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

Abstract

The present invention addresses the problem of providing: a light absorbing anisotropic film capable of displaying a bright, clear image in a desired direction and hiding the image in other directions in an image display device; a viewing angle control system using said light absorbing anisotropic film; and an image display device using the same. This problem is solved by a light absorbing anisotropic film, which has a light absorbing anisotropic layer including a liquid crystal compound and an organic dichroic substance, and in which the difference between an angle θA and an angle θB is 15° or less, the angle θA being 5° or more and less than 45°, wherein: θA is an angle formed by the normal of the light absorbing anisotropic layer and an orientation direction of a light absorption axis of the organic dichroic substance in one surface of the light absorbing anisotropic layer; and θB is an angle formed by the normal of the light absorbing anisotropic layer and the orientation direction of the light absorption axis of the dichroic substance on the other surface of the light absorbing anisotropic layer.

Description

Technical Field

[0001] The present invention relates to a light absorption anisotropic film for viewing angle control, a viewing angle control system using this light absorption anisotropic film, and an image display device using this viewing angle control system.

Background Art

[0002] When using an in-vehicle display such as a car navigation system, there is a problem that light emitted upward from the display screen is reflected on the front glass or the like and becomes an obstacle during driving. For the purpose of solving such a problem, for example, Patent Document 1 proposes a method of using in combination a first polarizer having an absorption axis in the plane and a second polarizer (light absorption anisotropic layer) in which the absorption axis of the organic dichroic substance is oriented at 0° to 45° with respect to the normal direction. Here, as the first polarizer, the polarizer on the viewing side in the liquid crystal display device can be used. In this method, only the light from the image in a specific direction is transmitted, and the transmission of light at other angles is blocked, so that the image can be observed by an observer in a desired direction, but the image cannot be seen from other directions, for example, from a direction with a window glass.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above-described viewing angle control method, the light transmittance when observed from the direction in which the image is desired to be visible is insufficient and sufficient visibility cannot be obtained. On the other hand, when observed from other directions, that is, the light transmittance in the direction in which the screen is desired to be made invisible is not sufficiently reduced, so there is a problem that the screen cannot be sufficiently shielded.

[0005] For example, in an in-vehicle application, it is difficult to see the screen clearly and quickly from a direction where it is desired to accurately view information, such as the direction of the driver or the passenger in the passenger seat. On the other hand, the image can be seen from a direction where it is desired to eliminate the reflection on the window glass, resulting in an insufficient anti-reflection effect. This poses a serious problem that hinders safe driving in an in-vehicle display system.

[0006] Therefore, an object of the present invention is to provide a light absorption anisotropic film that provides an image that is sufficiently bright and easy to view from a desired direction, blocks the light of the image from other directions, and can sufficiently limit the reflection on the window glass in an in-vehicle application or the like, a viewing angle control system using this light absorption anisotropic film, and an image display device using this viewing angle control system.

Means for Solving the Problems

[0007] The present inventors have found that the above problems can be achieved by the following configuration.

[0008] (1) A light absorption anisotropic film having a light absorption anisotropic layer, the light absorption anisotropic layer contains a liquid crystal compound and an organic dichroic substance, assuming that the angle formed by the normal of the light absorption anisotropic layer and the orientation direction of the light absorption axis of the organic dichroic substance on one surface of the light absorption anisotropic layer is θA, and the angle formed by the normal of the light absorption anisotropic layer and the orientation direction of the light absorption axis of the dichroic substance on the other surface of the light absorption anisotropic layer is θB, a light absorption anisotropic film in which the difference between the angle θA and the angle θB is 15° or less, and the angle θA is 5° or more and less than 45°. (2) The light absorption anisotropic film according to (1), wherein the difference between the angle θA and the angle θB is 5° or less. (3) The light absorption anisotropic film according to (1) or (2), wherein the difference between the angle θA and the angle θB is 2° or less. (4) The light absorption anisotropic film according to any one of (1) to (3), wherein the ratio of the organic dichroic substance to the total solid mass of the light absorption anisotropic layer of the organic dichroic substance is 5% by mass or more. (5) The light absorption anisotropic film according to any one of (1) to (3), wherein the ratio of the organic dichroic substance to the total solid mass of the light absorption anisotropic layer of the organic dichroic substance is 15% by mass or more. (6) The light absorption anisotropic film according to any one of (1) to (5), wherein the organic dichroic substance is composed of a mixture of three or more organic dichroic substances having different absorption peak wavelengths. (7) The light absorption anisotropic film according to any one of (1) to (6), wherein the liquid crystal compound contains a polymer liquid crystal compound. (8) The light absorption anisotropic film according to any one of (1) to (7), wherein the liquid crystal compound is a polymer of a polymerizable liquid crystal compound. (9) The light absorption anisotropic film according to (8), wherein the polymerizable liquid crystal compound contains a rod-shaped liquid crystal compound. (10) The light absorption anisotropic film according to (8) or (9), wherein the polymerizable liquid crystal compound contains a liquid crystal compound exhibiting a smectic phase. (11) It has an alignment liquid crystal layer adjacent to the light absorption anisotropic layer, The alignment liquid crystal layer is a layer formed by fixing a hybrid-aligned polymerizable liquid crystal compound in which the alignment direction in the thickness direction continuously changes from one surface side to the other surface side. The light absorption anisotropic film according to any one of (1) to (11). (12) The liquid crystal compound of the light absorption anisotropic layer is a polymer of a polymerizable liquid crystal compound, The polymerizable liquid crystal compound used in the light absorption anisotropic layer and the polymerizable liquid crystal compound used in the alignment liquid crystal layer are the same polymerizable liquid crystal compound. The light absorption anisotropic film according to (11). (13) The light absorption anisotropic film according to (11) or (12), wherein the thickness of the alignment liquid crystal layer is 0.1 to 2.0 μm. (14) The light absorption anisotropic film according to any one of (11) to (13), which has an alignment layer made of polyvinyl alcohol or polyimide adjacent to the side opposite to the light absorption anisotropic layer of the alignment liquid crystal layer. A viewing angle control system having a polarizer and the light absorption anisotropic film according to any one of (1) to (14). (16) An image display device in which the viewing angle control system according to (15) is disposed on at least one main surface of a display panel.

Advantages of the Invention

[0009] According to the present invention, when used in an in-vehicle display or the like, it is possible to provide an image that is bright and easy to visually recognize for a driver or the like while sufficiently suppressing the reflection of the image on a window glass or the like.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0011] Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, a numerical range represented by "~" means a range including the numerical values described before and after "~" as the lower limit value and the upper limit value. Also, in this specification, parallel and orthogonal do not mean parallel and orthogonal in a strict sense, but mean a range of ±5° from parallel or orthogonal. Furthermore, in this specification, "(meth)acrylate" is used to mean "either one or both of acrylate and methacrylate".

[0012] Also, in this specification, the liquid crystal composition and the liquid crystal compound conceptually include those that no longer exhibit liquid crystallinity due to curing or the like.

[0013] <Image display device> In the present invention, as the image display device, in addition to a liquid crystal display device, an organic electroluminescence display device, and other display devices can be used. Here, as an example, a liquid crystal display device will be described. As shown in FIG. 1, the liquid crystal display device 100 of the present invention is a liquid crystal display device including, from the viewing side, at least a light absorption anisotropic film 101, a viewing side polarizer 102, a liquid crystal cell 103, a backlight side polarizer 104, and a backlight 105 in this order. The light absorption anisotropic film 101 is the light absorption anisotropic film of the present invention and has a light absorption anisotropic layer.

[0014] As long as the light absorption anisotropic film 101 has a light absorption anisotropic layer to be described later, various configurations can be used. Although not limited to this configuration, the light absorption anisotropic film 101 of the present invention, as an example, has a barrier layer 1, a light absorption anisotropic layer 2, a liquid crystal layer 3 for alignment, an alignment layer 4, and a TAC film 5 in this order, as conceptually shown in FIG. 2. The TAC film 5 is a support for supporting the light absorption anisotropic layer 101. Note that the TAC film is an abbreviation for a triacetylcellulose film.

[0015] In the present invention, the direction of the absorption axis of the polarizer may be referred to as the vertical direction or the horizontal direction. Usually, in the state of using a liquid crystal display device, the direction of the side of the liquid crystal display device close to the vertical direction is referred to as the vertical direction, and the direction of the side of the liquid crystal display device close to the horizontal direction is referred to as the horizontal direction.

[0016] 〔Light absorption anisotropic layer〕 In order to control the light transmission direction of the light absorption anisotropic layer, it is preferable to orient an organic dichroic substance having absorption in the visible region in a desired direction, and it is more preferable to orient the organic dichroic substance by utilizing the alignment of a liquid crystal compound. As an example, a light absorption anisotropic layer in which at least one organic dichroic substance is inclined and aligned with respect to the normal direction of the film can be mentioned. Hereinafter, specifically, the method of determining the alignment direction of the organic dichroic substance will be described. As is well known, the normal line is a direction perpendicular to the main surface of a sheet-like object (film, layer, membrane, plate-like object). For example, in the light absorption anisotropic film shown in FIG. 2, it is the stacking direction of each layer. Also, as is well known, the main surface is the largest surface of the sheet-like object, and usually, it is both surfaces in the thickness direction.

[0017] In the light absorption anisotropic film of the present invention, in the light absorption anisotropic layer, when the angle formed by the alignment direction of the light absorption axis of the organic dichroic substance on one surface and the normal line of the light absorption anisotropic layer is θA, and the angle formed by the alignment direction of the light absorption axis of the dichroic substance on the other surface of the light absorption anisotropic layer and the normal line of the light absorption anisotropic layer is θB, the difference between the angle θA and the angle θB is 15° or less, and the angle θA is 5° or more and less than 45°. The organic dichroic substance is aligned. Preferably, as an example, when the light absorption anisotropic film has a support (TAC film 5) as shown in FIG. 2, as conceptually shown in FIG. 5, at the support-side interface 32 of the light absorption anisotropic layer 2, the angle 34 formed by the orientation direction of the light absorption axis of the organic dichroic substance and the normal line 35 of the light absorption anisotropic layer 2 is defined as the angle θA. Also, at the air-layer-side interface 31 of the light absorption anisotropic layer 2, the angle 33 formed by the orientation direction of the light absorption axis of the dichroic substance and the normal line 35 of the light absorption anisotropic layer 2 is defined as the angle θB. In the light absorption anisotropic layer 2 of the light absorption anisotropic film of the present invention, at such angles θA and θB, the difference between the angle θA and the angle θB is 15° or less, and the angle θA is 5° or more and less than 45°. However, the interface on the side opposite to the support of the light absorption anisotropic layer is not limited to the air layer, and as shown in FIG. 2, it may have various functional layers such as a protective layer like the barrier layer 1. That is, in the light absorption anisotropic layer 2 of the light absorption anisotropic film of the present invention, the difference in the orientation direction in the thickness direction of the dichroic substance on both surfaces is small.

[0018] In the light absorption anisotropic layer 2 of the light absorption anisotropic film of the present invention, the orientation direction (azimuth angle) of the dichroic substance in the plane direction of the light absorption anisotropic layer is the same in both surfaces. Usually, the light absorption anisotropic layer 2 is formed on an alignment film in which a liquid crystal compound is aligned (uniaxially aligned) in one direction. Also, the orientation direction of the liquid crystal compound in the plane direction follows the liquid crystal compound on the alignment film side in the thickness direction. Therefore, in the light absorption anisotropic layer 2, the light distribution direction of the liquid crystal compound in the plane direction is the same in the entire thickness direction. As will be described later, the light absorption anisotropic layer 2 of the light absorption anisotropic film of the present invention is formed using a manufacturing technique of a guest-host liquid crystal cell using a liquid crystal compound as a host, etc. Therefore, the orientation of the organic dichroic substance follows the orientation of the liquid crystal compound. Therefore, the light distribution direction of the dichroic substance in the plane direction is also the same in the entire thickness direction, and the orientation direction (azimuth angle) of the chromatic substance is equal (substantially equal) on both surfaces.

[0019] Here, the orientation direction of the optical absorption axis of the organic dichroic substance refers to the orientation direction of the organic dichroic substance in which linearly polarized light with the vibration direction of the electric field in that direction is most strongly absorbed. As a specific measurement method for the orientation direction of the optical absorption axis of the organic dichroic substance, first, by using AxoScan OPMF-1 (manufactured by Opto Science Co., Ltd.), the Mueller matrix at a wavelength of 550 nm is actually measured to detect the transmission rate central axis of the light absorption anisotropic layer. More specifically, first, using AxoScan OPMF-1, first find the azimuth angle at which the transmission rate central axis is inclined. Next, while changing the polar angle, which is the angle with respect to the normal direction of the light absorption anisotropic layer, by 1° from -70 to 70° in the plane including the normal direction of the light absorption anisotropic layer along the detected azimuth angle, the Mueller matrix at a wavelength of 550 nm is actually measured to derive the transmission rate of the light absorption anisotropic layer. Note that the plane including the normal direction of the light absorption anisotropic layer along the detected azimuth angle is, that is, a plane including the transmission rate central axis and orthogonal to the main plane of the light absorption anisotropic layer. As a result, the direction with the highest transmission rate is taken as the transmission rate central axis. The transmission rate central axis means, that is, the direction in which the optical absorption axis (long axis direction of the molecule) of the dichroic substance contained in the light absorption anisotropic layer is inclined. Next, as conceptually shown in FIG. 6, using a microtome or the like, the light absorption anisotropic film 101 is thinly sliced in parallel with the normal 42 so as to include the detected transmission rate central axis of the light absorption anisotropic layer, thereby thinly slicing the light absorption anisotropic layer 2 in parallel with the normal of the layer (see the normal 35 in FIG. 5) to produce a sample section 43. Next, the sliced section 43 is placed on the rotating sample stage of the polarizing microscope so that the layer cross section faces upward. Then, as conceptually shown in FIG. 7, while rotating the azimuth angle of the section 43, the change in brightness at each position of the sliced section 43 is observed. Utilizing the fact that when the optical absorption axis of the organic dichroic substance and the vibration direction of the electric field of the incident polarized light are parallel, the polarized light is most strongly absorbed and that location becomes dark, the orientation direction of the optical absorption axis of the organic dichroic substance at each location of the light absorption anisotropic layer is estimated. At this time, the analyzer of the polarizing microscope is not used. In the present invention, these optical measurements are performed using light with a wavelength of 550 nm as described above, unless otherwise specified.

[0020] However, it is difficult in practice to observe the direction of the light absorption axis at both surfaces of the light absorption anisotropic layer, for example, at the positions of the interfaces on the support side and the air side, because of large variations. Therefore, as shown in FIG. 5, the angle θA, which is the angle formed by the orientation direction of the light absorption axis of the organic dichroic substance on the support side and the normal line 35 of the light absorption anisotropic layer 2, is defined as the angle 34 at a position 0.2 μm deeper into the air side interface 31 direction than the support side interface 32 of the original light absorption anisotropic layer 2. Similarly, for the angle θB at the air side interface, as shown in FIG. 5, the angle 33 formed by the orientation direction of the light absorption axis of the organic dichroic substance and the normal line 35 of the light absorption anisotropic layer at a position 0.2 μm deeper into the support side interface 32 direction than the air side interface 31 of the original light absorption anisotropic layer 2 is defined as the angle θB.

[0021] In the present invention, by setting the difference between the angle θA and the angle θB to 15° or less, the light transmittance in the observer direction of the image is increased to improve the image visibility, and at the same time, the transmittance in other directions is decreased to suppress the reflection on window glass and the like. The difference between the angle θA and the angle θB is determined in relation to, for example, the effectiveness of suppressing the reflection of the image display device when it is determined from the arrangement inside the vehicle including the image display device how the image can be viewed from which direction in an in-vehicle image display device. When the difference between the angle θA and the angle θB exceeds 15°, in the image display device, the visibility from the set viewing direction deteriorates, the light blocking property in directions other than the set viewing direction is insufficient, and inconveniences such as increased reflection on window glass in in-vehicle applications occur. The difference between the angle θA and the angle θB is preferably 10° or less, more preferably 5° or less, still more preferably 2° or less, and most preferably 0°.

[0022] The angles θA and θB are determined in relation to when the effectiveness of suppressing the reflection of the image display device is maximized when determining, for example, in in-vehicle applications, from what directions the image can be viewed, based on the arrangement inside the vehicle including the image display device. Specifically, when the angle of the angle θA is 5° or more and less than 45°, the effectiveness is the highest. Also, either the angle θA or the angle θB may have a larger value. The angle θA is determined by the need for which direction of viewing angle control is desired in the viewing angle control system in which the light absorption anisotropic film of the present invention is used. In the present invention, when the angle θA is less than 5°, inconveniences such as a narrow design freedom of the in-vehicle arrangement including the image display device occur. Also, even if the angle θA is set to 45° or more, from such a shallow angle, the screen is difficult to view, and moreover, in the front direction where the luminance of the emitted light from the image display device is high and the optical path length of the optical path crossing the optically anisotropic layer is short, the light-shielding property is also insufficient. That is, when the angle θA is 45° or more, it is not preferable from the viewpoint of the viewing angle control direction of the viewing angle control system, the visibility from the set viewing direction deteriorates, the light-blocking property in directions other than the set viewing direction is insufficient, and inconveniences such as an increase in reflection on the window glass in in-vehicle applications occur. The angle θA is preferably 5° to 30°, more preferably 5° to 15°.

[0023] Techniques for orienting the organic dichroic substance in a desired direction can refer to techniques for manufacturing polarizers using organic dichroic substances, techniques for manufacturing guest-host liquid crystal cells, and the like. That is, in the light absorption anisotropic film of the present invention, the light absorption anisotropic layer has a liquid crystal compound and an organic dichroic substance. As an example, like the light absorption anisotropic layer 2 conceptually shown in FIG. 3, by orienting the liquid crystal compound 11 so as to satisfy the above-described angles θA and θB, using the liquid crystal compound 11 as a host, the dichroic substances D-1 indicated by reference numeral 13, the dichroic substance D-2 indicated by reference numeral 14, and the dichroic substance D-3 indicated by reference numeral 15, which are guests, are oriented along the liquid crystal compound. Note that the dichroic substances D-1, D-2, and D-3 are, for example, organic dichroic substances having different absorption peak wavelengths from each other. Such an orientation of the dichroic substance can be used, for example, in the method for producing a dichroic polarizing element described in JP-A-11-305036 and JP-A-2002-90526, and the techniques used in the method for producing a guest-host type liquid crystal display device described in JP-A-2002-99388 and JP-A-2016-27387, for producing the light absorption anisotropic layer used in the light absorption anisotropic film of the present invention.

[0024] For example, by utilizing the technology of a guest-host type liquid crystal cell, the molecules of the organic dichroic substance can be oriented in a desired orientation as described above in association with the orientation of the host liquid crystal. Specifically, an organic dichroic substance serving as a guest and a rod-shaped liquid crystal compound serving as a host liquid crystal are mixed, the host liquid crystal is oriented, and the molecules of the organic dichroic substance are oriented along the orientation of the liquid crystal compound, and the orientation state is fixed, whereby the light absorption anisotropic layer used in the present invention can be produced.

[0025] In order to prevent fluctuations in the light absorption characteristics of the light absorption anisotropic layer used in the present invention due to the use environment, it is preferable to fix the orientation of the organic dichroic substance by forming a chemical bond. For example, the orientation can be fixed by promoting the polymerization of the host liquid crystal, the organic dichroic substance, or a polymerizable component added as desired.

[0026] Further, a guest-host type liquid crystal cell itself having a liquid crystal layer containing at least an organic dichroic substance and a host liquid crystal on a pair of substrates may be used as the light absorption anisotropic layer used in the present invention. The alignment of the host liquid crystal (and the alignment of the associated organic dichroic substance molecules) can be controlled by an alignment film formed on the inner surface of the substrate. Unless an external stimulus such as an electric field is applied, the alignment state is maintained, and the light absorption characteristics of the light absorption anisotropic layer used in the present invention can be made constant.

[0027] Also, by infiltrating an organic dichroic substance into a polymer film and aligning the organic dichroic substance along the alignment 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 film of the present invention can be produced. Specifically, it can be produced by applying a solution of an organic dichroic substance to the surface of a polymer film and infiltrating it into the film. The alignment of the organic dichroic substance can be adjusted by the alignment of the polymer chains in the polymer film, its properties (chemical and physical properties such as polymer chains or functional groups they have), the coating method, and the like. Details of this method are described in Japanese Patent Application Laid-Open No. 2002-090526.

[0028] Even when this polymer film is used as the light absorption anisotropic layer, the alignment direction of the light absorption axis of the organic dichroic substance may be measured in the same manner as before.

[0029] The light absorption anisotropic layer used in the present invention preferably has a transmittance (hereinafter 550 nm) inclined 30° from the transmittance central axis of 60% or less, more preferably 50% or less, and even more preferably 45% or less. Thereby, it becomes possible to increase the contrast of the illuminance between the transmittance center and the direction deviated from the transmittance center, and the viewing angle can be made sufficiently narrow.

[0030] The light absorption anisotropic layer used in the present invention preferably has a transmittance of the transmittance central axis of 65% or more, more preferably 75% or more, and even more preferably 85% or more. Thereby, the illuminance at the viewing angle center of the image display device can be increased and the visibility can be improved.

[0031] In addition, in terms of being able to neutralize the color tone in the front direction, it is preferable that the degree of alignment at 420 nm of the light absorption anisotropic layer satisfies 0.93 or more. Regarding the color tone control of the light absorption anisotropic film containing the dichroic substance, it is usually carried out by adjusting the addition amount of the dichroic substance contained in the film. However, it has been found that it is not possible to make the color tones in both the front and diagonal directions neutral only by adjusting the addition amount of the dichroic substance. It has been found that the reason why the color tones in the front and diagonal directions cannot be made neutral is that the degree of alignment at 420 nm is low, and by increasing the degree of alignment at 420 nm to a high level, the color tones in the front and diagonal directions can be made neutral.

[0032] In addition, the light absorption anisotropic layer used in the present invention may be formed by laminating a plurality of light absorption anisotropic layers having different transmission axis centers or laminating a retardation layer so as to satisfy the transmittance inclined by 30° from the transmission rate central axis and the transmittance of the transmission rate central axis. By laminating a plurality of light absorption anisotropic layers having different transmission axis centers, the width of the region with high transmittance can be adjusted. When laminating a retardation layer, the transmission and light shielding performance can be controlled by controlling the retardation value and the optical axis direction. As the retardation layer, a positive A plate, a negative A plate, a positive C plate, a negative C plate, a B plate, an O plate, etc. can be used. From the viewpoint of thinning the viewing angle control system, the thickness of the retardation layer is preferably thin as long as it does not impair the optical characteristics, mechanical physical properties, and manufacturing suitability. Specifically, 1 to 150 μm is preferable, 1 to 70 μm is more preferable, and 1 to 30 μm is even more preferable.

