogen atoms, nitro groups, cyano groups, -OH groups, -N(R2')2, amino groups, -C(R2')=C(R2')-NO2, -C(R2')=C(R2')-CN, or -C(R2')=C(CN)2.

[0432] R2' represents a straight-chain or branched alkyl group with 1 to 6 carbon atoms or hydrogen atoms. When multiple R2's exist in various groups, they can be the same or different from each other.

[0433] R2 and R3 can bond with each other to form a ring, and R2 or R3 can also bond with Ar2 to form a ring.

[0434] From the viewpoint of lightfastness, R1 is preferably an electron-withdrawing group, and R2 and R3 are preferably groups with low electron-donating properties.

[0435] Specific examples of such groups include alkylsulfonyl, alkylcarbonyl, alkoxycarbonyl, acyloxy, alkylsulfonylamino, alkylaminosulfonyl, alkylsulfinyl, and alkylurea groups as R1, and groups with the following structures as R2 and R3. Furthermore, the groups with the following structures are represented in the above formula (1) in the form of containing the nitrogen atoms bonded to R2 and R3.

[0436] [Chemical Formula 26]

[0437]

[0438] The following are specific examples of the first dichroic azo dye compound, but are not limited thereto.

[0439] [Chemical Formula 27]

[0440]

[0441]

[0442] (Second dichroic azo pigment compound)

[0443] The second dichroic azo dye compound is a different compound from the first dichroic azo dye compound; specifically, it has a different chemical structure.

[0444] The second dichroic azo pigment compound is preferably a compound having a chromophore as the core of the dichroic azo pigment compound and a side chain bonded to the end of the chromophore.

[0445] Specific examples of chromophores include aromatic cyclic groups (e.g., aromatic hydrocarbon groups, aromatic heterocyclic groups), azo groups, etc., preferably having both an aromatic hydrocarbon group and an azo group, and more preferably having a diazo or triazo structure having an aromatic hydrocarbon group and 2 or 3 azo groups.

[0446] As a side chain, there are no particular limitations, and examples can be the groups represented by R4, R5 or R6 of formula (2) described later.

[0447] The second dichroic azo dye compound is a dichroic azo dye compound having a maximum absorption wavelength in the range of 455 nm or higher and less than 560 nm. From the viewpoint of adjusting the hue of the polarizer, it is preferable to have a dichroic azo dye compound having a maximum absorption wavelength in the range of 455 to 555 nm, and more preferably to have a dichroic azo dye compound having a maximum absorption wavelength in the range of 455 to 550 nm.

[0448] In particular, it is easier to adjust the hue of the polarizer by using a first dichroic azo dye compound with a maximum absorption wavelength of 560–700 nm and a second dichroic azo dye compound with a maximum absorption wavelength of 455 nm or more but less than 560 nm.

[0449] From the perspective of further improving the orientation degree of the polarizer, the second dichroic azo dye compound is preferably the compound represented by formula (2).

[0450] [Chemical Formula 28]

[0451]

[0452] In equation (2), n represents 1 or 2.

[0453] In formula (2), Ar3, Ar4 and Ar5 independently represent phenylene, naphthylene, or heterocyclic group that can have substituents, respectively.

[0454] As a heterocyclic group, it can be either aromatic or non-aromatic.

[0455] Examples of atoms other than carbon that constitute aromatic heterocyclic groups include nitrogen, sulfur, and oxygen atoms. In the case of aromatic heterocyclic groups having multiple atoms constituting the rings other than carbon, these atoms can be the same or different.

[0456] Specific examples of aromatic heterocyclic groups include pyridinyl (pyridine-diyl), pyridazine-diyl, imidazole-diyl, thiophene (thiophene-diyl), quinolineyl (quinoline-diyl), isoquinolineyl (isoquinoline-diyl), oxazole-diyl, thiazole-diyl, oxadiazole-diyl, benzothiazole-diyl, benzothiadiazole-diyl, phthalimide-diyl, thienothiazole-diyl, thiazonothiazole-diyl, thienothiphene-diyl, and thienooxazole-diyl.

[0457] In equation (2), R4 is defined in the same way as R1 in equation (1).

[0458] In equation (2), the definitions of R5 and R6 are the same as those of R2 and R3 in equation (1).

[0459] From the viewpoint of lightfastness, R4 is preferably an electron-withdrawing group, and R5 and R6 are preferably groups with low electron-donating properties.

[0460] In this group, the specific examples of R4 being an electron-withdrawing group are the same as those of R1 being an electron-withdrawing group, and the specific examples of R5 and R6 being groups with low electron-donating properties are the same as those of R2 and R3 being groups with low electron-donating properties.

[0461] The following are specific examples of second dichroic azo dye compounds, but are not limited to them.

[0462] [Chemical Formula 29]

[0463]

[0464]

[0465]

[0466]

[0467] (Difference in logP values)

[0468] The logP value is an indicator of the hydrophilicity and hydrophobicity of the chemical structure. The absolute value of the difference between the logP value of the side chain of the first dichroic azo dye compound and the logP value of the side chain of the second dichroic azo dye compound (hereinafter also referred to as "logP difference") is preferably 2.30 or less, more preferably 2.0 or less, even more preferably 1.5 or less, and particularly preferably 1.0 or less. If the logP difference is 2.30 or less, the affinity between the first dichroic azo dye compound and the second dichroic azo dye compound is increased, making it easier to form an alignment structure, and thus the orientation degree of the light-absorbing anisotropic layer is further improved.

[0469] Furthermore, when there are multiple side chains of the first or second dichroic azo dye compound, it is preferable that at least one logP difference satisfies the above value.

[0470] Here, the side chains of the first and second dichroic azo pigment compounds refer to the groups bonded to the ends of the chromophores. For example, when the first dichroic azo pigment compound is a compound represented by formula (1), R1, R2, and R3 in formula (1) are side chains, and when the second dichroic azo pigment compound is a compound represented by formula (2), R4, R5, and R6 in formula (2) are side chains. In particular, when the first dichroic azo pigment compound is a compound represented by formula (1) and the second dichroic azo pigment compound is a compound represented by formula (2), it is preferable that at least one logP difference among the differences in logP values ​​of R1 and R4, R1 and R5, R2 and R4, and R2 and R5 satisfies the above-mentioned value.

[0471] 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 logP value is the value calculated by inputting the structural formula of the compound into HSPiP (Ver. 4.1.07).

[0472] (Third dichroic azo pigment compound)

[0473] The third dichroic azo pigment compound is a dichroic azo pigment compound other than the first and second dichroic azo pigment compounds. Specifically, its chemical structure differs from that of the first and second dichroic azo pigment compounds. If the composition for forming the light absorption anisotropic layer contains the third dichroic azo pigment compound, it has the advantage of easily adjusting the hue of the light absorption anisotropic layer.

[0474] The maximum absorption wavelength of the third dichroic azo dye compound is above 380 nm and below 455 nm, preferably 385 to 454 nm.

[0475] The third dichroic azo dye compound preferably contains a dichroic azo dye represented by the following formula (6).

[0476] [Chemical Formula 30]

[0477]

[0478] In equation (6), A and B represent crosslinking groups independently.

[0479] In equation (6), a and b represent 0 or 1 independently, respectively. For excellent orientation at 420 nm, it is preferable that both a and b are 0.

[0480] In equation (6), 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.

[0481] In formula (6), 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).

[0482] In equation (6), R1, R2, and R3 each independently represent a monovalent substituent. When n1≥2, multiple R1s can be the same or different; when n2≥2, multiple R2s can be the same or different; and when n3≥2, multiple R3s can be the same or different.

[0483] In equation (6), 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.

[0484] In equation (6), n1, n2, and n3 independently represent integers from 0 to 4. However, when k = 1, n1 + n2 + n3 ≥ 0, and when k ≥ 2, n1 + n2 + n3 ≥ 1.

[0485] In formula (6), the crosslinking groups represented by A and B can be exemplified by polymerizable groups described in paragraphs

[0040] to

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

[0486] In equation (6), 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.

[0487] The monovalent substituents represented by L1 and L2 are preferably groups introduced to improve the solubility of dichroic substances or groups with electron-donating or electron-withdrawing properties introduced to adjust the hue of pigments.

[0488] For example, as a substituent, it can be used

[0489] Alkyl group (preferably with 1 to 20 carbon atoms, more preferably with 1 to 12 carbon atoms, and especially preferably with 1 to 8 carbon atoms, such as methyl, ethyl, isopropyl, tert-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, etc.)

[0490] Alkenyl (preferably with 2 to 20 carbon atoms, more preferably with 2 to 12 carbon atoms, and especially preferably with 2 to 8 carbon atoms, such as vinyl, allyl, 2-butenyl, 3-pentenyl, etc.)

[0491] Alkynyl (preferably with 2 to 20 carbon atoms, more preferably with 2 to 12 carbon atoms, and especially preferably with 2 to 8 carbon atoms, such as propynyl, 3-pentynyl, etc.)

[0492] Aryl groups (preferably with 6 to 30 carbon atoms, more preferably with 6 to 20 carbon atoms, and especially preferably with 6 to 12 carbon atoms, such as phenyl, 2,6-diethylphenyl, 3,5-ditrifluoromethylphenyl, naphthyl, and biphenyl, etc.)

[0493] Substituted or unsubstituted amino groups (preferably with 0 to 20 carbon atoms, more preferably with 0 to 10 carbon atoms, and especially preferably with 0 to 6 carbon atoms, such as unsubstituted amino groups, methylamino groups, dimethylamino groups, diethylamino groups, aniline groups, etc.)

[0494] Alkyl groups (preferably with 1 to 20 carbon atoms, more preferably with 1 to 15 carbon atoms, for example, methoxy, ethoxy, butoxy, etc.)

