Laminate, liquid crystal display device, and in-vehicle display

Abstract

The purpose of the present invention is to provide a laminate which, when used as a member for a liquid crystal display device, can control the viewing angle of the obtained liquid crystal display device, and which has excellent light blocking properties and excellent light resistance. This laminate has a first light-absorbing anisotropic layer, a first polarizer, a first liquid crystal cell, a second polarizer, a second liquid crystal cell, and a second light-absorbing anisotropic layer in this order, and is characterized in that: the absorption axis of the first polarizer is orthogonal to the absorption axis of the second polarizer; the first light-absorbing anisotropic layer and the second light-absorbing anisotropic layer contain a dichroic material, and the angle [theta] 1 formed by the transmittance center axis of the first light-absorbing anisotropic layer and the normal direction of the surface of the first light-absorbing anisotropic layer is 0-45 degrees. The angle [theta] 2 formed by the transmittance center axis of the second light-absorbing anisotropic layer and the normal direction of the surface of the second light-absorbing anisotropic layer is 0-45 degrees.

Description

Technical Field

[0001] The present invention relates to a laminate, a liquid crystal display device, and an in-vehicle display. Background Art

[0002] In recent years, display devices such as liquid crystal display devices have been widely used as displays for personal computers, smartphones, etc. Moreover, displays are also frequently used in mobile devices. Devices with such displays are often used in public places, so technologies for preventing others from peeping are required.

[0003] Furthermore, in recent years, liquid crystal display devices have been used as in-vehicle displays inside automobiles. With the enlargement of in-vehicle displays, the images displayed on the displays may sometimes be reflected in the windshield or the like, which may sometimes obstruct the driver's view, so technologies for preventing reflection are required.

[0004] Moreover, in the above-described displays, it is also preferable to be able to switch the viewing angle width as needed.

[0005] For example, Patent Document 1 discloses an optical laminate that sequentially includes at least a first light absorption anisotropic layer, a refractive index anisotropic layer containing a liquid crystalline compound having one or more twisted structures, and a second light absorption anisotropic layer. The first light absorption anisotropic layer and the second light absorption anisotropic layer contain an anisotropic absorption material, and the absorption axis is oriented at an angle of 60 degrees to 90 degrees with respect to the film surface. The following is described: In the above optical laminate, by replacing the liquid crystalline compound having a twisted structure with a TN (Twisted Nematic) liquid crystal cell or a VATN (Vertical ly Aligned Twisted Nematic) liquid crystal cell and electrically controlling the refractive anisotropy of the liquid crystal layer, it is possible to electrically control a narrow viewing field and a wide viewing field in a liquid crystal display device.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: International Publication No. 2021 / 210359 Summary of the Invention

[0009] Technical Problem to be Solved by the Invention

[0010] Regarding a liquid crystal display device, it is desired that when visually recognizing the liquid crystal display device from an inclined direction at a specific azimuth angle, the image of the liquid crystal display device cannot be visually recognized at all times, and when visually recognizing the liquid crystal display device from an inclined direction at an azimuth angle different from the above-mentioned specific azimuth angle (for example, an azimuth angle orthogonal to the above-mentioned specific azimuth angle), the visual recognition of the image of the liquid crystal display device can be switched. In a liquid crystal display device having the above-mentioned characteristics, when mounted on an automobile, it is possible to prevent the image from being projected onto the windshield while being able to switch the visual recognition of the image of the liquid crystal display device from the driver's seat or the passenger seat. Hereinafter, a liquid crystal display device having the above-mentioned characteristics (when visually recognizing the liquid crystal display device from an inclined direction at a specific azimuth angle, the image of the liquid crystal display device cannot be visually recognized at all times, and when visually recognizing the liquid crystal display device from an inclined direction at an azimuth angle different from the above-mentioned specific azimuth angle, the visual recognition of the image of the liquid crystal display device can be switched) and the like is referred to as a liquid crystal display device "capable of viewing angle control".

[0011] In the above-mentioned liquid crystal display device, it is required that in a mode where the image cannot be visually recognized from the inclined direction, the brightness when visually recognizing from the inclined direction is sufficiently darker than the brightness when visually recognizing from the front direction. Hereinafter, this characteristic is also referred to as "light shielding property".

[0012] Moreover, the above-mentioned liquid crystal display device is sometimes used in an environment irradiated with sunlight or the like, so it is required to maintain the above-mentioned light shielding property even after being irradiated with light for a long time. Hereinafter, the characteristic of maintaining the above-mentioned light shielding property even after being irradiated with light for a long time is also referred to as "light resistance".

[0013] As a result of the inventors' research on the optical laminate described in Patent Document 1, it was found that it is impossible to balance the above-mentioned light shielding property and light resistance, and it was also found that there is room for further improvement.

[0014] Therefore, in the present invention, the problem is to provide a laminate that, when applied as a component of a liquid crystal display device, can perform viewing angle control of the obtained liquid crystal display device, and has excellent light shielding property and further excellent light resistance of the obtained liquid crystal display device.

[0015] Moreover, the problem of the present invention is also to provide a liquid crystal display device and an in-vehicle display using the above-mentioned laminate.

[0016] Means for Solving Technical Problems

[0017] As a result of the inventors' in-depth research to solve the above-mentioned problems, the present invention has been completed. That is, it has been found that the above-mentioned problems can be solved by the following structure.

[0018] 〔1〕A laminate having, in order:[[]]

[0019] The first light absorption anisotropic layer;

[0020] The first polarizer;

[0021] The first liquid crystal cell;

[0022] The second polarizer;

[0023] The second liquid crystal cell; and

[0024] The second light absorption anisotropic layer, wherein,

[0025] The absorption axis of the above-mentioned first polarizer is orthogonal to the absorption axis of the above-mentioned second polarizer,

[0026] The above-mentioned first light absorption anisotropic layer and the above-mentioned second light absorption anisotropic layer contain dichroic substances,

[0027] The angle θ1 formed by the transmittance central axis of the above-mentioned first light absorption anisotropic layer and the normal direction of the surface of the above-mentioned first light absorption anisotropic layer is 0 to 45°,

[0028] The angle θ2 formed by the transmittance central axis of the above-mentioned second light absorption anisotropic layer and the normal direction of the surface of the above-mentioned second light absorption anisotropic layer is 0 to 45°.

[0029] 〔2〕The laminate according to 〔1〕, wherein,

[0030] The above-mentioned dichroic substances have an arrangement structure of the dichroic substances with respect to each other in the above-mentioned first light absorption anisotropic layer and the above-mentioned second light absorption anisotropic layer.

[0031] 〔3〕The laminate according to 〔1〕 or 〔2〕, wherein,

[0032] The above-mentioned first liquid crystal cell and the above-mentioned second liquid crystal cell are each independently selected from the group including a twisted nematic liquid crystal cell, an in-plane switching liquid crystal cell, and a vertical alignment liquid crystal cell.

[0033] 〔4〕The laminate according to any one of 〔1〕 to 〔3〕, wherein,

[0034] The above-mentioned second liquid crystal cell is a liquid crystal cell capable of switching the in-plane phase difference of the above-mentioned second liquid crystal cell to 0 and λ / 2,

[0035] In a state where the in-plane phase difference of the above-mentioned second liquid crystal cell is λ / 2, the angle formed by the in-plane slow axis direction of the above-mentioned second liquid crystal cell and the absorption axis of the above-mentioned second polarizer is in the range of 45 ± 10°.

[0036] 〔5〕The laminate according to any one of 〔1〕 to 〔3〕, wherein,

[0037] The second liquid crystal cell described above is a liquid crystal cell having an in-plane retardation of λ / 2 and capable of controlling the direction of the in-plane slow axis.

[0038] The second liquid crystal cell described above is capable of controlling the in-plane slow axis within a range where the angle formed between the direction of the in-plane slow axis of the second liquid crystal cell and the absorption axis of the second polarizer is 45 ± 10° and within a range of 0 ± 10°.

[0039] 〔6〕A liquid crystal display device comprising the laminate according to any one of 〔1〕 to 〔5〕 above.

[0040] 〔7〕An in-vehicle display comprising the liquid crystal display device according to 〔6〕 above.

[0041] Advantages of the Invention

[0042] According to the present invention, it is possible to provide a laminate that, when applied as a component of a liquid crystal display device, enables viewing angle control of the obtained liquid crystal display device, has excellent light-shielding properties of the obtained liquid crystal display device, and further has excellent light resistance.

[0043] Furthermore, according to the present invention, it is also possible to provide a liquid crystal display device and an in-vehicle display using the above laminate. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic diagram showing one embodiment of the liquid crystal display device of the present invention.

[0045] Figure 2 is a cross-sectional schematic diagram showing one embodiment of the liquid crystal display device of the present invention.

[0046] Figure 3 is a cross-sectional schematic diagram showing one embodiment of the liquid crystal display device of the present invention.

[0047] Figure 4 is a cross-sectional schematic diagram showing the change in polarization state in the liquid crystal display device of the present invention.

[0048] Figure 5 is a cross-sectional schematic diagram showing the change in polarization state in the liquid crystal display device of the present invention.

[0049] Figure 6 is a cross-sectional schematic diagram showing the change in polarization state in the liquid crystal display device of the present invention.

[0050] Figure 7 is a cross-sectional schematic diagram showing the change in polarization state in the liquid crystal display device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0051] Hereinafter, the present invention will be described in detail.

[0052] The descriptions of the constituent elements described below may be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

[0053] The meanings of the respective descriptions in this specification are shown below.

[0054] In this specification, the numerical range indicated by "~" means the range including the numerical values described before and after "~" as the lower limit value and the upper limit value.

[0055] In this specification, parallel and orthogonal do not mean strictly parallel and orthogonal, but mean the range of ±5° from parallel or orthogonal. And, in this specification, when not otherwise specified, the polar angle means the angle formed with the normal direction of the thin film.

[0056] And, in this specification, the concepts of liquid crystal compositions and liquid crystal compounds also include substances that no longer exhibit liquid crystallinity through curing or the like.

[0057] And, in this specification, each component may be used alone with a substance corresponding to each component, or two or more may be used simultaneously. Here, regarding each component, when two or more substances are used simultaneously, unless otherwise specified, the content of the component means the total content of the substances used simultaneously.

[0058] And, in this specification, "(meth)acrylate" is an expression indicating "acrylate" or "methacrylate", "(meth)acrylic acid" is an expression indicating "acrylic acid" or "methacrylic acid", and "(meth)acryloyl" is an expression indicating "acryloyl" or "methacryloyl".

[0059] In the present invention, the refractive indices nx and ny are the refractive indices in the in-plane direction of the optical component. Usually, nx is the refractive index in the slow axis direction, and ny is the refractive index in the fast axis direction (i.e., the direction orthogonal to the slow axis). And, nz is the refractive index in the thickness direction. nx, ny, and nz can be measured, for example, by using an Abbe refractometer (NAR-4T, manufactured by ATAGO CO., LTD.) and using a sodium lamp (λ = 589 nm) as the light source. And, when measuring the wavelength dependence, it can be measured by using a multi-wavelength Abbe refractometer DR-M2 (manufactured by ATAGO CO., LTD.) in combination with an interference filter. And, the values in the polymer handbook (JOHN WILEY&SONS, INC) and the product catalogs of various optical films can also be used.

[0060] In this specification, Re(λ) and Rth(λ) respectively represent the in-plane phase difference and the thickness direction phase difference at wavelength λ, and are represented by the following formulas (1) and (2) using the refractive indices nx, ny, and nz and the film thickness d (μm).

[0061] Equation (1): Re(λ) = (nx - ny) × d × 1000 (nm)

[0062] Equation (2): Rth(λ) = ((nx + ny) / 2 - nz) × d × 1000 (nm)

[0063] When there is no special description, the wavelength λ is set to 550 nm.

[0064] The slow axis orientation, Re(λ), and Rth(λ) can be measured using, for example, AxoScan OPMF-1 (manufactured by Opto Science, Inc.).

[0065] In this specification, Δnd refers to the phase difference generated by a layer in which a rod-like liquid crystalline compound or a discotic liquid crystalline compound is twisted and oriented with the thickness direction as the axis, and is represented by the product of the thickness d of the liquid crystal layer and the birefringence Δn of the liquid crystal. Also, the twist angle of the liquid crystalline compound from one surface to the other surface of the layer in which the liquid crystalline compound is twisted and oriented is also referred to as the twist angle of the liquid crystalline compound.