[0033] As described above, the light absorption anisotropic layer contains a liquid crystal compound and an organic dichroic substance. The liquid crystal compound preferably contains a polymer liquid crystal compound, and as will be described later, particularly preferably contains a polymer liquid crystal compound of a rod-shaped liquid crystal compound. By containing a polymer liquid crystal compound in the liquid crystal compound, the difference between the above-described angle θA and angle θB can be reduced, and the effects of the present invention can be obtained more preferably. Furthermore, the liquid crystal compound is preferably a polymer of a polymerizable liquid crystal compound. In particular, it is preferable that the polymerizable liquid crystal compound contains a rod-like liquid crystal compound, and it is also preferable that the polymerizable liquid crystal compound exhibits a smectic phase. Making the liquid crystal compound a polymer of a polymerizable liquid crystal compound is preferable in terms of being able to increase the physical strength of the light absorption anisotropic layer. Note that the polymerizable liquid crystal compound means a liquid crystal compound having a polymerizable group.

[0034] [Liquid crystal compound] Liquid crystal compounds can generally be classified into rod-like types and disc-like types according to their shapes. The liquid crystal composition of the present invention may be either a rod-like type (rod-like liquid crystal compound) or a disc-like type (disc-like liquid crystal compound), but a rod-like liquid crystal compound is preferable in terms of being easier to control the alignment direction of the dichroic substance. When controlling the alignment direction of the dichroic substance with a rod-like liquid crystal compound, the dichroic substance tends to be oriented in a direction parallel to the alignment direction of the rod-like liquid crystal compound. Therefore, by controlling the alignment direction of the rod-like liquid crystal compound, the alignment direction of the dichroic substance can also be controlled. On the other hand, when trying to control the alignment direction of the dichroic substance with a disc-like liquid crystal compound, the molecular long axis direction of the dichroic substance becomes parallel to the disc plane of the disc-like liquid crystal compound, but it is difficult to control the alignment direction of the dichroic substance within the disc plane. Therefore, it is difficult to control the alignment direction of the dichroic substance in a desired direction, and alignment defects of the dichroic substance are also likely to occur. As the rod-like liquid crystal compound, a low-molecular compound liquid crystal compound (low-molecular liquid crystal compound) may be used, or a polymer liquid crystal compound in which a rod-like liquid crystal compound is introduced into the main chain or side chain of a high-molecular compound may be used. Also, a low-molecular liquid crystal compound and a high-molecular liquid crystal compound may be used in combination. Also, as the rod-like liquid crystal compound, a liquid crystal compound that does not exhibit dichroism in the visible region is preferable.

[0035] As the rod-shaped liquid crystal compound, either a low-molecular liquid crystal compound or a high-molecular liquid crystal compound can be used. Here, the "low-molecular liquid crystal compound" refers to a liquid crystal compound having no repeating unit in its chemical structure. Further, the "high-molecular liquid crystal compound" refers to a liquid crystal compound having a repeating unit in its chemical structure. Examples of the low-molecular liquid crystal compound include the liquid crystal compounds described in JP-A-2013-228706. Examples of the high-molecular liquid crystal compound include the thermotropic liquid crystalline polymer described in JP-A-2011-237513. Further, the high-molecular liquid crystal compound may have a crosslinkable group (for example, an acryloyl group and a methacryloyl group) at its terminal.

[0036] The rod-shaped liquid crystal compound may be used alone or in combination of two or more. The rod-shaped liquid crystal compound can reduce the difference between the above-described angle θA and angle θB, and preferably contains a high-molecular liquid crystal compound, and more preferably contains both a high-molecular liquid crystal compound and a low-molecular liquid crystal compound, from the viewpoint that the effects of the present invention are more excellent.

[0037] The rod-shaped liquid crystal compound preferably contains a liquid crystal compound represented by the formula (LC) or a polymer thereof. Both the liquid crystal compound represented by the formula (LC) and its polymer are compounds exhibiting liquid crystallinity. The liquid crystallinity may be a nematic phase or a smectic phase, or may exhibit both a nematic phase and a smectic phase. The liquid crystal compound preferably contains a liquid crystal compound exhibiting a smectic phase. When the smectic liquid crystal phase exhibited by the liquid crystal compound is these smectic liquid crystal phases, it is preferable because a light absorption anisotropic layer having a higher degree of orientation order can be produced. The smectic phase may be a higher-order smectic phase. The higher-order smectic phase referred to herein means a smectic B phase, a smectic D phase, a smectic E phase, a smectic F phase, a smectic G phase, a smectic H phase, a smectic I phase, a smectic J phase, a smectic K phase, a smectic L phase, and among them, the smectic B phase, the smectic F phase, and the smectic I phase are preferable. When the smectic liquid crystal phase exhibited by the liquid crystal compound is one of these higher-order smectic liquid crystal phases, it is preferable because an optical absorption anisotropic layer with a higher degree of alignment order can be produced. Further, the optical absorption anisotropic layer produced from such a higher-order smectic liquid crystal phase with a high degree of alignment order can obtain Bragg peaks derived from higher-order structures such as a hexatic phase and a crystal phase in X-ray diffraction measurement. The above Bragg peak is a peak derived from the surface periodic structure of the molecular orientation, and according to the liquid crystal composition of the present invention, an optical absorption anisotropic layer with a periodic interval of 3.0 to 5.0 Å can be obtained.

[0038] [Chemical formula]

[0039] In formula (LC), Q1 and Q2 are each independently a hydrogen atom, a halogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, an alkynyl group having 1 to 20 carbon atoms, an aryl group having 1 to 20 carbon atoms, a heterocyclic group (which may also be referred to as a hetero ring group), a cyano group, a hydroxy group, a nitro group, a carboxy group, an aryloxy group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an amino group (including an anilino group), an ammonio group, an acylamino group, an aminocarbonylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkyl or arylsulfonylamino group, a mercapto group, an alkylthio group, an arylthio group, a heterocyclic thio group, a sulfamoyl group, a sulfo group, an alkyl or arylsulfinyl group, an alkyl or arylsulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an aryl or heterocyclic azo group, an imide group, a phosphino group, a phosphinyl group, a phosphinyloxy group, a phosphinylamino group, a phosphono group, a silyl group, a hydrazino group, a ureido group, a boronic acid group (-B(OH)2), a phosphato group (-OPO(OH)2), a sulfato group (-OSO3H), or a crosslinkable group represented by the following formulas (P-1) to (P-30), and it is preferable that at least one of Q1 and Q2 is a crosslinkable group represented by the following formula.

[0040]

Chemical formula

[0041] In formulas (P-1) to (P-30), R Prepresents a hydrogen atom, a halogen atom, a linear, branched, or cyclic alkylene group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, an alkynyl group having 1 to 20 carbon atoms, an aryl group having 1 to 20 carbon atoms, a heterocyclic group (which may also be referred to as a hetero ring group), a cyano group, a hydroxy group, a nitro group, a carboxy group, an aryloxy group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an amino group (including an anilino group), an ammonium group, an acylamino group, an aminocarbonylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkyl or arylsulfonylamino group, a mercapto group, an alkylthio group, an arylthio group, a heterocyclic thio group, a sulfamoyl group, a sulfo group, an alkyl or arylsulfinyl group, an alkyl or arylsulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an aryl or heterocyclic azo group, an imide group, a phosphino group, a phosphinyl group, a phosphinyloxy group, a phosphinylamino group, a phosphono group, a silyl group, a hydrazino group, a ureido group, a boronic acid group (-B(OH)2), a phosphato group (-OPO(OH)2), or a sulfato group (-OSO3H), and a plurality of R P may be the same or different from each other. Preferred embodiments of the crosslinkable group include a radical-polymerizable group or a cationic-polymerizable group. Preferred radical-polymerizable groups include the vinyl group represented by the above formula (P-1), the butadiene group represented by the above formula (P-2), the (meth)acrylic group represented by the above formula (P-4), the (meth)acrylamide group represented by the above formula (P-5), the vinyl acetate group represented by the above formula (P-6), the fumaric acid ester group represented by the above formula (P-7), the styryl group represented by the above formula (P-8), the vinyl pyrrolidone group represented by the above formula (P-9), maleic anhydride represented by the above formula (P-11), or the maleimide group represented by the above formula (P-12). Preferred cationic-polymerizable groups include the vinyl ether group represented by the above formula (P-18), the epoxy group represented by the above formula (P-19), or the oxetanyl group represented by the above formula (P-20).

[0042] In formula (LC), S1 and S2 each independently represent a divalent spacer group. Preferred embodiments of S1 and S2 are the same as the structure of SPW in the above formula (W1), so the description thereof is omitted.

[0043] In formula (LC), MG represents a mesogenic group described later. The mesogenic group represented by MG is a group showing the main skeleton of a liquid crystal compound contributing to liquid crystal formation. A liquid crystal compound shows liquid crystallinity in a state intermediate between a crystalline state and an isotropic liquid state (mesophase). There is no particular limitation on the mesogenic group. For example, reference can be made to "Flussige Kristalle in Tabellen II" (VEB Deutsche Verlag fur Grundstoff Industrie, Leipzig, published in 1984), particularly the description on pages 7 to 16, and "Liquid Crystal Handbook" edited by the Liquid Crystal Handbook Editorial Committee (Maruzen, published in 2000), particularly the description in Chapter 3. The mesogenic group represented by MG preferably contains 2 to 10 cyclic structures, more preferably 3 to 7 cyclic structures. Specific examples of the cyclic structure include an aromatic hydrocarbon group, a heterocyclic group, and an alicyclic group.

[0044] As the mesogenic group represented by MG, from the viewpoints of the expression of liquid crystallinity, the adjustment of the liquid crystal phase transition temperature, the availability of raw materials, and synthetic suitability, and since the effects of the present invention are more excellent, a group represented by the following formula (MG-A) or the following formula (MG-B) is preferable, and a group represented by the formula (MG-B) is more preferable.

[0045] [Chemical formula]

[0046] In the formula (MG-A), A1 is a divalent group selected from the group consisting of an aromatic hydrocarbon group, a heterocyclic group, and an alicyclic group. These groups may be substituted with substituents such as the substituent W. The divalent group represented by A1 is preferably a 4- to 15-membered ring. Further, the divalent group represented by A1 may be a monocyclic ring or a condensed ring. * represents the bonding position with S1 or S2.

[0047] Examples of the divalent aromatic hydrocarbon group represented by A1 include a phenylene group, a naphthylene group, a fluorene-diyl group, an anthracene-diyl group, and a tetracene-diyl group. From the viewpoints of the diversity of the design of the mesogenic skeleton and the availability of raw materials, a phenylene group and a naphthylene group are preferable.

[0048] The divalent heterocyclic group represented by A1 may be either aromatic or non-aromatic, but from the viewpoint of further improving the degree of orientation, it is preferably a divalent aromatic heterocyclic group. Examples of the atoms other than carbon constituting the divalent aromatic heterocyclic group include a nitrogen atom, a sulfur atom, and an oxygen atom. When the aromatic heterocyclic group has a plurality of atoms other than carbon constituting the ring, these may be the same or different. Specific examples of the divalent aromatic heterocyclic group include, for example, a pyridylene group (pyridine-diyl group), a pyridazine-diyl group, an imidazole-diyl group, a thienylene (thiophene-diyl group), a quinolyrene group (quinoline-diyl group), an isoquinolyrene group (isoquinoline-diyl group), an oxazole-diyl group, a thiazole-diyl group, an oxadiazole-diyl group, a benzothiazole-diyl group, a benzothiadiazole-diyl group, a phthalimide-diyl group, a thienothiazole-diyl group, a thiazolothiazole-diyl group, a thienothiophene-diyl group, and a thienooxazole-diyl group, the following structures (II-1) to (II-4), and the like.

[0049] [Chemical formula]

[0050] In formulas (II-1) to (II-4), D1 represents -S-, -O-, or NR 11 -, R 11 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, Y1 represents an aromatic hydrocarbon group having 6 to 12 carbon atoms, or an aromatic heterocyclic group having 3 to 12 carbon atoms, and Z1, Z2, and Z3 each independently represent a hydrogen atom, an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, -NR 12 R 13 or -SR 12 represents, Z1 and Z2 may be bonded to each other to form an aromatic ring or an aromatic heterocyclic ring, and R 12 and R 13 each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and J1 and J2 each independently represent -O-, -NR 21 -(R 21represents a hydrogen atom or a substituent.), represents a group selected from the group consisting of -S- and C(O)-, E represents a hydrogen atom or a Group 14-16 non-metal atom to which a substituent may be bonded, Jx represents an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring, Jy represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring. The aromatic rings of Jx and Jy may have substituents, and Jx and Jy may be bonded to form a ring. D2 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent.

[0051] In formula (II-2), when Y1 is an aromatic hydrocarbon group having 6 to 12 carbon atoms, it may be monocyclic or polycyclic. When Y1 is an aromatic heterocyclic group having 3 to 12 carbon atoms, it may be monocyclic or polycyclic. In formula (II-2), when J1 and J2 are -NR 21 -, for the substituent of R 21 reference can be made to the descriptions in paragraphs

[0035] to

[0045] of JP-A-2008-107767, and this content is incorporated herein by reference. In formula (II-2), when E is a Group 14-16 non-metal atom to which a substituent may be bonded, =O, =S, =NR', =C(R')R' are preferred. R' represents a substituent, and for the substituent, reference can be made to the descriptions in paragraphs

[0035] to

[0045] of JP-A-2008-107767, -NZ A1 Z A2 (Z A1 and Z A2 each independently represents a hydrogen atom, an alkyl group or an aryl group.) is preferred.

[0052] Specific examples of the divalent alicyclic group represented by A1 include a cyclopentylene group and a cyclohexylene group. The carbon atoms may be substituted by -O-, -Si(CH3)2-, -N(Z)- (where Z represents hydrogen, an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group, an aryl group, a cyano group, or a halogen atom), -C(O)-, -S-, -C(S)-, -S(O)-, and -SO2-, or a group formed by combining two or more of these groups.

[0053] In formula (MG-A), a1 represents an integer from 2 to 10. A plurality of A1s may be the same or different.

[0054] In formula (MG-B), A2 and A3 are each independently a divalent group selected from the group consisting of an aromatic hydrocarbon group, a heterocyclic group, and an alicyclic group. Specific examples and preferred embodiments of A2 and A3 are the same as those of A1 in formula (MG-A), and thus the description thereof is omitted. In formula (MG-B), a2 represents an integer from 1 to 10. A plurality of A2s may be the same or different, and a plurality of LA1s may be the same or different. For reasons of more excellent effects of the present invention, a2 is more preferably 2 or more. In formula (MG-B), LA1 is a single bond or a divalent linking group. However, when a2 is 1, LA1 is a divalent linking group, and when a2 is 2 or more, at least one of the plurality of LA1s is a divalent linking group. In formula (MG-B), since the divalent linking group represented by LA1 is the same as LW, the description thereof is omitted.

[0055] Specific examples of MG include, for example, the following structures. In the following structures, the hydrogen atoms on the aromatic hydrocarbon group, heterocyclic group, and alicyclic group may be substituted by the above-described substituent W.

[0056]

Chemical formula

[0057]

Chemical formula

[0058]

Chem.

[0059] <Low-molecular liquid crystal compound> When the liquid crystal compound represented by the formula (LC) is a low-molecular liquid crystal compound, preferred embodiments of the cyclic structure of the mesogenic group MG include a cyclohexylene group, a cyclopentylene group, a phenylene group, a naphthylene group, a fluorene-diyl group, a pyridine-diyl group, a pyridazine-diyl group, a thiophene-diyl group, an oxazole-diyl group, a thiazole-diyl group, a thienothiophene-diyl group, etc. The number of cyclic structures is preferably 2 to 10, more preferably 3 to 7. Preferred embodiments of the substituent W of the mesogenic structure include a halogen atom, a halogenated alkyl group, a cyano group, a hydroxy group, a nitro group, a carboxy group, an alkoxy group having 1 to 10 carbon atoms, an alkylcarbonyl group having 1 to 10 carbon atoms, an alkyloxycarbonyl group having 1 to 10 carbon atoms, an alkylcarbonyloxy group having 1 to 10 carbon atoms, an amino group, an alkylamino group having 1 to 10 carbon atoms, an alkylaminocarbonyl group, a group in which LW is a single bond, SPW is a divalent spacer group, and Q is a crosslinkable group represented by the above (P-1) to (P-30), etc. Preferred crosslinkable groups include a vinyl group, a butadiene group, a (meth)acrylic group, a (meth)acrylamide group, a vinyl acetate group, a fumaric acid ester group, a styryl group, a vinylpyrrolidone group, maleic anhydride, a maleimide group, a vinyl ether group, an epoxy group, an oxetanyl group.

[0060] Since the preferred embodiments of the divalent spacer groups S1 and S2 are the same as those of the above SPW, the description thereof is omitted. When using a low-molecular liquid crystal compound showing a smectic phase, the number of carbon atoms of the spacer group (when this carbon is replaced by "SP-C", the number of its atoms) is preferably 6 or more, more preferably 8 or more.

[0061] When the liquid crystal compound represented by the formula (LC) is a low-molecular liquid crystal compound, a plurality of low-molecular liquid crystal compounds may be used in combination, preferably 2 to 6 kinds are used in combination, and more preferably 2 to 4 kinds are used in combination. By using low-molecular liquid crystal compounds in combination, the solubility can be improved and the phase transition temperature of the liquid crystal composition can be adjusted.

[0062] Specific examples of the low-molecular liquid crystal compounds include compounds represented by the following formulas (LC-1) to (LC-77), but the low-molecular liquid crystal compounds are not limited thereto.

[0063]

Chemical formula

[0064]

Chemical formula

[0065] <High-molecular liquid crystal compound> The high-molecular liquid crystal compound is preferably a homopolymer or copolymer containing a repeating unit described later, and may be any polymer such as a random polymer, a block polymer, a graft polymer, or a star polymer.

[0066] (Repeating unit (1)) The high-molecular liquid crystal compound preferably contains a repeating unit represented by the formula (1) (hereinafter, also referred to as "repeating unit (1)").

[0067]

Chemical formula

[0068] In the formula (1), PC1 represents the main chain of the repeating unit, L1 represents a single bond or a divalent linking group, SP1 represents a spacer group, MG1 represents the mesogen group MG in the above formula (LC), and T1 represents a terminal group.

[0069] As the main chain of the repeating unit represented by PC1, for example, groups represented by the formulas (P1-A) to (P1-D) can be mentioned. Among them, from the viewpoints of the diversity of the monomer as a raw material and ease of handling, the group represented by the following formula (P1-A) is preferable.

[0070]

Chemical formula

[0071] In the formulas (P1-A) to (P1-D), "*" represents the bonding position with L1 in the formula (1). In the formulas (P1-A) to (P1-D), R 11 , R 12 , R 13 , R 14 each independently represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. The above alkyl group may be a linear or branched alkyl group, or an alkyl group having a cyclic structure (cycloalkyl group). Further, the number of carbon atoms of the above alkyl group is preferably 1 to 5. The group represented by the formula (P1-A) is preferably one unit of the partial structure of poly(meth)acrylate obtained by polymerization of (meth)acrylate. The group represented by the formula (P1-B) is preferably an ethylene glycol unit formed by ring-opening polymerization of the epoxy group of a compound having an epoxy group. The group represented by the formula (P1-C) is preferably a propylene glycol unit formed by ring-opening polymerization of the oxetane group of a compound having an oxetane group. The group represented by the formula (P1-D) is preferably a siloxane unit of polysiloxane obtained by polycondensation of a compound having at least one of an alkoxysilyl group and a silanol group. Here, as the compound having at least one of an alkoxysilyl group and a silanol group, a compound having a group represented by the formula SiR 14 (OR 15 )2- can be mentioned. In the formula, R 14 is R 14is synonymous with a plurality of R 15 each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

[0072] The divalent linking group represented by L1 is the same divalent linking group as LW in the above formula (W1). Preferred embodiments include -C(O)O-, -OC(O)-, -O-, -S-, -C(O)NR 16 -, -NR 16 C(O)-, -S(O)2-, and -NR 16 R 17 - etc. are mentioned. In the formula, R 16 and R 17 each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent (for example, the above-mentioned substituent W). In specific examples of the divalent linking group, the left bond is bonded to PC1 and the right bond is bonded to SP1. When the group represented by PC1 is a group represented by the formula (P1-A), L1 is preferably a group represented by -C(O)O- or -C(O)NR 16 -. When the group represented by PC1 is a group represented by the formulas (P1-B) to (P1-D), L1 is preferably a single bond.

[0073] The spacer group represented by SP1 represents the same group as S1 and S2 in the above formula (LC). From the viewpoint of the degree of orientation, a group containing at least one structure selected from the group consisting of an oxyethylene structure, an oxypropylene structure, a polysiloxane structure, and a fluoroalkylene structure, or a linear or branched alkylene group having 2 to 20 carbon atoms is preferred. However, the above alkylene group may contain -O-, -S-, -O-CO-, -CO-O-, -O-CO-O-, -O-CNR- (R represents an alkyl group having 1 to 10 carbon atoms), or -S(O)2-. The spacer group represented by SP1 is more preferably a group containing at least one structure selected from the group consisting of an oxyethylene structure, an oxypropylene structure, a polysiloxane structure, and a fluoroalkylene structure because it is likely to exhibit liquid crystallinity and for reasons such as the availability of raw materials. Here, the oxyethylene structure represented by SP1 is preferably a group represented by *-(CH2-CH2O) n1 -*. In the formula, n1 represents an integer from 1 to 20, and * represents the bonding position with L1 or MG1. For the reason that the effects of the present invention are more excellent, n1 is preferably an integer from 2 to 10, more preferably an integer from 2 to 6, and most preferably 2 to 4. Also, the oxypropylene structure represented by SP1 is preferably a group represented by *-(CH(CH3)-CH2O) n2 -*. In the formula, n2 represents an integer from 1 to 3, and * represents the bonding position with L1 or MG1. Also, the polysiloxane structure represented by SP1 is preferably a group represented by *-(Si(CH3)2-O) n3 -*. In the formula, n3 represents an integer from 6 to 10, and * represents the bonding position with L1 or MG1. Also, the fluoroalkylene structure represented by SP1 is preferably a group represented by *-(CF2-CF2) n4 -*. In the formula, n4 represents an integer from 6 to 10, and * represents the bonding position with L1 or MG1.

[0074] As the terminal group represented by T1, a hydrogen atom, a halogen atom, a cyano group, a nitro group, a hydroxy group, -SH, a carboxyl group, a boronic acid group, -SO3H, -PO3H2, -NR 11 R 12 (R 11 and R 12 each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, cycloalkyl group, or aryl group having 1 to 10 carbon atoms), an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an alkoxycarbonyloxy group having 1 to 10 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an acylamino group having 1 to 10 carbon atoms, an alkoxycarbonyl group having 1 to 10 carbon atoms, an alkoxycarbonylamino group having 1 to 10 carbon atoms, a sulfonylamino group having 1 to 10 carbon atoms, a sulfamoyl group having 1 to 10 carbon atoms, a carbamoyl group having 1 to 10 carbon atoms, a sulfinyl group having 1 to 10 carbon atoms, and a ureido group having 1 to 10 carbon atoms, a crosslinkable group-containing group, and the like can be mentioned. Examples of the crosslinkable group-containing group include, for example, the above -L-CL. L represents a single bond or a linking group. Specific examples of the linking group are the same as those of LW and SPW described above. CL represents a crosslinkable group, and examples include groups represented by the above Q1 or Q2, and groups represented by the above formulas (P1) to (P30) are preferred. Also, T1 may be a group formed by combining two or more of these groups. For reasons of more excellent 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 may be further substituted with these groups or polymerizable groups described in JP-A-2010-244038. For reasons of more excellent effects 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 degree of orientation of the light absorption anisotropic layer is further improved. Here, the "main chain" in T1 means the longest molecular chain that binds to M1, and hydrogen atoms are not counted in the number of atoms in the main chain of T1. For example, when T1 is an n-butyl group, the number of atoms in the main chain is 4, and when T1 is a sec-butyl group, the number of atoms in the main chain is 3.