[0495] Oxycarbonyl (preferably with 2 to 20 carbon atoms, more preferably with 2 to 15 carbon atoms, especially preferably with 2 to 10 carbon atoms, for example, methoxycarbonyl, ethoxycarbonyl, phenoxycarbonyl, etc.), acyloxy (preferably with 2 to 20 carbon atoms, more preferably with 2 to 10 carbon atoms, especially preferably with 2 to 6 carbon atoms, for example, acetoxy and benzoyloxy, etc.)

[0496] Acylamino group (preferably with 2 to 20 carbon atoms, more preferably with 2 to 10 carbon atoms, and especially preferably with 2 to 6 carbon atoms, such as acetamino and benzoylamino groups, etc.)

[0497] Alkoxycarbonylamino (preferably with 2 to 20 carbon atoms, more preferably with 2 to 10 carbon atoms, and especially preferably with 2 to 6 carbon atoms, such as methoxycarbonylamino, etc.)

[0498] Aryloxycarbonylamino (preferably with 7 to 20 carbon atoms, more preferably with 7 to 16 carbon atoms, and especially preferably with 7 to 12 carbon atoms, such as phenoxycarbonylamino, etc.)

[0499] Sulfonamide (preferably with 1 to 20 carbon atoms, more preferably with 1 to 10 carbon atoms, and especially preferably with 1 to 6 carbon atoms, for example, methanesulfonamide, benzenesulfonamide, etc.)

[0500] Aminosulfonyl group (preferably with 0 to 20 carbon atoms, more preferably with 0 to 10 carbon atoms, and especially preferably with 0 to 6 carbon atoms, for example, aminosulfonyl, methylaminosulfonyl, dimethylaminosulfonyl, phenylaminosulfonyl, etc.)

[0501] Carbamoyl group (preferably with 1 to 20 carbon atoms, more preferably with 1 to 10 carbon atoms, and especially preferably with 1 to 6 carbon atoms, for example, unsubstituted carbamoyl group, methyl carbamoyl group, diethyl carbamoyl group, phenyl carbamoyl group, etc.)

[0502] Alkylthio (preferably with 1 to 20 carbon atoms, more preferably with 1 to 10 carbon atoms, and especially preferably with 1 to 6 carbon atoms, for example, methylthio, ethylthio, etc.)

[0503] Arylthioyl group (preferably with 6 to 20 carbon atoms, more preferably with 6 to 16 carbon atoms, especially preferably with 6 to 12 carbon atoms, for example, phenylthioyl group, etc.),

[0504] Sulfonyl group (preferably with 1 to 20 carbon atoms, more preferably with 1 to 10 carbon atoms, and especially preferably with 1 to 6 carbon atoms, for example, methanesulfonyl group, toluenesulfonyl group, etc.)

[0505] Thionyl group (preferably with 1 to 20 carbon atoms, more preferably with 1 to 10 carbon atoms, and especially preferably with 1 to 6 carbon atoms, for example, methanethionyl group, phenylthionyl group, etc.)

[0506] Urea group (preferably with 1 to 20 carbon atoms, more preferably with 1 to 10 carbon atoms, especially preferably with 1 to 6 carbon atoms, such as unsubstituted urea group, methylurea group, phenylurea group, etc.), phosphoramide group (preferably with 1 to 20 carbon atoms, more preferably with 1 to 10 carbon atoms, especially preferably with 1 to 6 carbon atoms, such as diethylphosphoramide group, phenylphosphoramide group, etc.),

[0507] Heterocyclic groups (preferably heterocyclic groups with 1 to 30 carbon atoms, more preferably 1 to 12, such as heterocyclic groups with heteroatoms such as nitrogen atom, oxygen atom, sulfur atom, etc., examples include imidazole group, pyridinyl group, quinolinyl group, furanyl group, piperidinyl group, morpholinyl group, benzoxazolyl group, benzimidazolyl group, benzothiazolyl group, etc.)

[0508] Silicyl groups (preferably silanes with 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, and especially preferably silanes with 3 to 24 carbon atoms, such as trimethylsilanes and triphenylsilanes),

[0509] Halogen atoms (e.g., fluorine, chlorine, bromine, iodine),

[0510] Hydroxyl, mercapto, cyano, nitro, oxime, sulfinyl, hydrazine, imino, and azo groups, etc.

[0511] These substituents can also be substituted by other substituents. Furthermore, when there are two or more substituents, they can be the same or different. And, where possible, they can bond together to form a ring.

[0512] As a group in which the above-mentioned substituents are further replaced by the above-mentioned substituents, examples include groups in which the alkoxy group is replaced by an alkyl group, i.e., R. B -(OR A ) na -Base. Here, in the formula, R A R represents an alkylene group having 1 to 5 carbon atoms. B The alkyl group represents 1 to 5 carbon atoms, and na represents an integer from 1 to 10 (preferably 1 to 5, more preferably 1 to 3).

[0513] Among them, the substituents with a monovalent valence represented by L1 and L2 are preferably alkyl, alkenyl, alkoxy, and groups in which these groups are further substituted (e.g., R as described above). B -(OR A ) na - group), more preferably alkyl, alkoxy, and groups further substituted by these groups (e.g., R group described above). B -(OR A ) na -base).

[0514] Examples of divalent linker bases represented by L1 and L2 include -O-, -S-, -CO-, -COO-, -OCO-, -O-CO-O-, and -CO-NR. N -、-O-CO-NR N -、-NR N -CO-NR N-, -SO2-, -SO-, alkylene, cycloalkylene and alkenylene groups, and groups composed of two or more of these groups.

[0515] Among them, the preferred combination is a group consisting of an alkylene group and one or more groups selected from the group consisting of -O-, -COO-, -OCO- and -O-CO-O-.

[0516] Here, R N Represents a hydrogen atom or an alkyl group. In the presence of multiple R... N In the case of multiple R N They can be the same or different.

[0517] From the viewpoint of further improving the solubility of dichroic substances, the number of atoms in at least one main chain of L1 and L2 is preferably 3 or more, more preferably 5 or more, even more preferably 7 or more, and particularly preferably 10 or more. Furthermore, the upper limit of the number of atoms in the main chain is preferably 20 or less, more preferably 12 or less.

[0518] On the other hand, from the viewpoint of further improving the orientation degree of the light absorption anisotropy layer, the number of atoms in at least one main chain of L1 and L2 is preferably 1 to 5.

[0519] Here, when A is present in equation (6), the "main chain" in L1 refers to the portion required to directly connect the "O" atom and "A" connected to L1, and the "number of atoms in the main chain" refers to the number of atoms constituting the aforementioned portion. Similarly, when B is present in equation (6), the "main chain" in L2 refers to the portion required to directly connect the "O" atom and "B" connected to L2, and the "number of atoms in the main chain" refers to the number of atoms constituting the aforementioned portion. In addition, the "number of atoms in the main chain" does not include the number of atoms in the side chains, which will be described later.

[0520] Furthermore, in the absence of A, the "number of atoms in the main chain" in L1 refers to the number of atoms in L1 that do not contain branches. In the absence of B, the "number of atoms in the main chain" in L2 refers to the number of atoms in L2 that do not contain branches.

[0521] Specifically, in equation (D1) below, the main chain of L1 has 5 atoms (the number of atoms in the dotted box on the left side of equation (D1) below), and the main chain of L2 has 5 atoms (the number of atoms in the dotted box on the right side of equation (D1) below). Furthermore, in equation (D10) below, the main chain of L1 has 7 atoms (the number of atoms in the dotted box on the left side of equation (D10) below), and the main chain of L2 has 5 atoms (the number of atoms in the dotted box on the right side of equation (D10) below).

[0522] [Chemical Formula 31]

[0523]

[0524] L1 and L2 can have branches.

[0525] Here, when A is present in equation (6), the “branch” in L1 refers to the portion other than that required for directly connecting the “O” atom and “A” connected to L1 in equation (6). Similarly, when B is present in equation (6), the “branch” in L2 refers to the portion other than that required for directly connecting the “O” atom and “B” connected to L2 in equation (6).

[0526] Furthermore, in the absence of A in equation (6), the “branch” in L1 refers to the portion other than the longest atomic chain (i.e., the main chain) extending from the “O” atom connected to L1 in equation (6). Similarly, in the absence of B in equation (6), the “branch” in L2 refers to the portion other than the longest atomic chain (i.e., the main chain) extending from the “O” atom connected to L2 in equation (6).

[0527] The number of atoms in the branched chain is preferably three or less. Having three or fewer atoms in the branched chain has advantages such as further improving the orientation degree of the light-absorbing anisotropic layer. Furthermore, the number of atoms in the branched chain does not include hydrogen atoms.

[0528] In formula (6), Ar1 represents an aromatic hydrocarbon group or heterocyclic group with a valence of (n1+2) (e.g., trivalent when n1 is 1), Ar2 represents an aromatic hydrocarbon group or heterocyclic group with a valence of (n2+2) (e.g., trivalent when n2 is 1), and Ar3 represents an aromatic hydrocarbon group or heterocyclic group with a valence of (n3+2) (e.g., trivalent when n3 is 1). Here, Ar1 to Ar3 can be expressed in other words as divalent aromatic hydrocarbon groups or divalent heterocyclic groups substituted by n1 to n3 substituents (R1 to R3 described later).

[0529] The divalent aromatic hydrocarbon group represented by Ar1 to Ar3 can be a monocyclic ring or a fused ring structure with more than two rings. From the viewpoint of further improving solubility, the number of rings in the divalent aromatic hydrocarbon group is preferably 1 to 4, more preferably 1 to 2, and even more preferably 1 (i.e., phenylene).