[0066] In addition, when there is no special description, Δn is set to the value at a wavelength of 550 nm.

[0067] <Stacked body>

[0068] The stacked body of the present invention is a stacked body having a first light absorption anisotropic layer, a first polarizer, a first liquid crystal cell, a second polarizer, a second liquid crystal cell, and a second light absorption anisotropic layer in this order.

[0069] In addition, the absorption axis of the first polarizer is orthogonal to the absorption axis of the second polarizer.

[0070] Moreover, the first light absorption anisotropic layer and the second light absorption anisotropic layer contain a dichroic substance. Here, the angle θ1 formed by the transmittance central axis of the first light absorption anisotropic layer and the normal direction of the surface of the first light absorption anisotropic layer is 0 to 45°, and the angle θ2 formed by the transmittance central axis of the second light absorption anisotropic layer and the normal direction of the surface of the second light absorption anisotropic layer is 0 to 45°.

[0071] The stacked body of the present invention is used as a component of a liquid crystal display device and constitutes the liquid crystal display device of the present invention.

[0072] In Figure 1 shows a schematic diagram showing one embodiment of a liquid crystal display device using the stacked body of the present invention.

[0073] Figure 1 The liquid crystal display device 500 shown has a stacked body 10 and a surface light source 400 in this order from the visually recognizable side. In addition, inFigure 1 In [reference], the visual recognition side refers to the side with an arrow marked in the front visual recognition direction 1.

[0074] In Figure 1 the laminate 10 successively includes a first light absorption anisotropic layer 102a, a liquid crystal panel 300, a second liquid crystal cell 200, and a second light absorption anisotropic layer 102b. The liquid crystal panel 300 successively includes a first polarizer 304a, a first liquid crystal cell 302, and a second polarizer 304b from the visual recognition side.

[0075] In Figure 1 the front visual recognition direction 1 is parallel to the z-axis direction. Also, the first visual recognition direction 2 is a direction parallel to the zx plane, and the second visual recognition direction 3 is a direction parallel to the yz plane.

[0076] Figure 2 is a schematic cross-sectional view of a liquid crystal display device 500 of a plane (a plane parallel to the zx plane) including Figure 1 the front visual recognition direction 1 and the first visual recognition direction 2 in [reference].

[0077] As Figure 2 shown, in the liquid crystal display device 500, the absorption axis 32a of the first polarizer is orthogonal to the absorption axis 32b of the second polarizer. Also, the absorption axis 32a of the first polarizer is parallel to the depth direction of the paper surface of Figure 2 , and the absorption axis 32b of the second polarizer is orthogonal to the depth direction of the paper surface of Figure 2 .

[0078] Also, the angle θ1 formed by the transmittance central axis 12a of the first light absorption anisotropic layer 102a and the normal direction of the surface of the first light absorption anisotropic layer 102a is 0°. And the angle θ2 formed by the transmittance central axis 12b of the second light absorption anisotropic layer 102b and the normal direction of the surface of the second light absorption anisotropic layer 102b is 0°.

[0079] In Figure 1 and Figure 2 the shown liquid crystal display device 500, by controlling the alignment direction of the liquid crystalline compound in each pixel of the first liquid crystal cell 302, the amount of light transmitted through each pixel of the liquid crystal panel 300 is adjusted to display an image.

[0080] Also, in Figure 1 and Figure 2In the liquid crystal display device 500 shown, the first liquid crystal cell 302 and the second liquid crystal cell 200 are of the twisted nematic (TN: Twisted Nematic) type. Generally, in a TN-type liquid crystal cell, in a state where no voltage is applied, the liquid crystalline compound is twisted and oriented about the thickness direction of the first liquid crystal cell 302 or the second liquid crystal cell 200.

[0081] Generally, in the TN-type liquid crystal cell as described above, in a state where no voltage is applied, the orientation direction of the liquid crystalline compound rotates by 90° from one surface of the liquid crystal cell to the other surface of the liquid crystal cell. And generally, linearly polarized light incident on the TN-type liquid crystal cell in a state where no voltage is applied rotates by 90° and exits from the TN-type liquid crystal cell. And generally, linearly polarized light incident on the TN-type liquid crystal cell in a state where a voltage is applied exits from the TN-type liquid crystal cell while maintaining its polarization state.

[0082] Therefore, in a liquid crystal panel in which a normal TN-type liquid crystal cell is disposed between two polarizers in an orthogonal Nicol configuration, in a state where no voltage is applied, a white display that transmits light is achieved.

[0083] In Figure 2 In the liquid crystal display device 500 shown, the displayed image can be visually recognized from the front visual recognition direction 1, but the displayed image cannot be visually recognized in the first visual recognition direction 2 at a position inclined to the right side of the paper surface from the front visual recognition direction 1 at an azimuth angle orthogonal to the absorption axis of the first polarizer 304a. That is, the light emitted from the liquid crystal display device 500 in the first visual recognition direction 2 is blocked.

[0084] Hereinafter, the above principle will be described.

[0085] In addition, Figure 2 The change in the polarization state in the first visual recognition direction 2 shown is shown in Figure 4 and Figure 5 . In Figure 4 and Figure 5 , the hollow arrows indicate the transmitted polarized light components, and the directions shown between the respective layers indicate the polarization directions of the transmitted polarized light components. In addition, Figure 4 and Figure 5 The symbols of the respective structures shown are the same as those in Figure 1 and Figure 2 , and are in the same manner as Figure 1 and Figure 2 .

[0086] As will be described later, Figure 4 represents the change in the polarization state in a state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200, Figure 5The diagram shows a change in the polarization state when no voltage is applied to the first liquid crystal cell 302 and a voltage is applied to the second liquid crystal cell 200 .

[0087] First, use Figure 2 The state where no voltage is applied to the first liquid crystal unit 302 and the second liquid crystal unit 200 will be described (see also Figure 4 . ).

[0088] A portion of the light emitted from the surface light source 400 in the first visual recognition direction 2 is absorbed by the dichroic material contained in the second light-absorbing anisotropic layer 102b. At this time, the angle θ2 formed between the transmittance center axis 12b of the second light-absorbing anisotropic layer 102b and the normal direction of the surface of the second light-absorbing anisotropic layer 102b is 0°. Therefore, the polarization component in the direction perpendicular to the depth direction of the paper is absorbed by the dichroic material. Figure 2 The polarized light component in the depth direction of the paper is transmitted more.

[0089] The light transmitted through the second light absorption anisotropic layer 102b Figure 1 The polarized light component in the depth direction of the paper passes through the second liquid crystal cell 200 and its polarization direction is rotated 90 degrees. As a result, the polarized light component emitted from the second liquid crystal cell 200 becomes the same direction as the absorption axis 32b of the second polarizer 304b, and the polarized light component is absorbed by the second polarizer 304b.

[0090] Therefore, in a state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200 , light emitted in the first visual direction 2 is blocked.

[0091] Next, use Figure 2 The state in which no voltage is applied to the first liquid crystal unit 302 and a voltage is applied to the second liquid crystal unit 200 will be described (see also Figure 5 . ).

[0092] Similar to the above-mentioned state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200, in the second light absorption anisotropic layer 102b, Figure 2 The polarized light component in the depth direction of the paper is transmitted more.

[0093] Here, when a voltage is applied to the second liquid crystal cell 200, the polarization state of the light passing through the second liquid crystal cell 200 is maintained. Therefore, the polarization component of the light passing through the second liquid crystal cell 200 remains Figure 2 The light incident on the first liquid crystal unit 302 is not absorbed by the second polarizer 304b. Figure 2The direction of the polarization component in the depth direction of the paper surface is rotated by 90° and incident on the first polarizer 304a, and then transmitted through the first polarizer 304a. Here, the polarization direction of the polarization component emitted from the first polarizer 304a is a direction orthogonal to the depth direction of the paper surface.

[0094] In this way, the polarization component emitted from the first polarizer 304a is absorbed by the dichroic substance of the first light absorption anisotropic layer 102a. This is because the angle θ1 formed by the transmittance central axis 12a of the first light absorption anisotropic layer 102a and the normal direction of the surface of the first light absorption anisotropic layer 102a is 0°, and it is easy to absorb the polarization component in the direction orthogonal to the depth direction of the paper surface.

[0095] Therefore, even in the state where no voltage is applied to the first liquid crystal cell 302 and a voltage is applied to the second liquid crystal cell 200, the light emitted toward the first visual recognition direction 2 is blocked.

[0096] In addition, in the above, the characteristics in the first visual recognition direction 2 at a position inclined to the right side of the paper surface from the front visual recognition direction 1 at an azimuth angle orthogonal to the absorption axis of the first polarizer 304a were described. However, when visually recognizing in the visual recognition direction at a position inclined to the left side of the paper surface from the front visual recognition direction 1 at an azimuth angle orthogonal to the absorption axis of the first polarizer 304a, the same mechanism as when visually recognizing from the above first visual recognition direction 2 occurs, and the light is blocked.

[0097] That is, in Figure 2 In the liquid crystal display device 500 shown, when visually recognizing the liquid crystal display device 500 from an inclined direction in the direction orthogonal to the absorption axis of the first polarizer 304a, the image displayed on the liquid crystal display device 500 is shielded from light.

[0098] Next, the case of visually recognizing the liquid crystal display device 500 from the second visual recognition direction 3 is described. Figure 1 The cross-sectional schematic diagram of the liquid crystal display device 500 shown in

[0099] Figure 3 is a cross-sectional schematic diagram of the liquid crystal display device 500 including the plane (the plane parallel to the yz plane) of the front visual recognition direction 1 and the second visual recognition direction 3 in Figure 1 The liquid crystal display device 500 shown in Figure 3 is the same as the liquid crystal display devices shown in Figure 1 and Figure 2 except that the direction shown in the cross-section is different. Therefore, Figure 3 the symbols of the respective structures shown in Figure 1 and Figure 2 are the same as those in Figure 1 and Figure 2In the same manner. Additionally, the directions of the absorption axes 32a of the first polarizer 304a and 32b of the second polarizer 304b are each rotated by 90° from the Figure 2 directions shown.

[0100] In Figure 3 the liquid crystal display device 500 shown, the image being displayed can be visually recognized from the front viewing direction 1, and the visibility of the displayed image can be switched at the second viewing direction 3 at a position inclined to the right side of the paper surface from the front viewing direction 1 at an azimuth angle parallel to the absorption axis of the first polarizer 304a. That is, it is possible to switch whether the light emitted from the liquid crystal display device 500 toward the second viewing direction 3 is blocked.

[0101] Hereinafter, the above principle will be described.

[0102] Additionally, the change in the polarization state in the second viewing direction 3 shown in Figure 3 is shown in Figure 6 and Figure 7 . In Figure 6 and Figure 7 , the hollow arrows indicate the polarized light components transmitted in the second viewing direction 3, and the directions shown between the layers indicate the polarization directions of the transmitted polarized light components. Additionally, Figure 6 and Figure 7 the symbols of the respective structures shown are the same as those in Figures 1 to 3 and are in the same manner as Figures 1 to 3 .

[0103] As will be described later, Figure 6 represents the change in the polarization state in a state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200, Figure 7 and represents the change in the polarization state in a state where no voltage is applied to the first liquid crystal cell 302 and a voltage is applied to the second liquid crystal cell 200.

[0104] First, the state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200 will be described using Figure 3 (see also Figure 6 ).

[0105] A part of the light emitted from the surface light source 400 toward the second viewing direction 3 is absorbed by the dichroic substance contained in the second light absorption anisotropic layer 102b. At this time, in the same manner as in Figure 2 , Figure 3 more polarized light components in the depth direction of the paper surface of

[0106] are transmitted. Figure 3The polarization component in the depth direction of the paper surface passes through the second liquid crystal cell 200, and its polarization direction is rotated by 90°. In this way, the polarization component emitted from the second liquid crystal cell 200 becomes a direction orthogonal to the absorption axis 32b of the second polarizer 304b, and transmits through the second polarizer 304b.

[0107] The direction of the polarization component that has transmitted through the second polarizer 304b is rotated by 90° through the first liquid crystal cell 302 and enters the first polarizer 304a, and transmits through the first polarizer 304a. Here, the polarization direction of the polarization component emitted from the first polarizer 304a is the depth direction of the paper surface.