[0075] The content of the repeating unit (1) is preferably 40 to 100% by mass, more preferably 50 to 95% by mass, based on all the repeating units (100% by mass) contained in the polymer liquid crystal compound. When the content of the repeating unit (1) is 40% by mass or more, an excellent light absorption anisotropic layer can be obtained due to good orientation. Also, when the content of the repeating unit (1) is 100% by mass or less, an excellent light absorption anisotropic layer can be obtained due to good orientation. The repeating unit (1) may be contained alone or in two or more kinds in the polymer liquid crystal compound. When two or more kinds of the repeating unit (1) are contained, the content of the repeating unit (1) means the total content of the repeating unit (1).

[0076] (logP value) In formula (1), the difference (|logP1 - logP2|) between the logP values of PC1, L1, and SP1 (hereinafter also referred to as "logP1") and the logP value of MG1 (hereinafter also referred to as "logP2") is preferably 4 or more, more preferably 4.25 or more, and even more preferably 4.5 or more from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer. Also, from the viewpoints of adjusting the liquid crystal phase transition temperature and synthesis suitability, the upper limit value of the above difference is preferably 15 or less, more preferably 12 or less, and even more preferably 10 or less. Here, the logP value is an index expressing the hydrophilic and hydrophobic properties of the chemical structure, and may be called a 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 determined experimentally by methods such as those in OECD Guidelines for the Testing of Chemicals, Sections 1, Test No. 117. In the present invention, unless otherwise specified, the value calculated by inputting the structural formula of the compound into HSPiP (Ver. 4.1.07) is adopted as the logP value.

[0077] As described above, the above logP1 means the logP values of PC1, L1, and SP1. The "logP values of PC1, L1, and SP1" means the logP value of the structure integrating PC1, L1, and SP1, and is not the sum of the respective logP values of PC1, L1, and SP1. Specifically, logP1 is calculated by inputting a series of structural formulas from PC1 to SP1 in formula (1) into the above software. However, in calculating logP1, regarding the part of the group represented by PC1 among a series of structural formulas from PC1 to SP1, the structure of the group itself represented by PC1 (for example, the above formulas (P1-A) to (P1-D), etc.) may be used, or the structure of the group that can become PC1 after polymerizing the monomer used to obtain the repeating unit represented by formula (1) may be used. Here, specific examples of the latter (groups that can become PC1) are as follows. When PC1 is obtained by polymerization of (meth)acrylic acid esters, the group represented by CH2=C(R 1 )- (where R 1 represents a hydrogen atom or a methyl group). When PC1 is obtained by polymerization of ethylene glycol, it is ethylene glycol, and when PC1 is obtained by polymerization of propylene glycol, it is propylene glycol. When PC1 is obtained by polycondensation of silanol, it is silanol (a compound represented by the formula Si(R 2 )3(OH). A plurality of R 2 each independently represents a hydrogen atom or an alkyl group. However, at least one of the plurality of R 2 represents an alkyl group).

[0078] When the difference between logP1 and the above-mentioned logP2 is 4 or more, logP1 may be lower than logP2 or higher than logP2. Here, the logP value (the above-mentioned logP2) of a general mesogenic group tends to be in the range of 4 to 6. At this time, 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. When PC1 in the above formula (1) is obtained by polymerization of (meth)acrylic acid esters and logP1 is lower than logP2, the logP value of SP1 in the above formula (1) is preferably 0.7 or less, more preferably 0.5 or less. On the other hand, when PC1 in the above formula (1) is obtained by polymerization of (meth)acrylic acid esters and logP1 is higher than logP2, the logP value of SP1 in the above formula (1) is preferably 3.7 or more, more preferably 4.2 or more. Examples of structures with a logP value of 1 or less include an oxyethylene structure and an oxypropylene structure. Examples of structures with a logP value of 6 or more include a polysiloxane structure and a fluorinated alkylene structure.

[0079] (Repeating units (21) and (22)) From the viewpoint of improving the degree of orientation, the polymeric liquid crystal compound preferably contains a repeating unit having an electron-donating property and / or an electron-withdrawing property at the terminal. More specifically, it is more preferable to include a repeating unit (21) having a mesogenic group and an electron-withdrawing group having a σp value greater than 0 present at the terminal of the mesogenic group, and a repeating unit (22) having a mesogenic group and a group having a σp value of 0 or less present at the terminal of the mesogenic group. Thus, when the polymeric liquid crystal compound contains the repeating unit (21) and the repeating unit (22), the degree of orientation of the light absorption anisotropic layer formed using this is improved as compared with the case where only either the repeating unit (21) or the repeating unit (22) is included. Although the details of this reason are not clear, it is generally estimated as follows. That is, it is presumed that the reverse dipole moments generated in the repeating unit (21) and the repeating unit (22) interact intermolecularly, strengthening the interaction in the short-axis direction of the mesogenic group and making the orientation direction of the liquid crystal more uniform. As a result, it is considered that the degree of order of the liquid crystal increases. Thereby, since the orientation property of the dichroic substance also improves, it is presumed that the degree of orientation of the formed light absorption anisotropic layer becomes high. The repeating units (21) and (22) may be the repeating units represented by the above formula (1).

[0080] The repeating unit (21) has a mesogenic group and an electron-withdrawing group having a σp value greater than 0 present at the terminal of the mesogenic group. The electron-withdrawing group is located at the terminal of the mesogenic group and is a group having a σp value greater than 0. Examples of the electron-withdrawing group (a group having a σp value greater than 0) include the group represented by EWG in the following formula (LCP-21), and specific examples thereof are the same. The σp value of the electron-withdrawing group is greater than 0, and from the viewpoint of further increasing the degree of orientation of the light absorption anisotropic layer, it is preferably 0.3 or more, more preferably 0.4 or more. The upper limit value of the σp value of the electron-withdrawing group is preferably 1.2 or less, more preferably 1.0 or less, from the viewpoint of excellent orientation uniformity.

[0081] The σp value is the Hammett substituent constant σp value (simply abbreviated as "σp value"), which numerically represents the effect of a substituent on the acid dissociation equilibrium constant of substituted benzoic acid, and 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 means the substituent constant σ when the substituent is located at the para position of benzoic acid. For the Hammett substituent constant σp value of each group in this specification, the values described in the literature "Hansch et al., Chemical Reviews, 1991, Vol, 91, No. 2, 165-195" are adopted. For groups for which the Hammett substituent constant σp value is not shown in the above literature, the Hammett substituent constant σp value can be calculated based on the difference between the pKa of benzoic acid and the pKa of a benzoic acid derivative having a substituent at the para position using the software "ACD / ChemSketch (ACD / Labs 8.00 Release Product Version: 8.08)".

[0082] The repeating unit (21) is not particularly limited as long as it has a mesogenic group in the side chain and an electron-withdrawing group having a σp value greater than 0 at the terminal of the mesogenic group. However, from the viewpoint of higher orientation degree of the light absorption anisotropic layer, it is preferably a repeating unit represented by the following formula (LCP-21).

[0083]

Chemical formula

[0084] In formula (LCP-21), PC21 represents the main chain of the repeating unit, more specifically, represents the same structure as PC1 in the above formula (1), L21 represents a single bond or a divalent linking group, more specifically, represents the same structure as L1 in the above formula (1), SP21A and SP21B each independently represent a single bond or a spacer group, and specific examples of the spacer group represent the same structure as SP1 in the above formula (1), MG21 represents a mesogenic structure, more specifically, represents the mesogenic group MG in the above formula (LC), and EWG represents an electron-withdrawing group having a σp value greater than 0.

[0085] The spacer groups represented by SP21A and SP21B represent groups similar to the above formulas S1 and S2, and are preferably groups containing at least one structure selected from the group consisting of an oxyethylene structure, an oxypropylene structure, a polysiloxane structure, and a fluoroalkylene structure, or a linear or branched alkylene group having 2 to 20 carbon atoms. However, the above alkylene group may contain -O-, -O-CO-, -CO-O-, or -O-CO-O-. The spacer group represented by SP1 preferably contains at least one structure selected from the group consisting of an oxyethylene structure, an oxypropylene structure, a polysiloxane structure, and a fluoroalkylene structure because it is likely to exhibit liquid crystallinity and for reasons such as the availability of raw materials.

[0086] SP21B is preferably a single bond or a linear or branched alkylene group having 2 to 20 carbon atoms. However, the above alkylene group may contain -O-, -O-CO-, -CO-O-, or -O-CO-O-. Among these, the spacer group represented by SP21B preferably has a single bond in that the degree of orientation of the light absorption anisotropic layer becomes higher. In other words, the repeating unit 21 preferably has a structure in which the electron-withdrawing group EWG in the formula (LCP-21) is directly bonded to the mesogenic group MG21 in the formula (LCP-21). Thus, when the electron-withdrawing group is directly bonded to the mesogenic group, it is presumed that the intermolecular interaction due to an appropriate dipole moment in the polymer liquid crystal compound acts more effectively, so that the orientation direction of the liquid crystal becomes more uniform. As a result, it is considered that the degree of order of the liquid crystal increases and the degree of orientation becomes higher.

[0087] EWG represents an electron-withdrawing group having a σp value greater than 0. Examples of the electron-withdrawing group having a σp value greater than 0 include an ester group (specifically, a group represented by *-C(O)O-R E ), a (meth)acryloyl group, a (meth)acryloyloxy group, a carboxy group, a cyano group, a nitro group, a sulfo group, -S(O)(O)-OR E , -S(O)(O)-R E , -O-S(O)(O)-R E , an acyl group (specifically, a group represented by *-C(O)R E ), an acyloxy group (specifically, a group represented by *-OC(O)R E ), an isocyanate group (-N=C(O)), *-C(O)N(R F )2, a halogen atom, and an alkyl group substituted with these groups (preferably having 1 to 20 carbon atoms). In each of the above groups, * represents the bonding position to SP21B. R E represents an alkyl group having 1 to 20 carbon atoms (preferably 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms). R F each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms (preferably 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms). Among the above groups, EWG is preferably a group represented by *-C(O)O-R E , a (meth)acryloyloxy group, or a cyano group or a nitro group, in that the effects of the present invention are more exhibited.

[0088] The content of the repeating unit (21) is preferably 60% by mass or less, more preferably 50% by mass or less, and even more preferably 45% by mass or less, based on the total repeating units (100% by mass) of the polymer liquid crystal compound, from the viewpoint of being able to uniformly orient the polymer liquid crystal compound and the dichroic substance while maintaining a high degree of orientation of the light absorption anisotropic layer. The lower limit of the content of the repeating unit (21) is preferably 1% by mass or more, more preferably 3% by mass or more, based on the total repeating units (100% by mass) of the polymer liquid crystal compound, from the viewpoint of more effectively exerting the effects of the present invention. In the present invention, the content of each repeating unit contained in the polymer liquid crystal compound is calculated based on the charged amount (mass) of each monomer used to obtain each repeating unit. The repeating unit (21) may be contained alone or in two or more kinds in the polymer liquid crystal compound. When the polymer liquid crystal compound contains two or more kinds of the repeating unit (21), there are advantages such as improved solubility of the polymer liquid crystal compound in a solvent and easier adjustment of the liquid crystal phase transition temperature. When two or more kinds of the repeating unit (21) are contained, it is preferable that the total amount is within the above range.

[0089] When two or more kinds of the repeating unit (21) are contained, a repeating unit (21) not containing a crosslinkable group in the EWG and a repeating unit (21) containing a polymerizable group in the EWG may be used in combination. Thereby, the curability of the light absorption anisotropic layer is further improved. As the crosslinkable group, a vinyl group, a butadiene group, a (meth)acrylic group, a (meth)acrylamide group, a vinyl acetate group, a fumaric acid ester group, a styryl group, a vinyl pyrrolidone group, maleic anhydride, a maleimide group, a vinyl ether group, an epoxy group, an oxetanyl group are preferable. In this case, from the viewpoint of the balance between the curability and the degree of orientation of the light absorption anisotropic layer, the content of the repeating unit (21) containing a polymerizable group in the EWG is preferably 1 to 30% by mass based on the total repeating units (100% by mass) of the polymer liquid crystal compound.

[0090] In the following, an example of the repeating unit (21) is shown, but the repeating unit (21) is not limited to the following repeating units.

[0091] [Chemical formula]

[0092] As a result of intensive studies on the composition (content ratio) and the electron-donating and electron-withdrawing properties of the end groups of the repeating unit (21) and the repeating unit (22), the present inventors have found that when the electron-withdrawing property of the electron-withdrawing group in the repeating unit (21) is strong (i.e., when the σp value is large), decreasing the content ratio of the repeating unit (21) results in a higher degree of orientation of the light-absorbing anisotropic layer, and when the electron-withdrawing property of the electron-withdrawing group in the repeating unit (21) is weak (i.e., when the σp value is close to 0), increasing the content ratio of the repeating unit (21) results in a higher degree of orientation of the light-absorbing anisotropic layer. Although the details of this reason are not clear, it is generally estimated as follows. That is, it is presumed that the intermolecular interaction due to an appropriate dipole moment in the polymer liquid crystal compound makes the orientation direction of the liquid crystal more uniform, and as a result, the degree of order of the liquid crystal increases, and the degree of orientation of the light-absorbing anisotropic layer becomes higher. Specifically, the product of the σp value of the above 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 above product is within the above range, the degree of orientation of the light-absorbing anisotropic layer becomes higher.

[0093] The repeating unit (22) has a mesogenic group and a group having a σp value of 0 or less present at the end of the above mesogenic group. By having the repeating unit (22) in the polymer liquid crystal compound, the polymer liquid crystal compound and the dichroic substance can be uniformly oriented. The mesogenic group is a group that represents the main skeleton of a liquid crystal compound contributing to liquid crystal formation. Details will be described as MG in the following formula (LCP-22), and specific examples are the same. The above group is located at the end of the mesogenic group and is a group with a σp value of 0 or less. Examples of the above group (a group with a σp value of 0 or less) include a hydrogen atom with a σp value of 0 and a group represented by T22 in the following formula (LCP-22) with a σp value smaller than 0 (an electron-donating group). Among the above groups, specific examples of the group with a σp value smaller than 0 (an electron-donating group) are the same as T22 in the following formula (LCP-22). The σp value of the above group is 0 or less, and from the viewpoint of better orientation uniformity, it is preferably smaller than 0, more preferably -0.1 or less, and even more preferably -0.2 or less. The lower limit value of the σp value of the above group is preferably -0.9 or more, and more preferably -0.7 or more.

[0094] The repeating unit (22) is not particularly limited as long as it has a mesogenic group in the side chain and a group with a σp value of 0 or less present at the end of the above mesogenic group. However, from the viewpoint of higher liquid crystal orientation uniformity, it does not correspond to the repeating unit represented by the above formula (LCP-21), and it is preferably a repeating unit represented by the following formula (PCP-22).

[0095]

Chemical formula

[0096] In formula (LCP-22), PC22 represents the main chain of the repeating unit, more specifically, it represents the same structure as PC1 in the above formula (1). L22 represents a single bond or a divalent linking group, more specifically, it represents the same structure as L1 in the above formula (1). SP22 represents a spacer group, more specifically, it represents the same structure as SP1 in the above formula (1). MG22 represents a mesogenic structure, more specifically, it represents the same structure as the mesogenic group MG in the above formula (LC). T22 represents an electron-donating group with a Hammett substituent constant σp value smaller than 0.

[0097] T22 represents an electron-donating group with a σp value smaller than 0. Examples of the electron-donating group with a σp value smaller than 0 include a hydroxy group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and an alkylamino group having 1 to 10 carbon atoms. When the number of atoms in the main chain of T22 is 20 or less, the degree of orientation of the light-absorbing anisotropic layer is further improved. Here, the "main chain" in T22 means the longest molecular chain that binds to MG22, and hydrogen atoms are not counted in the number of atoms in the main chain of T22. For example, when T22 is an n-butyl group, the number of atoms in the main chain is 4, and when T22 is a sec-butyl group, the number of atoms in the main chain is 3.

[0098] In the following, an example of the repeating unit (22) is shown, but the repeating unit (22) is not limited to the following repeating units.

[0099] [Chemical formula]

[0100] The repeating unit (21) and the repeating unit (22) preferably have a common part in their structures. It is presumed that the more similar the structures of the repeating units are, the more uniformly the liquid crystal aligns. As a result, the degree of orientation of the light-absorbing anisotropic layer becomes higher. Specifically, from the viewpoint of further increasing the degree of orientation of the light-absorbing anisotropic layer, it is preferable that at least one of the following is satisfied: SP21A of the formula (LCP-21) and SP22 of the formula (LCP-22) have the same structure, MG21 of the formula (LCP-21) and MG22 of the formula (LCP-22) have the same structure, and L21 of the formula (LCP-21) and L22 of the formula (LCP-22) have the same structure. More preferably, two or more are satisfied, and particularly preferably, all are satisfied.

[0101] From the viewpoint of excellent orientation uniformity, the content of the repeating unit (22) is preferably 50% by mass or more, more preferably 55% by mass or more, and particularly preferably 60% by mass or more, based on all the repeating units (100% by mass) of the polymer liquid crystal compound. From the viewpoint of improving the degree of orientation, the upper limit of the content of the repeating unit (22) is preferably 99% by mass or less, more preferably 97% by mass or less, based on all the repeating units (100% by mass) of the polymer liquid crystal compound. The repeating unit (22) may be contained alone or in combination of two or more in the polymer liquid crystal compound. When the polymer liquid crystal compound contains two or more repeating units (22), there are advantages such as an improvement in the solubility of the polymer liquid crystal compound in a solvent and an easy adjustment of the liquid crystal phase transition temperature. When two or more repeating units (22) are contained, it is preferable that the total amount thereof is within the above range.

[0102] (Repeating unit (3)) From the viewpoint of improving the solubility in a general-purpose solvent, the polymer liquid crystal compound can contain a repeating unit (3) that does not contain a mesogen. In particular, in order to improve the solubility while suppressing a decrease in the degree of orientation, it is preferable that the repeating unit (3) that does not contain a mesogen has a molecular weight of 280 or less. The reason for being able to improve the solubility while suppressing a decrease in the degree of orientation by including a repeating unit having a molecular weight of 280 or less that does not contain a mesogen is estimated as follows. That is, when the polymer liquid crystal compound contains a repeating unit (3) that does not have a mesogen in its molecular chain, the solvent can easily penetrate into the polymer liquid crystal compound, so the solubility is improved. However, the non-mesogenic repeating unit (3) is considered to decrease the degree of orientation. However, because the molecular weight of the above repeating unit is small, it is presumed that the orientation of the repeating unit (1), repeating unit (21) or repeating unit (22) containing the above mesogen group is not easily disturbed, and a decrease in the degree of orientation can be suppressed.

[0103] The repeating unit (3) is preferably a repeating unit having a molecular weight of 280 or less. The molecular weight of the repeating unit (3) does not mean the molecular weight of the monomer used to obtain the repeating unit (3), but rather means the molecular weight of the repeating unit (3) in the state incorporated into the polymer liquid crystal compound by the polymerization of the monomer. 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, and more preferably 50 or more. When the molecular weight of the repeating unit (3) is 280 or less, the polymer liquid crystal compound has excellent solubility, and a light absorption anisotropic layer with a high degree of alignment can be obtained. On the other hand, when the molecular weight of the repeating unit (3) exceeds 280, the liquid crystal alignment of the portion of the repeating unit (1), repeating unit (21) or repeating unit (22) may be disturbed, and the degree of alignment may decrease. In addition, since it becomes difficult for the solvent to penetrate into the polymer liquid crystal compound, the solubility of the polymer liquid crystal compound may decrease.

[0104] Specific examples of the repeating unit (3) include a repeating unit that does not contain a crosslinkable group (for example, an ethylenically unsaturated group) (hereinafter, also referred to as "repeating unit (3-1)"), and a repeating unit that contains a crosslinkable group (hereinafter, also referred to as "repeating unit (3-2)").

[0105] · Repeating unit (3-1) Specific examples of the monomers used for the polymerization of the repeating unit (3-1) include acrylic acid [72.1], α-alkylacrylic acids (e.g., methacrylic acid [86.1], itaconic acid [130.1]), esters and amides derived therefrom (e.g., N-i-propylacrylamide [113.2], N-n-butylacrylamide [127.2], N-t-butylacrylamide [127.2], N,N-dimethylacrylamide [99.1], N-methylmethacrylamide [99.1], acrylamide [71.1], methacrylamide [85.1], diacetoneacrylamide [169.2], acryloylmorpholine [141.2], N-methylolacrylamide [101.1], N-methylolmethacrylamide [115.1], methyl acrylate [86.0], ethyl acrylate [100.1], hydroxyethyl acrylate [116.1], n-propyl acrylate [114.1], i-propyl acrylate [114.2], 2-hydroxypropyl acrylate [130.1], 2-methyl-2-nitropropyl acrylate [173.2], n-butyl acrylate [128.2], i-butyl acrylate [128.2], t-butyl acrylate [128.2], t-pentyl acrylate [142.2], 2-methoxyethyl acrylate [130.1], 2-ethoxyethyl acrylate [144.2], 2-ethoxyethoxyethyl acrylate [188.2], 2,2,2-trifluoroethyl acrylate [154.1], 2,2-dimethylbutyl acrylate [156.2], 3-methoxybutyl acrylate [158.2], ethyl carbitol acrylate [188.2], phenoxyethyl acrylate [192.2], n-pentyl 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 [130.1], 2-Hydroxypropyl methacrylate [144.2], n-butyl methacrylate [142.2], i-butyl methacrylate [142.2], sec-butyl methacrylate [142.2], n-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-phenyl maleimide [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], t-butylstyrene [160.3], α-methylstyrene [118.2]), N-vinylpyrrolidone [111.1], N-vinyl oxazolidone [113.1], N-vinyl succinimide [125.1], N-vinyl formamide [71.1], N-vinyl-N-methyl formamide [85.1], N-vinyl acetamide [85.1], N-vinyl-N-methyl acetamide [99.1], 1-vinyl imidazole [94.1], 4-vinyl pyridine [105.2], vinyl sulfonic acid [108.1], sodium vinyl sulfonate [130.2], sodium allyl sulfonate [144.1], sodium methallyl 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.Examples include [1]. Note that the numerical value within the brackets represents the molecular weight of the monomer. The above monomers may be used alone or in combination of two or more. Among the above monomers, acrylic acid, α-alkylacrylic acids, esters and amides derived therefrom, acrylonitrile, methacrylonitrile, and aromatic vinyl compounds are preferred. As monomers other than the above, for example, the compounds described in Research Disclosure No. 1955 (July 1980) can be used.

[0106] Hereinafter, specific examples of the repeating unit (3-1) and their molecular weights are shown, but the present invention is not limited to these specific examples.