[0530] Specific examples of divalent aromatic hydrocarbon groups include phenylene, azyl-diyl, naphthylene, fluorene-diyl, anthracene-diyl, and tetraphenyl-diyl. From the viewpoint of further improving solubility, phenylene and naphthylene are preferred, and phenylene is more preferred.

[0531] The following are specific examples of third dichroic compounds, but the present invention is not limited thereto. Furthermore, in the following specific examples, n represents an integer from 1 to 10.

[0532] [Chemical Formula 32]

[0533]

[0534] [Chemical Formula 33]

[0535]

[0536] In terms of excellent orientation at 420 nm, it is preferable that the third pigment does not have a structure with free radical polymerizable groups. For example, the following structures can be cited.

[0537] [Chemical Formula 34]

[0538]

[0539] In terms of particularly excellent orientation at 420 nm, the third dichroic azo dye compound is more preferably a dichroic substance having a structure represented by the following formula (1-1).

[0540] [Chemical Formula 35]

[0541]

[0542] In equation (1-1), the definitions of R1, R3, R4, R5, n1, n3, L1 and L2 are the same as the definitions of R1, R4, R5, n1, n3, L1 and L2 in equation (1).

[0543] In equation (1-1), R 21 and R 22 The definitions of are independently the same as the definition of R2 in equation (1).

[0544] In equation (1-1), the definitions of n21 and n22 are independently the same as the definition of n2 in equation (1).

[0545] n1+n21+n22+n3≥1, n1+n21+n22+n3 is preferably 1~9, and more preferably 1~5.

[0546] The following are specific examples of dichroic substances, but the present invention is not limited to these.

[0547] [Chemical Formula 36]

[0548]

[0549] [Chemical Formula 37]

[0550]

[0551] [Chemical Formula 38]

[0552]

[0553] (Content of dichroic substances)

[0554] The content of the dichroic substance relative to the total solid content of the light-absorbing anisotropic layer is preferably 5-30% by mass, more preferably 15-28% by mass, and even more preferably 20-30% by mass. If the content of the dichroic substance is within the above range, a light-absorbing anisotropic layer with high orientation can be obtained even when the light-absorbing anisotropic layer is a thin film. Therefore, a light-absorbing anisotropic layer with excellent flexibility is easily obtained. Furthermore, if it exceeds 30% by mass, it becomes difficult to suppress internal reflection by increasing the refractive index.

[0555] From the perspective of improving the contrast between illuminance at the center of the viewing angle and illuminance in directions away from the center of the viewing angle, the preferred content of the dichroic substance per unit area is 0.2 g / m². 2 The above, more preferably 0.3 g / m 2 The above, more preferably 0.5 g / m 2 That's all. There's no specific upper limit, but it's usually around 1.0 g / m³. 2 Used below.

[0556] The content of the first dichroic azo dye compound is 100 parts by mass relative to the total content of the dichroic substance in the composition for forming anisotropic light absorption layers, preferably 40 to 90 parts by mass, more preferably 45 to 75 parts by mass.

[0557] The content of the second dichroic azo dye compound is preferably 6 to 50 parts by mass relative to the total content of the dichroic substance in the composition for forming the light-absorbing anisotropic layer, more preferably 8 to 35 parts by mass.

[0558] The content of the third dichroic azo dye compound is preferably 3 to 35 parts by mass relative to 100 parts by mass of the dichroic azo dye compound in the composition for forming anisotropic light absorption layers, more preferably 5 to 30 parts by mass.

[0559] To adjust the hue of the light absorption anisotropic layer, the content ratios of the first dichroic azo dye compound, the second dichroic azo dye compound, and the third dichroic azo dye compound (if used as needed) can be arbitrarily set. However, the content ratio of the second dichroic azo dye compound to the first dichroic azo dye compound (second dichroic azo dye compound / first dichroic azo dye compound) is preferably 0.1 to 10 in molar terms, more preferably 0.2 to 5, and particularly preferably 0.3 to 0.8. If the content ratio of the second dichroic azo dye compound to the first dichroic azo dye compound is within the above range, the orientation degree can be improved.

[0560] The light-absorbing anisotropic layer of the present invention can be formed, for example, using a light-absorbing anisotropic layer forming composition containing the above-mentioned organic dichroic substance.

[0561] The composition for forming a light-absorbing anisotropic layer may contain components other than organic dichroic substances, such as liquid crystal compounds, solvents, vertical alignment agents, polymerizable components, polymerization initiators (e.g., free radical polymerization initiators), and leveling agents. In this case, the light-absorbing anisotropic layer of the present invention contains solid components other than liquid components (solvents, etc.).

[0562] Furthermore, the first orientation layer in this invention can be formed in the same way as the light absorption anisotropic layer using a composition obtained by removing dichroic substances from a composition for forming a light absorption anisotropic layer.

[0563] (polymeric components)

[0564] Examples of polymerizable components include compounds containing acrylates (e.g., acrylate monomers). In this case, the light-absorbing anisotropic layer of the present invention contains a polyacrylate obtained by polymerizing a compound containing the aforementioned acrylate.

[0565] Examples of polymerizable components include, for instance, the compounds described in paragraph 0058 of Japanese Patent Application Publication No. 2017-122776.

[0566] When the composition for forming anisotropic light-absorbing layers contains a polymerizable component, the content of the polymerizable component is preferably 3 to 20 parts by mass relative to the total of 100 parts by mass of the organic dichroic substance and the liquid crystal compound in the composition for forming anisotropic light-absorbing layers.

[0567] (Vertical Orientation Agent)

[0568] In this invention, a vertical alignment agent may also be included as needed. Examples of vertical alignment agents include boric acid compounds and onium salts.

[0569] As a boric acid compound, the compound represented by formula (30) is preferred.

[0570] Equation (30)

[0571] [Chemical Formula 39]

[0572]

[0573] In equation (30), R 1 and R 2 Each of these groups independently represents a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group.

[0574] R3 indicates a substituent containing a (meth)acryloyl group.

[0575] As a specific example of boric acid compounds, one can cite the boric acid compounds represented by general formula (I) described in paragraphs 0023 to 0032 of Japanese Patent Application Publication No. 2008-225281.

[0576] The following compounds are also preferred as boric acid compounds.

[0577] [Chemical Formula 40]

[0578]

[0579] As a ium salt, the compound represented by formula (31) is preferred.

[0580] Equation (31)

[0581] [Chemical Formula 41]

[0582]

[0583] In formula (31), ring A represents a quaternary ammonium ion composed of a nitrogen-containing heterocycle. X represents an anion. L 1 This represents a binary linker. L 2 Represents a single bond or a divalent linker. Y 1 The symbol "Z" indicates a divalent linker with a 5- or 6-membered ring as part of the structure. The symbol "P" indicates a divalent linker with 2–20 alkylene groups as part of the structure. 1 and P 2 Each of these represents a monovalent substituent that has a polymerizable alkene unsaturated bond.

[0584] Specific examples of onium salts include those described in paragraphs 0052 to 0058 of Japanese Patent Application Publication No. 2012-208397, those described in paragraphs 0024 to 0055 of Japanese Patent Application Publication No. 2008-026730, and those described in Japanese Patent Application Publication No. 2002-37777.

[0585] The content of the vertical alignment agent in the composition is preferably 0.1 to 400% by mass relative to the total mass of the liquid crystal compound, more preferably 0.5 to 350% by mass.

[0586] Vertical alignment agents can be used alone or in combination of two or more. When using two or more vertical alignment agents, it is preferable that their combined dosage is within the range described above.

[0587] (Leveling agent)

[0588] Preferably, the composition contains the following leveling agent. If the composition contains a leveling agent, it can suppress the roughness of the surface caused by the drying wind applied to the surface of the light-absorbing anisotropic layer, and the dichroic material can be more uniformly oriented in the light-absorbing anisotropic layer.

[0589] Leveling agents can also be used as so-called surfactants.

[0590] There are no particular restrictions on leveling agents, but leveling agents containing fluorine atoms (fluorine-based leveling agents) or leveling agents containing silicon atoms (silicone-based leveling agents) are preferred, and fluorine-based leveling agents are even more preferred.

[0591] Examples of fluorinated leveling agents include fatty acid esters of polycarboxylic acids in which a portion of the fatty acid is replaced by a fluorinated alkyl group, and polyacrylates having fluorinated substituents. In particular, when rod-shaped compounds are used as dichroic substances and liquid crystal compounds, leveling agents containing repeating units of compounds derived from free formula (40) are preferred from the perspective of promoting the vertical orientation of dichroic substances and liquid crystal compounds.

[0592] Equation (40)

[0593] [Chemical Formula 42]

[0594]

[0595] R 0 It represents a hydrogen atom, a halogen atom, or a methyl group.

[0596] L represents a divalent linker. Preferably, L is an alkylene group with 2 to 16 carbon atoms, and any non-adjacent -CH2- in the alkylene group can be replaced by -O-, -COO-, -CO- or -CONH-.

[0597] n represents an integer from 1 to 18.

[0598] Leveling agents having repeating units of compounds represented by formula (40) may also contain other repeating units.

[0599] Other repeating units can be cited from the repeating units of compounds represented by free formula (41).

[0600] Equation (41)

[0601] [Chemical Formula 43]

[0602]

[0603] R 11 It represents a hydrogen atom, a halogen atom, or a methyl group.

[0604] X represents an oxygen atom, a sulfur atom, or -N(R) 13 )-. R 13It represents an alkyl group having 1 to 8 hydrogen atoms or carbon atoms.

[0605] R 12 The alkyl group represents a hydrogen atom, an alkyl group that may have substituents, or an aromatic group that may have substituents. The alkyl group preferably has 1 to 20 carbon atoms. The alkyl group can be linear, branched, or cyclic.