[0108] The polarization component emitted from the first polarizer 304a enters the first light absorption anisotropic layer 102a. However, since the polarization direction of the polarization component is the depth direction of the paper surface and is a direction orthogonal to the transmittance central axis 12a, it is not absorbed by the dichroic substance contained in the first light absorption anisotropic layer 102a and transmits through.

[0109] Therefore, in a state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200, the light emitted toward the second visual recognition direction 3 transmits through.

[0110] Next, Figure 3 A state where no voltage is applied to the first liquid crystal cell 302 and a voltage is applied to the second liquid crystal cell 200 will be described (see also Figure 7 .).

[0111] Similar to the state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200, in the second light absorption anisotropic layer 102b, Figure 3 more of the polarization component in the depth direction of the paper surface transmits through.

[0112] Here, when a voltage is applied to the second liquid crystal cell 200, the polarization state of the light transmitted through the second liquid crystal cell 200 can be maintained. In this way, the polarization direction of the polarization component emitted from the second liquid crystal cell 200 becomes Figure 3 the depth direction of the paper surface, so it becomes the same direction as the absorption axis 32b of the second polarizer 304b, and the polarization component is absorbed by the second polarizer 304b.

[0113] Therefore, in a state where no voltage is applied to the first liquid crystal cell 302 and a voltage is applied to the second liquid crystal cell 200, the light emitted toward the second visual recognition direction 3 is blocked.

[0114] In addition, in the above description, the characteristics in the third viewing direction 3 at a position inclined to the right side of the paper surface from the front viewing direction 1 at an azimuth angle parallel to the absorption axis of the first polarizer 304a were described. However, when viewing in the viewing direction at a position inclined to the left side of the paper surface from the front viewing direction 1 at an azimuth angle parallel to the absorption axis of the first polarizer 304a, the same mechanism as when viewing in the above-described third viewing direction 3 occurs.

[0115] In addition, the light emitted in the front viewing direction 1 is not blocked and is emitted. The reason therefor will be described below. Here, Figure 2 a state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200 will be described.

[0116] First, the front viewing direction 1 is parallel to the transmittance central axis 12b of the second light absorption anisotropic layer 102b. Therefore, the light incident on the second polarizer 304b includes Figure 2 a polarization component in the depth direction of the paper surface and a polarization component in a direction Figure 2 orthogonal to the depth direction of the paper surface. Among the light incident on the second polarizer 304b in the front viewing direction 1, the polarization component in the direction parallel to the absorption axis 32b of the second polarizer 304b is absorbed, but the polarization component in the orthogonal direction transmits through the second polarizer 304b. Next, the polarization component incident on the first liquid crystal cell 302 passes through the first liquid crystal cell 302 and its polarization direction is rotated by 90°. Therefore, it transmits through the first polarizer 304a. And since the front viewing direction 1 is parallel to the transmittance central axis 12a of the first light absorption anisotropic layer 102a, the polarization component emitted in the front viewing direction 1 is not absorbed by the first light absorption anisotropic layer 102a and is emitted.

[0117] Therefore, in a state where no voltage is applied to the first liquid crystal cell 302 and the second liquid crystal cell 200, the light emitted in the front viewing direction 1 is transmitted.

[0118] In addition, even in a state where a voltage is applied to the second liquid crystal cell 200, only the polarization direction does not change. Therefore, the light incident on the second polarizer 304b includes Figure 2 a polarization component in the depth direction of the paper surface and a polarization component in a direction Figure 2 orthogonal to the depth direction of the paper surface. Therefore, the light emitted in the front viewing direction 1 is transmitted in the same manner as in the state where no voltage is applied to the second liquid crystal cell 200.

[0119] As described above, in the liquid crystal display device using the laminate of the present invention, towards Figure 1 and Figure 2Light emitted from the liquid crystal display device in the front visual recognition direction 1 is blocked regardless of whether a voltage is applied to the second liquid crystal cell 200. And, light emitted in the second visual recognition direction 3 of Figure 1 and Figure 3 can be switched between being blocked and emitted according to whether a voltage is applied to the second liquid crystal cell 200.

[0120] Here, in the liquid crystal display device using the laminate of the present invention, the light-shielding property of the obtained liquid crystal display device is excellent. Specifically, in the state where a voltage is applied to the second liquid crystal cell 200, the light in the second visual recognition direction 3 of Figure 1 is not easily transmitted, and regardless of whether a voltage is applied to the second liquid crystal cell 200, the light in the first visual recognition direction 2 of Figure 1 is not easily transmitted.

[0121] The reason for the above is not necessarily clear, but the inventors of the present invention speculate as follows. In the laminate 10 of the present invention, the first light absorption anisotropic layer 102a is disposed on the side closest to the visual recognition side. In the liquid crystal panel 300, scattering such as a change in polarization state may occur. However, even in the case where such scattering occurs, since the light scattered by the first light absorption anisotropic layer 102a can be absorbed, it is considered that the light-shielding property of the obtained liquid crystal display device is excellent.

[0122] And, the laminate of the present invention has excellent light resistance.

[0123] The reason for the above is not necessarily clear, but the inventors of the present invention speculate as follows. As Figures 1 to 3 shown, in the laminate 10 of the present invention, the second light absorption anisotropic layer 102b is disposed on the side opposite to the side closest to the visual recognition side. Therefore, when external light irradiates the laminate, the external light is easily absorbed by other layers during the period until the external light reaches the second light absorption anisotropic layer 102b. Therefore, it is considered that the deterioration of the second light absorption anisotropic layer 102b caused by external light does not easily progress. As a result, the obtained liquid crystal display device has excellent light resistance.

[0124] In addition, Figures 1 to 3 The mode shown is one mode of the present invention, and the present invention is not limited to the above mode.

[0125] For example, if the stacking direction of the liquid crystal panel 300 in the laminate 10 is rotated by 90°, then in Figure 1 the first visual recognition direction 2, it can be switched between being blocked and emitted, and the light emitted in the second visual recognition direction 3 is blocked.

[0126] And, the first liquid crystal cell 302 and the second liquid crystal cell 200 can be liquid crystal cells of different modes, respectively.

[0127] Moreover, the angle θ1 formed by the transmittance central axis 12a of the first light absorption anisotropic layer 102a and the normal direction of the surface of the first light absorption anisotropic layer 102a only needs to be 0 to 45°, and the angle θ1 can be adjusted according to the direction in which the image is desired to be visually recognized. Moreover, the angle θ2 formed by the transmittance central axis 12b of the second light absorption anisotropic layer 102b and the normal direction of the surface of the second light absorption anisotropic layer 102b only needs to be 0 to 45°, and the angle θ2 can be adjusted according to the direction in which the image is desired to be visually recognized.

[0128] Hereinafter, the structures included in the laminate will be described. In addition, in Figures 1 to 3 the shown mode and the above mode, each structure included in the laminate can be changed as examples of the following structures, and the changed structures can also be combined.

[0129] [First light absorption anisotropic layer]

[0130] The first light absorption anisotropic layer in the laminate of the present invention contains a dichroic substance, and the angle θ1 formed by the transmittance central axis of the first light absorption anisotropic layer and the normal direction of the surface of the first light absorption anisotropic layer is 0 to 45°. In addition, the transmittance central axis generally coincides with the alignment direction of the dichroic substance.

[0131] As described above, the angle θ1 can be adjusted according to the direction in which the image is desired to be visually recognized. For example, when an anti-peeping function is given to the liquid crystal display device, it is preferable to set the transmittance in the front direction to be the maximum. In this case, the angle θ1 is preferably 0 to 10°.

[0132] Moreover, the transmittance central axis of the first light absorption anisotropic layer can be set to different directions according to the positions within the plane of the first light absorption anisotropic layer. For example, in an in-vehicle display with a curved display surface, in order to prevent the emitted light from any position from being reflected into the windshield or the like and enable the driver to appropriately visually recognize the display image, it is preferable to align the direction of the transmittance central axis of the first light absorption anisotropic layer with the curved surface for adjustment.

[0133] In addition, the above-mentioned transmittance central axis refers to the direction in which the transmittance is the highest when measuring the transmittance while changing the tilt angle (polar angle) and tilt direction (azimuth angle) with respect to the normal direction of the surface of the first light absorption anisotropic layer. When measuring the above-mentioned angle θ1, AxoScan OPMF-1 (manufactured by Opto Science, Inc.) is used. First, the direction of the azimuth angle of the tilt of the transmittance central axis is detected. In this azimuth angle direction, while variously changing the polar angle, the Mueller matrix is measured to derive the transmittance, and the direction (polar angle) with the highest transmittance is used as the direction of the transmittance central axis of the light absorption anisotropic layer. The direction of this polar angle is the angle formed by the transmittance central axis in the light absorption anisotropic layer and the normal direction of the light absorption anisotropic layer.

[0134] In addition, the transmittance central axis (polar angle) of the first light absorption anisotropic layer is measured at 15 arbitrarily selected sites on the first light absorption anisotropic layer, and the average of this polar angle is used as the transmittance central axis in the first light absorption anisotropic layer.

[0135] Moreover, in the present invention, when not specifically specified, light with a wavelength of 550 nm is used for these optical measurements.

[0136] The transmittance of light in the direction parallel to the transmittance central axis of the first light absorption anisotropic layer is preferably 50% or more, more preferably 70%. The upper limit of the transmittance is not particularly limited. For example, cases of 95% or less and 90% or less are common.

[0137] The transmittance in the direction tilted 30° from the transmittance central axis of the first light absorption anisotropic layer is preferably 30% or less, more preferably 15% or less. The lower limit of the transmittance is not particularly limited. For example, cases of 0.5% or more and 5% or more are common.

[0138] The first light absorption anisotropic layer in the present invention has a layer containing at least one dichroic substance (for example, a dichroic pigment). Hereinafter, as an example of the above-mentioned dichroic substance, the dichroic pigment will be described.

[0139] (Dichroic pigment)

[0140] The dichroic substance contained in the first light absorption anisotropic layer of the present invention is not particularly limited as long as it is a substance that exhibits dichroism, and examples thereof include dichroic pigments, dichroic azo pigment compounds, ultraviolet absorbing substances, infrared absorbing substances, nonlinear optical substances, carbon nanotubes, anisotropic metal nanoparticles, and inorganic substances.

[0141] The first light absorption anisotropic layer can also contain two or more dichroic substances. For example, it preferably contains a cyan pigment that exhibits dichroism in the red wavelength region, a magenta pigment that exhibits dichroism in the green wavelength region, and a yellow pigment that exhibits dichroism in the blue wavelength region. If multiple dichroic substances are included, the color can be neutralized and the viewing angle control effect can be exhibited over the entire visible light wavelength region.

[0142] In addition, a dichroic substance refers to a substance that exhibits dichroism, and dichroism refers to the property of having different absorbances depending on the polarization direction.

[0143] The degree of orientation of the dichroic substance at a wavelength of 550 nm is preferably 0.95 or more. If the degree of orientation of the dichroic substance is 0.95 or more, the transmittance in the absorption axis direction (i.e., the direction in which light is desired to be transmitted) can be increased. Also, from the aspect of being able to neutralize the color, the degree of orientation of the dichroic substance at a wavelength of 420 nm is preferably 0.93 or more.

[0144] The thickness of the first light absorption anisotropic layer is not particularly limited, but from the viewpoint of flexibility, it is preferably 100 to 8000 nm, more preferably 300 to 5000 nm.

[0145] As the dichroic substance, a dichroic pigment is preferred, and a dichroic azo pigment compound is more preferred.

[0146] In the present invention, a dichroic azo pigment compound refers to an azo pigment compound having different absorbances depending on the direction.

[0147] The dichroic azo pigment compound may or may not exhibit liquid crystallinity.

[0148] When the dichroic azo pigment compound exhibits liquid crystallinity, it can exhibit either a nematic liquid crystal phase or a smectic liquid crystal phase. The temperature range in which the liquid crystal phase is exhibited is preferably room temperature (about 20 °C to 28 °C) to 300 °C, and more preferably 50 to 200 °C from the viewpoints of operability and manufacturing applicability.

[0149] In the present invention, from the viewpoint of better press resistance, it is preferred that the dichroic azo pigment compound contained in the light absorption anisotropic layer forming composition used when forming the first light absorption anisotropic layer described below has a crosslinkable group.