[0107]

Chemical formula

[0108] ·Repeating unit (3-2) In the repeating unit (3-2), specific examples of the crosslinkable group include the groups represented by the above formulas (P-1) to (P-30), and vinyl group, butadiene group, (meth)acrylic group, (meth)acrylamide group, vinyl acetate group, fumaric acid ester group, styryl group, vinyl pyrrolidone group, maleic anhydride, maleimide group, vinyl ether group, epoxy group, and oxetanyl group are more preferred. From the viewpoint of easy polymerization, the repeating unit (3-2) is preferably a repeating unit represented by the following formula (3).

[0109]

Chemical formula

[0110] 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 linking group, more specifically, it represents the same structure as L1 in the above formula (1), and P32 represents a crosslinkable group represented by the above formulas (P1) to (P30).

[0111] Hereinafter, specific examples of the repeating unit (3-2) and its molecular weight (Mw) are shown, but the present invention is not limited to these specific examples.

[0112]

Chemical formula

[0113] The content of the repeating unit (3) is preferably less than 14% by mass, more preferably 7% by mass or less, and even more preferably 5% by mass or less, based on the total repeating units (100% by mass) of the liquid crystal polymer compound. The lower limit of the content of the repeating unit (3) is preferably 2% by mass or more, more preferably 3% by mass or more, based on the total repeating units (100% by mass) of the liquid crystal polymer compound. If the content of the repeating unit (3) is less than 14% by mass, the degree of orientation of the light absorption anisotropic layer is further improved. If the content of the repeating unit (3) is 2% by mass or more, the solubility of the liquid crystal polymer compound is further improved. The repeating unit (3) may be contained alone or in combination of two or more in the liquid crystal polymer compound. When two or more repeating units (3) are contained, the total amount thereof is preferably within the above range.

[0114] (Repeating unit (4)) The liquid crystal polymer compound can contain a repeating unit (4) having a long and flexible structure of the molecular chain (SP4 in the following formula (4)) from the viewpoints of improving adhesion and planar uniformity. The reason for this is estimated as follows. That is, by including such a long and flexible structure of the molecular chain, entanglement between the molecular chains constituting the polymer liquid crystal compound is likely to occur, and aggregation breakdown of the light absorption anisotropic layer (specifically, breakdown of the light absorption anisotropic layer itself) is suppressed. As a result, it is presumed that the adhesion between the light absorption anisotropic layer and the underlying layer (for example, a substrate or an alignment film) is improved. Further, it is considered that the decrease in planar uniformity occurs because the compatibility between the dichroic substance and the polymer liquid crystal compound is low. That is, when the compatibility between the dichroic substance and the polymer liquid crystal compound is insufficient, planar defects (alignment defects) nucleated by the precipitated dichroic substance are considered to occur. On the other hand, since the polymer liquid crystal compound includes a long and flexible structure of the molecular chain, it is presumed that precipitation of the dichroic substance is suppressed and a light absorption anisotropic layer excellent in planar uniformity is obtained. Here, excellent planar uniformity means that there are few alignment defects generated when the liquid crystal composition containing the polymer liquid crystal compound is repelled on the underlying layer (for example, a substrate or an alignment film).

[0115] The repeating unit (4) is a repeating unit represented by the following formula (4).

[0116] [Chemical formula]

[0117] In the above formula (4), PC4 represents the main chain of the repeating unit, and more specifically, represents the same structure as PC1 in the above formula (1). L4 represents a single bond or a divalent linking group, and more specifically, represents the same structure as L1 in the above formula (1) (a single bond is preferred). SP4 represents an alkylene group having 10 or more carbon atoms in the main chain, and T4 represents a terminal group, and more specifically, represents the same structure as T1 in the above formula (1).

[0118] Specific examples and preferred embodiments of PC4 are the same as those of PC1 in formula (1), and thus the description thereof is omitted.

[0119] As L4, a single bond is preferred from the viewpoint that the effects of the present invention are more exhibited.

[0120] In formula (4), SP4 represents an alkylene group having 10 or more carbon atoms in the main chain. However, one or more -CH2- constituting the alkylene group represented by SP4 may be replaced by the above-mentioned "SP-C", and in particular, -O-, -S-, -N(R 21 )-, -C(=O)-, -C(=S)-, -C(R 22 )=C(R 23 )-, an alkynylene group, -Si(R 24 )(R 25 )-, -N=N-, -C(R 26 )=N-N=C(R 27 )-, -C(R 28 )=N-, and at least one group selected from the group consisting of S(=O)2- is preferably replaced. However, R 21 ~R 28 each independently represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, or a linear or branched alkyl group having 1 to 10 carbon atoms. Further, the hydrogen atom contained in one or more -CH2- constituting the alkylene group represented by SP4 may be replaced by the above-mentioned "SP-H".

[0121] The number of atoms in the main chain of SP4 is 10 or more, and from the viewpoint of obtaining a light absorption anisotropic layer in which at least one of adhesion and planar uniformity is more excellent, 15 or more is preferable, and 19 or more is more preferable. Further, the upper limit of the number of atoms in the main chain of SP2 is preferably 70 or less, more preferably 60 or less, and even more preferably 50 or less from the viewpoint of obtaining a light absorption anisotropic layer having excellent orientation. Here, the "main chain" in SP4 means the partial structure necessary for directly connecting L4 and T4, and the "number of atoms in the main chain" means the number of atoms constituting the above partial structure. In other words, the "main chain" in SP4 is the partial structure in which the number of atoms connecting L4 and T4 is the shortest. For example, when SP4 is a 3,7-dimethyldecanyl group, the number of atoms in the main chain is 10, and when SP4 is a 4,6-dimethyldodecanyl group, the number of atoms in the main chain is 12. Further, in the following formula (4-1), the inside of the frame represented by the dotted square corresponds to SP4, and the number of atoms in the main chain of SP4 (corresponding to the total number of atoms surrounded by the dotted circle) is 11.

[0122]

Chem.

[0123] The alkylene group represented by SP4 may be linear or branched. From the viewpoint of obtaining a light absorption anisotropic layer excellent in the degree of orientation, the number of carbon atoms of the alkylene group represented by SP4 is preferably 8 to 80, more preferably 15 to 80, still more preferably 25 to 70, and particularly preferably 25 to 60.

[0124] From the viewpoint of obtaining a light absorption anisotropic layer excellent in adhesion and planar uniformity, one or more -CH2- constituting the alkylene group represented by SP4 are preferably replaced by the above-mentioned "SP-C". Further, when there are a plurality of -CH2- constituting the alkylene group represented by SP4, from the viewpoint of obtaining a light absorption anisotropic layer excellent in adhesion and planar uniformity, it is more preferable that only a part of the plurality of -CH2- is replaced by the above-mentioned "SP-C".

[0125] Among "SP-C", -O-, -S-, -N(R 21 )-, -C(=O)-, -C(=S)-, -C(R 22 )=C(R 23 )-, alkynylene group, -Si(R 24 )(R 25 )-, -N=N-, -C(R 26 )=N-N=C(R 27 )-, -C(R 28 )=N-, and at least one group selected from the group consisting of -S(=O)2- are preferred, and from the viewpoint of obtaining a light absorption anisotropic layer excellent in adhesion and planar uniformity, at least one group selected from the group consisting of -O-, -N(R 21 )-, -C(=O)-, and S(=O)2- are more preferred, and at least one group selected from the group consisting of -O-, -N(R 21 )-, and C(=O)- are still more preferred. In particular, SP4 is preferably a group containing at least one selected from the group consisting of an oxyalkylene structure in which one or more -CH2- constituting an alkylene group are replaced by -O-, an ester structure in which one or more -CH2-CH2- constituting an alkylene group are replaced by -O- and -C(=O)-, and a urethane bond in which one or more -CH2-CH2-CH2- constituting an alkylene group are replaced by -O-, -C(=O)- and -NH-.

[0126] The hydrogen atom contained in one or more -CH2- constituting the alkylene group represented by SP4 may be replaced by the aforementioned "SP-H". In this case, it is sufficient that one or more of the hydrogen atoms contained in -CH2- are replaced by "SP-H". That is, only one of the hydrogen atoms contained in -CH2- may be replaced by "SP-H", or all (two) of the hydrogen atoms contained in -CH2- may be replaced by "SP-H". Among "SP-H", it is preferably at least one kind of group selected from the group consisting of a halogen atom, a cyano group, a nitro group, a hydroxy group, a linear alkyl group having 1 to 10 carbon atoms and a branched alkyl group having 1 to 10 carbon atoms, and a halogenated alkyl group having 1 to 10 carbon atoms, and more preferably at least one kind of group selected from the group consisting of a hydroxy group, a linear alkyl group having 1 to 10 carbon atoms and a branched alkyl group having 1 to 10 carbon atoms.

[0127] As described above, T4 represents the same end group as T1, which is preferably a hydrogen atom, a methyl group, a hydroxy group, a carboxy group, a sulfonic acid group, a phosphoric acid group, a boronic acid group, an amino group, a cyano group, a nitro group, a phenyl group which may have a substituent, -L-CL (L represents a single bond or a divalent linking group. Specific examples of the divalent linking group are the same as those of LW and SPW described above. CL represents a crosslinkable group, and examples thereof include the groups represented by the above Q1 or Q2, and the crosslinkable groups represented by the formulas (P1) to (P30) are preferred.). As the above CL, a vinyl group, a butadiene group, a (meth)acrylic group, a (meth)acrylamide group, a vinyl acetate group, a fumaric acid ester group, a styryl group, a vinyl pyrrolidone group, maleic anhydride, a maleimide group, a vinyl ether group, an epoxy group, or an oxetanyl group is preferred. The epoxy group may be an epoxy cycloalkyl group, and the number of carbon atoms in the cycloalkyl group portion of the epoxy cycloalkyl group is preferably 3 to 15, more preferably 5 to 12, and even more preferably 6 (that is, when the epoxy cycloalkyl group is an epoxy cyclohexyl group) from the viewpoint of more excellent effects of the present invention. Examples of the substituent of the oxetanyl group include an alkyl group having 1 to 10 carbon atoms, and from the viewpoint of more excellent effects of the present invention, an alkyl group having 1 to 5 carbon atoms is preferred. The alkyl group as the substituent of the oxetanyl group may be linear or branched, but is preferably linear from the viewpoint of more excellent effects of the present invention. Examples of the substituent of the phenyl group include a boronic acid group, a sulfonic acid group, a vinyl group, and an amino group, and from the viewpoint of more excellent effects of the present invention, a boronic acid group is preferred.

[0128] Specific examples of the repeating unit (4) include, for example, the following structures, but the present invention is not limited thereto. In the following specific examples, n1 represents an integer of 2 or more, and n2 represents an integer of 1 or more.

[0129]

Chemical formula

[0130] The content of the repeating unit (4) is preferably 2 to 20% by mass, more preferably 3 to 18% by mass, based on the total repeating units (100% by mass) of the high molecular liquid crystal compound. If the content of the repeating unit (4) is 2% by mass or more, a light absorption anisotropic layer with excellent adhesion can be obtained. Also, if the content of the repeating unit (4) is 20% by mass or less, a light absorption anisotropic layer with excellent planar uniformity can be obtained. The repeating unit (4) may be contained alone or in two or more kinds in the high molecular liquid crystal compound. When two or more kinds of the repeating unit (4) are contained, the content of the repeating unit (4) means the total content of the repeating unit (4).

[0131] (Repeating unit (5)) From the viewpoint of planar uniformity, the high molecular liquid crystal compound can contain a repeating unit (5) introduced by polymerizing a polyfunctional monomer. In particular, in order to improve the planar uniformity while suppressing a decrease in the degree of orientation, it is preferable to contain 10% by mass or less of the repeating unit (5) introduced by polymerizing this polyfunctional monomer. The reason for being able to improve the planar uniformity while suppressing a decrease in the degree of orientation by containing 10% by mass or less of the repeating unit (5) is estimated as follows. The repeating unit (5) is a unit introduced into the high molecular liquid crystal compound by polymerizing a polyfunctional monomer. Therefore, it is considered that the high molecular liquid crystal compound contains a high molecular weight substance having a three-dimensional crosslinked structure by the repeating unit (5). Here, since the content of the repeating unit (5) is small, the content of the high molecular weight substance containing the repeating unit (5) is considered to be small. It is presumed that the slight presence of the high molecular weight substance having a three-dimensional crosslinked structure in this way suppresses the repulsion of the liquid crystal composition and a light absorption anisotropic layer with excellent planar uniformity is obtained. Also, since the content of the high molecular weight substance is small, it is presumed that the effect of suppressing a decrease in the degree of orientation can be maintained.

[0132] The repeating unit (5) introduced by polymerizing the above polyfunctional monomer is preferably a repeating unit represented by the following formula (5).

[0133]

Chemical formula

[0134] In formula (5), PC5A and PC5B represent the main chain of the repeating unit, and more specifically, represent the same structure as PC1 in the above formula (1). L5A and L5B represent a single bond or a divalent linking group, and more specifically, represent the same structure as L1 in the above formula (1). SP5A and SP5B represent spacer groups, and more specifically, represent the same structure as SP1 in the above formula (1). MG5A and MG5B represent mesogenic structures, and more specifically, represent the same structure as the mesogenic group MG in the above formula (LC). a and b represent integers of 0 or 1.

[0135] PC5A and PC5B may be the same group or different groups from each other, but are preferably the same group from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer. Both L5A and L5B may be single bonds, may be the same group, or may be different groups from each other, but are preferably both single bonds or the same group from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer, and more preferably the same group. Both SP5A and SP5B may be single bonds, may be the same group, or may be different groups from each other, but are preferably both single bonds or the same group from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer, and more preferably the same group. Here, the same group in formula (5) means that the chemical structure is the same regardless of the direction in which each group is bonded. For example, when SP5A is *-CH2-CH2-O-** (* represents the bonding position with L5A, and ** represents the bonding position with MG5A), and SP5B is *-O-CH2-CH2-** (* represents the bonding position with MG5B, and ** represents the bonding position with L5B), they are also the same group.

[0136] a and b are each independently an integer of 0 or 1, and are preferably 1 from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer. a and b may be the same or different, but are preferably both 1 from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer. The sum of a and b is preferably 1 or 2 (that is, the repeating unit represented by formula (5) has a mesogen group) from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer, and more preferably 2.

[0137] -(MG5A) a -(MG5B) b The partial structure represented by - preferably has a cyclic structure from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer. In this case, from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer, -(MG5A2) a -(MG5B) b The number of cyclic structures in the partial structure represented by - is preferably 2 or more, more preferably 2 to 8, still more preferably 2 to 6, and particularly preferably 2 to 4. The mesogen groups represented by MG5A and MG5B each independently preferably contain one or more cyclic structures, preferably 2 to 4 cyclic structures, more preferably 2 to 3 cyclic structures, and particularly preferably 2 cyclic structures from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer. Specific examples of the cyclic structure include an aromatic hydrocarbon group, a heterocyclic group, and an alicyclic group, and among these, an aromatic hydrocarbon group and an alicyclic group are preferable. MG5A and MG5B may be the same group or different groups, but are preferably the same group from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer.

[0138] As the mesogen groups represented by MG5A and MG5B, from the viewpoints of the expression of liquid crystallinity, the adjustment of the liquid crystal phase transition temperature, the availability of raw materials, and the synthetic suitability, and because the effects of the present invention are more excellent, it is preferable that they are the mesogen group MG in the above formula (LC).

[0139] In particular, for the repeating unit (5), it is preferable that PC5A and PC5B are the same group, both L5A and L5B are single bonds or the same group, both SP5A and SP5B are single bonds or the same group, and MG5A and MG5B are the same group. Thereby, the degree of orientation of the light absorption anisotropic layer is further improved.

[0140] The content of the repeating unit (5) 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 with respect to the content (100% by mass) of all the repeating units of the polymer liquid crystal compound. The repeating unit (5) may be contained alone or in two or more kinds in the polymer liquid crystal compound. When two or more kinds of repeating units (5) are contained, it is preferable that the total amount thereof is within the above range.

[0141] (Star polymer) The polymer liquid crystal compound may be a star polymer. The star polymer in the present invention means a polymer having three or more polymer chains extending from a nucleus, and specifically, it is represented by the following formula (6). The star polymer represented by the formula (6) as the polymer liquid crystal compound can form a light absorption anisotropic layer with a high degree of orientation while having high solubility (excellent solubility in a solvent).

[0142] [Chemical formula]

[0143] In formula (6), n A represents an integer of 3 or more, and an integer of 4 or more is preferable. n A The upper limit value of is not limited to this, but is usually 12 or less, and preferably 6 or less. Each of the plurality of PIs independently represents a polymer chain containing any one of the repeating units represented by the above formulas (1), (21), (22), (3), (4), and (5). However, at least one of the plurality of PIs represents a polymer chain containing the repeating unit represented by the above formula (1). A represents an atomic group that serves as the core of the star polymer. Specific examples of A include the structures obtained by removing hydrogen atoms from the thiol groups of the polyfunctional thiol compounds described in paragraphs

[0052] to

[0058] of JP-A-2011-074280, paragraphs

[0017] to

[0021] of JP-A-2012-189847, paragraphs

[0012] to

[0024] of JP-A-2013-031986, paragraphs

[0118] to

[0142] of JP-A-2014-104631, and the like. In this case, A and PI are bonded by a sulfide bond.

[0144] The number of thiol groups of the polyfunctional thiol compound from which A is derived is preferably 3 or more, more preferably 4 or more. The upper limit of the number of thiol groups of the polyfunctional thiol compound is usually 12 or less, preferably 6 or less. Specific examples of the polyfunctional thiol compound are shown below.

[0145] [Chemical formula]

[0146] From the viewpoint of improving the degree of orientation, the polymer liquid crystal compound may be a thermotropic liquid crystal and a crystalline polymer.

[0147] (Thermotropic liquid crystal) A thermotropic liquid crystal is a liquid crystal that exhibits a transition to a liquid crystal phase due to a temperature change. The polymer liquid crystal compound is a thermotropic liquid crystal and may exhibit either a nematic phase or a smectic phase. However, from the reason that haze becomes more difficult to observe (haze becomes better), it is preferable to exhibit at least a nematic phase. The temperature range showing a nematic phase is preferably from room temperature (23°C) to 450°C because the degree of orientation of the light absorption anisotropic layer becomes higher and haze becomes more difficult to observe. From the viewpoints of handling and manufacturing suitability, it is more preferably from 40°C to 400°C.

[0148] (Crystalline polymer) A crystalline polymer is a polymer that shows a transition to a crystalline layer with a change in temperature. A crystalline polymer may show a glass transition in addition to the transition to a crystalline layer. A crystalline polymer is preferably a polymer liquid crystal compound having a transition from a crystalline phase to a liquid crystal phase (there may be a glass transition in between) when heated, or a polymer liquid crystal compound having a transition to a crystalline phase (there may be a glass transition in between) when the temperature is lowered after being in a liquid crystal state by heating, because the degree of orientation of the light absorption anisotropic layer becomes higher and haze becomes more difficult to observe.

[0149] The presence or absence of crystallinity of the polymer liquid crystal compound is evaluated as follows. Two light absorption anisotropic layers of an optical microscope (ECLIPSE E600 POL manufactured by Nikon Corporation) are arranged perpendicular to each other, and a sample stage is set between the two light absorption anisotropic layers. Then, a small amount of the polymer liquid crystal compound is placed on a slide glass, and the slide glass is set on a hot stage placed on the sample stage. While observing the state of the sample, the temperature of the hot stage is raised to the temperature at which the polymer liquid crystal compound shows liquid crystallinity to make the polymer liquid crystal compound into a liquid crystal state. After the polymer liquid crystal compound becomes a liquid crystal state, the behavior of the liquid crystal phase transition is observed while gradually lowering the temperature of the hot stage, and the temperature of the liquid crystal phase transition is recorded. When the polymer liquid crystal compound shows a plurality of liquid crystal phases (for example, nematic phase and smectic phase), all of the transition temperatures are also recorded. Next, put about 5 mg of the polymer liquid crystal compound sample into an aluminum pan, cover it, and set it in a differential scanning calorimeter (DSC) (using an empty aluminum pan as a reference). Heat it up to the temperature at which the polymer liquid crystal compound measured above exhibits a liquid crystal phase, and then hold the temperature for 1 minute. Then, while cooling at a rate of 10 °C / min, perform heat quantity measurement. Confirm an exothermic peak from the obtained heat quantity spectrum. As a result, when an exothermic peak is observed at a temperature other than the temperature of the liquid crystal phase transition, it can be said that the exothermic peak is due to crystallization and the polymer liquid crystal compound has crystallinity. On the other hand, when no exothermic peak is observed at a temperature other than the temperature of the liquid crystal phase transition, it can be said that the polymer liquid crystal compound does not have crystallinity.

[0150] The method for obtaining the crystalline polymer is not particularly limited. As a specific example, a method using a polymer liquid crystal compound containing the above repeating unit (1) is preferable, and among them, a method using a preferred embodiment in the polymer liquid crystal compound containing the above repeating unit (1) is more preferable.

[0151] ·Crystallization temperature The crystallization temperature of the polymer liquid crystal compound is preferably -50 °C or higher and less than 150 °C, more preferably 120 °C or lower, still more preferably -20 °C or higher and less than 120 °C, and particularly preferably 95 °C or lower, because the degree of orientation of the photoabsorption anisotropic layer becomes higher and haze becomes more difficult to observe. From the viewpoint of reducing haze, the crystallization temperature of the above polymer liquid crystal compound is preferably less than 150 °C. Note that the crystallization temperature is the temperature of the exothermic peak due to crystallization in the above-described DSC.

[0152] (Molecular weight) The weight average molecular weight (Mw) of the polymer liquid crystal compound is preferably 1000 to 500000, more preferably 2000 to 300000, from the viewpoint that the effects of the present invention are more excellent. If the Mw of the polymer liquid crystal compound is within the above range, the handling of the polymer liquid crystal compound becomes easy. In particular, from the perspective of suppressing cracks during coating, the weight average molecular weight (Mw) of the polymer liquid crystal compound is preferably 10,000 or more, more preferably 10,000 to 300,000. Also, from the perspective of the temperature latitude of the degree of orientation, the weight average molecular weight (Mw) of the polymer liquid crystal compound is preferably less than 10,000, more preferably 2,000 or more and less than 10,000. Here, the weight average molecular weight and the number average molecular weight in the present invention are values measured by the gel permeation chromatography (GPC) method. · Solvent (eluent): N-methylpyrrolidone · Apparatus name: TOSOH HLC-8220GPC · Column: Three TOSOH TSKgel Super AWM-H (6 mm × 15 cm) columns are connected and used. · Column temperature: 25 °C · Sample concentration: 0.1 mass% · Flow rate: 0.35 mL / min · Calibration curve: A calibration curve using 7 samples of TOSOH-made TSK standard polystyrene with Mw = 2,800,000 to 1,050 (Mw / Mn = 1.03 to 1.06) is used.

[0153] The liquid crystallinity of the polymer liquid crystal compound may exhibit either a nematic phase or a smectic phase, but it is preferably at least a nematic phase. The temperature range showing the nematic phase is preferably 0 °C to 450 °C, and from the perspective of handling and manufacturing suitability, it is preferably 30 °C to 400 °C.