[0606] Furthermore, examples of substituents that can have the aforementioned alkyl groups include poly(alkoxide) groups and polymerizable groups. The definition of polymerizable groups is as described above.

[0607] When the leveling agent contains repeating units of a compound represented by formula (40) and repeating units of a compound represented by formula (41), the content of repeating units of the compound represented by formula (40) is preferably 10 to 90 mol% relative to the total repeating units contained in the leveling agent, more preferably 15 to 95 mol%.

[0608] When the leveling agent contains repeating units of a compound represented by formula (40) and repeating units of a compound represented by formula (41), the content of repeating units of the compound represented by formula (41) is preferably 10 to 90 mol% relative to the total repeating units contained in the leveling agent, more preferably 5 to 85 mol%.

[0609] Furthermore, as a leveling agent, one can also cite a leveling agent in which the repeating unit of the compound represented by formula (40) above is contained in the repeating unit of the compound represented by formula (42).

[0610] Equation (42)

[0611] [Chemical Formula 44]

[0612]

[0613] R 2 It represents a hydrogen atom, a halogen atom, or a methyl group.

[0614] L 2 This indicates a divalent linker.

[0615] n represents an integer from 1 to 18.

[0616] Specific examples of leveling agents include the compounds illustrated in paragraphs 0046 to 0052 of Japanese Patent Application Publication No. 2004-331812 and the compounds described in paragraphs 0038 to 0052 of Japanese Patent Application Publication No. 2008-257205.

[0617] The leveling agent content in the composition is preferably 0.001 to 10% by mass relative to the total mass of the liquid crystal compound, more preferably 0.01 to 5% by mass.

[0618] Leveling agents can be used alone or in combination of two or more. When using two or more leveling agents, it is preferable that their combined dosage is within the range mentioned above.

[0619] (Polymerization initiator)

[0620] The composition for forming anisotropic light-absorbing layers preferably contains a polymerization initiator.

[0621] There are no particular limitations on the polymerization initiator, but photosensitive compounds, i.e., photopolymerization initiators, are preferred.

[0622] As photopolymerization initiators, a wide variety of compounds can be used without particular limitation. 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). (e.g., acridine and phenazine compounds (Japanese Patent Application Publication No. 60-105667, 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.

[0623] 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.

[0624] When the composition for forming anisotropic light-absorbing layers contains a polymerization initiator, the content of the polymerization initiator is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 15 parts by mass, relative to the total of 100 parts by mass of the dichroic substance and the polymeric liquid crystal compound in the composition for forming anisotropic light-absorbing layers. When the content of the polymerization initiator is 0.01 parts by mass or more, the durability of the anisotropic light-absorbing film becomes better; when it is 30 parts by mass or less, the orientation degree of the anisotropic light-absorbing film becomes better.

[0625] A single polymerization initiator may be used, or two or more may be used in combination. When two or more polymerization initiators are used, it is preferable that their total amount is within the range described above.

[0626] (solvent)

[0627] From the viewpoint of operability, the composition for forming anisotropic light-absorbing layers used in this invention preferably contains a solvent.

[0628] Examples of solvents include ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, etc.), ethers (e.g., dioxane, tetrahydrofuran, 2-methyltetrahydrofuran, cyclopentylmethyl ether, tetrahydropyran, dioxolane, etc.), aliphatic hydrocarbons (e.g., hexane, etc.), alicyclic hydrocarbons (e.g., cyclohexane, etc.), aromatic hydrocarbons (e.g., benzene, toluene, xylene, trimethylbenzene, etc.), carbon halogens (e.g., dichloromethane, trichloromethane, dichloroethane, dichlorobenzene, chlorotoluene, etc.), and esters (e.g., methyl acetate, ethyl acetate, acetic acid). Organic solvents such as butyl acetate, ethyl lactate, etc., alcohols (e.g., ethanol, isopropanol, butanol, cyclohexanol, isoamyl alcohol, n-pentanol, diacetone alcohol, benzyl alcohol, etc.), cellosols (e.g., methyl cellosol, ethyl cellosol, 1,2-dimethoxyethane, etc.), cellosol acetates, sulfoxides (e.g., dimethyl sulfoxide, etc.), amides (e.g., dimethylformamide, dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone, 1,3-dimethyl-2-imidazolium ketone, etc.), and heterocyclic compounds (e.g., pyridine, N-methylimidazole, etc.) and water can be used. These solvents can be used individually or in combination of two or more.

[0629] Among these solvents, from the viewpoint of achieving excellent solubility, ketones (especially cyclopentanone and cyclohexanone), ethers (especially tetrahydrofuran, cyclopentylmethyl ether, tetrahydropyran, and dioxolane), and amides (especially dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and N-ethylpyrrolidone) are preferred.

[0630] When the composition for forming anisotropic light-absorbing layers contains a solvent, the solvent content relative to the total mass of the composition for forming anisotropic light-absorbing layers is preferably 80 to 99% by mass, more preferably 83 to 97% by mass, and particularly preferably 85 to 95% by mass.

[0631] A single solvent may be used, or two or more solvents may be used in combination. When two or more solvents are used, it is preferable that their total amount is within the range described above.

[0632] The light-absorbing anisotropic thin film of the present invention may have only a light-absorbing anisotropic layer and a first orientation layer, but may also be a laminate having other layers as needed.

[0633] For example, the light-absorbing anisotropic thin film of the present invention is as described above. Figure 2 As shown, in addition to the light-absorbing anisotropic layer 2 and the first orientation layer 3, the second orientation layer is preferably provided, as well as the blocking layer 1 and the TAC film 5.

[0634] [Support]

[0635] The light-absorbing anisotropic thin film of the present invention can have a support for supporting the light-absorbing anisotropic thin film. Figure 2 In the light-absorbing anisotropic thin film 101 shown, the TAC film 5 serves as the support.

[0636] The support is preferably positioned on the surface opposite to the air layer. Furthermore, in the case where the anisotropic absorption film has a protective layer for protecting the light-absorbing anisotropic layer, the support is preferably positioned on the surface opposite to the surface where the protective layer is provided.

[0637] As a support, known transparent resin films, transparent resin sheets, transparent resin plates, etc., can be used, but there are no particular limitations. As a transparent resin film, cellulose acylate films (e.g., cellulose triacetate films (refractive index 1.48), cellulose diacetate films, cellulose acetate butyrate films, cellulose acetate propionate films), polyethylene terephthalate films, polyethersulfone films, polyacrylic acid resin films, polyurethane resin films, polyester films, polycarbonate films, polysulfone films, polyether films, polymethylpentene films, polyetherketone films, (meth)acrylonitrile films, etc., can be used.

[0638] Among them, cellulose acylate films, which are commonly used as protective films for polarizers, are preferred due to their high transparency, low optical birefringence, and ease of manufacture. Cellulose triacetate films are particularly preferred.

[0639] The thickness of the support is typically 20μm to 100μm.

[0640] In this invention, the support is particularly preferred to be a cellulose ester film with a thickness of 20 to 70 μm.

[0641] [Protective Layer]

[0642] The light-absorbing anisotropic thin film of the present invention preferably has a protective layer for protecting the light-absorbing anisotropic layer. As a protective layer, various known layers (films) can be used as long as they can protect the light-absorbing anisotropic layer, but a blocking layer is preferred.

[0643] Figure 2 The light-absorbing anisotropic thin film shown has a blocking layer 1 on the surface of the light-absorbing anisotropic layer 2 (on the side opposite to the support).

[0644] The barrier layer, also known as the gas barrier layer (oxygen barrier layer), has the function of protecting the polarization element of the present invention from gases such as oxygen in the atmosphere, moisture, or compounds contained in adjacent layers.

[0645] Regarding the barrier layer, for example, reference can be made to paragraphs

[0014] to

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

[0042] to

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

[0045] to

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

[0010] to

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

[0021] to

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

[0646] [Refractive index adjustment layer]

[0647] In the laminate of the present invention, the light-absorbing anisotropic layer has a dichroic material, and sometimes internal reflection caused by the high refractive index of the light-absorbing anisotropic layer becomes a problem.

[0648] In this case, a refractive index adjustment layer is preferred. The refractive index adjustment layer is a layer configured to be in contact with the light-absorbing anisotropic layer, and has an in-plane average refractive index of 1.55 or higher and 1.70 or lower at a wavelength of 550 nm. Preferably, it is a refractive index adjustment layer used for so-called refractive index matching.

[0649] <Other Layers>

[0650] In addition to the layers described above, the light-absorbing anisotropic thin film of the present invention may also have, as needed, layers (thin films, membranes) such as phase retardation layers, anti-reflection layers, and various thin films, exhibiting various functions.

[0651] Furthermore, the light-absorbing anisotropic thin film of the present invention is not limited to, for example, the following: Figure 2 The structure shown can utilize various layer structures as long as it has an anisotropic light absorption layer.

[0652] For example, the light-absorbing anisotropic thin film of the present invention may have only a light-absorbing anisotropic layer and a first orientation layer, or it may be composed only of a light-absorbing anisotropic layer, a first orientation layer and a second orientation layer, or it may be composed of a light-absorbing anisotropic layer, a first orientation layer and a blocking layer.

[0653] <Methods for forming anisotropic light-absorbing layers>

[0654] There is no particular limitation on the method for forming the light-absorbing anisotropic layer. A method that includes the following steps in sequence is: a step of coating the above-mentioned light-absorbing anisotropic layer forming composition to form a coating film (hereinafter also referred to as the "coating film forming step"); and a step of orienting the liquid crystal compound and dichroic substance contained in the coating film (hereinafter also referred to as the "orientation step").