[0150] Specific examples of the crosslinkable group include (meth)acryloyl, epoxy group, oxetanyl, and styryl, etc. Among them, (meth)acryloyl is preferred.

[0151] Examples of the preferred dichroic azo pigment compounds used in the present invention include a first dichroic azo pigment compound, a second dichroic azo pigment compound, and a third dichroic azo pigment compound.

[0152] The first dichroic azo pigment compound refers to a dichroic azo pigment compound having a maximum absorption wavelength in the range of 560 nm or more and 700 nm or less. Further, the second dichroic azo pigment compound is a dichroic azo pigment compound having a maximum absorption wavelength in the range of 455 nm or more and less than 560 nm. The third dichroic azo pigment compound refers to a dichroic azo pigment compound having a maximum absorption wavelength in the range of 380 nm or more and 455 nm or less.

[0153] Specific examples of the first dichroic azo pigment compound, the second dichroic azo pigment compound, and the third dichroic azo pigment compound include, for example, the compounds described in paragraphs

[0161] to

[0171] of International Publication No. 2022 / 138548, the compounds described in paragraphs

[0172] to

[0180] of International Publication No. 2022 / 138548, and the compounds described in paragraphs

[0183] to

[0206] of International Publication No. 2022 / 138548, respectively.

[0154] Relative to the total solid content mass of the first light absorption anisotropic layer, the content of the dichroic substance is preferably 1 to 30% by mass, more preferably 5 to 25% by mass, and still more preferably 10 to 20% by mass.

[0155] Further, in the first light absorption anisotropic layer of the present invention, due to the reason that the degree of orientation becomes higher, it is preferable that the dichroic substances contained in the light absorption anisotropic layer form an alignment structure.

[0156] Here, the alignment structure means a state in which dichroic substances aggregate to form an aggregate in the light absorption anisotropic layer, and the molecules of the dichroic substances are periodically arranged in the aggregate.

[0157] The alignment structure may be formed only by dichroic substances, or may be formed by a liquid crystalline compound and dichroic substances described later. Further, the alignment structure may be formed by one kind of dichroic substance, or may be formed by a plurality of kinds of dichroic substances.

[0158] In the alignment structure, the structure formed by a certain kind of dichroic substance and the structure formed by other kinds of dichroic substances may coexist in the light absorption anisotropic layer.

[0159] Further, in the case where the light absorption anisotropic layer contains a plurality of dichroic substances, an alignment structure may be formed by all types of dichroic substances among the plurality of dichroic substances contained in the light absorption anisotropic layer, or an alignment structure may be formed by some types of dichroic substances.

[0160] In the present invention, for the reason that the degree of orientation of the first light absorption anisotropic layer becomes higher, when observing a cross section of the first light absorption anisotropic layer with a scanning transmission electron microscope, when the length of the major axis of the alignment structure is set to L and the length of the minor axis is set to D, an alignment structure satisfying L≥240 nm is preferably observed 3 or more times per 40 μm 2 more preferably 3 to 15 times, and still more preferably 3 to 10 times.

[0161] Here, the cross-sectional observation based on a scanning transmission electron microscope (Scanning Transmission Electron Microscope) (hereinafter, also simply referred to as "STEM") is specifically performed as follows.

[0162] First, the first light absorption anisotropic layer is cut with an ultramicrotome to produce an ultrathin section having a thickness of 100 nm in the film thickness direction.

[0163] Next, the ultrathin section is placed on a grid with a carbon support film for STEM observation.

[0164] Then, it is set in a scanning transmission electron microscope together with the grid, and the cross section is observed at an electron beam acceleration voltage of 30 kV.

[0165] Further, the length L of the major axis and the length D of the minor axis of the alignment structure are specifically measured as follows.

[0166] First, as described above, an image obtained by observing and photographing a cross section of the first light absorption anisotropic layer with STEM is analyzed to produce a frequency histogram, and the frequency having the maximum frequency and the standard deviation of the frequency distribution are obtained.

[0167] Next, the frequency that is 1.3 times the standard deviation from the frequency having the maximum frequency toward the dark side is set as a threshold value.

[0168] Next, an image obtained by binarizing the brightness is produced using the threshold value, and a portion having a major axis of 30 nm or more in the binarized dark region is extracted as the alignment structure.

[0169] Moreover, each of the extracted alignment structures is approximated by an ellipse, the length of the major axis of the approximated ellipse is set as the length L of the major axis of the alignment structure, and the length of the minor axis of the approximated ellipse is set as the length D of the minor axis of the alignment structure.

[0170] The length L of the major axis and the length D of the minor axis of this arrangement structure can be measured using well-known image processing software. As the image processing software, for example, the image processing software "ImageJ" can be cited.

[0171] (Liquid crystalline compound)

[0172] The first light absorption anisotropic layer is also preferably formed using a liquid crystal composition containing a dichroic substance and a liquid crystalline compound. Therefore, the first light absorption anisotropic layer preferably contains a component derived from the liquid crystalline compound.

[0173] By forming the first light absorption anisotropic layer using the above liquid crystal composition, precipitation of the dichroic substance can be suppressed while the dichroic substance is oriented with a high degree of orientation.

[0174] As the liquid crystalline compound, either a low-molecular liquid crystalline compound or a high-molecular liquid crystalline compound can be used, and it is also preferable to use both simultaneously. Here, the "low-molecular liquid crystalline compound" refers to a liquid crystalline compound that does not have a repeating unit in its chemical structure. And the "high-molecular liquid crystalline compound" refers to a liquid crystalline compound that has a repeating unit in its chemical structure.

[0175] As the low-molecular liquid crystalline compound, it can be either a compound showing a nematic liquid crystal phase or a compound showing a smectic liquid crystal phase, but from the viewpoint of improving the degree of orientation, a compound showing a smectic liquid crystal phase is preferable. For example, the liquid crystalline compounds described in Japanese Unexamined Patent Application Publication No. 2013-228706 can be cited.

[0176] As the high-molecular liquid crystalline compound, for example, the thermotropic liquid crystalline polymer described in Japanese Unexamined Patent Application Publication No. 2011-237513 can be cited. And from the viewpoint of excellent strength (especially the bending resistance of the film), the high-molecular liquid crystalline compound preferably has a repeating unit having a crosslinkable group at the end. As the crosslinkable group, for example, the polymerizable groups described in paragraphs

[0040] to

[0050] of Japanese Unexamined Patent Application Publication No. 2010-244038 can be cited. Among these, from the viewpoints of improving reactivity and synthesis applicability, acryloyl, methacryloyl, epoxy group, oxetanyl, and styryl are preferable, and acryloyl and methacryloyl are more preferable.

[0177] When the first light absorption anisotropic layer contains a high-molecular liquid crystalline compound, the high-molecular liquid crystalline compound preferably forms a nematic liquid crystal phase. The temperature range showing a nematic liquid crystal phase is preferably room temperature (23 °C) to 450 °C, and from the viewpoint of processing or manufacturing applicability, it is preferably 50 to 400 °C.

[0178] With respect to 100 parts by mass of the dichroic substance, the content of the component derived from the liquid crystalline compound in the first light absorption anisotropic layer is preferably 25 to 2000 parts by mass, more preferably 100 to 1300 parts by mass, and still more preferably 200 to 900 parts by mass. By setting the content of the liquid crystalline compound within the above range, the degree of orientation of the dichroic substance is further improved.

[0179] It may contain a single liquid crystalline compound or two or more. In the case of containing two or more liquid crystalline compounds, the content of the component derived from the above liquid crystalline compounds refers to the total content of the liquid crystalline compounds.

[0180] (Additive)

[0181] The liquid crystal composition used in the formation of the first light absorption anisotropic layer may further contain additives such as a solvent, a vertical alignment agent, a surface modifier, a leveling agent, a polymerizable component, a polymerization initiator (e.g., a radical polymerization initiator), and a durability improver. The additives can be appropriately used well-known additives.

[0182] The laminate of the present invention may include other layers different from the first light absorption anisotropic layer and the layers described later. Among them, the other layer is a layer that is in direct contact with the first light absorption anisotropic layer or is in indirect contact with the first light absorption anisotropic layer via a layer different from the first light absorption anisotropic layer and the layers described later. Hereinafter, the other layers in direct or indirect contact with the first light absorption anisotropic layer will be described.

[0183] (Substrate layer)

[0184] The laminate of the present invention may include a substrate layer as the other layer.

[0185] The substrate layer is not particularly limited, but a transparent film or sheet is preferred, and well-known transparent resin films, transparent resin plates, transparent resin sheets, glass, etc. can be used. As the transparent resin film, a cellulose acylate film (e.g., a triacetate cellulose film, a diacetate cellulose film, a butyryl acetate cellulose film, a propionyl acetate cellulose film), a polyethylene terephthalate film, a polyethersulfone film, a polyacrylic resin film, a polyurethane resin film, a polyester film, a polycarbonate film, a polysulfone film, a polyether film, a polymethylpentene film, a polyether ketone film, a (meth)acrylonitrile film, etc. can be used.

[0186] Among them, a cellulose acylate film having high transparency, little optical birefringence, easy to manufacture, and usually used as a protective film for a polarizer is preferred, and a triacetate cellulose film is particularly preferred.

[0187] The thickness of the transparent resin film is preferably 20 μm to 100 μm.

[0188] (Alignment film)

[0189] The laminate of the present invention may have an alignment film as another layer between the substrate layer and the first light-absorbing anisotropic layer.

[0190] The alignment film can be any layer as long as it can make the dichroic substance (liquid crystalline compound) have a desired alignment state on the alignment film.

[0191] For example, a film formed of a polyfunctional acrylate compound and polyvinyl alcohol can be used. Polyvinyl alcohol is particularly preferred.

[0192] The alignment film can be a photo-alignment film. In addition, by irradiating a photo-alignment film containing an azo compound or a cinnamoyl compound from an oblique direction with UV light, the dichroic substance can be aligned obliquely with respect to the normal direction of the thin film.

[0193] (Barrier layer)

[0194] The laminate of the present invention may include a barrier layer as another layer.

[0195] Here, the barrier layer is also called a gas barrier layer (oxygen barrier layer), and has a function of protecting the first light-absorbing anisotropic layer from gases such as oxygen in the atmosphere, moisture, or compounds contained in adjacent layers.

[0196] Regarding the barrier layer, for example, reference can be made to paragraphs

[0014] to

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

[0042] to

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

[0045] to

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

[0010] to

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

[0021] to

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

[0197] (Refractive index adjustment layer)

[0198] In the first light-absorbing anisotropic layer, internal reflection caused by the high refractive index of the first light-absorbing anisotropic layer sometimes becomes a problem. In this case, a refractive index adjustment layer can be used. The refractive index adjustment layer is preferably a layer configured to be in contact with the first light-absorbing anisotropic layer and used for so-called index matching. The in-plane average refractive index of the refractive index adjustment layer at a wavelength of 550 nm is preferably 1.55 or more and 1.70 or less.

[0199] (Method for forming the first light-absorbing anisotropic layer)

[0200] The method for forming the first light absorption anisotropic layer is not particularly limited. For example, a method including the following steps in sequence can be cited: a step of forming a coating film by coating a composition for forming a light absorption anisotropic layer (hereinafter, also referred to as "coating film forming step"); and a step of aligning the liquid crystalline component or dichroic substance contained in the coating film (hereinafter, also referred to as "alignment step").

[0201] In addition, the liquid crystalline component not only includes the above-mentioned liquid crystalline compound, but also includes a dichroic substance having liquid crystallinity when the dichroic substance has liquid crystallinity.

[0202] - Coating film forming step -

[0203] The coating film forming step is a step of forming a coating film by coating a composition for forming a light absorption anisotropic layer.

[0204] By using a composition for forming a light absorption anisotropic layer containing a solvent or a composition for forming a light absorption anisotropic layer which is made into a liquid material such as a molten liquid by heating etc. of the composition for forming a light absorption anisotropic layer, it is easy to coat the composition for forming a light absorption anisotropic layer.

[0205] As a coating method of the composition for forming a light absorption anisotropic layer, specifically, for example, 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, spraying method and inkjet method etc. can be cited.

[0206] - Alignment step -

[0207] The alignment step is a step of aligning the liquid crystalline component contained in the coating film. Thereby, the first light absorption anisotropic layer can be obtained.