[0154] The content of the liquid crystal compound is preferably 25 to 2,000 parts by mass, more preferably 100 to 1,300 parts by mass, and even more preferably 200 to 900 parts by mass with respect to 100 parts by mass of the content of the dichroic substance in the liquid crystal composition. When the content of the liquid crystal compound is within the above range, the degree of orientation of the polarizer is further improved. The liquid crystal compound may be contained alone or in two or more kinds. When two or more kinds of liquid crystal compounds are contained, the content of the above liquid crystal compound means the total content of the liquid crystal compounds.

[0155] [Dichroic substance] The light absorption anisotropic layer used in the present invention contains an organic dichroic substance. The organic dichroic substance is not particularly limited, and examples include visible light absorbing substances (dichroic substances, dichroic azo compounds), luminescent substances (fluorescent substances, phosphorescent substances), ultraviolet absorbing substances, infrared absorbing substances, nonlinear optical substances, carbon nanotubes, inorganic substances (e.g., quantum rods), etc. Conventionally known organic dichroic substances (dichroic dyes, dichroic pigments) can be used.

[0156] The preferably used dichroic substance is an organic dichroic substance, and particularly preferably a dichroic azo dye compound. The dichroic azo dye compound is not particularly limited, and conventionally known dichroic azo dyes can be used, but the compounds described later are preferably used.

[0157] In the present invention, the dichroic azo dye compound means a dye having different absorbances depending on the direction. The dichroic azo dye compound may or may not exhibit liquid crystallinity. When the dichroic azo dye compound exhibits liquid crystallinity, it may exhibit either a nematic phase or a smectic phase. The temperature range showing the liquid crystal phase is preferably from room temperature (about 20°C to 28°C) to 300°C, and more preferably from 50°C to 200°C from the viewpoints of handleability and manufacturing suitability.

[0158] Specifically, in the present invention, from the viewpoint of color tone adjustment, the light absorption anisotropic layer preferably has at least one dye compound having a maximum absorption wavelength in the range of 560 to 700 nm (hereinafter also abbreviated as "first dichroic azo dye compound"), and at least one dye compound having a maximum absorption wavelength in the range of 455 nm or more and less than 560 nm (hereinafter also abbreviated as "second dichroic azo dye compound"), and more preferably specifically has at least the dichroic azo dye compound represented by the formula (1) described later and the dichroic azo dye compound represented by the formula (2) described later.

[0159] In the present invention, three or more dichroic azo dye compounds may be used in combination. For example, from the viewpoint of making the light absorption anisotropic layer approach black, a first dichroic azo dye compound, a second dichroic azo dye compound, and at least one dye compound having a maximum absorption wavelength in the range of 380 nm or more and less than 455 nm (hereinafter, also abbreviated as "third dichroic azo dye compound") are preferably used in combination. That is, in the present invention, the light absorption anisotropic layer preferably contains two or more organic dichroic substances having different absorption peak wavelengths, and more preferably contains three or more organic dichroic substances having different absorption peak wavelengths.

[0160] In the present invention, from the viewpoint of better pressure resistance, it is preferable that the dichroic azo dye compound has a crosslinkable group. Specific examples of the crosslinkable group include, for example, (meth)acryloyl group, epoxy group, oxetanyl group, styryl group, etc. Among them, (meth)acryloyl group is preferable.

[0161] (First dichroic azo dye compound) The first dichroic azo dye compound is preferably a compound having a chromophore as a nucleus and a side chain bonded to the end of the chromophore. Specific examples of the chromophore include aromatic ring groups (for example, aromatic hydrocarbon groups, aromatic heterocyclic groups), azo groups, etc. A structure having both an aromatic ring group and an azo group is preferable, and a bisazo structure having an aromatic heterocyclic group (preferably a thienothiazole group) and two azo groups is more preferable. The side chain is not particularly limited, and examples include groups represented by L3, R2 or L4 in the following formula (1).

[0162] The first dichroic azo dye compound is a dichroic azo dye compound having a maximum absorption wavelength in the range of 560 nm or more and 700 nm or less. From the viewpoint of adjusting the color tone of the polarizer, it is preferably a dichroic azo dye compound having a maximum absorption wavelength in the range of 560 to 650 nm, and more preferably a dichroic azo dye compound having a maximum absorption wavelength in the range of 560 to 640 nm. The maximum absorption wavelength (nm) of the dichroic azo dye compound in this specification is determined from the ultraviolet-visible light spectrum in the wavelength range of 380 to 800 nm measured by a spectrophotometer using a solution in which the dichroic azo dye compound is dissolved in a good solvent.

[0163] In the present invention, for the reason that the degree of orientation of the formed light absorption anisotropic layer is further improved, the first dichroic azo dye compound is preferably a compound represented by the following formula (1).

[0164] [Chemical formula]

[0165] In formula (1), Ar1 and Ar2 each independently represent a phenylene group which may have a substituent, or a naphthylene group which may have a substituent, and a phenylene group is preferred.

[0166] In formula (1), R1 represents a hydrogen atom, a linear or branched alkyl group which may have a substituent having 1 to 20 carbon atoms, an alkoxy group, an alkylthio group, an alkylsulfonyl group, an alkylcarbonyl group, an alkyloxycarbonyl group, an acyloxy group, an alkyl carbonate group, an alkylamino group, an acylamino group, an alkylcarbonylamino group, an alkoxycarbonylamino group, an alkylsulfonylamino group, an alkylsulfamoyl group, an alkylcarbamoyl group, an alkylsulfinyl group, an alkylureido group, an alkylphosphoric amide group, an alkylimino group, or an alkylsilyl group. -CH2- constituting the above alkyl group may be substituted by -O-, -CO-, -C(O)-O-, -O-C(O)-, -Si(CH3)2-O-Si(CH3)2-, -N(R1’)-, -N(R1’)-CO-, -CO-N(R1’)-, -N(R1’)-C(O)-O-, -O-C(O)-N(R1’)-, -N(R1’)-C(O)-N(R1’)-, -CH=CH-, -C≡C-, -N=N-, -C(R1’)=CH-C(O)-, or -O-C(O)-O-. When R1 is a group other than a hydrogen atom, the hydrogen atoms possessed by each group may be substituted by a halogen atom, a nitro group, a cyano group, -N(R1’)2, an amino group, -C(R1’)=C(R1’)-NO2, -C(R1’)=C(R1’)-CN, or -C(R1’)=C(CN)2. R1’ represents a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms. In each group, when there are a plurality of R1’, they may be the same as or different from each other.

[0167] In formula (1), R2 and R3 each independently represent a hydrogen atom, a linear or branched alkyl group which may have a substituent having 1 to 20 carbon atoms, an alkoxy group, an acyl group, an alkyloxycarbonyl group, an alkylamide group, an alkylsulfonyl group, an aryl group, an arylcarbonyl group, an arylsulfonyl group, an aryloxycarbonyl group, or an arylamide group. -CH2- constituting the above alkyl group may be substituted by -O-, -S-, -C(O)-, -C(O)-O-, -O-C(O)-, -C(O)-S-, -S-C(O)-, -Si(CH3)2-O-Si(CH3)2-, -NR2’-, -NR2’-CO-, -CO-NR2’-, -NR2’-C(O)-O-, -O-C(O)-NR2’-, -NR2’-C(O)-NR2’-, -CH=CH-, -C≡C-, -N=N-, -C(R2’)=CH-C(O)-, or -O-C(O)-O-. When R2 and R3 are groups other than a hydrogen atom, the hydrogen atoms possessed by each group may be substituted by a halogen atom, a nitro group, a cyano group, an -OH group, -N(R2’)2, an amino group, -C(R2’)=C(R2’)-NO2, -C(R2’)=C(R2’)-CN, or -C(R2’)=C(CN)2. R2’ represents a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms. In each group, when there are a plurality of R2’, they may be the same as or different from each other. R2 and R3 may combine with each other to form a ring, or R2 or R3 may combine with Ar2 to form a ring.

[0168] From the viewpoint of light resistance, R1 is preferably an electron-withdrawing group, and R2 and R3 are preferably groups with low electron-donating properties. Specific examples of such groups include, as R1, an alkylsulfonyl group, an alkylcarbonyl group, an alkyloxycarbonyl group, an acyloxy group, an alkylsulfonylamino group, an alkylsulfamoyl group, an alkylsulfinyl group, and an alkylureido group, etc. Examples of R2 and R3 include groups having the following structures. The groups having the following structures are shown in a form including the nitrogen atom to which R2 and R3 are bonded in the above formula (1).

[0169]

Chemical formula

[0170] Specific examples of the first dichroic azo dye compound are shown below, but are not limited thereto.

[0171]

Chemical formula

[0172] (The second dichroic azo dye compound) The second dichroic azo dye compound is a compound different from the first dichroic azo dye compound, specifically, its chemical structure is different. The second dichroic azo dye compound preferably has a chromophore that is the nucleus of the dichroic azo dye compound and a side chain bonded to the end of the chromophore. Specific examples of the chromophore include an aromatic ring group (e.g., an aromatic hydrocarbon group, an aromatic heterocyclic group), an azo group, etc. A structure having both an aromatic hydrocarbon group and an azo group is preferred, and a bisazo or trisazo structure having an aromatic hydrocarbon group and two or three azo groups is more preferred. The side chain is not particularly limited, and examples thereof include groups represented by R4, R5, or R6 in formula (2) described below.

[0173] The second dichroic azo dye compound is a dichroic azo dye compound having a maximum absorption wavelength in the range of 455 nm or more and less than 560 nm. From the viewpoint of adjusting the color tone of the polarizer, it is preferably a dichroic azo dye compound having a maximum absorption wavelength in the range of 455 to 555 nm, and more preferably a dichroic azo dye compound having a maximum absorption wavelength in the range of 455 to 550 nm. In particular, by using a first dichroic azo dye compound having a maximum absorption wavelength of 560 to 700 nm and a second dichroic azo dye compound having a maximum absorption wavelength of 455 nm or more and less than 560 nm, it becomes easier to adjust the color tone of the polarizer.

[0174] The second dichroic azo dye compound is preferably a compound represented by formula (2) from the viewpoint of further improving the degree of orientation of the polarizer.

[0175]

Chemical formula

[0176] In formula (2), n represents 1 or 2. In formula (2), Ar3, Ar4, and Ar5 each independently represent a phenylene group which may have a substituent, a naphthylene group which may have a substituent, or a heterocyclic group which may have a substituent. The heterocyclic group may be either aromatic or non-aromatic. Examples of atoms other than carbon constituting the aromatic heterocyclic group include a nitrogen atom, a sulfur atom, and an oxygen atom. When the aromatic heterocyclic group has a plurality of atoms other than carbon constituting the ring, these may be the same or different. Specific examples of the aromatic heterocyclic group include, for example, a pyridylene group (pyridine-diyl group), a pyridazine-diyl group, an imidazole-diyl group, a thienylene (thiophene-diyl group), a quinolyrene group (quinoline-diyl group), an isoquinolyrene group (isoquinoline-diyl group), an oxazole-diyl group, a thiazole-diyl group, an oxadiazole-diyl group, a benzothiazole-diyl group, a benzothiadiazole-diyl group, a phthalimide-diyl group, a thienothiazole-diyl group, a thiazolothiazole-diyl group, a thienothiophene-diyl group, and a thienooxazole-diyl group.

[0177] In formula (2), the definition of R4 is the same as that of R1 in formula (1). In formula (2), the definitions of R5 and R6 are the same as those of R2 and R3 in formula (1), respectively.

[0178] From the viewpoint of light resistance, R4 is preferably an electron-withdrawing group, and R5 and R6 are preferably groups with low electron-donating properties. Among such groups, specific examples when R4 is an electron-withdrawing group are the same as the specific examples when R1 is an electron-withdrawing group, and specific examples when R5 and R6 are groups with low electron-donating properties are the same as the specific examples when R2 and R3 are groups with low electron-donating properties.

[0179] Specific examples of the second dichroic azo dye compound are shown below, but are not limited thereto.

[0180]

Chemical formula

[0181] (Difference in logP value) The logP value is an index representing the hydrophilic and hydrophobic properties of a 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, still 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 increases, making it easier to form a sequence structure, and thus the degree of orientation of the light absorption anisotropic layer is further improved. In the case where there are a plurality of side chains in the first dichroic azo dye compound or the second dichroic azo dye compound, it is preferable that at least one logP difference satisfies the above value. Here, the side chains of the first dichroic azo dye compound and the second dichroic azo dye compound mean groups bonded to the ends of the above-described chromophores. For example, when the first dichroic azo dye compound is a compound represented by formula (1), R1, R2, and R3 in formula (1) are side chains, and when the second dichroic azo dye 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 dye compound is a compound represented by formula (1) and the second dichroic azo dye compound is a compound represented by formula (2), among the differences in logP values between R1 and R4, R1 and R5, R2 and R4, and R2 and R5, it is preferable that at least one logP difference satisfies the above value.

[0182] Here, the logP value is an index representing the hydrophilic and hydrophobic properties of a chemical structure and is sometimes called the hydrophilic-lipophilic 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 by methods such as those described in OECD Guidelines for the Testing of Chemicals, Sections 1, Test No. 117. In the present invention, unless otherwise specified, the value calculated by inputting the structural formula of the compound into HSPiP (Ver. 4.1.07) is adopted as the logP value.

[0183] (Third dichroic azo dye compound) The third dichroic azo dye compound is a dichroic azo dye compound other than the first dichroic azo dye compound and the second dichroic azo dye compound. Specifically, it has a chemical structure different from that of the first dichroic azo dye compound and the second dichroic azo dye compound. If the composition for forming the light absorption anisotropic layer contains the third dichroic azo dye compound, there is an advantage that the color tone of the light absorption anisotropic layer can be easily adjusted. The maximum absorption wavelength of the third dichroic azo dye compound is 380 nm or more and less than 455 nm, and preferably 385 - 454 nm.

[0184] The third dichroic azo dye compound preferably contains a dichroic azo dye represented by the following formula (6).

[0185] [Chemical formula]

[0186] In formula (6), A and B each independently represent a crosslinkable group. In formula (6), a and b each independently represent 0 or 1. In terms of excellent alignment degree at 420 nm, it is preferable that both a and b are 0. In formula (6), when a = 0, L1 represents a monovalent substituent; when a = 1, L1 represents a single bond or a divalent linking group. Further, when b = 0, L2 represents a monovalent substituent; when b = 1, L2 represents a single bond or a divalent linking group. In formula (6), Ar1 represents an (n1 + 2)-valent aromatic hydrocarbon group or a heterocyclic group, Ar2 represents an (n2 + 2)-valent aromatic hydrocarbon group or a heterocyclic group, and Ar3 represents an (n3 + 2)-valent aromatic hydrocarbon group or a heterocyclic group. In formula (6), R1, R2, and R3 each independently represent a monovalent substituent. When n1 ≥ 2, a plurality of R1s may be the same as or different from each other; when n2 ≥ 2, a plurality of R2s may be the same as or different from each other; when n3 ≥ 2, a plurality of R3s may be the same as or different from each other. In formula (6), k represents an integer from 1 to 4. When k ≥ 2, a plurality of Ar2s may be the same as or different from each other, and a plurality of R2s may be the same as or different from each other. In formula (6), n1, n2, and n3 each independently represent an integer from 0 to 4. However, when k = 1, n1 + n2 + n3 ≥ 0; when k ≥ 2, n1 + n2 + n3 ≥ 1.

[0187] In formula (6), examples of the crosslinkable groups represented by A and B include the polymerizable groups described in paragraphs

[0040] to

[0050] of JP-A-2010-244038. Among these, from the viewpoints of improving reactivity and synthesis suitability, an acryloyl group, a methacryloyl group, an epoxy group, an oxetanyl group, and a styryl group are preferable, and from the viewpoint of further improving solubility, an acryloyl group and a methacryloyl group are more preferable.

[0188] In formula (6), when a = 0, L1 represents a monovalent substituent; when a = 1, L1 represents a single bond or a divalent linking group. Further, when b = 0, L2 represents a monovalent substituent; when b = 1, L2 represents a single bond or a divalent linking group.

[0189] As the monovalent substituents represented by L1 and L2, groups introduced to enhance the solubility of the dichroic substance or groups having electron-donating or electron-withdrawing properties introduced to adjust the color tone as a dye are preferred. For example, as the substituents, an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, for example, methyl group, ethyl group, isopropyl group, tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, etc.), an alkenyl group (preferably an alkenyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, for example, vinyl group, allyl group, 2-butenyl group, 3-pentenyl group, etc.), an alkynyl group (preferably an alkynyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, for example, propargyl group, 3-pentynyl group, etc.), an aryl group (preferably an aryl group having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms, for example, phenyl group, 2,6-diethylphenyl group, 3,5-ditrifluoromethylphenyl group, naphthyl group, and biphenyl group, etc.), a substituted or unsubstituted amino group (preferably an amino group having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, particularly preferably 0 to 6 carbon atoms, for example, unsubstituted amino group, methylamino group, dimethylamino group, diethylamino group, anilino group, etc.), an alkoxy group (preferably having 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, for example, methoxy group, ethoxy group, butoxy group, etc.), an oxycarbonyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 15 carbon atoms, particularly preferably 2 to 10 carbon atoms, for example, methoxycarbonyl group, ethoxycarbonyl group, phenoxycarbonyl group, etc.), An acyloxy group (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, and examples thereof include an acetoxy group and a benzoyloxy group), An acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, and examples thereof include an acetylamino group and a benzoylamino group), An alkoxycarbonylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms, particularly preferably 2 to 6 carbon atoms, and examples thereof include a methoxycarbonylamino group), An aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms, and examples thereof include a phenyloxycarbonylamino group), A sulfonylamino group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include a methanesulfonylamino group and a benzenesulfonylamino group), A sulfamoyl group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, particularly preferably 0 to 6 carbon atoms, and examples thereof include a sulfamoyl group, a methylsulfamoyl group, a dimethylsulfamoyl group, and a phenylsulfamoyl group), A carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include an unsubstituted carbamoyl group, a methylcarbamoyl group, a diethylcarbamoyl group, and a phenylcarbamoyl group), An alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include a methylthio group and an ethylthio group), An arylthio group (preferably having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, and examples thereof include a phenylthio group), A sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include a mesyl group, a tosyl group, etc.), A sulfinyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include a methanesulfinyl group, a benzenesulfinyl group, etc.), A ureido group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include an unsubstituted ureido group, a methylureido group, a phenylureido group, etc.), A phosphoric acid amide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, particularly preferably 1 to 6 carbon atoms, and examples thereof include a diethylphosphoric acid amide group, a phenylphosphoric acid amide group, etc.), A heterocyclic group (preferably a heterocyclic group having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms, and examples thereof include a heterocyclic group having a heteroatom such as a nitrogen atom, an oxygen atom, a sulfur atom, etc., and examples thereof include an imidazolyl group, a pyridyl group, a quinolyl group, a furyl group, a piperidyl group, a morpholino group, a benzoxazolyl group, a benzimidazolyl group, a benzothiazolyl group, etc.), A silyl group (preferably a silyl group having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms, and examples thereof include a trimethylsilyl group, a triphenylsilyl group, etc.), A halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), A hydroxy group, a mercapto group, a cyano group, a nitro group, a hydroxamic acid group, a sulfino group, a hydrazino group, an imino group, and an azo group, etc. can be used. These substituents may be further substituted by these substituents. Also, when having two or more substituents, they may be the same or different. Also, if possible, they may be bonded to each other to form a ring. Examples of the group in which the above substituent is further substituted by the above substituent include a group in which an alkoxy group is substituted by an alkyl group, R B -(O-RA ) na include - groups. Here, in the formula, R A represents an alkylene group having 1 to 5 carbon atoms, R B represents an alkyl group having 1 to 5 carbon atoms, and na represents an integer of 1 to 10 (preferably 1 to 5, more preferably 1 to 3). Among these, as the monovalent substituents represented by L1 and L2, an alkyl group, an alkenyl group, an alkoxy group, and a group in which these groups are further substituted by these groups (for example, the above-mentioned R B -(O-R A ) na - group) are preferred, and an alkyl group, an alkoxy group, and a group in which these groups are further substituted by these groups (for example, the above-mentioned R B -(O-R A ) na - group) are more preferred.

[0190] Examples of the divalent linking groups represented by L1 and L2 include -O-, -S-, -CO-, -COO-, -OCO-, -O-CO-O-, -CO-NR N -, -O-CO-NR N -, -NR N -CO-NR N -, -SO2-, -SO-, an alkylene group, a cycloalkylene group, an alkenylene group, and a group formed by combining two or more of these groups, etc. Among these, a group formed by combining an alkylene group and one or more groups selected from the group consisting of -O-, -COO-, -OCO- and -O-CO-O- is preferred. Here, R N represents a hydrogen atom or an alkyl group. When there are a plurality of R N , the plurality of R N may be the same as or different from each other.

[0191] From the viewpoint of further improving the solubility of the dichroic substance, the number of atoms in the main chain of at least one of L1 and L2 is preferably 3 or more, more preferably 5 or more, still more preferably 7 or more, and particularly preferably 10 or more. Further, the upper limit of the number of atoms in the main chain is preferably 20 or less, more preferably 12 or less. On the other hand, from the viewpoint of further improving the degree of orientation of the light absorption anisotropic layer, the number of atoms in the main chain of at least one of L1 and L2 is preferably 1 to 5. Here, when A in the formula (6) is present, the "main chain" in L1 refers to the portion necessary for directly connecting the "O" atom connected to L1 and "A", and the "number of atoms in the main chain" refers to the number of atoms constituting the above portion. Similarly, when B in the formula (6) is present, the "main chain" in L2 refers to the portion necessary for directly connecting the "O" atom connected to L2 and "B", and the "number of atoms in the main chain" refers to the number of atoms constituting the above portion. Note that the "number of atoms in the main chain" does not include the number of atoms in the branched chain described later. When A is not present, the "number of atoms in the main chain" in L1 refers to the number of atoms in L1 that does not include the branched chain. When B is not present, the "number of atoms in the main chain" in L2 refers to the number of atoms in L2 that does not include the branched chain. Specifically, in the following formula (D1), the number of atoms in the main chain of L1 is 5 (the number of atoms within the left dotted frame in the following formula (D1)), and the number of atoms in the main chain of L2 is 5 (the number of atoms within the right dotted frame in the following formula (D1)). Further, in the following formula (D10), the number of atoms in the main chain of L1 is 7 (the number of atoms within the left dotted frame in the following formula (D10)), and the number of atoms in the main chain of L2 is 5 (the number of atoms within the right dotted frame in the following formula (D10)).

[0192]

Chemical formula

[0193] L1 and L2 may have a branched chain. Here, when A exists in formula (6), the "branched chain" in L1 refers to the part other than the part necessary for directly connecting the "O" atom connected to L1 in formula (6) and "A". Similarly, when B exists in formula (6), the "branched chain" in L2 refers to the part other than the part necessary for directly connecting the "O" atom connected to L2 in formula (6) and "B". Also, when A does not exist in formula (6), the "branched chain" in L1 refers to the part other than the longest atomic chain (i.e., the main chain) extending from the "O" atom connected to L1 in formula (6). Similarly, when B does not exist in formula (6), the "branched chain" in L2 refers to the part other than the longest atomic chain (i.e., the main chain) extending from the "O" atom connected to L2 in formula (6). The number of atoms in the branched chain is preferably 3 or less. When the number of atoms in the branched chain is 3 or less, there are advantages such as the orientation degree of the light absorption anisotropic layer being further improved. Note that the number of atoms in the branched chain does not include the number of hydrogen atoms.