[0655] In addition, liquid crystal components refer to components that not only contain the aforementioned liquid crystal compounds, but also, in the case where the aforementioned organic dichroic substances possess liquid crystal properties, contain organic dichroic substances that also possess liquid crystal properties.

[0656] Furthermore, as described above, the first orientation layer can be formed in the same way as the light absorption anisotropic layer using a composition obtained by removing organic dichroic substances from a composition for forming a light absorption anisotropic layer.

[0657] (Coating film formation process)

[0658] The coating film formation process is a process of forming a coating film by coating a light-absorbing anisotropic layer composition.

[0659] The light-absorbing anisotropic layer forming composition can be easily coated by using a composition containing the above-mentioned solvent or by using a liquid such as a melt prepared from the light-absorbing anisotropic layer forming composition by heating.

[0660] The coating method for the composition for forming anisotropic light-absorbing layers includes, for example, 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.

[0661] (Orientation process)

[0662] The alignment process is a process that orients the liquid crystal components contained in the coated film. As a result, an anisotropic light absorption layer can be obtained.

[0663] 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.

[0664] Here, the liquid crystal components contained in the composition for forming anisotropic light absorption layers are sometimes oriented through the above-described coating film forming process or drying process. For example, in the method of preparing a coating liquid containing a solvent from the composition for forming anisotropic light absorption layers, a coating film with anisotropic light absorption (i.e., anisotropic light absorption film) can be obtained by drying the coating film to remove the solvent from the coating film.

[0665] If the drying process is performed 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 necessary.

[0666] 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, cooling treatment to lower the temperature to the liquid crystal phase temperature range is not required, which is therefore preferable. Furthermore, if the transition temperature is 250°C or lower, even when the liquid crystal component is made into an isotropic liquid state at a temperature higher than the temporary liquid crystal phase temperature range, high temperature is not required, which can reduce heat waste and substrate deformation and deterioration, and is therefore preferable.

[0667] 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.

[0668] 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.

[0669] 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.

[0670] Through the above processes, anisotropic light absorption films can be obtained.

[0671] Furthermore, in the above description, the methods for aligning the liquid crystal components contained in the coating film include drying treatment and heat treatment, but the alignment process is not limited to these, and known alignment treatments can be used.

[0672] (Other processes)

[0673] The method for forming a light-absorbing anisotropic layer may include a step (hereinafter also referred to as the "curing step") after the above-mentioned orientation step to cure the light-absorbing anisotropic layer.

[0674] For example, when the light-absorbing anisotropic layer has cross-linking groups (polymeric groups), the curing process is carried out by heating and / or light irradiation (exposure). Preferably, the curing process is carried out by light irradiation.

[0675] The light used for curing can be various types of light (electromagnetic waves) such as infrared, visible light, and ultraviolet light, but ultraviolet light is preferred. This light can be emitted using a light source that emits light of a specific wavelength (wavelength range), or by irradiating the light through a thin film that transmits light of only a specific wavelength (wavelength range).

[0676] Furthermore, during the curing process, heating and ultraviolet light can be applied simultaneously.

[0677] When heating is performed while light is applied, although the heating temperature during light irradiation also depends on the transition temperature of the liquid crystal components contained in the liquid crystal film to the liquid crystal phase, it is preferably 25 to 140°C.

[0678] Furthermore, light irradiation can be performed under a nitrogen atmosphere. Since the curing of the liquid crystal film via free radical polymerization reduces the polymerization hindrance caused by oxygen, it is preferable to perform light irradiation under a nitrogen atmosphere.

[0679] The thickness of the light-absorbing anisotropic layer is not particularly limited, but from the viewpoint of miniaturization and lightweighting, it is preferably 100 to 8000 nm, and more preferably 300 to 5000 nm.

[0680] Patterning of anisotropic light absorption layers

[0681] In the light-absorbing anisotropic thin film of the present invention, the light-absorbing anisotropic layer can be a light-absorbing anisotropic layer having regions A and B in the plane and having different transmittance central axes in each region. By controlling the light-emitting pixels by patterning each pixel of the liquid crystal, it is possible to switch the viewing angle center in a narrow viewing angle.

[0682] Furthermore, the light-absorbing anisotropic layer used in this invention can be a light-absorbing anisotropic layer with different transmittances, having regions C and D in the plane and tilted at 30° from the transmittance center axis along the normal direction within regions C and D in a plane containing the transmittance center axis and the normal direction of the thin film surface. In this case, it is preferable that the transmittance of region C tilted at 30° from the transmittance center axis along the normal direction is 50% or less, and the transmittance of region D tilted at 30° from the transmittance center axis along the normal direction is 80% or more.

[0683] By performing this patterning, viewing angle dependence can be enhanced or reduced in localized areas. This allows highly confidential information to be displayed only in areas with enhanced viewing angle dependence. Furthermore, controlling viewing angle dependence at each display position allows for a design with excellent aesthetics. Moreover, by controlling the luminescent pixels through patterning each pixel of the liquid crystal, switching between narrow and wide viewing angles is possible.

[0684] In the following description, this type of light absorption anisotropic layer with two or more different regions in the plane will be referred to as a "patterned light absorption anisotropic layer".

[0685] [Pattern Formation Method]

[0686] Therefore, there are no limitations on the method for forming a patterned light absorption anisotropic layer with two or more different regions in the plane. For example, various known methods as described in International Publication No. 2019 / 176918 can be used. As examples, methods for forming a pattern by changing the irradiation angle of ultraviolet light irradiating the photo-alignment film, methods for controlling the thickness of the patterned light absorption anisotropic layer in the plane, methods for biasing dichroic material compounds in the patterned light absorption anisotropic layer, and methods for post-processing an optically uniform patterned light absorption anisotropic layer are also mentioned.

[0687] Methods for controlling the thickness of an anisotropic patterned light absorption layer in-plane include photolithography, imprinting, and forming an anisotropic patterned light absorption layer on a substrate with a textured surface.

[0688] As a method to cause the dichroic substance compound in the anisotropic layer to be biased for pattern light absorption, one example is the method of extracting the dichroic substance by solvent impregnation (bleaching).

[0689] Furthermore, as a method for post-processing an anisotropic light-absorbing layer with uniform optical properties, one example is a method of cutting a portion of a flat anisotropic light-absorbing layer by means of laser processing or the like.

[0690] The viewing angle control system of the present invention includes the light-absorbing anisotropic thin film and polarizer of the present invention described above.

[0691] [Polarizer]

[0692] The polarizer used in the viewing angle control system of the present invention is not particularly limited as long as it is a component that has the function of converting light into specific linearly polarized light, and conventionally known polarizers can be used.

[0693] As a polarizer, iodine-based polarizers, dye-based polarizers that utilize dichroic dyes, and polyene-based polarizers can be used.

[0694] Iodine-based and dye-based polarizers include both coating-type and stretching-type polarizers, both of which are applicable. As a coating-type polarizer, a polarizer that orients dichroic organic pigments by utilizing the orientation of liquid crystal compounds is preferred. As a stretching-type polarizer, a polarizer made by adsorbing iodine or dichroic dyes onto polyvinyl alcohol and then stretching it is preferred.

[0695] 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. 5048120, Japanese Patent No. 4691205, Japanese Patent No. 4751481, and Japanese Patent No. 4751486, and known technologies related to these polarizers can be preferred.

[0696] In terms of ease of acquisition and excellent polarization, a polarizer comprising a polyvinyl alcohol resin (a polymer containing -CH2-CHOH- as repeating units. In particular, a polarizer selected from at least one of the groups comprising polyvinyl alcohol and ethylene-vinyl alcohol copolymers) is preferred.

[0697] In this invention, the thickness of the polarizer is not particularly limited, preferably 3 to 60 μm, more preferably 5 to 20 μm, and even more preferably 5 to 10 μm.

[0698] In the viewing angle control system of the present invention, the light-absorbing anisotropic thin film and the polarizer can be laminated by adhesives such as adhesive layers and bonding layers, or the first orientation layer and the light-absorbing anisotropic layer described above can be directly coated on the polarizer and laminated.

[0699] [Adhesive layer]

[0700] The adhesive layer in this invention is preferably a transparent and optically isotropic adhesive, the same as the adhesive used in conventional image display devices, typically a pressure-sensitive adhesive.

[0701] In addition to the base material (adhesive), the adhesive layer of the present invention may contain appropriate additives such as crosslinking agents (e.g., isocyanate crosslinking agents and epoxy crosslinking agents), tackifiers (e.g., rosin derivative resins, polyterpene resins, petroleum resins and oil-soluble phenolic resins), plasticizers, fillers, anti-aging agents, surfactants, ultraviolet absorbers, light stabilizers and antioxidants.

[0702] The thickness of the adhesive layer is typically 20–500 μm, preferably 20–250 μm. When it is less than 20 μm, the required adhesive strength and reprocessing suitability are sometimes not achieved, and when it exceeds 500 μm, the adhesive may sometimes protrude or seep out from the peripheral end of the image display device.

[0703] [Adhesive layer]

[0704] Adhesives exhibit their adhesive properties through drying and / or reaction after bonding.

[0705] Polyvinyl alcohol adhesives (PVA adhesives) exhibit adhesive properties upon drying, enabling them to bond materials together.

[0706] Specific examples of curing adhesives that exhibit adhesiveness through reaction include active energy radiation-curing adhesives such as (meth)acrylate adhesives, or cationic polymerization-curing adhesives.