[0208] The alignment step may have a drying treatment. By the drying treatment, components such as a solvent can be removed from the coating film. The drying treatment can be carried out by a method of leaving the coating film at room temperature for a specified time (for example, natural drying), or can be carried out by a method of heating and / or blowing air.

[0209] Here, sometimes the liquid crystalline component contained in the composition for forming a light absorption anisotropic layer is aligned by the above-mentioned coating film forming step or drying treatment. For example, in a manner where the composition for forming a light absorption anisotropic layer is prepared as a coating liquid containing a solvent, by drying the coating film to remove the solvent from the coating film, a coating film having light absorption anisotropy (that is, the first light absorption anisotropic layer) can be obtained.

[0210] When the drying treatment is carried out at a temperature above the temperature at which the liquid crystalline component contained in the coating film changes from the liquid crystal phase to the isotropic phase, the heat treatment described later may not be carried out.

[0211] From the aspect of manufacturing applicability and the like, the transition temperature at which the liquid crystalline component contained in the coating film changes from the liquid crystal phase to the isotropic phase is preferably 10 to 250°C, more preferably 25 to 190°C. If the transition temperature is 10°C or higher, cooling treatment and the like for reducing the temperature to the temperature range where the liquid crystal phase is exhibited are not required, so it is preferred. Further, if the transition temperature is 250°C or lower, even when heated to the isotropic phase for the purpose of suppressing orientation defects, high temperature is not required, and waste of thermal energy, deformation and deterioration of the substrate, etc. can be reduced, so it is preferred.

[0212] The orientation step preferably includes a heat treatment. Thereby, the liquid crystalline component contained in the coating film can be oriented, and thus the coating film after the heat treatment can be suitably used as the light absorption anisotropic layer.

[0213] From the aspect of manufacturing applicability and the like, the heat treatment is preferably 10 to 250°C, more preferably 25 to 190°C. Further, the heating time is preferably 1 to 300 seconds, more preferably 1 to 60 seconds.

[0214] The orientation 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 around room temperature (20 to 25°C). Thereby, the orientation of the liquid crystalline component contained in the coating film can be fixed. The cooling method is not particularly limited and can be implemented by a known method.

[0215] -Other steps-

[0216] The method for forming the first light absorption anisotropic layer may include a step of curing the first light absorption anisotropic layer (hereinafter, also referred to as the "curing step") after the above-mentioned orientation step.

[0217] For example, when the compound contained in the first light absorption anisotropic layer has a crosslinkable group (polymerizable group), the curing step is carried out by heating and / or light irradiation (exposure). Among them, from the viewpoint of productivity, it is preferred to carry out the curing step by light irradiation.

[0218] As the light source used in curing, various light sources such as infrared rays, visible light, or ultraviolet rays can be used, but ultraviolet rays are preferred. Further, when curing, ultraviolet rays can be irradiated while heating, or ultraviolet rays can be irradiated through a filter that transmits only a specific wavelength.

[0219] When exposure is carried out while heating, although the heating temperature during exposure also depends on the transition temperature of the liquid crystalline component contained in the liquid crystal film, it is preferably 25 to 140°C.

[0220] Furthermore, the exposure can be carried out in a nitrogen atmosphere. In the case of curing the liquid crystal film by radical polymerization, polymerization inhibition caused by oxygen can be reduced, so it is preferably carried out in a nitrogen atmosphere.

[0221] In addition, the first light absorption anisotropic layer can be, for example, a light absorption anisotropic layer that contains a dichroic pigment and a guest host liquid crystal material and can electrically drive the orientation direction of the dichroic pigment as described in Japanese Patent Application Laid-Open No. 2013-541727. In this case, the orientation direction of the dichroic pigment can be electrically switched.

[0222] [First polarizer]

[0223] The first polarizer included in the laminate of the present invention is not particularly limited, and a known polarizer (linear polarizer) can be used.

[0224] In addition, the absorption axis of the first polarizer is orthogonal to the absorption axis of the second polarizer described later.

[0225] For example, as a linear polarizer (absorption polarizer), a polarizer obtained by dyeing a dichroic substance on polyvinyl alcohol or other polymer resins and stretching it to make it horizontally oriented, and a polarizer that makes a dichroic substance horizontally oriented by utilizing the orientation property of liquid crystal can be cited.

[0226] Furthermore, the first polarizer can be a reflective polarizer or a laminate of an absorption polarizer and a reflective polarizer. A reflective polarizer is a polarizer that reflects one of the polarized lights and transmits the other polarized light. In addition, the reflective polarizer has a reflection axis and a transmission axis in the plane, but the reflection axis serves the same role as the absorption axis in a normal polarizer (absorption polarizer) in the sense of not transmitting the polarized light in that orientation. Therefore, in this specification, the reflection axis of the reflective polarizer can be replaced with the absorption axis.

[0227] [First liquid crystal cell]

[0228] The first liquid crystal cell included in the laminate of the present invention is disposed between the first polarizer and the second polarizer, and adjusts the amount of light transmitted through the liquid crystal panel composed of the first polarizer, the first liquid crystal cell, and the second polarizer.

[0229] The first liquid crystal cell is not particularly limited as long as it can adjust the amount of light transmitted through the liquid crystal panel, and a known liquid crystal cell can be used. The first liquid crystal cell generally has a plurality of regions capable of controlling the orientation direction of the liquid crystalline compound, and independently controls the orientation direction of the liquid crystalline compound in each region to adjust the amount of light transmitted through the region of the liquid crystal panel corresponding to each region.

[0230] The form of the first liquid crystal cell is not particularly limited, and known methods can be used. As the form of the first liquid crystal cell, in addition to the above-mentioned TN type liquid crystal cell, in-plane switching (IPS) type liquid crystal cells, vertical alignment (VA) type liquid crystal cells, and optically compensated bend (OCB) type liquid crystal cells can also be cited.

[0231] Moreover, the form of the first liquid crystal cell can be a super twisted nematic (STN) type liquid crystal cell having a twist angle of 180° or more, or a vertically aligned twisted nematic (VATN) type liquid crystal cell disclosed in Japanese Patent Laid-Open No. 10-123576, in which rod-shaped liquid crystalline molecules are substantially vertically aligned when no voltage is applied, and the liquid crystal layer is twisted and aligned at 60 to 120° in the state where a voltage is applied.

[0232] Among them, the first liquid crystal cell is preferably selected from the group including TN type liquid crystal cells, IPS type liquid crystal cells, and VA type liquid crystal cells.

[0233] In a TN type liquid crystal cell, rod-shaped liquid crystalline molecules are substantially horizontally aligned when no voltage is applied, and are further twisted and aligned at 60 to 120° in the thickness direction. TN type liquid crystal cells are most commonly used in color thin film transistor (TFT) liquid crystal display devices and are described in many documents.

[0234] In a VA type liquid crystal cell, rod-shaped liquid crystalline molecules are substantially vertically aligned when no voltage is applied. In addition to (1) a narrow sense VA type liquid crystal cell (described in Japanese Patent Laid-Open No. 2-176625) in which rod-shaped liquid crystalline molecules are substantially vertically aligned when no voltage is applied and are substantially horizontally aligned when a voltage is applied, the VA type liquid crystal cell also includes (2) an (MVA type) liquid crystal cell in which the VA type is multi-domainized to expand the viewing angle (described in SID97, Digest of tech. Papers (Proceedings) 28 (1997) 845), (3) a liquid crystal cell of a type (n-ASM type) in which rod-shaped liquid crystalline molecules are substantially vertically aligned when no voltage is applied and are twisted multi-domain aligned when a voltage is applied (described in the preprint collection 58-59 (1998) of the Japanese Liquid Crystal Symposium), and (4) a SURVIVAL type liquid crystal cell (published in LCD International 98). And it can be any one of PVA (Patterned Vertical Alignment) type, optical alignment type, and PSA (Polymer-Sustained Alignment) type. For their detailed contents, there are detailed descriptions in Japanese Patent Laid-Open No. 2006-215326 and Japanese Patent Publication No. 2008-538819.

[0235] In an IPS type liquid crystal cell, rod-shaped liquid crystalline molecules are substantially parallel to the substrate. By applying a voltage between electrodes, an electric field parallel to the substrate surface is generated, and thus the liquid crystal molecule plane responds. The IPS type liquid crystal cell becomes black display in a state where no voltage is applied, and the absorption axes of the upper and lower pair of polarizers are orthogonal. Methods for reducing light leakage during black display in an inclined direction and improving the viewing angle using an optical compensation film are disclosed in Japanese Patent Laid-Open No. 10-54982, Japanese Patent Laid-Open No. 11-202323, Japanese Patent Laid-Open No. 9-292522, Japanese Patent Laid-Open No. 11-133408, Japanese Patent Laid-Open No. 11-305217, Japanese Patent Laid-Open No. 10-307291, etc.

[0236] [Second polarizer]

[0237] The second polarizer included in the laminate of the present invention is not particularly limited, and a known polarizer (linear polarizer) can be used.

[0238] In addition, the absorption axis of the first polarizer is orthogonal to the absorption axis of the second polarizer.

[0239] Examples and preferred modes of the second polarizer are the same as those of the first polarizer, and thus the description is omitted.

[0240] [Second liquid crystal cell]

[0241] In the laminate of the present invention, the second liquid crystal cell included is disposed between the second polarizer and the second light absorption anisotropic layer, and controls the polarization state of the polarized light transmitted through the second liquid crystal cell.

[0242] The second liquid crystal cell is not particularly limited as long as it can control the polarization state of the polarized light transmitted through the second liquid crystal cell, and a known liquid crystal cell can be used.

[0243] The second liquid crystal cell may have a plurality of regions capable of controlling the orientation direction of the liquid crystalline compound. In this case, the orientation direction of the liquid crystalline compound in each region can be controlled independently to adjust the polarization state of the polarized light transmitted through each region. When the second liquid crystal cell has a plurality of regions capable of controlling the orientation direction of the liquid crystalline compound, the orientation direction of the liquid crystalline compound in only a specific region can also be controlled, so that it is possible to switch between blocking and emitting the light emitted from the region of the liquid crystal display device corresponding to the above specific region.

[0244] In addition, the second liquid crystal cell may not have a plurality of regions capable of controlling the orientation direction of the liquid crystalline compound as described above, but may be a single region.

[0245] The form of the second liquid crystal cell is not particularly limited, and a known method can be used. As the form of the second liquid crystal cell, in addition to the above-mentioned TN-type liquid crystal cell, the methods exemplified in the first liquid crystal cell can also be used.

[0246] Among them, the second liquid crystal cell is preferably selected from the group including a TN-type liquid crystal cell, an IPS-type liquid crystal cell, and a VA-type liquid crystal cell.

[0247] Here, when the second liquid crystal cell is a liquid crystal cell capable of switching the in-plane retardation of the second liquid crystal cell to 0 and λ / 2, in the state where the in-plane retardation of the second liquid crystal cell is λ / 2, the angle formed by the in-plane slow axis direction of the second liquid crystal cell and the absorption axis of the second polarizer is preferably in the range of 45±10°.

[0248] As a liquid crystal cell capable of switching the in-plane retardation to 0 and λ / 2, for example, a VA-type liquid crystal cell can be cited.

[0249] In addition, the in-plane retardation being λ / 2 does not strictly require the in-plane retardation to be λ / 2. The in-plane retardation at a wavelength of 550 nm is preferably 235 to 315 nm, more preferably 255 to 295 nm.

[0250] Hereinafter, in Figure 2 and Figure 3In the manner shown, a modified example in which the second liquid crystal cell 200 is changed from a TN type liquid crystal cell to a VA type liquid crystal cell capable of switching the in-plane phase difference to 0 and λ / 2 will be described. In such a modified example, the light emitted toward Figure 3 the second visual recognition direction 3 can also be switched between blocking and emission according to whether a voltage is applied to the second liquid crystal cell or not.

[0251] Generally, in a VA type liquid crystal cell, in a state where no voltage is applied, the liquid crystalline compound is oriented in the thickness direction of the liquid crystal cell. On the other hand, when a voltage is applied to the liquid crystal cell, the liquid crystalline compound is oriented in the in-plane direction of the liquid crystal cell, thereby generating an in-plane phase difference.