[0194] In formula (6), Ar1 represents an aromatic hydrocarbon group or a heterocyclic group having (n1 + 2) valences (for example, trivalent when n1 is 1), Ar2 represents an aromatic hydrocarbon group or a heterocyclic group having (n2 + 2) valences (for example, trivalent when n2 is 1), and Ar3 represents an aromatic hydrocarbon group or a heterocyclic group having (n3 + 2) valences (for example, trivalent when n3 is 1). Here, Ar1 to Ar3 can be paraphrased as divalent aromatic hydrocarbon groups or divalent heterocyclic groups substituted with n1 to n3 substituents (R1 to R3 described later), respectively. As the divalent aromatic hydrocarbon group represented by Ar1 to Ar3, it may be monocyclic or may have a condensed ring structure of two or more rings. From the viewpoint of further improving solubility, the number of rings of the divalent aromatic hydrocarbon group is preferably 1 to 4, more preferably 1 to 2, and even more preferably 1 (i.e., being a phenylene group). Specific examples of the divalent aromatic hydrocarbon group include a phenylene group, an azulene-diyl group, a naphthylene group, a fluorene-diyl group, an anthracene-diyl group, and a tetracene-diyl group. From the viewpoint of further improving solubility, a phenylene group and a naphthylene group are preferable, and a phenylene group is more preferable. Specific examples of the third dichroic substance compound are shown below, but the present invention is not limited thereto. In the following specific examples, n represents an integer of 1 to 10.

[0195]

Chemical formula

[0196]

Chemical formula

[0197] In terms of excellent alignment degree at 420 nm, the third dye preferably has a structure without a radical polymerizable group. For example, the following structures can be mentioned.

[0198]

Chemical formula

[0199] The third dichroic azo dye compound is more preferably a dichroic substance having a structure represented by the following formula (1-1) in terms of particularly excellent alignment degree at 420 nm.

[0200]

Chemical formula

[0201] In formula (1-1), the definitions of R1, R3, R4, R5, n1, n3, L1 and L2 are the same as those of R1, R3, R4, R5, n1, n3, L1 and L2 in formula (1), respectively. In formula (1-1), R 21and R 22 The definitions of 22 are each independently synonymous with R2 in Formula (1). In Formula (1-1), the definitions of n21 and n22 are each independently synonymous with n2 in Formula (1). n1 + n21 + n22 + n3 ≥ 1, and n1 + n21 + n22 + n3 is preferably from 1 to 9, more preferably from 1 to 5.

[0202] Specific examples of the specific dichroic substance are shown below, but the present invention is not limited thereto.

[0203] [Chemical formula]

[0204] [Chemical formula]

[0205] [Chemical formula]

[0206] (Content of dichroic substance) The content of the dichroic substance is preferably 5 to 30% by mass, more preferably 15 to 28% by mass, and even more preferably 20 to 30% by mass based on the total solid mass of the light absorption anisotropic layer. If the content of the dichroic substance is within the above range, a highly oriented light absorption anisotropic layer can be obtained even when the light absorption anisotropic layer is formed into a thin film. Therefore, a light absorption anisotropic layer excellent in flexibility is easily obtained. Further, when it exceeds 30% by mass, it becomes difficult to suppress internal reflection due to an increase in refractive index. From the viewpoint of increasing the contrast between the illuminance at the center of the viewing angle and the illuminance in a direction deviated from the center of the viewing angle, the content per unit area of the dichroic substance is preferably 0.2 g / m 2 or more, more preferably 0.3 g / m 2 or more, and even more preferably 0.5 g / m 2 or more. There is no particular upper limit, but it is usually 1.0 g / m 2It is often used below. The content of the first dichroic azo dye compound is preferably 40 to 90 parts by mass, more preferably 45 to 75 parts by mass, with respect to 100 parts by mass of the total content of the dichroic substances in the composition for forming the light absorption anisotropic layer. The content of the second dichroic azo dye compound is preferably 6 to 50 parts by mass, more preferably 8 to 35 parts by mass, with respect to 100 parts by mass of the total content of the dichroic substances in the composition for forming the light absorption anisotropic layer. The content of the third dichroic azo dye compound is preferably 3 to 35 parts by mass, more preferably 5 to 30 parts by mass, with respect to 100 parts by mass of the content of the dichroic azo dye compound in the composition for forming the light absorption anisotropic layer. The content ratios of the first dichroic azo dye compound, the second dichroic azo dye compound, and, if necessary, the third dichroic azo dye compound can be arbitrarily set in order to adjust the color tone of the light absorption anisotropic layer. 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, more preferably 0.2 to 5, and particularly preferably 0.3 to 0.8 in terms of molar conversion. If the content ratio of the second dichroic azo dye compound to the first dichroic azo dye compound is within the above range, the degree of orientation can be increased.

[0207] The light absorption anisotropic layer in the present invention can be produced, for example, using a composition for forming a light absorption anisotropic layer containing the above-described liquid crystal compound and organic dichroic substance. The composition for forming the light absorption anisotropic layer may contain components other than the liquid crystal compound and the organic dichroic substance. Examples of components other than the liquid crystal compound and the organic dichroic substance include a solvent, a vertical alignment agent, a polymerizable component, a polymerization initiator (e.g., a radical polymerization initiator), and a leveling agent, etc. In this case, the light absorption anisotropic layer in the present invention contains solid components other than liquid components (such as a solvent).

[0208] (Polymerizable component) Examples of the polymerizable component include compounds containing acrylate (e.g., acrylate monomers). In this case, the light absorption anisotropic layer in the present invention contains polyacrylate obtained by polymerizing the compound containing acrylate. Examples of the polymerizable component include, for example, the compounds described in paragraph 0058 of JP-A-2017-122776. When the composition for forming a light absorption anisotropic layer contains a polymerizable component, the content of the polymerizable component is preferably 3 to 20 parts by mass with respect to a total of 100 parts by mass of the organic dichroic substance and the liquid crystal compound in the composition for forming a light absorption anisotropic layer.

[0209] (Vertical alignment agent) The composition for forming a light absorption anisotropic layer may optionally contain a vertical alignment agent. Examples of the vertical alignment agent include boronic acid compounds and onium salts.

[0210] As the boronic acid compound, a compound represented by formula (30) is preferred.

[0211] Formula (30)

[0212] [Chemical formula]

[0213] In formula (30), R 1 and R 2 each independently represent a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. R 3 represents a substituent containing a (meth)acrylic group. Specific examples of the boronic acid compound include the boronic acid compounds represented by general formula (I) described in paragraphs 0023 to 0032 of JP-A-2008-225281. As the boronic acid compound, the following exemplified compounds are also preferred.

[0214] [Chemical formula]

[0215] As the onium salt, the compound represented by the formula (31) is preferable.

[0216] Formula (31)

[0217] [Chemical formula]

[0218] In formula (31), ring A represents a quaternary ammonium ion composed of a nitrogen-containing heterocyclic ring. X represents an anion. L 1 represents a divalent linking group. L 2 represents a single bond or a divalent linking group. Y 1 represents a divalent linking group having a 5- or 6-membered ring as a partial structure. Z represents a divalent linking group having an alkylene group of 2 to 20 as a partial structure. P 1 and P 2 each independently represents a monovalent substituent having a polymerizable ethylenic unsaturated bond. Specific examples of the onium salt include the onium salts described in paragraphs 0052 to 0058 of JP-A-2012-208397, the onium salts described in paragraphs 0024 to 0055 of JP-A-2008-026730, and the onium salts described in JP-A-2002-37777.

[0219] The content of the vertical alignment agent in the composition is preferably 0.1 to 400% by mass, more preferably 0.5 to 350% by mass, based on the total mass of the liquid crystal compound. The vertical alignment agent may be used alone or in combination of two or more. When two or more vertical alignment agents are used, the total amount thereof is preferably within the above range.

[0220] (Leveling agent) The composition for forming the light absorption anisotropic layer preferably contains the following leveling agent. When the composition contains the leveling agent, planar roughness due to the drying wind applied to the surface of the light absorption anisotropic layer is suppressed, and in the light absorption anisotropic layer, the organic dichroic substance is more uniformly oriented. The leveling agent can also be used as a so-called surfactant. The leveling agent is not particularly limited, and a leveling agent containing a fluorine atom (fluorine-based leveling agent) or a leveling agent containing a silicon atom (silicon-based leveling agent) is preferable, and a fluorine-based leveling agent is more preferable.

[0221] Examples of the fluorine-based leveling agent include fatty acid esters of polyvalent carboxylic acids in which a part of the fatty acid is substituted with a fluoroalkyl group, and polyacrylates having a fluoro substituent. In particular, when a rod-shaped compound is used as the dichroic substance and the liquid crystal compound, a leveling agent containing a repeating unit derived from the compound represented by the formula (40) is preferable from the viewpoint of promoting the vertical alignment of the dichroic substance and the liquid crystal compound.

[0222] Formula (40)

[0223]

Chemical formula

[0224] R 0 represents a hydrogen atom, a halogen atom, or a methyl group. L represents a divalent linking group. As L, an alkylene group having 2 to 16 carbon atoms is preferable, and any non-adjacent -CH2- in the alkylene group may be substituted with -O-, -COO-, -CO-, or -CONH-. n represents an integer of 1 to 18.

[0225] The leveling agent having a repeating unit derived from the compound represented by the formula (40) may further contain other repeating units. Examples of the other repeating units include repeating units derived from the compound represented by the formula (41).

[0226] Formula (41)

[0227]

Chem.

[0228] R 11 represents a hydrogen atom, a halogen atom, or a methyl group. X represents an oxygen atom, a sulfur atom, or -N(R 13 ). R 13 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R 12 represents a hydrogen atom, an alkyl group which may have a substituent, or an aromatic group which may have a substituent. The number of carbon atoms of the above alkyl group is preferably 1 to 20. The above alkyl group may be linear, branched, or cyclic. In addition, examples of the substituent which the above alkyl group may have include a poly(alkyleneoxy) group and a polymerizable group. The definition of the polymerizable group is as described above.

[0229] When the leveling agent contains a repeating unit derived from the compound represented by Formula (40) and a repeating unit derived from the compound represented by Formula (41), the content of the repeating unit derived from the compound represented by Formula (40) is preferably 10 to 90 mol%, more preferably 15 to 95 mol%, based on all the repeating units contained in the leveling agent. When the leveling agent contains a repeating unit derived from the compound represented by Formula (40) and a repeating unit derived from the compound represented by Formula (41), the content of the repeating unit derived from the compound represented by Formula (41) is preferably 10 to 90 mol%, more preferably 5 to 85 mol%, based on all the repeating units contained in the leveling agent.

[0230] In addition, examples of the leveling agent include a leveling agent containing a repeating unit derived from the compound represented by Formula (42) in place of the repeating unit derived from the compound represented by Formula (40) described above.

[0231] Formula (42)

[0232] [Chem.]

[0233] R 2 represents a hydrogen atom, a halogen atom, or a methyl group. L 2 represents a divalent linking group. n represents an integer from 1 to 18.

[0234] Specific examples of the leveling agent include the compounds exemplified in paragraphs 0046 to 0052 of JP-A-2004-331812 and the compounds described in paragraphs 0038 to 0052 of JP-A-2008-257205.

[0235] The content of the leveling agent in the composition is preferably 0.001 to 10% by mass, more preferably 0.01 to 5% by mass, based on the total mass of the liquid crystal compound. The leveling agent may be used alone or in combination of two or more. When two or more leveling agents are used, the total amount thereof is preferably within the above range.

[0236] (Polymerization initiator) The composition for forming a photoabsorptive anisotropic layer preferably contains a polymerization initiator. The polymerization initiator is not particularly limited, but is preferably a compound having photosensitivity, that is, a photopolymerization initiator. As the photoinitiator, various compounds can be used without particular limitation. Examples of photoinitiators include α-carbonyl compounds (specifications of U.S. Patent Nos. 2,367,661 and 2,367,670), acyloin ethers (specification of U.S. Patent No. 2,448,828), α-hydrocarbon-substituted aromatic acyloin compounds (specification of U.S. Patent No. 2,722,512), polynuclear quinone compounds (specifications of U.S. Patent Nos. 3,046,127 and 2,951,758), a combination of a triarylimidazole dimer and p-aminophenyl ketone (specification of U.S. Patent No. 3,549,367), acridine and phenazine compounds (Japanese Unexamined Patent Application Publication No. 60-105,667 and specification of U.S. Patent No. 4,239,850), oxadiazole compounds (specification of U.S. Patent No. 4,212,970), o-acyl oxime compounds (specification of Japanese Unexamined Patent Application Publication No. 2016-27384

[0065] ), and acylphosphine oxide compounds (Japanese Examined Patent Application Publication No. 63-40,799, Japanese Examined Patent Application Publication No. 5-29,234, Japanese Unexamined Patent Application Publication No. 10-95,788, and Japanese Unexamined Patent Application Publication No. 10-29,997), etc. As such photoinitiators, commercially available products can also be used, including Irgacure-184, Irgacure-907, Irgacure-369, Irgacure-651, Irgacure-819, Irgacure-OXE-01, and Irgacure-OXE-02 manufactured by BASF, etc.

[0237] When the composition for forming a photoabsorptive anisotropic layer contains a photoinitiator, the content of the photoinitiator is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 15 parts by mass, based on 100 parts by mass in total of the dichroic substance and the polymer liquid crystal compound in the composition for forming a photoabsorptive anisotropic layer. When the content of the photoinitiator is 0.01 part by mass or more, the durability of the photoabsorptive anisotropic layer becomes good, and when it is 30 parts by mass or less, the degree of orientation of the photoabsorptive anisotropic layer becomes better. The photoinitiator may be used alone or in combination of two or more. When two or more photoinitiators are included, the total amount thereof is preferably within the above range.

[0238] (Solvent) The composition for forming a photoabsorptive anisotropic layer preferably has a solvent from the viewpoint of workability, etc. Examples of the solvent include organic solvents such as ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, etc.), ethers (e.g., dioxane, tetrahydrofuran, 2-methyltetrahydrofuran, cyclopentyl methyl ether, tetrahydropyran, dioxolane, etc.), aliphatic hydrocarbons (e.g., hexane, etc.), alicyclic hydrocarbons (e.g., cyclohexane, etc.), aromatic hydrocarbons (e.g., benzene, toluene, xylene, trimethylbenzene, etc.), halogenated carbons (e.g., dichloromethane, trichloromethane, dichloroethane, dichlorobenzene, chlorotoluene, etc.), esters (e.g., methyl acetate, ethyl acetate, butyl acetate, ethyl lactate, etc.), alcohols (e.g., ethanol, isopropanol, butanol, cyclohexanol, isopentyl alcohol, neopentyl alcohol, diacetone alcohol, benzyl alcohol, etc.), cellosolves (e.g., methyl cellosolve, ethyl cellosolve, 1,2-dimethoxyethane, etc.), cellosolve acetates, sulfoxides (e.g., dimethyl sulfoxide, etc.), amides (e.g., dimethylformamide, dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, etc.), and heterocyclic compounds (e.g., pyridine, N-methylimidazole, etc.), as well as water. These solvents may be used alone or in combination of two or more. Among these solvents, from the viewpoint of taking advantage of the effect of excellent solubility, ketones (especially cyclopentanone, cyclohexanone), ethers (especially tetrahydrofuran, cyclopentyl methyl ether, tetrahydropyran, dioxolane), and amides (especially dimethylformamide, dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone) are preferred.

[0239] When the composition for forming the light absorption anisotropic layer contains a solvent, the content of the solvent is preferably 80 to 99% by mass, more preferably 83 to 97% by mass, and particularly preferably 85 to 95% by mass with respect to the total mass of the composition for forming the light absorption anisotropic layer. The solvent may be used alone or in combination of two or more. When two or more solvents are included, the total amount thereof is preferably within the above range.

[0240] The light absorption anisotropic film of the present invention may have only the light absorption anisotropic layer, or may be a laminate having other layers as needed. For example, as shown in FIG. 2 described above, the light absorption anisotropic film of the invention may have, in addition to the light absorption anisotropic layer 2, a barrier layer 1, an alignment liquid crystal layer 3, an alignment layer 4, and a TAC film 5.

[0241] <Support> The light absorption anisotropic film of the present invention may have a support for supporting the absorption anisotropic film. In the light absorption anisotropic film 101 shown in FIG. 2, the TAC film 5 is a support. The support is preferably arranged on the surface opposite to the air layer. Further, when the absorption anisotropic film has a protective layer for protecting the light absorption anisotropic layer, the support is preferably arranged on the surface opposite to the surface provided with the protective layer. As the support, known transparent resin films, transparent resin plates, transparent resin sheets, etc. can be used, and there is no particular limitation. Examples of the transparent resin film include cellulose acylate films (e.g., cellulose triacetate film (refractive index 1.48), cellulose diacetate film, cellulose acetate butyrate film, cellulose acetate propionate film), polyethylene terephthalate film, polyethersulfone film, polyacrylic resin film, polyurethane resin film, polyester film, polycarbonate film, polysulfone film, polyether film, polymethylpentene film, polyether ketone film, and (meth)acrylonitrile film, etc.

[0242] Among them, a cellulose acylate film having high transparency, little optical birefringence, easy to manufacture, and generally used as a protective film for a polarizing plate is preferable, and a cellulose triacetate film is particularly preferable. The thickness of the support is usually 20 to 100 μm. In the present invention, it is particularly preferable that the support is a cellulose ester film and its film thickness is 20 to 70 μm.

[0243] <Alignment film> The light absorption anisotropic film of the present invention may have an alignment film between the support and the light absorption anisotropic layer. The alignment film may be any layer as long as it can make the liquid crystal compound serving as the host of the organic dichroic substance on the alignment film have an alignment state in which the angles θA and θB of the alignment direction of the above-mentioned organic dichroic substance are predetermined angles. As the alignment film, for example, a film formed from a polyfunctional acrylate compound or polyvinyl alcohol may be used. Particularly, polyvinyl alcohol is preferable. When tilting the alignment axis, for example, it can be realized by irradiating UV light obliquely from an oblique direction to a photo-alignment film such as an azo compound and a cinnamoyl compound. As a result, it becomes possible to tilt the center of the transmission axis with respect to the normal direction of the film.

[0244] As a preferable alignment film, in the light absorption anisotropic layer, an alignment liquid crystal layer (alignment liquid crystal layer 3 in FIG. 2) for aligning the host liquid crystal compound in the thickness direction so as to satisfy the above angles θA and θB is exemplified. In addition to the alignment liquid crystal layer, the alignment film may have an alignment layer (alignment layer 4 in FIG. 2) for aligning the liquid crystal compound constituting the alignment liquid crystal layer in the in-plane direction, if necessary.

[0245] [Alignment liquid crystal layer] The alignment liquid crystal layer is a hybrid-aligned liquid crystal layer in which the alignment direction in the thickness direction of the liquid crystal compound continuously changes from the support side toward the air side (light-absorbing anisotropic layer side) as shown as the alignment liquid crystal layer 3 in FIG. 2. In other words, the alignment liquid crystal layer is a layer formed by fixing a hybrid-aligned liquid crystal compound whose alignment direction in the thickness direction continuously changes from one surface side toward the other surface side. Preferably, the alignment liquid crystal layer is a layer formed by fixing a polymerizable liquid crystal compound having a hybrid alignment. As a function of the alignment liquid crystal layer, by using the tilt angle of the liquid crystal compound at the air-side interface of the alignment liquid crystal layer, the tilt angle and the tilt direction of the liquid crystal compound at the interface between the light-absorbing anisotropic layer provided thereon and the alignment liquid crystal layer for the alignment film of another liquid crystal layer can be controlled.

[0246] When providing an alignment liquid crystal layer on the light-absorbing anisotropic film of the present invention, it is preferable that the liquid crystal compound in the alignment liquid crystal layer, the light-absorbing anisotropic layer provided thereon, and the liquid crystal compound in other liquid crystal layers are of the same type or similar types. In particular, it is preferable that the liquid crystal compound in the light-absorbing anisotropic layer is a polymer of a polymerizable liquid crystal compound, and the polymerizable liquid crystal compound used in the light-absorbing anisotropic layer and the polymerizable liquid crystal compound used in the alignment liquid crystal layer are the same polymerizable liquid crystal compound. Thereby, the tilt angle and tilt direction control of the light-absorbing anisotropic layer and other liquid crystal layers can be performed more precisely.

[0247] There is no limitation on the thickness of the alignment liquid crystal layer, but in terms of obtaining a good alignment state, etc., about 0.1 to 2.0 μm is preferable.

[0248] Preferably, in addition to the alignment liquid crystal layer, the alignment film has an alignment layer on the support side of the alignment liquid crystal layer for aligning the liquid crystal compound contained in the alignment liquid crystal layer in the in-plane direction. That is, as shown in Fig. 2, the light absorption anisotropic film of the present invention preferably has an alignment layer on a support, an alignment liquid crystal layer on the surface of the alignment layer, and a light absorption anisotropic layer on the surface of the alignment layer liquid crystal layer. In addition, the light absorption anisotropic film of the present invention may have some layer between the support and the alignment layer, if necessary. There is no limitation on the alignment layer, and various known alignment layers can be used as long as they can align the liquid crystal compounds contained in the alignment liquid crystal layer in the in-plane direction, preferably uniaxially. As an example, a layer obtained by rubbing a resin film made of a resin such as polyvinyl alcohol and polyimide, and a layer made of a photo-aligning material such as polyvinyl cinnamate and azobenzene-based compounds, which is subjected to UV exposure with an inclination with respect to the incident angle, are exemplified. Among them, the rubbed polyvinyl alcohol and the rubbed polyimide film are preferably used as the alignment layer. In addition, if the alignment layer can align the liquid crystal compound of the light absorption anisotropic layer not only in the in-plane direction but also in the thickness direction, the alignment liquid crystal layer may not be provided, and the light absorption anisotropic layer may be formed on the surface of the alignment layer.

[0249] <Protective layer> The light absorption anisotropic film of the present invention may have a protective layer for protecting the light absorption anisotropic layer. As the protective layer, various known layers (films) can be used as long as they can protect the light absorption anisotropic layer, and a barrier layer is preferably exemplified. The light absorption anisotropic film shown in Fig. 2 has a barrier layer 1 on the surface of the light absorption anisotropic layer 2 (the side opposite to the support). The barrier layer is also called a gas barrier layer (oxygen barrier layer), and has a function of protecting the polarizing element of the present invention from gases such as oxygen in the atmosphere, moisture, or compounds contained in adjacent layers. Regarding the barrier layer, for example, reference can be made to the descriptions in paragraphs

[0014] to

[0054] of JP-A-2014-159124, paragraphs

[0042] to

[0075] of JP-A-2017-121721, paragraphs

[0045] to

[0054] of JP-A-2017-115076, paragraphs

[0010] to

[0061] of JP-A-2012-213938, and paragraphs

[0021] to

[0031] of JP-A-2005-169994.

[0250] <Refractive index adjustment layer> In the light absorption anisotropic film of the present invention, since the above-described light absorption anisotropic layer has a dichroic substance, internal reflection caused by the high refractive index of the light absorption anisotropic layer may be a problem. In that case, it is preferable that a refractive index adjustment layer is present. The refractive index adjustment layer is a layer arranged to be in contact with the light absorption anisotropic layer, and has an in-plane average refractive index at a wavelength of 550 nm of 1.55 or more and 1.70 or less. It is preferably a refractive index adjustment layer for performing so-called index matching.