[0707] Examples of curing components in (meth)acrylate adhesives include compounds having (meth)acryloyl groups and compounds having vinyl groups. Furthermore, compounds having epoxy groups or oxobutyl groups can also be used as cationic polymerization curing adhesives. There are no particular limitations on the epoxy group composition, as long as it has at least two epoxy groups within the molecule; various commonly known curable epoxy compounds can be used. Preferred epoxy compounds include, for example, compounds having at least two epoxy groups and at least one aromatic ring within the molecule (aromatic epoxy compounds), or compounds having at least two epoxy groups within the molecule, with at least one of them formed between two adjacent carbon atoms constituting an alicyclic ring (alicyclic epoxy compounds).

[0708] From the viewpoint of heat deformation resistance, UV-curable adhesives that are cured by UV irradiation are preferred.

[0709] The adhesive layer and each layer of the bonding layer can be a layer that has ultraviolet absorption capability by means of ultraviolet absorbers such as salicylate compounds, benzophenol compounds, benzotriazole compounds, cyanoacrylate compounds, nickel complex salt compounds, etc.

[0710] The attachment of adhesive and bonding layers on the light-absorbing anisotropic thin film and / or polarizer is carried out in an appropriate manner.

[0711] As an example, one could cite the following methods: preparing an adhesive solution of about 10 to 40% by weight, which is a single substance or a solvent consisting of a mixture of a base polymer or a combination thereof dissolved or dispersed in a suitable solvent such as toluene or ethyl acetate, and then directly attaching it to a light-absorbing anisotropic film and / or a polarizer by a suitable spreading method such as casting or coating, or transferring it by forming an adhesive layer on a support as described above.

[0712] Furthermore, as a method for attaching adhesive layers and bonding layers to anisotropic light-absorbing films and / or polarizers, the following method can be used: preparing a coating liquid containing a base material for forming the adhesive layer and, as needed, thermally expanding particles, additives, and solvents; directly applying the coating liquid to a support; and pressing and transferring the coating liquid from the support via a release liner to form an adhesive sheet. Alternatively, as a method for attaching adhesive layers and bonding layers to anisotropic light-absorbing films and / or polarizers, the following method can be used: applying the aforementioned coating liquid to a suitable release liner (release paper, etc.) to form a thermally expanding adhesive layer; and pressing and transferring the thermally expanding adhesive layer from the release liner.

[0713] The adhesive layer and bonding layer can also be disposed on one or both sides of the light-absorbing anisotropic film and / or polarizer as overlapping layers of different compositions or types. Furthermore, when disposed on both sides, adhesive layers of different compositions, types, and thicknesses can be formed on the surface and back of the light-absorbing anisotropic film and / or polarizer.

[0714] Furthermore, the light-absorbing anisotropic film and / or polarizer can undergo surface modification treatment to improve adhesion and other properties before the application of adhesives and binders. Specific treatments include corona treatment, plasma treatment, primer treatment, and saponification treatment.

[0715] The image display device of the present invention provides a viewing angle control system of the present invention on at least one main surface of the display panel.

[0716] In the image display device of the present invention, the angle φ formed by the plane containing the transmittance central axis of the light-absorbing anisotropic layer and the normal of the light-absorbing anisotropic thin film and the absorption axis of the polarizer is preferably 45° to 90°, more preferably 80° to 90°, and even more preferably 88° to 90°.

[0717] The closer the angle φ is to 90°, the better it can give the display image of the image-based display device an illumination contrast between the easy-to-observe and difficult-to-observe directions.

[0718] [Display Panel]

[0719] The display panel used in the image display device of the present invention is not particularly limited, and examples include liquid crystal cells, organic electroluminescent (hereinafter referred to as "EL") display panels, and plasma display panels. Among them, liquid crystal cells or organic EL display panels are preferred. That is, the image display device of the present invention is preferably a liquid crystal display device that uses liquid crystal cells as the display panel and an organic EL display device that uses organic EL display panels as the display panel.

[0720] As an example of the image display device of the present invention, a liquid crystal display device is preferably provided that has the above-described viewing angle control system (light-absorbing anisotropic thin film and polarizer) and liquid crystal cell of the present invention.

[0721] Furthermore, in this invention, the polarizers provided on both sides of the liquid crystal cell are preferably the polarizers of the viewing angle control system of this invention, serving as either the front or rear polarizers. Alternatively, the polarizers of the viewing angle control system of this invention can also be used as both the front and rear polarizers.

[0722] In display panels, the film is thin and can be formed on curved surfaces. The light-absorbing anisotropic film of the present invention is thin and easily foldable, and therefore is also preferably suitable for image display devices with curved display surfaces.

[0723] Furthermore, the pixel density in the display panel exceeds 250 ppi, enabling high-definition display. The light-absorbing anisotropic thin film of this invention does not produce interference ripples and is therefore also preferably suitable for such high-definition display panels.

[0724] The liquid crystal unit that constitutes a liquid crystal display device will be described in detail below.

[0725] [Liquid Crystal Unit]

[0726] The liquid crystal cells used in the liquid crystal display device are preferably in VA (Vertical Alignment) mode, OCB (Optically Compensated Bend) mode, IPS (In-Plane-Switching) mode or TN (Twisted Nematic) mode, but are not limited to these.

[0727] In TN mode liquid crystal cells, the rod-shaped liquid crystal molecules are substantially horizontally oriented when no voltage is applied, and then twisted to an orientation of 60–120°. TN mode liquid crystal cells are most commonly used in color TFT (Thin Film Transistor) liquid crystal display devices, and are documented in several publications.

[0728] In a VA-mode liquid crystal cell, the rod-shaped liquid crystal molecules are substantially vertically oriented when no voltage is applied. In a VA-mode liquid crystal cell, in addition to the narrow definition of a VA-mode liquid crystal cell which has rod-shaped liquid crystal molecules substantially vertically oriented when no voltage is applied and substantially horizontally oriented when a voltage is applied (as described in Japanese Patent Application Publication No. 2-176625), there are also (2) a liquid crystal cell in which the VA mode is multi-domainized (MVA mode) in order to expand the viewing angle (as described in SID97, Digest of Tech. Papers 28 (1997) 845), (3) a liquid crystal cell in which rod-shaped liquid crystal molecules are substantially vertically oriented when no voltage is applied and twisted into multi-domain orientation when a voltage is applied (n-ASM mode) (as described in the proceedings of the Japan Liquid Crystal Conference 58-59 (1998)), and (4) a SURVIVAL mode liquid crystal cell (published in LCD International 98).

[0729] Furthermore, the liquid crystal cell can be any of the following types: PVA (Patterned Vertical Alignment), Optical Alignment, and PSA (Polymer-Sustained Alignment). Detailed information regarding these types can be found in Japanese Patent Application Publication Nos. 2006-215326 and 2008-538819.

[0730] In IPS-mode liquid crystal cells, rod-shaped liquid crystal molecules are substantially parallel to the substrate. By applying an electric field parallel to the substrate surface, the liquid crystal molecules exhibit planar response. Regarding the IPS mode, black is displayed without an applied electric field, and the absorption axes of the upper and lower polarizers are orthogonal to each other. Regarding the IPS mode, methods for using optical compensation sheets to reduce light leakage and improve viewing angle when displaying black in an oblique direction are disclosed in Japanese Patent Application Publications Nos. 10-54982, 11-202323, 9-292522, 11-133408, 11-305217, and 10-307291.

[0731] In the image display device of the present invention, when it is necessary to attach the display unit and the viewing angle control system of the present invention, the attachment is performed by a known method, such as the method of attaching the light-absorbing anisotropic thin film to the polarizer in the above-described viewing angle control system.

[0732] Example

[0733] The present invention will be further described in detail below with examples. The materials, reagents, quantities, proportions, and operations shown in the following examples can be appropriately modified without departing from the spirit of the invention. Therefore, the scope of the present invention is not limited to the specific examples below.

[0734] [Example 1]

[0735] The following describes the fabrication of a light-absorbing anisotropic thin film with an organic dichroic material tilted towards an anisotropic light-absorbing layer.

[0736] <Fabrication of the second transparent support with orientation layer>

[0737] The surface of cellulose acylated membrane 1 (a 40 μm thick TAC substrate; manufactured by TG40 FUJIFILM Co., Ltd.) was saponified with an alkaline solution, and the coating solution 1 for forming the second orientation layer described below was applied onto it using a wire rod. The support with the coating film was dried under warm air at 60°C for 60 seconds, and then dried under warm air at 100°C for 120 seconds, thereby forming the second orientation layer 1, and obtaining a TAC film with the second orientation layer.

[0738] The thickness of the second orientation layer is 0.5 μm.

[0739] After the surface of the second orientation layer is rubbed, the fabricated TAC film with the second orientation layer is used.

[0740]

[0741] Modified polyvinyl alcohol

[0742] [Chemical Formula 45]

[0743]

[0744] <Fabrication of the First Orientation Layer>

[0745] Using a wire rod, a first orientation layer forming composition T1 with the following composition is applied to the second orientation layer of a fabricated TAC film with a second orientation layer, thereby forming a first orientation layer coating layer T1.

[0746] Next, the first orientation layer coating T1 is heated at 120°C for 30 seconds and then cooled to room temperature (23°C). Additionally, it is heated at 80°C for 60 seconds and then cooled again to room temperature.

[0747] Then, using an LED light (center wavelength 365nm) at an illuminance of 200mW / cm² 2Irradiated for 1 second under the specified irradiation conditions, a first orientation layer T1 was formed on the second orientation layer 1. Hereinafter, the fabricated support with the first orientation layer T1 will be referred to as the support Z1 with the first orientation layer.

[0748] The thickness of the first orientation layer T1 is 0.60 μm.