[0252] In a state where the in-plane phase difference of the second liquid crystal cell in the modified example is λ / 2, if the angle formed by the in-plane slow axis direction of the second liquid crystal cell and the absorption axis of the second polarizer is set within the range of 45 ± 10°, then similar to the state where a voltage is applied to the second liquid crystal cell 200 in the manner shown in Figure 2 and Figure 3 , the linearly polarized light components of the first visual recognition direction 2 and the second visual recognition direction 3 in Figure 2 and Figure 3 are respectively converted into polarized light in orthogonal directions. On the other hand, in a state where the in-plane phase difference of the second liquid crystal cell in the modified example is 0, similar to the state where no voltage is applied to the second liquid crystal cell 200 in the manner shown in Figure 2 and Figure 3 , the polarization state of the polarized light component transmitted through the liquid crystal cell can be maintained.

[0253] Therefore, even when a VA type liquid crystal cell is used in the second liquid crystal cell, similar to the manner shown in the above Figure 2 and Figure 3 , the light emitted toward Figure 3 the second visual recognition direction 3 can also be switched between blocking and emission according to whether a voltage is applied to the second liquid crystal cell or not.

[0254] Moreover, the second liquid crystal cell may be a liquid crystal cell in which the in-plane phase difference of the second liquid crystal cell is λ / 2 and the direction of the in-plane slow axis can be changed in the in-plane direction. As such a liquid crystal cell, for example, an IPS type liquid crystal cell can be cited.

[0255] Hereinafter, in Figure 2 and Figure 3In the manner shown, a modified example in which the second liquid crystal cell 200 is changed from a TN type liquid crystal cell to an IPS type liquid crystal cell having an in-plane retardation of λ / 2 and capable of changing the direction of the in-plane slow axis in the in-plane direction will be described. In addition, an in-plane retardation of λ / 2 does not strictly require an in-plane retardation of λ / 2. The in-plane retardation at a wavelength of 550 nm is preferably 235 to 315 nm, more preferably 255 to 295 nm.

[0256] In such a modified example, the light emitted toward Figure 3 the second visual recognition direction 3 can also be switched between blocking and emission according to whether a voltage is applied to the second liquid crystal cell and the degree thereof.

[0257] Generally, in an IPS type liquid crystal cell, the alignment direction of the liquid crystalline compound is controlled according to whether a voltage is applied and the degree thereof. If the alignment direction of the liquid crystalline compound is controlled, the direction of the in-plane slow axis in the liquid crystal cell changes.

[0258] If the in-plane retardation of the second liquid crystal cell in the modified example is λ / 2 and the angle formed by the in-plane slow axis of the second liquid crystal cell and the absorption axis of the second polarizer is set within the range of 45 ± 10°, then, in the same state as when a voltage is applied to the second liquid crystal cell 200 in the manner shown in Figure 2 and Figure 3 , the linearly polarized light components of the first visual recognition direction 2 and the second visual recognition direction 3 in Figure 2 and Figure 3 are respectively converted into polarized light in orthogonal directions. On the other hand, if the angle formed by the in-plane slow axis of the second liquid crystal cell in the modified example and the absorption axis of the second polarizer is set within the range of 0 ± 10°, then substantially no polarization conversion of the linearly polarized light components of the first visual recognition direction 2 and the second visual recognition direction 3 in Figure 2 and Figure 3 is performed, and the polarization state can be maintained.

[0259] Therefore, even when an IPS type liquid crystal cell is used in the second liquid crystal cell, in the same manner as in the above Figure 2 and Figure 3 shown manner, the light emitted toward Figure 3 the second visual recognition direction 3 can also be switched between blocking and emission according to whether a voltage is applied to the second liquid crystal cell.

[0260] [Second light absorption anisotropic layer]

[0261] The second light absorption anisotropic layer in the laminate of the present invention contains a dichroic substance, and the angle γ2 formed by the center axis of transmittance of the second light absorption anisotropic layer and the normal direction of the surface of the second light absorption anisotropic layer is 0 to 45°. In addition, the center axis of transmittance generally coincides with the alignment direction of the dichroic substance.

[0262] As described above, the angle γ2 can be adjusted according to the direction in which the image is desired to be visually recognized. For example, when an anti-peeping function is imparted to the liquid crystal display device, it is preferable to maximize the transmittance in the front direction. In this case, the angle γ2 is preferably 0 to 10°.

[0263] Moreover, the center axis of transmittance of the light absorption anisotropic layer can be set to different directions according to the position within the plane of the first light absorption anisotropic layer. For example, in an in-vehicle display with a curved display surface, in order to prevent the emitted light from any position from being incident on the windshield or the like and to enable the driver to appropriately visually recognize the display image, it is preferable to align the direction of the center axis of transmittance of the second light absorption anisotropic layer with the curved surface for adjustment.

[0264] The method for measuring the angle θ2 is the same as the method for measuring the angle θ1 described above.

[0265] Examples and preferred embodiments of the dichroic pigment and liquid crystalline compound contained in the second light absorption anisotropic layer are the same as those of the first light absorption anisotropic layer, and thus the description is omitted.

[0266] Moreover, the second light absorption anisotropic layer may include layers other than the layer containing the dichroic substance, and these layers are the same as the layers that the first light absorption anisotropic layer may include, and thus the description is omitted.

[0267] [Other Layers]

[0268] The laminate of the present invention may include layers (other layers) other than the above structure.

[0269] Examples of other layers include an optical compensation film, a protective film, an adhesive layer, a bonding layer, a diffusion sheet, a prism sheet, and a reflective sheet. The other layers can be each applied with a known layer.

[0270] Among them, the laminate of the present invention preferably includes an optical compensation film. Examples of the optical compensation film include a retardation layer, and more specifically, an A plate, a B plate, and a C plate. The optical compensation film can be appropriately selected according to the characteristics of the first light absorption anisotropic layer, the second light absorption anisotropic layer, the first liquid crystal cell, and the second liquid crystal cell.

[0271] There are two types of A plates: a positive A plate (positive A plate, +A plate) and a negative A plate (negative A plate, -A plate). When the refractive index in the slow axis direction in the film plane is nx, the refractive index in the direction orthogonal to the slow axis in the plane is ny, and the refractive index in the thickness direction is nz, the positive A plate satisfies the relationship of formula (A1), and the negative A plate satisfies the relationship of formula (A2). In addition, the Rth of the positive A plate shows a positive value, and the Rth of the negative A plate shows a negative value. In addition, the slow axis direction in the film plane is the direction in which the refractive index in the plane is the largest.

[0272] Formula (A1) nx>ny≈nz

[0273] Formula (A2) ny<nx≈nz

[0274] In addition, the above “≈” includes not only the case where the two are exactly the same, but also the case where the two are substantially the same. “Substantially the same” means, for example, that the case where (ny - nz)×d is -10 to 10 nm, preferably -5 to 5 nm, is included in “ny≈nz”, and the case where (nx - nz)×d is -10 to 10 nm, preferably -5 to 5 nm, is included in “nx≈nz”. In addition, in (ny - nz)×d, d is the thickness of the film.

[0275] The B plate is a plate with different values of nx, ny, and nz, and there are two types: a B plate with a negative Rth that satisfies the relationship of formula (B1) and a B plate with a positive Rth that satisfies the relationship of formula (B2).

[0276] Formula (B1) (nx + ny) / 2>nz

[0277] Formula (B2) (nx + ny) / 2<nz

[0278] In addition, the Nz coefficient of the B plate is preferably 1.5 or more, more preferably 2.0 to 10.0, and further preferably 3.0 to 5.0. In addition, the Nz coefficient refers to the value represented by Nz = (nx - nz) / (nx - ny).

[0279] There are two types of C plates: a positive C plate (positive C plate, +C plate) and a negative C plate (negative C plate, -C plate). The positive C plate satisfies the relationship of formula (C1), and the negative C plate satisfies the relationship of formula (C2). In addition, the Rth of the positive C plate shows a negative value, and the Rth of the negative C plate shows a positive value.

[0280] Formula (C1) nz>nx≈ny

[0281] Formula (C2) nz<nx≈ny

[0282] In addition, the above "≈" includes not only the case where the two are exactly the same, but also the case where the two are substantially the same. "Substantially the same" means, for example, that the case where (nx - ny) × d is 0 to 10 nm, preferably 0 to 5 nm, is also included in "nx ≈ ny". In addition, in (ny - nz) × d, d is the thickness of the thin film.

[0283] As the optical compensation film, a B plate is preferably used. Among them, the B plate is preferably disposed between the first light absorption anisotropic layer and the first polarizer, and more preferably disposed such that the angle formed by the absorption axis of the first polarizer and the in-plane slow axis of the B plate is 0 ± 10°.

[0284] <Liquid crystal display device>

[0285] The liquid crystal display device of the present invention includes the laminate of the present invention.

[0286] As the liquid crystal display device, there is no particular limitation, and for example, a liquid crystal display device can be cited. The liquid crystal display device can be used, for example, as a liquid crystal display, a head-up display, a head-mounted display, etc.

[0287] The liquid crystal display device of the present invention can be used in combination with structures commonly used in the art. For example, the liquid crystal display device of the present invention can be combined with a protective film, an optical compensation film, etc.

[0288] As Figure 1 and Figure 2 shown, the liquid crystal display device of the present invention has a laminate 10 and a surface light source 400. The surface light source 400 can be applied to the backlight commonly used in liquid crystal display devices. As the light source of the backlight, for example, a cold cathode lamp, a light-emitting diode (LED), etc. can be used. And, as the surface light source 400, external light can be used.

[0289] As described above, in the liquid crystal display device of the present invention, the light emitted toward Figure 1 the front visual recognition direction 1 of Figure 2 is emitted from the liquid crystal display device, and the light emitted toward the second visual recognition direction 2 is blocked regardless of whether a voltage is applied to the second liquid crystal cell 200. And, the light emitted toward

[0290] the second visual recognition direction 3 of

[0291] <In-vehicle display>

[0292] The in-vehicle display of the present invention includes the above liquid crystal display device of the present invention.

[0293] When the liquid crystal display device of the present invention is applied to an in-vehicle display, light emitted in the front visual recognition direction 1 is emitted from the liquid crystal display device, and for example, can be visually recognized by a passenger different from the driver. Light emitted in the first visual recognition direction 2 is always blocked, so that the image displayed on the windshield or the like does not enter. And, light emitted in the second visual recognition direction 3 of Figure 1 can be switched between blocking and emitting, so that the viewing angle in the left and right directions of the in-vehicle display can be controlled. The in-vehicle display of the present invention can, for example, switch whether the displayed image can be visually recognized in a direction different from the direction of the above-mentioned passenger (for example, the driver's direction). It is also preferable to control the above switching according to the driving state of the vehicle. Figure 2

[0294] Example

[0295] Hereinafter, the present invention will be further described in detail according to the examples.

[0296] The materials, usage amounts, ratios, processing contents, processing steps, etc. shown in the following examples can be appropriately changed as long as they do not depart from the gist of the present invention. Therefore, the scope of the present invention should not be construed in a limiting manner by the examples shown below.

[0297] <Example 1>

[0298] A laminate was obtained through the following steps, and the liquid crystal display device used in Example 1 was fabricated.

[0299] [Fabrication of Optical Film 1]

[0300] An optical film having a light absorption anisotropic layer was fabricated through the following steps.

[0301] (Formation of Alignment Film Layer)

[0302] The following alignment film forming composition 1 was coated on the surface of a commercially available cellulose acylate film (manufactured by FUJIFILM Corporation, trade name FUJITAC TG60UL) using a wire bar. The support on which the coating film was formed was dried with warm air at 140 °C for 120 seconds to form an alignment film AL1, thereby obtaining a cellulose acylate film 1 with an alignment film. The film thickness of the alignment film AL1 was 1 μm.

[0303]

[0304] Polymer PA-1 (wherein the values described in each repeating unit represent the content (mass %) of each repeat relative to all repeating units.)

[0305] [Chemical Formula 1]​

[0306]

[0307] Acid generator PAG-1

[0308] [Chemical formula 2]

[0309]

[0310] Stabilizer DIPEA

[0311] [Chemical formula 3]

[0312]

[0313] (Formation of the photoabsorption anisotropic layer V1)

[0314] Using a wire bar, the following photoabsorption anisotropic layer-forming composition P1 was continuously coated on the obtained cellulose acylate film 1 with an alignment film, and after heating at 120 °C for 60 seconds, it was cooled to room temperature (23 °C).