[0251] <Other layers> In addition to the above-described layers, the light absorption anisotropic film of the present invention may have layers (films, membranes) that exhibit various functions, such as a retardation layer, an antireflection layer, and various filters, as necessary.

[0252] Note that the light absorption anisotropic film of the present invention is not limited to the configuration shown in FIG. 2, for example, and various layer configurations can be used as long as it has a light absorption anisotropic layer. For example, the light absorption anisotropic film of the present invention may have only a light absorption anisotropic layer, may be composed of a light absorption anisotropic layer and an alignment film, may be composed of a light absorption anisotropic layer and an alignment liquid crystal layer, or may be composed of a light absorption anisotropic layer and a barrier layer.

[0253] <Method for forming light absorption anisotropic layer> The method for forming the light absorption anisotropic layer is not particularly limited, and includes a step of applying the composition for forming the light absorption anisotropic layer to form a coating film (hereinafter, also referred to as the "coating film forming step"), and a step of aligning the liquid crystalline component and the dichroic substance contained in the coating film (hereinafter, also referred to as the "alignment step") in this order. Note that the liquid crystalline component includes not only the liquid crystal compound described above, but also the dichroic substance having liquid crystallinity when the dichroic substance described above has liquid crystallinity.

[0254] [Coating Film Forming Step] The coating film forming step is a step of applying the composition for forming the light absorption anisotropic layer to form a coating film. Preferably, the composition for forming the light absorption anisotropic layer is applied to the surface of the alignment liquid crystal layer described above. By using the composition for forming the light absorption anisotropic layer containing the solvent described above, or by using the composition for forming the light absorption anisotropic layer made into a liquid material such as a melt by heating or the like, it becomes easy to apply the composition for forming the light absorption anisotropic layer. Specific examples of the method for applying the composition for forming the light absorption anisotropic layer include known methods such as roll coating method, gravure printing method, spin coating method, wire bar coating method, extrusion coating method, direct gravure coating method, reverse gravure coating method, die coating method, spray method, and inkjet method.

[0255] [Alignment Step] The alignment step is a step of aligning the liquid crystalline component contained in the coating film. Thereby, a light absorption anisotropic layer is obtained. The alignment step may have a drying process. By the drying process, components such as a solvent can be removed from the coating film. The drying process may be performed by a method of leaving the coating film at room temperature for a predetermined time (for example, natural drying), or may be performed by a method of heating and / or blowing air. Here, the liquid crystalline component contained in the composition for forming the light absorption anisotropic layer may be oriented by the above-described coating film forming step or drying treatment. For example, in an embodiment where the composition for forming the light absorption anisotropic layer is prepared as a coating solution containing a solvent, a coating film having light absorption anisotropy (i.e., a light absorption anisotropic layer) can be obtained by drying the coating film to remove the solvent from the coating film. When the drying treatment is performed at a temperature equal to or higher than the transition temperature of the liquid crystalline component contained in the coating film to the liquid crystal phase, the heat treatment described below may not be necessary.

[0256] The transition temperature of the liquid crystalline component contained in the coating film to the liquid crystal phase is preferably 10 to 250°C, more preferably 25 to 190°C, from the viewpoint of production suitability and the like. When the above transition temperature is 10°C or higher, a cooling treatment or the like for lowering the temperature to the temperature range in which the liquid crystal phase is exhibited is not required, which is preferable. Further, when the above transition temperature is 250°C or lower, a high temperature is not required even when the isotropic liquid state at a temperature higher than the temperature range in which the liquid crystal phase is once exhibited is formed, and waste of thermal energy, as well as deformation and alteration of the substrate can be reduced, which is preferable.

[0257] The alignment step preferably includes a heat treatment. Thereby, the liquid crystalline component contained in the coating film can be aligned, so that the coating film after the heat treatment can be suitably used as the light absorption anisotropic layer. The heat treatment is preferably 10 to 250°C, more preferably 25 to 190°C, from the viewpoint of production suitability and the like. Further, the heating time is preferably 1 to 300 seconds, more preferably 1 to 60 seconds.

[0258] The alignment step may include a cooling treatment performed after the heat treatment. The cooling treatment is a treatment for cooling the coating film after heating to about room temperature (20 to 25°C). Thereby, the alignment of the liquid crystalline component contained in the coating film can be fixed. The cooling means is not particularly limited and can be implemented by a known method. By the above steps, a light absorption anisotropic layer can be obtained. In the above description, drying treatment, heat treatment, etc. are cited as methods for the alignment step, that is, for aligning the liquid crystal components contained in the coating film. However, the alignment step is not limited thereto, and known alignment treatments can be used.

[0259] [Other steps] In the formation of the light absorption anisotropic layer, after the above-described alignment step, a step of curing the light absorption anisotropic layer (hereinafter also referred to as the "curing step") may be included. The curing step is carried out, for example, by heating and / or light irradiation (exposure) when the light absorption anisotropic layer has a crosslinkable group (polymerizable group). Among these, it is preferable that the curing step is carried out by light irradiation. As the light used for curing, various lights (electromagnetic waves) such as infrared rays, visible light, and ultraviolet rays can be used, but ultraviolet rays are preferable. These lights may be carried out using a light source that emits light of a specific wavelength (wavelength range), or the transmitted light may be irradiated through a filter that transmits only light of a specific wavelength (wavelength range). Also, at the time of curing, ultraviolet rays or the like may be irradiated while heating. When light irradiation is carried out while heating, the heating temperature during light irradiation preferably ranges from 25 to 140°C, although it also depends on the transition temperature of the liquid crystal components contained in the liquid crystal film to the liquid crystal phase. Also, the light irradiation may be carried out in a nitrogen atmosphere. When the curing of the liquid crystal film proceeds by radical polymerization, it is preferable to perform light irradiation in a nitrogen atmosphere because the inhibition of polymerization by oxygen is reduced.

[0260] The thickness of the light absorption anisotropic layer is not particularly limited, but from the viewpoint of miniaturization and weight reduction, it is preferably 100 to 8000 nm, and more preferably 300 to 5000 nm.

[0261] <Patterning of the light absorption anisotropic layer> In the light absorption anisotropic film of the present invention, the light absorption anisotropic layer may be a light absorption anisotropic layer having region A and region B in the plane, and the transmission rate central axes are different in each region. By controlling the light-emitting pixels by patterning for each pixel of the liquid crystal, it becomes possible to switch the viewing center of the narrow viewing field. Further, the light absorption anisotropic layer used in the present invention may be a light absorption anisotropic layer having region C and region D in the plane, and in region C and region D, in a plane including the transmission rate central axis and the normal line of the film surface, the transmission rate inclined 30° from the transmission rate central axis in the normal direction is different. In this case, a light absorption anisotropic layer in which the transmission rate inclined 30° from the transmission rate central axis of region C is 50% or less and the transmission rate inclined 30° from the transmission rate central axis of region D is 80% or more is preferable. By performing such patterning, it becomes possible to enhance or weaken the viewing angle dependence in some regions. As a result, it is also possible to display information with a high density of machine only in the region where the viewing angle dependence is enhanced. In addition, by controlling the viewing angle dependence for each display position as a display device, a design excellent in design can also be achieved. Furthermore, by controlling the light-emitting pixels by patterning for each pixel of the liquid crystal, it becomes possible to switch between a narrow viewing angle and a wide viewing angle. In the following description, a light absorption anisotropic layer having two or more different regions in the plane as described above is also referred to as a "pattern light absorption anisotropic layer" for convenience.

[0262] [Pattern formation method] There is no limitation on the method for forming the pattern light absorption anisotropic layer, and for example, various known methods as described in International Publication No. 2019 / 176918 can be used. As an example, a method of forming a pattern by changing the irradiation angle of ultraviolet light irradiated on the photo-alignment film, a method of controlling the thickness of the pattern light absorption anisotropic layer in the plane, a method of unevenly distributing the dichroic substance compound in the pattern light absorption anisotropic layer, a method of post-processing an optically uniform pattern light absorption anisotropic layer, and the like can be mentioned. As a method for controlling the thickness of the pattern light absorption anisotropic layer in the plane, methods such as using lithography, using imprinting, and forming a pattern light absorption anisotropic layer on a substrate having an uneven structure can be mentioned. As a method for unevenly distributing the dichroic substance compound in the pattern light absorption anisotropic layer, a method of extracting the dichroic substance by solvent immersion (bleaching) can be mentioned. Furthermore, as a method for post-processing an optically uniform pattern light absorption anisotropic layer, a method of cutting a part of a flat light absorption anisotropic layer by laser processing or the like can be mentioned.

[0263] The viewing angle control system of the present invention has the above-described light absorption anisotropic film of the present invention and a polarizer.

[0264] <Polarizer> The polarizer used in the viewing angle control system of the present invention is not particularly limited as long as it is a member having a function of converting light into specific linearly polarized light, and a known polarizer can be used.

[0265] As the polarizer, iodine-based polarizers, dye-based polarizers using dichroic substances, polyene-based polarizers, etc. are used. The iodine-based polarizer and the dye-based polarizer include a coating type polarizer and a stretched type polarizer, and either can be used. As the coating type polarizer, a polarizer in which a dichroic organic dye is oriented using the orientation of a liquid crystal compound is preferable. On the other hand, as the stretched type polarizer, a polarizer produced by adsorbing iodine or a dichroic substance on polyvinyl alcohol and stretching it is preferable. In addition, as a method for obtaining a polarizer by performing stretching and dyeing in the state of a laminated film in which a polyvinyl alcohol layer is formed on a substrate, 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 can be mentioned, and known techniques regarding these polarizers can also be preferably used.

[0266] Among them, a polarizer containing a polyvinyl alcohol-based resin (a polymer containing -CH2-CHOH- as a repeating unit. In particular, at least one selected from the group consisting of polyvinyl alcohol and ethylene-vinyl alcohol copolymer) is preferable in terms of easy availability and excellent polarization.

[0267] In the present invention, the thickness of the polarizer is not particularly limited, but is preferably 3 to 60 μm, more preferably 5 to 20 μm, and even more preferably 5 to 10 μm.

[0268] In the viewing angle control system of the present invention, the light absorption anisotropic film and the polarizer may be laminated via an adhesive such as an adhesive layer and an adhesive layer, or the alignment film and the light absorption anisotropy described above may be directly coated and laminated on the polarizer.

[0269] <Adhesive layer> The adhesive layer in the present invention is preferably a transparent and optically isotropic adhesive similar to those used in ordinary image display devices, and usually a pressure-sensitive adhesive is used.

[0270] In addition to the base material (adhesive) and conductive particles, and thermally expandable particles used as necessary, the adhesive layer in the present invention may be blended with appropriate additives such as crosslinking agents (for example, isocyanate-based crosslinking agents and epoxy-based crosslinking agents), tackifiers (for example, rosin derivative resins, polyterpene resins, petroleum resins, and oil-soluble phenol resins), plasticizers, fillers, anti-aging agents, surfactants, ultraviolet absorbers, light stabilizers, and antioxidants.

[0271] The thickness of the adhesive layer is usually 20 to 500 μm, preferably 20 to 250 μm. If it is less than 20 μm, the necessary adhesive strength and reworkability may not be obtained, and if it exceeds 500 μm, the adhesive may protrude or ooze from the peripheral edge of the image display device.

[0272] <Adhesive layer> The adhesive in the present invention exhibits adhesiveness by drying or reaction after bonding. Polyvinyl alcohol-based adhesives (PVA-based adhesives) exhibit adhesiveness upon drying and can bond materials together. Specific examples of curable adhesives that exhibit adhesiveness through reaction include active energy ray curable adhesives such as (meth)acrylate-based adhesives and cationic polymerization curable adhesives. Examples of curable components in (meth)acrylate-based adhesives include compounds having a (meth)acryloyl group and compounds having a vinyl group. In addition, as cationic polymerization curable adhesives, compounds having an epoxy group or an oxetanyl group can also be used. Compounds having an epoxy group are not particularly limited as long as they have at least two epoxy groups in the molecule, and various generally known curable epoxy compounds can be used. Preferred epoxy compounds include compounds having at least two epoxy groups and at least one aromatic ring in the molecule (aromatic epoxy compounds), and compounds having at least two epoxy groups in the molecule, at least one of which is formed between two adjacent carbon atoms constituting an alicyclic ring (alicyclic epoxy compounds), etc. are given as examples. Among them, from the viewpoint of heat distortion resistance, ultraviolet curable adhesives cured by ultraviolet irradiation are preferably used.

[0273] The adhesive layer and the pressure-sensitive adhesive layer may be layers imparted with ultraviolet absorption ability by a method such as treatment with an ultraviolet absorber such as a salicylic acid ester-based compound, a benzophenol-based compound, a benzotriazole-based compound, a cyanoacrylate-based compound, and a nickel complex salt-based compound.

[0274] The attachment of the pressure-sensitive adhesive layer and the adhesive layer to the light absorption anisotropic film and / or the polarizer can be appropriately performed by a known method. As an example, an adhesive solution of about 10 to 40% by mass is prepared by dissolving or dispersing a base polymer or its composition in a solvent composed of a single substance or a mixture of appropriate solvents such as toluene and ethyl acetate, and the adhesive solution is directly attached to a light absorption anisotropic film and / or a polarizer by an appropriate deployment method such as a casting method or a coating method. In addition, as a method for attaching an adhesive layer and an adhesive layer to a light absorption anisotropic film and / or a polarizer, a coating solution containing a base material for forming the adhesive layer, and thermally expandable particles, additives, solvents, etc. added as necessary is prepared, and this coating solution is directly applied onto a support and pressure-bonded through a release liner to produce an adhesive sheet, which can also be used by pressure-transferring (transferring) it from the support. Furthermore, as a method for attaching an adhesive layer and an adhesive layer to a light absorption anisotropic film and / or a polarizer, a thermally expandable adhesive layer is formed by applying the above coating solution onto an appropriate release liner (such as release paper), and this thermally expandable adhesive layer can also be used by pressure-transferring it from the release liner.

[0275] The adhesive layer and the adhesive layer can also be provided on one or both sides of the light absorption anisotropic film and / or the polarizer as a superimposed layer of different compositions or types, etc. Also, when provided on both sides, the adhesive layers can have different compositions, types, thicknesses, etc. on the front and back of the light absorption anisotropic film and / or the polarizer.

[0276] In addition, the light absorption anisotropic film and / or the polarizer may be surface-modified before attaching an adhesive or an adhesive for the purpose of improving adhesion, etc. Specific treatments include corona treatment, plasma treatment, primer treatment, saponification treatment, etc.

[0277] The image display device of the present invention is provided with the viewing angle control system of the present invention on at least one main surface of the display panel.

[0278] In the image display device of the present invention, it is preferable that the angle φ between the plane including the transmission rate central axis of the light absorption anisotropic layer and the normal line of the light absorption anisotropic film and the absorption axis of the polarizer is 45° to 90°, more preferably 80° to 90°, and even more preferably 88° to 90°. The closer this angle φ is to 90°, the more possible it is to create an illuminance contrast between the direction in which the display image by the image display device is visible and the direction in which it is difficult to see.

[0279] <Display panel> There is no limitation on the display panel used in the image display device of the present invention. For example, a liquid crystal cell, an organic electroluminescence (hereinafter abbreviated as "EL") display panel, and a plasma display panel can be mentioned. Among these, a liquid crystal cell or an organic EL display panel is preferable. That is, the image display device of the present invention is preferably a liquid crystal display device using a liquid crystal cell as the display panel or an organic EL display device using an organic EL display panel as the display panel. As an example of the liquid crystal display device of the image display device of the present invention, it is a liquid crystal display device having the above-described viewing angle control system (light absorption anisotropic film and polarizer) of the present invention and a liquid crystal cell. In the present invention, among the polarizing elements provided on both sides of the liquid crystal cell, it is preferable to use the polarizer of the viewing angle control system of the present invention as the front-side or rear-side polarizing element, and it is also possible to use the polarizer of the viewing angle control system of the present invention as the front-side and rear-side polarizing elements.

[0280] Among display panels, there are those that are thin and can be formed into a curved surface. Since the light absorption anisotropic film of the present invention is thin and easy to bend, it can be suitably applied to an image display device with a curved display surface. Also, among display panels, there are those with a pixel density exceeding 250 ppi that enable high-definition display. The light absorption anisotropic film of the present invention can be suitably applied to such a high-definition display panel without generating moire.

[0281] The liquid crystal cell that constitutes the liquid crystal display device will be described in detail below.

[0282] <Liquid crystal cell> The liquid crystal cell used in the liquid crystal display device is preferably in a VA (Vertical Alignment) mode, an OCB (Optically Compensated Bend) mode, an IPS (In-Plane-Switching) mode, or a TN (Twisted Nematic) mode, but is not limited thereto. In the TN mode liquid crystal cell, the rod-shaped liquid crystal compound is substantially horizontally aligned when no voltage is applied, and is further twisted and aligned at 60 to 120°. The TN mode liquid crystal cell is most widely used as a color TFT (Thin Film Transistor) liquid crystal display device and is described in a number of documents. In the VA mode liquid crystal cell, the rod-shaped liquid crystal compound is substantially vertically aligned when no voltage is applied. The VA mode liquid crystal cell includes (1) a narrow-sense VA mode liquid crystal cell (described in Japanese Patent Laid-Open No. 2-176625) in which the rod-shaped liquid crystal compound is substantially vertically aligned when no voltage is applied and substantially horizontally aligned when a voltage is applied, in addition to (2) a liquid crystal cell (in the MVA mode) in which the VA mode is made multi-domain for viewing angle expansion (described in SID97, Digest of tech.Papers (preliminary collection) 28 (1997) 845), (3) a liquid crystal cell in the mode (n-ASM mode) in which the rod-shaped liquid crystal compound is substantially vertically aligned when no voltage is applied and twisted multi-domain aligned when a voltage is applied (described in the proceedings of the Japanese Liquid Crystal Conference 58-59 (1998)), and (4) a liquid crystal cell in the SURVIVAL mode (presented at LCD International 98). Also, the liquid crystal cell may be of any of PVA (Patterned Vertical Alignment) type, optical alignment type, and PSA (Polymer-Sustained Alignment). Details of these modes are described in detail in Japanese Patent Laid-Open No. 2006-215326 and Japanese Patent Publication No. 2008-538819. In an IPS mode liquid crystal cell, rod-shaped liquid crystal compounds are aligned substantially parallel to the substrate, and when an electric field parallel to the substrate surface is applied, the liquid crystal compounds respond planarially. In the IPS mode, black display is achieved in the absence of an electric field, and the absorption axes of the pair of upper and lower polarizing plates are orthogonal. Regarding the IPS mode, methods for reducing leakage light during black display in an oblique direction and improving the viewing angle by using an optical compensation sheet are disclosed in, for example, Japanese Unexamined Patent Application Publication Nos. 10-54982, 11-202323, 9-292522, 11-133408, 11-305217, and 10-307291.

[0283] When it is necessary to attach the display cell and the viewing angle control system of the present invention in the image display device of the present invention, a known method such as using an adhesive exemplified by the attachment of the light absorption anisotropic film and the polarizer in the viewing angle control system may be used for attachment.

Example

[0284] The present invention will be described more specifically with reference to the following examples. The materials, reagents, amounts of substances and their ratios, operations, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention is not limited to the following specific examples.

[0285] [Example 1] A light absorption anisotropic film having a light absorption anisotropic layer in which an organic dichroic substance is obliquely aligned was prepared as follows.

[0286] [Production of Transparent Support 1] The surface of a cellulose acetate film 1 (a TAC substrate with a thickness of 40 μm; TG40, manufactured by Fuji Film Co., Ltd.) was saponified with an alkaline solution, and the following coating solution 1 for forming an alignment layer was applied thereon with a wire bar. The support on which the coating film was formed was dried with warm air at 60°C for 60 seconds and then with warm air at 100°C for 120 seconds to form an alignment layer 1, and a TAC film with an alignment layer was obtained. The film thickness was 0.5 μm. The produced TAC film with an alignment layer was used after rubbing the alignment film surface.

[0287] ―――――――――――――――――――――――――――――――― (Coating liquid 1 for forming alignment layer) ―――――――――――――――――――――――――――――――― · 3.80 parts by mass of the following modified polyvinyl alcohol · 0.20 parts by mass of initiator Irg2959 · 70 parts by mass of water · 30 parts by mass of methanol ――――――――――――――――――――――――――――――――

[0288] Modified polyvinyl alcohol

[0289]

Chemical formula

[0290] <Fabrication of alignment liquid crystal layer> On the alignment film of the produced TAC film with an alignment layer, a composition T1 for forming an alignment liquid crystal layer with the following composition was applied using a wire bar to prepare a coating layer T1. Next, the coating layer T1 of the alignment liquid crystal layer was heated at 120 °C for 30 seconds and then cooled to room temperature (23 °C). It was further heated at 80 °C for 60 seconds and then cooled to room temperature again. After that, using an LED lamp (central wavelength 365 nm), under irradiation conditions of illuminance 200 mW / cm 2 it was irradiated for 1 second to fabricate an alignment liquid crystal layer T1 on the alignment layer 1. The film thickness of the alignment liquid crystal layer T1 was 0.25 μm, and the surface energy was 35.0 mN / m.

[0291] ――――――――――――――――――――――――――――――――― Composition of the composition T1 for forming an alignment liquid crystal layer ――――――――――――――――――――――――――――――――― ·55.20 parts by mass of the following polymer liquid crystal compound P-1 ·40.49 parts by mass of the following low-molecular liquid crystal compound M-1 ·Polymerization initiator IRGACURE OXE-02 (manufactured by BASF) 4.049 parts by mass ·The following surfactant F-1 (leveling agent) 0.2620 parts by mass ·Cyclopentanone 660.6 parts by mass ·Tetrahydrofuran 660.6 parts by mass ―――――――――――――――――――――――――――――――――

[0292] Polymer liquid crystal compound P-1

[0293]

Chemical formula

[0294] Low-molecular liquid crystal compound M-1

[0295]

Chemical formula

[0296] Surfactant F-1

[0297]

Chemical formula

[0298] <Formation of the light absorption anisotropic layer P1> On the obtained alignment liquid crystal layer T1, the following light absorption anisotropic layer forming composition P1 was applied with a wire bar to form a coating layer P1. Next, the coating layer P1 was heated at 120 °C for 30 seconds and cooled until it reached room temperature (23 °C). Next, it was heated at 80 °C for 60 seconds and cooled again until it reached room temperature. Thereafter, using an LED lamp (central wavelength 365 nm), irradiation was performed for 1 second under irradiation conditions of an illuminance of 200 mW / cm 2 to fabricate a light absorption anisotropic layer P1 on the alignment layer 1. The film thickness of the light absorption anisotropic layer P1 was 1.4 μm, and the surface energy was 26.5 mN / m.