[0749]

[0750] Low molecular weight liquid crystal compound M-1

[0751] [Chemical Formula 46]

[0752]

[0753] Surfactant F-1

[0754] [Chemical Formula 47]

[0755]

[0756] (Determination of the orientation angle on the air interface side of the first orientation layer)

[0757] like Figure 5 Conceptually, a 2μm thick section 43 was produced by cutting the fabricated support Z1 with the first orientation layer parallel to the thickness direction (normal direction) using a slicing machine (Leica Camera AG, rotary slicing machine: RM2265).

[0758] For this slice 43, the orientation angle of the liquid crystal compound in the air interface side of the first alignment layer T1 was measured from the cut surface side using a polarizing microscope. That is, for this slice 43, the angle between the orientation axis (optical axis) of the liquid crystal compound in the air interface side of the first alignment layer T1 and the normal of the first alignment layer T1 was measured from the cut surface side. The interface on the air side of the first alignment layer T1 is the interface on the light absorption anisotropic layer side that will be formed later.

[0759] Regarding measurements based on polarizing microscopy, such as Figure 6 Conceptually, a polarizer and analyzer are positioned in an orthogonal Nicol array. The azimuth angle of slice 43 is moved, and the azimuth angle of extinction on the air interface side of the first alignment layer T1 is observed. Then, a sensitive color plate (λ plate) is inserted, and the color near the interface is observed. The direction of the slow axis within slice 43 is adjusted to determine the alignment angle of the liquid crystal compound at the air interface. Furthermore, three slices 43 are cut to measure the alignment angle of the liquid crystal compound (n=3), and their average value is taken as the alignment angle of the liquid crystal compound on the air interface side of the first alignment layer T1.

[0760] In this example, the orientation angle of the liquid crystal compound in the air interface side of the first orientation layer T1 is 22° relative to the normal direction of the first orientation layer.

[0761] In addition, in the following examples, the orientation angle of the liquid crystal compound at the air interface side (light absorption anisotropic layer side) of the first orientation layer T1 was also measured in the same way.

[0762] The orientation angles of the liquid crystal compounds are shown in Table 1 below.

[0763] <Formation of the light-absorbing anisotropic layer P1>

[0764] The following light-absorbing anisotropic layer forming composition P1 is applied onto the obtained first orientation layer T1 using a wire rod to form a coating layer P1.

[0765] Next, the coating layer P1 is heated at 120°C for 30 seconds, and then cooled to room temperature (23°C).

[0766] Next, heat at 80°C for 60 seconds, and then cool again to room temperature.

[0767] Then, using an LED light (center wavelength 365nm) at an illuminance of 200mW / cm² 2 Irradiation for 1 second under the specified irradiation conditions resulted in the formation of a light-absorbing anisotropic layer P1 on the orientation layer 1.

[0768] The resulting light-absorbing anisotropic layer P1 has a thickness of 1.4 μm and a surface energy of 26.5 mN / m.

[0769] Regarding surface energy, the contact angle between pure water and diiodomethane was measured using an automated contact angle measuring instrument (CA-V type, manufactured by Kyowa Interface Science Co., Ltd.) in an indoor environment of 25°C and 50% RH, and the measurement was performed according to the OVENS and Wendt method.

[0770]

[0771]

[0772] Dichroic substance D-1

[0773] [Chemical Formula 48]

[0774]

[0775] Dichroic substance D-2

[0776] [Chemical Formula 49]

[0777]

[0778] Dichroic substance D-3

[0779] [Chemical Formula 50]

[0780]

[0781] P-1, a polymeric liquid crystal compound

[0782] [Chemical Formula 51]

[0783]

[0784] Surfactant F-2

[0785] [Chemical Formula 52]

[0786]

[0787] <Formation of barrier layer B1>

[0788] The following barrier layer forming composition B1 is applied onto the prepared light-absorbing anisotropic layer P1 using a wire rod and dried at 80°C for 5 minutes to form the barrier coating layer B1.

[0789] Next, under conditions of 100 ppm oxygen concentration and 60°C temperature, LED lights (center wavelength 365 nm) were used at an illuminance of 150 mW / cm². 2 Under the irradiation conditions, the barrier coating layer B1 is irradiated for 2 seconds, thereby forming the barrier layer B1 on the light absorption anisotropic layer P1.

[0790] The thickness of the barrier layer B1 is 1.0 μm.

[0791] It was used as a light-absorbing anisotropic thin film P1.

[0792]

[0793] Modified polyvinyl alcohol

[0794] [Chemical Formula 53]

[0795]

[0796] <Determination of the angle θ of the central axis of transmittance of the light-absorbing anisotropic layer>

[0797] For the fabricated light-absorbing anisotropic thin film P1, the Mueller matrix of the light-absorbing anisotropic layer at a wavelength of 550 nm was measured using an AxoScan OPMF-1 (manufactured by Opto Science, Inc.), thereby determining the angle θ of the central axis of the transmittance of the light-absorbing anisotropic layer.

[0798] The Mueller matrix was measured at 15 randomly selected locations within the sample surface using a sample size of 20cm × 30cm.

[0799] As mentioned above, the transmittance center axis represents the direction with the highest transmittance when the slope angle (polar angle) and slope direction (azimuth angle) of the normal direction relative to the main surface of the light-absorbing anisotropic layer are changed to measure transmittance.

[0800] In the measurement, the azimuth angle of the transmissivity center axis tilt was initially sought.

[0801] Next, the Mueller matrix was measured in a plane (containing the transmittance central axis and orthogonal to the surface of the layer) containing the normal direction of the light-absorbing anisotropic layer along its azimuth angle, with the angle relative to the normal direction of the light-absorbing anisotropic film, i.e., the polar angle θ, was changed by 1° until -70 to 70°.

[0802] From the measurement results of the Mueller matrix, the angle θ at which transmittance becomes a maxima is derived. This angle θ is the direction of the transmittance central axis of the light-absorbing anisotropic layer, that is, the angle between the transmittance central axis of the light-absorbing anisotropic layer and the normal of the light-absorbing anisotropic layer.

[0803] The average value of the angle θ measured at the 15 locations was calculated, and this average value was set as the angle between the central axis of the transmittance of the anisotropic light-absorbing layer in the light-absorbing thin film and the normal of the anisotropic light-absorbing layer. Hereinafter, this angle is set as the average angle θ of the central axis of transmittance.

[0804] The average angle θ of the transmittance center axis is shown in Table 1 below.

[0805] Furthermore, the average angle θ of the transmittance central axis was also measured for each of the anisotropic light absorption films shown below. The results are similarly presented in Table 1.

[0806] <Creation of Layer A1>

[0807] A polarizer 1 with a thickness of 8 μm and exposing one side of the polarizer was fabricated using the same method as that described in International Publication No. 2015 / 166991 for a polarizer 02 with a protective film on one side.

[0808] The exposed polarizer surface of the polarizer 1 and the surface of the fabricated anisotropic light-absorbing film P1 were subjected to corona treatment. Next, the corona-treated surfaces were bonded together using PVA adhesive 1 to form a laminate A1. At this time, as... Figure 4Conceptually, the angle between the plane containing the transmittance center axis 22 of the light-absorbing anisotropic layer 2 and the normal 23 of the light-absorbing anisotropic layer 2 (light-absorbing anisotropic thin film) and the absorption axis 24 of the polarizer 21 is set to 90°.

[0809] (Preparation of PVA adhesive 1)

[0810] A 3.7% aqueous solution was prepared by dissolving 20 parts of hydroxymethyl melamine in pure water at a temperature of 30°C relative to 100 parts of polyvinyl alcohol resin containing acetylacetyl groups (average degree of polymerization: 1200, degree of saponification: 98.5 mol%, degree of acetylacetylation: 5 mol%).

[0811] <Fabrication of Image Display Device B1>

[0812] The LCD unit was removed from an iPad Air Wi-Fi model 16GB (manufactured by Apple Inc.) which is an in-plane switching LCD display device.

[0813] Using the adhesive sheet 1 described above, the laminate A1 is attached to the surface of the polarizer peeled off from the visual recognition side of the liquid crystal cell, so that the polarizer 1 side becomes the liquid crystal cell side. At this time, the direction of the absorption axis of the attached polarizer 1 becomes the length direction of the liquid crystal image.

[0814] After being bonded to the liquid crystal unit, it was reassembled to create the image display device B1.

[0815] (Preparation of Adhesive Sheet 1)

[0816] Acrylate polymers were prepared according to the following steps.

[0817] In a reaction vessel equipped with a cooling pipe, a nitrogen inlet pipe, a thermometer, and a stirring device, 95 parts by weight of butyl acrylate and 5 parts by weight of acrylic acid were polymerized by solution polymerization to obtain an acrylate polymer A1 with an average molecular weight of 2 million and a molecular weight distribution (Mw / Mn) of 3.0.

[0818] Next, in addition to the obtained acrylate polymer A1 (100 parts by mass), a 75% by mass ethyl acetate solution of CORONATEL (trimethylolpropane adduct of toluene diisocyanate, 3 isocyanate groups per molecule, manufactured by Nippon Polyurethane Industry Co., Ltd.) (1.0 parts by mass) and a silane coupling agent KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd.) (0.2 parts by mass) were mixed. Finally, ethyl acetate was added to bring the total solids concentration to 10% by mass to prepare an adhesive forming composition.

[0819] The composition was applied to a separation membrane that had been surface-treated with a silicone-based release agent using a die coater, and dried at 90°C for 1 minute to obtain an acrylic adhesive sheet. The film thickness was 25 μm and the storage modulus was 0.1 MPa.

[0820] [Example 2]

[0821] The composition of the first orientation layer was changed to the composition of the first orientation layer forming composition T2 described below. Otherwise, the light-absorbing anisotropic thin film P2, the laminate A2 and the image display device B2 were fabricated in the same manner as in Example 1.