[0315] Next, it was heated at 85 °C for 60 seconds and then cooled to room temperature again.

[0316] Then, using an LED lamp (center wavelength 365 nm), it was irradiated from the film normal direction for 2 seconds under irradiation conditions of an illuminance of 200 mW / cm 2 , thereby producing a photoabsorption anisotropic layer V1 on the alignment film AL1. The film thickness of the photoabsorption anisotropic layer V1 is 4.5 μm.

[0317]

[0318] Dichroic substance D-1

[0319] [Chemical formula 4]

[0320]

[0321] Dichroic substance D-2

[0322] [Chemical formula 5]

[0323]

[0324] Dichroic substance D-3

[0325] [Chemical formula 6]

[0326]

[0327] Polymeric liquid crystalline compound P-1

[0328] [Chemical formula 7]

[0329]

[0330] Liquid crystalline compound L-1 [a mixture of the following liquid crystalline compounds (RA), (RB), and (RC) at a mass ratio of 84:14:2]

[0331] [Chemical formula 8]

[0332]

[0333] Alignment agent E-1

[0334] [Chemical formula 9]

[0335]

[0336] Alignment agent E-2

[0337] [Chemical formula 10]

[0338]

[0339] Surfactant F-2

[0340] [Chemical formula 11]

[0341]

[0342] (Formation of protective layer B1)

[0343] A coating film was formed by continuously coating the following protective layer-forming composition B1 on the obtained light absorption anisotropic layer V1 using a wire bar.

[0344] Next, the support having the coating film formed thereon was dried with warm air at 60°C for 60 seconds, and then further dried with warm air at 100°C for 120 seconds to form a protective layer B1, thereby producing an optical film 1. The film thickness of the protective layer was 0.5 μm.

[0345] In the produced optical film 1, as a result of measuring the angle of the transmission axis center by the above method, the angle formed by the transmission axis center of the optical film 1 and the normal direction of the surface of the optical film 1 was 0°.

[0346] In addition, none of the layer structures other than the light absorption anisotropic layer V1 of the optical film 1 have light absorption anisotropy. Therefore, the angle of the transmission axis center calculated above can be replaced with the value of the light absorption anisotropic layer V1.

[0347] The transmittance of the optical film 1 at a wavelength of 550 nm was measured using AxoScan OPMF-1 (manufactured by Opto Science, Inc.) The transmittance in the normal direction of the optical film 1 was 78%, and the transmittance in a direction inclined 30° from the normal direction of the optical film 1 was 17%.

[0348]

[0349]

[0350] Pigment compound G-1

[0351] [Chemical formula 12]

[0352]

[0353] [Fabrication of TN-type liquid crystal cell]

[0354] A horizontally aligned polyimide alignment film was applied to two glass substrates with ITO electrodes and dried at high temperature to form an alignment film, which was then subjected to a rubbing treatment.

[0355] Next, a heat-curing sealant was applied to one of the two glass substrates, and a bead spacer (5 μm in diameter) was applied to the other. The two glass substrates were then bonded together, with the surfaces with the alignment films facing each other and the rubbing directions of the alignment films perpendicular to each other. Following bonding, the two glass substrates were vacuum-packed and heated to form an empty liquid crystal cell.

[0356] Liquid crystal (MLC-9100 manufactured by Merck) with positive dielectric anisotropy, birefringence Δn = 0.0854 (wavelength 589 nm, 20°C), and Δε = approximately +8.5 was injected into the empty cell using a vacuum liquid crystal injector. After the liquid crystal was injected, a sealing process was performed to produce a TN-type liquid crystal cell with Δnd = 430 nm.

[0357] In the TN-type liquid crystal cell fabricated above, the rubbed alignment film is in contact with the injected liquid crystal. Therefore, when no voltage is applied between the ITO electrodes, the liquid crystal layer is twisted and aligned at a 90° twist angle between the upper and lower glass substrates. On the other hand, when a voltage is applied between the ITO electrodes, the liquid crystal is aligned vertically.

[0358] [Fabrication of Liquid Crystal Display Device 1]

[0359] A dynabook (registered trademark) laptop computer (manufactured by TOSHIBAC Corporation) equipped with a liquid crystal display was disassembled and the liquid crystal panel removed. Using this liquid crystal panel, optical film 1, a TN liquid crystal cell, and a backlight with Lambertian light distribution, a liquid crystal display device 1 was fabricated to have the structure shown in Table 1. The components were bonded together using SK2057 adhesive.

[0360] The liquid crystal display device 1 used in Example 1 was produced by laminating an optical film 1, a liquid crystal panel, a TN-type liquid crystal cell, the optical film 1, and a backlight in this order from the viewing side. The laminate formed by laminating the optical film 1, the liquid crystal panel, the TN-type liquid crystal cell, and the optical film 1 corresponds to the laminate of the present invention. Here, the optical films 1 were laminated so that the cellulose acylate film faced the viewing side.

[0361] In the liquid crystal panel, the liquid crystal cell (IPS type) is disposed between two polarizers, and the absorption axes of the two polarizers are orthogonal to each other.

[0362] <Examples 1 to 5 and Comparative Examples 1 to 6>

[0363] Liquid crystal display devices 2 to 11 were produced in the same manner as in Example 1 so as to have the structures described in Table 1. Furthermore, components not used in Example 1 were prepared by the following method.

[0364] [Fabrication of VATN Type Liquid Crystal Cell]

[0365] First, a vertically aligned polyimide film was applied to two glass substrates with ITO electrodes and dried at high temperature to form an alignment film.

[0366] Next, a heat-curing sealant was applied to one of the two glass substrates, and a bead spacer (5 μm in diameter) was applied to the other. The two glass substrates were then bonded together, with the surfaces with the alignment films facing each other and the rubbing directions of the alignment films perpendicular to each other. Following bonding, the two glass substrates were vacuum-packed and heated to form an empty liquid crystal cell.

[0367] Using a vacuum liquid crystal injector, liquid crystal (MLC-6886 manufactured by Merck) with negative dielectric anisotropy, refractive index anisotropy Δn = 0.0899 (value at wavelength 589nm, 20°C), and Δε = about -3.6 was injected into the above-mentioned empty unit, and a VATN type liquid crystal unit with Δnd = 450nm was produced through sealing treatment.

[0368] In the VATN liquid crystal cell fabricated above, because the vertical alignment films are in contact with the injected liquid crystal, the liquid crystal layer is vertically aligned between the upper and lower glass substrates when no voltage is applied between the ITO electrodes. However, when a voltage is applied between the ITO electrodes, the liquid crystal molecules exhibit negative dielectric anisotropy, exerting a force that tilts the liquid crystal molecules parallel to the glass substrates. This forces the liquid crystal molecules along the rubbing direction of the upper and lower alignment films, resulting in a twisted alignment at a 90° angle between the upper and lower glass substrates.

[0369] [Fabrication of IPS-type liquid crystal cell]

[0370] An IPS liquid crystal cell was produced according to Example 2 of Japanese Patent Application Laid-Open No. 2005-351924. An IPS liquid crystal cell 1 having an in-plane retardation of λ / 2 and an IPS liquid crystal cell 2 having an in-plane retardation of λ / 4 were produced.

[0371] When an IPS-type liquid crystal unit is assembled into a liquid crystal display device, it is configured so that the orientation direction of the liquid crystal in the IPS unit is parallel to the absorption axis of the polarizer (second polarizer) attached to the backlight side of the liquid crystal panel when no voltage is applied, and is set to be 45° relative to the absorption axis of the second polarizer when voltage is applied.

[0372] [Fabrication of PDLC Cell]

[0373] According to Example 1 of International Publication No. 2021 / 200828, a PDLC (Polymer Dispersed Liquid Crystal) cell was produced.

[0374] [Organic EL panel]

[0375] An iPhone (registered trademark) 12 manufactured by Apple Inc. and equipped with an organic EL panel (organic EL display device) was disassembled, and the organic EL panel was removed.

[0376] [Blind film]

[0377] A privacy filter (PF12.1W9H2) manufactured by 3M Company was used.

[0378] [Fabrication of λ / 4 Plate]

[0379] (Preparation of Photo-Alignment Film-Forming Composition)

[0380] -Synthesis of polymer E-2-

[0381] Into a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel and a reflux cooling tube, 100.0 parts by mass of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 500 parts by mass of methyl isobutyl ketone and 10.0 parts by mass of triethylamine were charged, and the mixture was stirred at room temperature. Subsequently, 100 parts by mass of deionized water was added dropwise from the dropping funnel to the obtained mixture over 30 minutes, and the mixture was reacted at 80°C for 6 hours while mixing under reflux. After the reaction was completed, the organic phase was taken out and washed with a 0.2% by mass aqueous solution of ammonium nitrate until the washed water became neutral. Then, the solvent and water were distilled off from the obtained organic phase under reduced pressure to obtain a polyorganosiloxane having an epoxy group in the form of a viscous transparent liquid.

[0382] The polyorganosiloxane having epoxy groups was subjected to 1 H-NMR (Nuclear Magnetic Resonance) analysis revealed a peak at a chemical shift (Δ) of 3.2 ppm, indicating theoretical intensity for an oxirane group, confirming no side reactions with epoxy groups during the reaction. The weight-average molecular weight (Mw) of this epoxy-containing polyorganosiloxane was 2200, and its epoxy equivalent was 186 g / mol.

[0383] Next, a 100 ml three-necked flask was charged with 10.1 parts by mass of the polyorganosiloxane having an epoxy group obtained above, 0.5 parts by mass of a carboxylic acid containing an acrylic acid group (manufactured by TOAGOSEI CO., LTD., trade name "ARONIX M-5300", acrylic acid ω-carboxyl polycaprolactone (polymerization degree n≈2)), 20 parts by mass of butyl acetate, 1.5 parts by mass of a cinnamic acid derivative obtained by the method of Synthesis Example 1 of JP-A-2015-26050, and 0.3 parts by mass of tetrabutylammonium bromide, and the obtained mixture was stirred at 90 ° C for 12 hours. After stirring, the mixture was diluted with butyl acetate in an amount (mass) equal to that of the obtained mixture, and the diluted mixture was washed with water three times. The operation of concentrating the obtained mixture and diluting it with butyl acetate was repeated twice, and finally a solution containing a polyorganosiloxane having a photo-alignment group (polymer E-2 below) was obtained. The weight average molecular weight Mw of the polymer E-2 was 9000. 1 As a result of H-NMR analysis, the content of components having cinnamate groups in polymer E-2 was 23.7% by mass.

[0384] [Chemical Formula 13]

[0385]

[0386] -Preparation of a composition for forming a photo-alignment film-

[0387] The following components were mixed to prepare a composition for forming a photo-alignment film.

[0388]

[0389]

[0390] [Chemical formula 14]

[0391]

[0392] Additive (B-1): TA-60B manufactured by San-Apro Ltd. (hereinafter, refer to the structural formula)

[0393] [Chemical formula 15]

[0394]

[0395] (Preparation of Coating Liquid for Optically Anisotropic Layer)

[0396] An optically anisotropic layer coating liquid having the following composition was prepared.

[0397]

[0398]

[0399] In addition, the group adjacent to the acryloyloxy group of the following liquid crystal compounds L-3 and L-4 represents an acryloyl group (a group in which a methyl group is substituted with a vinyl group), and the following liquid crystal compounds L-3 and L-4 represent a mixture of positional isomers having different positions of the methyl group.

[0400] The numerical values in the repeating units in the leveling agent G-1 represent the mole % of each repeating unit relative to all repeating units in the leveling agent G-1.

[0401] [Chemical Formula 16]

[0402]

[0403]

[0404] (Production of Cellulose Acylate Film 1)

[0405] - Preparation of core layer cellulose acylate concentrate

[0406] The following composition was placed in a mixing tank and stirred to dissolve the components, thereby preparing a cellulose acetate solution to be used as a core layer cellulose acylate dope.

[0407]

[0408] Compound F

[0409] [Chemical formula 17]

[0410]

[0411] - Preparation of the outer layer cellulose acylate concentrated solution

[0412] A cellulose acetate solution used as the outer layer cellulose acylate concentrated solution was prepared by adding 10 parts by mass of the following matting agent solution to 90 parts by mass of the above-mentioned core layer cellulose acylate concentrated solution.