[0299] ――――――――――――――――――――――――――――――――― Composition of the composition P1 for forming the light absorption anisotropic layer ――――――――――――――――――――――――――――――――― · 7.356 parts by mass of the following dichroic substance D-1 · 3.308 parts by mass of the following dichroic substance D-2 · 11.02 parts by mass of the following dichroic substance D-3 · 43.29 parts by mass of the polymer liquid crystal compound P-1 · 31.75 parts by mass of the low-molecular liquid crystal compound M-1 · Polymerization initiator IRGACURE OXE-02 (manufactured by BASF) 3.175 parts by mass · The following surfactant F-2 (leveling agent) 0.1027 parts by mass · Cyclopentanone 514.4 parts by mass · Tetrahydrofuran 514.4 parts by mass ―――――――――――――――――――――――――――――――――

[0300] Dichroic substance D-1

[0301]

Chemical formula

[0302] Dichroic substance D-2

[0303]

Chemical formula

[0304] Dichroic substance D-3

[0305]

Chem.

[0306] Surfactant F-2

[0307]

Chem.

[0308] <Formation of Barrier Layer B1> On the prepared photoabsorptive anisotropic layer P1, the following composition B1 for forming a barrier layer was applied with a wire bar and dried at 80 °C for 5 minutes to form a barrier coating layer B1. Subsequently, the barrier coating layer B1 was irradiated for 2 seconds under the irradiation conditions of an oxygen concentration of 100 ppm, a temperature of 60 °C, and an illuminance of 150 mW / cm 2 using an LED lamp (center wavelength 365 nm) to form a barrier layer B1 on the photoabsorptive anisotropic layer P1. The thickness of the barrier layer B1 was 1.0 μm. This was designated as the photoabsorptive anisotropic film P1.

[0309] ――――――――――――――――――――――――――――――――― (Composition B1 for Forming Barrier Layer) ――――――――――――――――――――――――――――――――― · The following modified polyvinyl alcohol: 3.80 parts by mass · Initiator Irg2959: 0.20 parts by mass · Water: 70 parts by mass · Methanol: 30 parts by mass ―――――――――――――――――――――――――――――――――

[0310] Modified polyvinyl alcohol

Chem.

[0311] <Measurement of the orientation angle of the light absorption anisotropic layer> Regarding the fabricated light absorption anisotropic film P1, the Mueller matrix at a wavelength of 550 nm was measured using AxoScan OPMF-1 (manufactured by OptoSciences). Specifically, first, using AxoScan OPMF-1, the azimuth angle at which the transmittance central axis was inclined was first searched for. Next, within the plane containing the normal direction of the light absorption anisotropic layer along that azimuth angle, that is, the plane containing the transmittance central axis and orthogonal to the main plane of the light absorption anisotropic layer, while changing the polar angle, which is the angle with respect to the normal direction of the light absorption anisotropic layer, by 1° from -70° to 70°, the Mueller matrix at a wavelength of 550 nm was actually measured, and the transmittance of the light absorption anisotropic layer was derived. From this result, the direction with the highest transmittance was set as the transmittance central axis. Note that the transmittance central axis means the direction in which the absorption axis (long axis direction of the molecule) of the dichroic substance contained in the light absorption anisotropic layer is inclined. Furthermore, as shown in FIG. 6, a section 43 with a thickness of 2 μm was taken by a microtome in parallel with the plane including the transmittance central axis and the film normal 42. Furthermore, as shown in FIG. 7, on the rotating stage of the polarizing microscope, the azimuth angle (the angle for rotating the section 43) at which the cross section of the light absorption anisotropic layer was most extinguished with respect to the incident linearly polarized light was obtained. In this case, the analyzer of the polarizing microscope was not used. The angle θA formed by the orientation direction of the light absorption axis of the organic dichroic substance in the vicinity of the interface on the support side of the light absorption anisotropic layer and the normal of the light absorption anisotropic layer obtained by this observation was 30°. Furthermore, the angle θB formed by the orientation direction of the light absorption axis of the organic dichroic substance in the vicinity of the interface on the air side of the light absorption anisotropic layer and the normal of the light absorption anisotropic layer was 17°. The measurement of such an angle θA and angle θB was performed by cutting out three sections (n = 3), and the average value was taken as the angle θA and angle θB in this light absorption anisotropic layer. In this regard, the same applies to other examples and comparative examples. Note that the measurement of the angles θA and θB was performed at a position 0.2 μm inside from both interfaces, as described above with reference to FIG. 5. Also, in the following examples, the measurement of the angles θA and θB of the light absorption anisotropic layer was performed in the same manner as in this example.

[0312] <Fabrication of laminate A1> In the same manner as the polarizing plate 02 with a single-sided protective film described in International Publication No. 2015 / 166991, a polarizing plate 1 with a thickness of 8 μm and one side of the polarizer exposed was fabricated. The exposed surface of the polarizer of the above polarizing plate 1 and the surface of the fabricated light absorption anisotropic film 1 were corona-treated and bonded using the following PVA adhesive 1 to fabricate laminate A1. At this time, as shown in FIG. 4, the angle formed by the transmission rate central axis 22 (polar angle θ) of the light absorption anisotropic layer and the normal line 23 of the light absorption anisotropic layer 2 (light absorption anisotropic film) and the absorption axis 24 of the polarizer 21 was 90°.

[0313] (Preparation of PVA adhesive 1) To 100 parts of a polyvinyl alcohol-based resin containing an acetoacetyl group (average degree of polymerization: 1200, saponification degree: 98.5 mol%, acetoacetylation degree: 5 mol%), 20 parts of methylol melamine was dissolved in pure water under a temperature condition of 30 °C to prepare an aqueous solution adjusted to a solid content concentration of 3.7%.

[0314] <Fabrication of image display device B1> An iPad Air (registered trademark, the same applies hereinafter) Wi-Fi model 16GB (manufactured by APPLE), which is an IPS-mode liquid crystal display device, was disassembled, and the liquid crystal cell was taken out. The fabricated laminate A1 was bonded to the surface from which the viewing-side polarizing plate was peeled off from the liquid crystal cell using the following adhesive sheet 1 with the polarizing plate 1 side facing the liquid crystal cell side. At this time, it was bonded so that the direction of the absorption axis of the polarizing plate 1 was in the longitudinal direction of the liquid crystal screen. After bonding to the liquid crystal cell, it was reassembled to fabricate image display device B1.

[0315] (Preparation of adhesive sheet 1) An acrylate-based polymer was prepared according to the following procedure. In a reaction vessel equipped with a cooling pipe, a nitrogen introduction 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 having an average molecular weight of 2 million and a molecular weight distribution (Mw / Mn) of 3.0.

[0316] Next, to the obtained acrylate polymer A1 (100 parts by mass), Coronate L (a 75 mass% ethyl acetate solution of a trimethylolpropane adduct of tolylene diisocyanate, the number of isocyanate groups in one molecule: 3, manufactured by Nippon Polyurethane Industry Co., Ltd.) (1.0 part by mass) and silane coupling agent KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd.) (0.2 part by mass) were mixed, and finally ethyl acetate was added so that the total solid content concentration became 10 mass% to prepare a composition for forming an adhesive. This composition was applied to a separate film surface-treated with a silicone-based release agent using a die coater and dried in an environment at 90 °C for 1 minute to obtain an acrylate adhesive sheet. The film thickness was 25 μm and the storage elastic modulus was 0.1 MPa.

[0317] [Example 2] An optical absorption anisotropic film P2, a laminate A2, and an image display device B2 were produced in the same manner as in Example 1, except that the thickness of the liquid crystal layer for alignment was 0.33 μm. The surface energy of the liquid crystal layer for alignment was 36.1 mN / m, the angle θA of the optical absorption anisotropic layer of the optical absorption anisotropic film was 24°, and the angle θB was 18°.

[0318] [Example 3] An optical absorption anisotropic film P3, a laminate A3, and an image display device B3 were produced in the same manner as in Example 1, except that the thickness of the liquid crystal layer for alignment was 0.46 μm. The surface energy of the liquid crystal layer for alignment was 37.5 mN / m, the angle θA of the optical absorption anisotropic layer of the optical absorption anisotropic film was 19°, and the angle θB was 18°.

[0319] [Example 4] When forming the light absorption anisotropic layer, the composition of the composition for forming the light absorption anisotropic layer was set to the composition of the following composition P2 for forming the light absorption anisotropic layer, and the light absorption anisotropic film P4, the laminate A4, and the image display device B4 were produced in the same manner as in Example 1 except that the film thickness of the light absorption anisotropic layer was 4.0 μm. Here, it was confirmed in advance that the low-molecular liquid crystal compounds M-2 and M-3 exhibit a smectic phase by observing the liquid crystal phase while changing the temperature using a hot stage for a microscope (manufactured by METTLER TOLEDO) and a polarizing microscope. The surface energy of the alignment liquid crystal layer was 35.0 mN / m, the angle θA of the light absorption anisotropic layer of the light absorption anisotropic film was 35°, and the angle θB was 27°.

[0320] ――――――――――――――――――――――――――――――――― Composition of the composition P2 for forming the light absorption anisotropic layer ――――――――――――――――――――――――――――――――― · Dichroic substance D-1 2.872 parts by mass · Dichroic substance D-2 1.026 parts by mass · Dichroic substance D-3 4.513 parts by mass · The following low-molecular liquid crystal compound M-2 67.90 parts by mass · The following low-molecular liquid crystal compound M-3 22.56 parts by mass · Polymerization initiator IRGACURE OXE-02 (manufactured by BASF) 0.8205 parts by mass · Surfactant F-2 (levelling agent) 0.1000 parts by mass · Cyclopentanone 1846.2 parts by mass · Benzyl alcohol 102.6 parts by mass ―――――――――――――――――――――――――――――――――

[0321] Low-molecular liquid crystal compound M-2

[0322]

Chemical formula

[0323] Low-molecular liquid crystal compound M-3

[0324]

Chem.

[0325] [Example 5] When forming the light absorption anisotropic layer, the composition of the composition for forming the light absorption anisotropic layer was made the same as the composition of the following composition P3 for forming the light absorption anisotropic layer, and the film thickness of the light absorption anisotropic layer was 4.0 μm. Otherwise, in the same manner as in Example 1, a light absorption anisotropic film P5, a laminate A5, and an image display device B5 were produced. Here, it was previously confirmed by observing the liquid crystal phase while changing the temperature using a hot stage for a microscope (manufactured by METTLER TOLEDO) and a polarizing microscope that the low-molecular liquid crystal compounds M-4 and M-5 exhibit a smectic phase. The surface energy of the alignment liquid crystal layer was 35.5 mN / m, the angle θA of the light absorption anisotropic layer of the light absorption anisotropic film was 34°, and the angle θB was 26°.

[0326] ――――――――――――――――――――――――――――――――― Composition of the composition P3 for forming the light absorption anisotropic layer ――――――――――――――――――――――――――――――――― · Dichroic substance D-1 2.872 parts by mass · Dichroic substance D-2 1.026 parts by mass · Dichroic substance D-3 4.513 parts by mass · The following low-molecular liquid crystal compound M-4 67.90 parts by mass · The following low-molecular liquid crystal compound M-5 22.56 parts by mass · Polymerization initiator IRGACURE OXE-02 (manufactured by BASF) 0.8205 parts by mass · Surfactant F-2 (leveling agent) 0.1000 parts by mass · Cyclopentanone 1846.2 parts by mass · Benzyl alcohol 102.6 parts by mass ―――――――――――――――――――――――――――――――――

[0327] Low-molecular liquid crystal compound M-4

[0328]

Chem.

[0329] Low-molecular liquid crystal compound M-5

[0330]

Chem.

[0331] [Example 6] When forming the light absorption anisotropic layer, the light absorption anisotropic film P6, the laminate A6, and the image display device B6 were produced in the same manner as in Example 1, except that the composition of the composition for forming the light absorption anisotropic layer was set to the composition of the following composition for forming the light absorption anisotropic layer P4 and the film thickness of the light absorption anisotropic layer was set to 1.7 μm. The surface energy of the alignment liquid crystal layer was 34.9 mN / m, the angle θA of the light absorption anisotropic layer of the light absorption anisotropic film was 30°, and the angle θB was 17°.

[0332] ――――――――――――――――――――――――――――――――― Composition of the composition for forming the light absorption anisotropic layer P4 ――――――――――――――――――――――――――――――――― · Dichroic substance D-1 5.056 parts by mass · Dichroic substance D-2 2.274 parts by mass · Dichroic substance D-3 7.578 parts by mass · High-molecular liquid crystal compound P-1 43.29 parts by mass · Low-molecular liquid crystal compound M-1 31.75 parts by mass · Polymerization initiator IRGACURE OXE-02 (manufactured by BASF) 3.175 parts by mass · Surfactant F-2 (leveling agent) 0.1027 parts by mass · 490.5 parts by mass of cyclopentanone · 490.5 parts by mass of tetrahydrofuran ―――――――――――――――――――――――――――――――――

[0333] [Example 7] When forming the light-absorbing anisotropic layer, except that the composition of the composition for forming the light-absorbing anisotropic layer was set to the composition of the following composition for forming the light-absorbing anisotropic layer P5 and the film thickness of the light-absorbing anisotropic layer was set to 4.6 μm, in the same manner as in Example 1, a light-absorbing anisotropic film P7, a laminate A7, and an image display device B7 were produced. The surface energy of the alignment liquid crystal layer was 35.1 mN / m, the angle θA of the light-absorbing anisotropic layer of the light-absorbing anisotropic film was 31°, and the angle θB was 17°.

[0334] ――――――――――――――――――――――――――――――――― Composition of the composition for forming the light-absorbing anisotropic layer P5 ――――――――――――――――――――――――――――――――― · 1.720 parts by mass of dichroic substance D-1 · 0.7736 parts by mass of dichroic substance D-2 · 2.578 parts by mass of dichroic substance D-3 · 43.29 parts by mass of polymer liquid crystal compound P-1 · 31.75 parts by mass of low-molecular liquid crystal compound M-1 · Polymerization initiator IRGACURE OXE-02 (manufactured by BASF) 3.175 parts by mass · Surfactant F-2 (leveling agent) 0.1027 parts by mass · 436.5 parts by mass of cyclopentanone · 436.5 parts by mass of tetrahydrofuran ―――――――――――――――――――――――――――――――――

[0335] [Example 8] When forming the light absorption anisotropic layer, except that the composition of the composition for forming the light absorption anisotropic layer was set to the composition of the composition P6 for forming the light absorption anisotropic layer below and the film thickness of the light absorption anisotropic layer was set to 4.6 μm, a light absorption anisotropic film P8, a laminate A8, and an image display device B8 were produced in the same manner as in Example 1. The surface energy of the alignment liquid crystal layer was 35.0 mN / m, the angle θA of the light absorption anisotropic layer of the light absorption anisotropic film was 31°, and the angle θB was 18°.

[0336] ――――――――――――――――――――――――――――――――― Composition of the composition P6 for forming the light absorption anisotropic layer ――――――――――――――――――――――――――――――――― · Dichroic substance D-1 1.094 parts by mass · Dichroic substance D-2 0.4917 parts by mass · Dichroic substance D-3 1.639 parts by mass · Polymer liquid crystal compound P-1 43.29 parts by mass · Low molecular liquid crystal compound M-1 31.75 parts by mass · Polymerization initiator IRGACURE OXE-02 (manufactured by BASF) 3.175 parts by mass · Surfactant F-2 (leveling agent) 0.1027 parts by mass · Cyclopentanone 432.2 parts by mass · Tetrahydrofuran 432.2 parts by mass ―――――――――――――――――――――――――――――――――

[0337] [Comparative Example 1] An alignment liquid crystal layer was not provided, and the composition for forming the light absorption anisotropic layer was directly applied onto the rubbed PVA alignment layer to provide a film thickness of the light absorption anisotropic layer. A light absorption anisotropic film P10, a laminate A10, and an image display device B10 were produced in the same manner as in Example 1, except that the film thickness of the light absorption anisotropic layer was set to 3.0 μm. The angle θA of the light absorption anisotropic layer of the light absorption anisotropic film was 80°, and the angle θB was 50°.

[0338] [Comparative Example 2] An optical absorption anisotropy film P11, a laminate A11, and an image display device B11 were produced in the same manner as in Example 1, except that the thickness of the alignment liquid crystal layer was 0.10 μm and the thickness of the optical absorption anisotropy layer was 1.7 μm. The surface energy of the alignment liquid crystal layer was 34.0 mN / m, the angle θA of the optical absorption anisotropy layer of the optical absorption anisotropy film was 45°, and the angle θB was 28°.

[0339] [Evaluation of Performance] (1) Evaluation of maximum transmittance Using the produced optical absorption anisotropy film, in AxoScan OPMF-1 (manufactured by Opto Science Co., Ltd.), the Mueller matrix of the optical absorption anisotropy film at a wavelength of 550 nm was measured at every 1° from the polar angle of -70° to 70°. From this measurement result, the maximum transmittance Tmax at the angle θ at which the transmittance is maximum was measured. The image display devices produced in each example and comparative example were observed from the angle θ obtained above, and evaluated according to the following criteria. AAA: The image is bright and very easy to view (transmittance 0.8 or more) AA: The image is bright and easy to view (transmittance 0.7 or more and less than 0.8) A: The image is slightly bright and easy to view (transmittance 0.6 or more and less than 0.7) B: The image is slightly dark and difficult to view (transmittance 0.5 or more and less than 0.6) C: The image is dark and difficult to view (transmittance 0.4 or more and less than 0.5) D: The image is dark and very difficult to view (transmittance less than 0.4)

[0340] (2) Evaluation of reflection of the image on the window glass The image display devices B1 to B8 produced by the above procedure were fixed in a state where the display screen was standing vertically with respect to the ground. Further, a glass plate with a thickness of 2 mm was installed at an angle perpendicular to the display screen and the ground, on the side opposite to the direction in which the transmission rate central axis of the light absorption anisotropic layer was directed. Further, the interior of the room was made a darkroom, a sample image was displayed on the display, and the reflection of the image on the glass and the brightness of the image when viewed from the direction of the transmission rate central axis were visually evaluated by sensory evaluation in the darkroom. AAA: No reflection on the glass is visible AA: Almost no reflection on the glass is visible A: Reflection on the glass is hardly visible B: A little reflection on the glass is visible C: Reflection on the glass is visible D: Strong reflection on the glass is visible

[0341] Table 1 shows the results of each example and comparative example.

[0342]

Table 1

[0343] As shown in the above table, as the difference between the angle θA formed by the orientation direction of the light absorption axis of the organic dichroic substance and the normal of the light absorption anisotropic layer at the interface on the support side of the light absorption anisotropic layer, and the angle θB formed by the orientation direction of the light absorption axis of the dichroic substance and the normal of the light absorption anisotropic layer at the interface on the air side of the light absorption anisotropic layer decreases, the visibility (maximum transmittance) of the screen from the observer increases, and at the same time, the reflection on the window glass also decreases. In particular, as shown in Example 3, in the region where the difference between the angle θA and the angle θB is 2° or less, both the visibility from the observer and the smallness of the reflection on the window glass are at a very good level. Also, as shown in Examples 1 to 6, and Examples 7 and 8, the higher the dye content in the light absorption anisotropic layer, the more improved the visibility from the observer and the less reflection on the window glass tend to be. This is presumably because as the alignment with an increased amount of dye in the film is obtained, the contrast becomes easier to obtain. On the other hand, in Comparative Examples 1 and 2 where the angle θA is 45° or more and the difference between the angle θA and the angle θB exceeds 15°, the visibility of the image is poor, and furthermore, there is a lot of reflection of the image on the window glass.

Explanation of Signs

[0344] 100 Liquid crystal display device 101 Light absorption anisotropic film 102 Polarizer on the viewing side 103 Liquid crystal cell 104 Polarizer on the backlight side 105 Backlight 1 Barrier layer 2 Light absorption anisotropic layer 3 Liquid crystal layer for alignment 4 Alignment layer 5 TAC film 11 Liquid crystal compound 13 Dichroic substance D-1 14 Dichroic substance D-2 15 Dichroic substance D-3 21 Polarizer 22 Transmission rate central axis direction (polar angle θ) 23 Normal line of the light absorption anisotropic layer 24 Absorption axis direction of the polarizer 31 Air side interface of the light absorption anisotropic layer 32 Support side interface of the light absorption anisotropic layer 33 Angle (θB) 34 Angle (θA) 35 Normal line of the absorption anisotropic layer 42 Normal line direction of the light absorption anisotropic film 43 Section of the light absorption anisotropic film

Claims

1. A light absorption anisotropic film having a light absorption anisotropic layer and an alignment liquid crystal layer adjacent to the light absorption anisotropic layer, wherein the light absorption anisotropic layer contains a liquid crystal compound and an organic dichroic substance, wherein, when the angle formed by the alignment direction of the light absorption axis of the organic dichroic substance on one surface of the light absorption anisotropic layer and the normal of the light absorption anisotropic layer is θA, and the angle formed by the alignment direction of the light absorption axis of the dichroic substance on the other surface of the light absorption anisotropic layer and the normal of the light absorption anisotropic layer is θB, the difference between the angle θA and the angle θB is 15° or less, and the angle θA is 5° or more and less than 45°, the alignment liquid crystal layer is a layer formed by fixing a hybrid-aligned polymerizable liquid crystal compound in which the alignment direction in the thickness direction continuously changes from one surface side to the other surface side, and further, a light absorption anisotropic film having a thickness of the alignment liquid crystal layer of 0.1 to 2.0 μm.

2. The light absorption anisotropic film according to claim 1, wherein the difference between the angle θA and the angle θB is 5° or less.

3. The light absorption anisotropic film according to claim 1 or 2, wherein the difference between the angle θA and the angle θB is 2° or less.

4. The light absorption anisotropic film according to any one of claims 1 to 3, wherein the ratio of the organic dichroic substance to the total solid mass of the light absorption anisotropic layer is 5% by mass or more.

5. The light absorption anisotropic film according to any one of claims 1 to 3, wherein the ratio of the organic dichroic substance to the total solid mass of the light absorption anisotropic layer is 15% by mass or more.

6. The light absorption anisotropic film according to any one of claims 1 to 5, wherein the organic dichroic substance is composed of a mixture of three or more types of organic dichroic substances having different absorption peak wavelengths.

7. The light absorption anisotropic film according to any one of claims 1 to 6, wherein the liquid crystal compound contains a polymer liquid crystal compound.

8. The light absorption anisotropic film according to any one of claims 1 to 7, wherein the liquid crystal compound is a polymer of a polymerizable liquid crystal compound.

9. The light absorption anisotropic film according to claim 8, wherein the polymerizable liquid crystal compound contains a rod-shaped liquid crystal compound.

10. The light absorption anisotropic film according to claim 8 or 9, wherein the polymerizable liquid crystal compound contains a liquid crystal compound exhibiting a smectic phase.

11. The liquid crystal compound of the light absorption anisotropic layer is a polymer of a polymerizable liquid crystal compound, The light absorption anisotropic film according to any one of claims 1 to 10, wherein the polymerizable liquid crystal compound used in the light absorption anisotropic layer and the polymerizable liquid crystal compound used in the alignment liquid crystal layer are the same polymerizable liquid crystal compound.

12. The light absorption anisotropic film according to any one of claims 1 to 11, having an alignment layer made of polyvinyl alcohol or polyimide adjacent to the opposite side of the alignment liquid crystal layer from the light absorption anisotropic layer.

13. A viewing angle control system having a polarizer and the light absorption anisotropic film according to any one of claims 1 to 12.

14. An image display device in which the viewing angle control system according to claim 13 is disposed on at least one main surface of a display panel.

Images