[0822] The thickness of the first orientation layer is 0.64 μm, and the surface energy is 41.3 mN / m.

[0823] Furthermore, the thickness of the light-absorbing anisotropic layer is 1.4 μm, and the surface energy is 26.5 mN / m.

[0824]

[0825]

[0826] [Example 3]

[0827] The light-absorbing anisotropic layer 3 was formed using the following light-absorbing anisotropic layer forming composition P2, with the film thickness of the light-absorbing anisotropic layer set to 4.0 μm. Otherwise, the light-absorbing anisotropic thin film P3, the laminate A3, and the image display device B3 were fabricated in the same manner as in Example 2.

[0828] Here, using a hot stage for microscopy (METTLER TOLEDO.) and a polarizing microscope, the liquid crystal phases were observed while the temperature was changed, and it was confirmed in advance that the low molecular weight liquid crystal compounds M-2 and M-3 showed smectic phases.

[0829] The thickness of the first orientation layer is 0.64 μm.

[0830]

[0831]

[0832] Low molecular weight liquid crystal compound M-2

[0833] [Chemical Formula 54]

[0834]

[0835] Low molecular weight liquid crystal compound M-3

[0836] [Chemical Formula 55]

[0837]

[0838] [Example 4]

[0839] The light-absorbing anisotropic layer 4 was formed using the following light-absorbing anisotropic layer forming composition P3, with the film thickness of the light-absorbing anisotropic layer set to 4.0 μm. Otherwise, the light-absorbing anisotropic thin film P4, the laminate A4, and the image display device B4 were fabricated in the same manner as in Example 2.

[0840] Here, using a hot stage for microscopy (METTLER TOLEDO.) and a polarizing microscope, the liquid crystal phases were observed while the temperature was changed, and it was confirmed in advance that the low molecular weight liquid crystal compounds M-4 and M-5 showed smectic phases.

[0841] The thickness of the first orientation layer is 0.64 μm.

[0842]

[0843]

[0844] Low molecular weight liquid crystal compound M-4

[0845] [Chemical Formula 56]

[0846]

[0847] Low molecular weight liquid crystal compound M-5

[0848] [Chemical Formula 57]

[0849]

[0850] [Example 5]

[0851] The light-absorbing anisotropic layer 5 was formed using the following light-absorbing anisotropic layer forming composition P4, with the film thickness of the light-absorbing anisotropic layer set to 1.4 μm. Otherwise, the light-absorbing anisotropic thin film P5, the laminate A5, and the image display device B5 were fabricated in the same manner as in Example 2.

[0852] The thickness of the first orientation layer is 0.64 μm.

[0853]

[0854]

[0855] [Example 6]

[0856] The light-absorbing anisotropic layer 6 was formed using the following light-absorbing anisotropic layer forming composition P5, with the film thickness of the light-absorbing anisotropic layer set to 1.4 μm. Otherwise, the light-absorbing anisotropic thin film P6, the laminate A6, and the image display device B6 were fabricated in the same manner as in Example 2.

[0857] The thickness of the first orientation layer is 0.64 μm.

[0858]

[0859] [Comparative Example 1]

[0860] Without a second alignment layer, the following photoalignment layer forming composition is coated onto a PVA alignment layer that has not undergone rubbing treatment, and then dried at 90°C for 1 minute to form a coating film E1 of the photoalignment layer forming composition. The coating film E1 is then exposed to oblique ultraviolet light at a 30° angle from above the photoalignment film relative to its normal to form the photoalignment layer E1.

[0861] The light orientation layer 1 was set as the formation surface of the light absorption anisotropic layer. Otherwise, the light absorption anisotropic thin film P7, the laminate A7 and the image display device B7 were fabricated in the same manner as in Example 1.

[0862] The thickness of the photo-aligned film is 0.1 μm.

[0863]

[0864]

[0865] Photo-alignment material E-1

[0866] [Chemical Formula 58]

[0867]

[0868] [Performance Evaluation]

[0869] (1) Evaluation of the transmittance center axis

[0870] For the fabricated anisotropic light-absorbing thin films P1 to P7, the variation coefficient of angle θ was calculated from the measured angle θ of the central axis of transmittance at 15 locations and the average value of angle θ (mean angle θ). The variation coefficient is the value obtained by dividing the standard deviation by the mean value; the larger the value, the greater the deviation.

[0871] The coefficient of variation of angle θ is considered to be the main cause of uneven brightness within the plane, and they are ranked as follows.

[0872] AAA: The coefficient of variation is less than 9%.

[0873] AA: The coefficient of variation is 10% or more but less than 12%.

[0874] A: The coefficient of variation is above 12% but less than 15%.

[0875] B: The coefficient of variation is above 15% but less than 20%.

[0876] C: The coefficient of variation is above 20% but less than 25%.

[0877] D: The coefficient of variation is 25% or higher.

[0878] (2) Evaluation of brightness non-uniformity in image display devices

[0879] Using image display devices B1 to B7 manufactured through the above steps, sample images are displayed on the screen, thereby evaluating the unevenness of brightness from the front through sensory evaluation.

[0880] AAA: The unevenness in brightness is very obvious.

[0881] AA: Less uneven brightness.

[0882] A: The uneven brightness is not noticeable.

[0883] B: The uneven brightness is slightly noticeable.

[0884] C: Uneven brightness is noticeable.

[0885] D: The uneven brightness is very noticeable.

[0886] The evaluation results are summarized in Table 1.

[0887] [Table 1]

[0888]

[0889] The orientation angle of the liquid crystal compound in the first alignment layer is the same as the orientation angle of the liquid crystal compound at the interface on the air side (light absorption anisotropy layer side).

[0890] According to the light-absorbing anisotropic thin film of the present invention, which has a first orientation layer adjacent to the light-absorbing anisotropic layer, the coefficient of variation (relative value of deviation) of the direction θ of the transmittance central axis and the brightness non-uniformity of the displayed image are smaller compared with the comparative example, thus obtaining a high-quality image display device.

[0891] Among them, the light-absorbing anisotropic thin film using polymer liquid crystal on the first orientation layer and the light-absorbing anisotropic thin film with a high content of organic dichroic substances in the light-absorbing anisotropic layer have particularly small variation coefficient (deviation) of angle θ and small brightness non-uniformity of the displayed image, resulting in excellent quality.

[0892] Furthermore, in the light absorption anisotropic thin film and image display device using liquid crystal compounds displaying smectic phases in the light absorption anisotropic layer, the coefficient of variation of angle θ and the brightness non-uniformity are also small and of high quality.

[0893] Furthermore, as the coefficient of variation of angle θ decreases, the brightness deviation of the image displayed by the image display device also decreases, indicating their corresponding relationship.

[0894] These results show that the present invention avoids the burden of exposure equipment costs and achieves uniform control of viewing angle characteristics.

[0895] Symbol Explanation

[0896] 100-Liquid crystal display device, 101-Light absorption anisotropic thin film, 102-Vision recognition side polarizer, 103-Liquid crystal cell, 104-Back light side polarizer, 105-Back light, 1-Blocking layer, 2-Light absorption anisotropic layer, 3-First alignment layer, 4-Second alignment layer, 5-TAC film, 11-Liquid crystal molecule, 13-Dichroic dye D-1, 14-Dichroic dye D-2, 15-Dichroic dye D-3, 21-Polarizer, 22-Transmittance center axis direction (polar angle θ), 23-Normal of light absorption anisotropic layer, 24-Absorption axis direction of polarizer.

Claims

1. A light-absorbing anisotropic thin film, comprising: Anisotropic light-absorbing layer; and The first orientation layer is adjacent to the light absorption anisotropic layer. The light-absorbing anisotropic layer contains liquid crystal compounds and organic dichroic substances. The angle between the transmittance central axis of the light-absorbing anisotropic layer and the normal of the light-absorbing anisotropic layer is greater than 5° and less than 45°. The first alignment layer is a layer formed by fixing a polymeric liquid crystal compound with a mixed orientation in which the alignment direction in the thickness direction continuously changes from one surface side to another. The ratio of the organic dichroic material to the total solid content of the light-absorbing anisotropic layer is 20-30% by mass.

2. The light-absorbing anisotropic thin film according to claim 1, wherein, The first orientation layer is a layer formed from a composition having polymerizable polymer liquid crystals.

3. The light-absorbing anisotropic thin film according to claim 1 or 2, wherein, The angle between the orientation axis of the polymeric liquid crystal compound at the interface of the first orientation layer on the light-absorbing anisotropic layer side and the normal of the first orientation layer is 2° to 50°.

4. The light-absorbing anisotropic thin film according to claim 1 or 2, wherein, The liquid crystal compound contained in the light-absorbing anisotropic layer is a polymeric liquid crystal compound, which comprises: repeating units having mesocrystalline groups and electron-withdrawing groups with σp values ​​greater than 0 at their ends, and repeating units having mesocrystalline groups and groups with σp values ​​less than 0 at their ends.

5. The light-absorbing anisotropic thin film according to claim 1 or 2, wherein, The liquid crystal compound of the light-absorbing anisotropic layer comprises a polymeric liquid crystal compound, and the polymeric liquid crystal compound comprises a liquid crystal compound displaying a smectic phase.

6. The light-absorbing anisotropic thin film according to claim 1 or 2, wherein, A second orientation layer, formed of polyvinyl alcohol or polyimide, is adjacent to the side of the first orientation layer opposite to the side of the light-absorbing anisotropic layer.

7. A viewing angle control system comprising a polarizer and a light-absorbing anisotropic thin film according to any one of claims 1 to 6.

8. An image display device having a viewing angle control system as claimed in claim 7 disposed on at least one main surface of a display panel.

Images