[0413]

[0414]

[0415] (Preparation of the cellulose acylate film 1)

[0416] After filtering the above-mentioned core layer cellulose acylate concentrated solution and the above-mentioned outer layer cellulose acylate concentrated solution with a filter paper having an average pore size of 34 mm and a sintered metal filter having an average pore size of 10 mm, the above-mentioned core layer cellulose acylate concentrated solution and the outer layer cellulose acylate concentrated solutions on both sides thereof were simultaneously cast from a casting die onto a 20 °C drum (a belt casting machine) in three layers.

[0417] Next, at the time when the solvent content rate of the film on the drum was approximately 20% by mass, the film was peeled off from the drum, and both ends in the width direction of the film were fixed with a tenter clamp, and dried while being stretched transversely at a stretching ratio of 1.1 times.

[0418] Then, the obtained film was further dried by conveying it between the rollers of a heat treatment device to produce an optical film having a thickness of 40 mm, which was used as the cellulose acylate film 1. The in-plane retardation of the obtained cellulose acylate film 1 was 0 nm.

[0419] A composition for forming a photo-alignment film prepared in advance was coated on one side of the produced cellulose acylate film 1 with a bar coater.

[0420] After coating, it was dried on a hot plate at 120 °C for 1 minute to remove the solvent, and a composition layer for forming a photo-alignment film having a thickness of 0.3 mm was formed.

[0421] A photo-alignment film was formed by irradiating the obtained composition layer for forming a photo-alignment film with polarized ultraviolet light (10 mJ / cm 2 , using an ultra-high pressure mercury lamp).

[0422] Next, a coating liquid for an optically anisotropic layer prepared in advance was coated on the photo-alignment film with a bar coater to form a composition layer.

[0423] The formed composition layer was once heated to 110° C. on a hot plate and then cooled to 60° C. to stabilize the orientation.

[0424] Then, the temperature was maintained at 60°C and the samples were irradiated with ultraviolet light (500 mJ / cm 2 The orientation was fixed using an ultra-high pressure mercury lamp to form an optically anisotropic layer with a thickness of 2.3 mm, thereby producing a λ / 4 plate 1 (λ / 4 phase difference film 1). The obtained λ / 4 plate 1 had an in-plane retardation of 140 nm at a wavelength of 550 nm.

[0425] [Production of B plate]

[0426] (Extrusion molding)

[0427] Cyclic olefin resin ARTON G7810 (JSR Corporation) was dried at 100°C for more than 2 hours and melt-extruded using a twin-screw kneading extruder at 280°C. A mesh filter, a gear pump, and a leaf disk filter were sequentially placed between the extruder and the die, and these were connected by melt piping. The film was extruded from a T-die with a width of 1000 mm and a lip gap of 1 mm, and then cast onto three casting rolls set at 180°C, 175°C, and 170°C, to obtain an unstretched film 1 with a width of 900 mm and a thickness of 320 μm.

[0428] (Stretching / heat setting)

[0429] The unstretched film 1 was subjected to a stretching step and a heat-setting step during transport by the following method.

[0430] (a) Longitudinal stretching

[0431] The unstretched film 1 was longitudinally stretched under the following conditions while being conveyed using an inter-roll longitudinal stretching machine having an aspect ratio (L / W) of 0.2.

[0432] <Condition>

[0433] Preheating temperature: 170℃

[0434] Stretching temperature: 170℃

[0435] Stretch ratio: 155%

[0436] (b) Transverse stretching

[0437] The longitudinally stretched film was then stretched in the transverse direction under the following conditions while being conveyed using a tenter.

[0438] <Condition>

[0439] Preheating temperature: 170 °C

[0440] Drawing temperature: 170 °C

[0441] Drawing ratio: 80%

[0442] (c) Heat setting

[0443] After the drawing process, the drawn film was then held at its ends by a tenter frame jig, and while maintaining the two ends of the drawn film in a constant width (expansion or contraction range within 3%), heat treatment was carried out under the following conditions to perform heat setting.

[0444] Heat setting temperature: 165 °C

[0445] Heat setting time: 30 seconds

[0446] In addition, the preheating temperature, drawing temperature, and heat setting temperature are the average values of the values measured at 5 points in the width direction using a radiation thermometer.

[0447] (Winding)

[0448] After heat setting, both ends were cut, and winding was carried out at a tension of 25 kg / m to obtain a film roll with a width of 1340 mm and a roll length of 2000 m.

[0449] The obtained drawn film had a Re of 120 nm, an Rth of 420 nm, an Nz coefficient of 4.0, the slow axis was in the MD direction, and the film thickness was 80 μm. This was designated as B plate 1. When manufacturing a liquid crystal display device, it was arranged such that the slow axis of B plate was parallel to the absorption axis of the polarizer on the visually recognizable side of the liquid crystal panel.

[0450] In addition, as described above, B plate refers to a biaxial optical component in which the refractive indices nx, ny, and nz have different values, and the Nz coefficient refers to the value represented by Nz = (nx - nz) / (nx - ny).

[0451] (Examples 6 to 9)

[0452] As recorded in Table 1, optical film 1 was respectively set as optical films 2 to 5, and in other respects, liquid crystal display devices 12 to 15 were manufactured in the same manner as in Example 1.

[0453] [Manufacture of optical film 2]

[0454] A light absorption anisotropic layer forming composition P2 having the following composition was used instead of the light absorption anisotropic layer forming composition P1, and in other respects, an optical film 2 having a light absorption anisotropic layer V2 was manufactured by the same method as for optical film 1.

[0455] In the produced optical film 2, as a result of measuring the angle of the transmittance central axis by the above method, the angle formed by the transmittance central axis of the optical film 2 and the normal direction of the surface of the optical film 2 is 0°.

[0456] In addition, among the layer structures of the optical film 2 other than the light absorption anisotropic layer V2, none have light absorption anisotropy. Therefore, the angle of the transmittance central axis calculated above can be replaced with the value of the light absorption anisotropic layer V2.

[0457] Moreover, the transmittance of the optical film 2 at a wavelength of 550 nm was measured using AxoScan OPMF-1 (manufactured by Opto Science, Inc.). The transmittance in the normal direction of the optical film 2 is 69%, and the transmittance in the direction inclined 30° from the normal direction of the optical film 2 is 15%.

[0458]

[0459]

[0460] Dichroic substance D-4

[0461] [Chemical formula 18]

[0462]

[0463] Dichroic substance D-5

[0464] [Chemical formula 19]

[0465]

[0466] Dichroic substance D-6

[0467] [Chemical formula 20]

[0468]

[0469] [Production of optical film 3]

[0470] An optical film 3 having a light absorption anisotropic layer V3 was produced by the same method as that of the optical film 1, except that the composition P3 for forming a light absorption anisotropic layer having the following composition was used instead of the composition P1 for forming a light absorption anisotropic layer.

[0471] In the produced optical film 3, as a result of measuring the angle of the transmittance central axis by the above method, the angle formed by the transmittance central axis of the optical film 3 and the normal direction of the surface of the optical film 3 is 0°.

[0472] Note that, since the layer structure of the optical film 3 other than the light absorption anisotropic layer V3 does not have light absorption anisotropy, the angle of the transmittance central axis calculated above can be replaced by the value of the light absorption anisotropic layer V3 of the optical film 3 .

[0473] The transmittance of the optical film at a wavelength of 550 nm was measured using AxoScan OPMF-1 (manufactured by Opto Science, Inc.) The transmittance in the normal direction of the optical film 3 was 70%, and the transmittance in a direction inclined 30° from the normal direction of the optical film 3 was 15%.

[0474]

[0475] Liquid crystal compound L-5

[0476] [Chemical Formula 21]

[0477]

[0478] Liquid crystal compound L-6

[0479] [Chemical Formula 22]

[0480]

[0481] [Production of Optical Film 4]

[0482] An optical film 4 having an optically anisotropic layer V4 was produced by the same method as that for the optical film 1 except that a composition P4 for forming a light-absorbing anisotropic layer having the following composition was used instead of the composition P1 for forming a light-absorbing anisotropic layer.

[0483] In the produced optical film 4 , the angle of the transmittance central axis was measured by the above method. As a result, the angle formed between the transmittance central axis of the optical film 4 and the normal direction of the surface of the optical film 4 was 0°.

[0484] Note that, since the optical film 4 has no layer structure other than the light absorption anisotropic layer V4 and thus the angle of the transmittance central axis calculated above can be replaced by the value of the light absorption anisotropic layer V4 of the optical film 4 .

[0485] The transmittance of the optical film at a wavelength of 550 nm was measured using AxoScan OPMF-1 (manufactured by Opto Science, Inc.) The transmittance in the normal direction of the optical film 4 was 65%, and the transmittance in a direction inclined 30° from the normal direction of the optical film 4 was 12%.

[0486]

[0487] [Production of Optical Film 5]

[0488] An optical film 5 having a light absorption anisotropic layer V5 was produced by the same method as that for the optical film 1 except that a light absorption anisotropic layer-forming composition P5 having the following composition was used instead of the light absorption anisotropic layer-forming composition P1.

[0489] In the produced optical film 5 , the angle of the transmittance central axis was measured by the above-mentioned method. As a result, the angle formed between the transmittance central axis of the optical film 5 and the normal direction of the surface of the optical film 5 was 0°.

[0490] Note that, since the optical film 5 has no layer structure other than the light absorption anisotropic layer V5 and thus the angle of the transmittance central axis calculated above can be replaced by the value of the light absorption anisotropic layer V5 , none of the layer structures has light absorption anisotropy.

[0491] The transmittance of the optical film 5 at a wavelength of 550 nm was measured using AxoScan OPMF-1 (manufactured by Opto Science, Inc.) The transmittance in the normal direction of the optical film 5 was 74%, and the transmittance in a direction inclined 30° from the normal direction of the optical film 5 was 16%.

[0492]

[0493] <Evaluation>

[0494] [Evaluation of the horizontal viewing angle controllability and vertical light shielding properties of a liquid crystal display device]

[0495] In each manufactured LCD device, the voltage applied to the liquid crystal cell or PDLC cell was controlled to evaluate whether the device could switch between blocking and transmitting light emitted in the left and right directions. In other words, the device was evaluated for its ability to control the viewing angle in the left and right directions.

[0496] Furthermore, it was evaluated whether light emitted in the up-down direction, which is a direction perpendicular to the left-right direction, was blocked regardless of voltage control.

[0497] Here, the horizontal direction refers to the direction parallel to the absorption axis of the polarizer on the viewing side of the liquid crystal panel, which is set to the direction from an azimuth angle of 0° to 180°. Furthermore, the vertical direction refers to the direction perpendicular to the absorption axis of the polarizer on the viewing side of the liquid crystal panel, which is set to the direction from an azimuth angle of 90° to 270°.

[0498] For example, "shielded to the left" means that the ratio of the brightness at an azimuth angle of 0° and a polar angle of 30° to the brightness at a polar angle of 0° (a direction perpendicular to the surface of the liquid crystal display device) is 0.5 or less. "Shielded to the right, upward, and downward" means that the ratio of the brightness at a polar angle of 30° to the brightness at a polar angle of 0° is 0.5 or less.

[0499] The brightness is measured in the same manner as in the "Evaluation of light-shielding properties in an oblique direction when viewing angle is controlled" described later.

[0500] [Evaluation of light-shielding properties in the oblique direction when viewing angle is controlled]

[0501] Using the manufactured liquid crystal display device and an "EZ-Contrast XL88" measuring instrument (manufactured by ELDIM), luminance was measured in 15° increments from an azimuth angle of 0° to 360° counterclockwise, and in 5° increments from a polar angle of 0° (frontal direction) to 80°. While controlling the horizontal viewing angle, the ratios of luminance in the horizontal direction (azimuth angle 0°, polar angle 30°, and azimuth angle 180°, polar angle 30°) to luminance in the frontal direction (polar angle 0°) and the ratios of luminance in the vertical direction (azimuth angle 90°, polar angle 30°, and azimuth angle 270°, polar angle 30°) to luminance in the frontal direction (polar angle 0°) were calculated. Light-shielding properties in oblique directions with controlled viewing angles were evaluated using the following criteria.

[0502] Practically, the light-shielding property evaluation in the oblique direction when the viewing angle is controlled is preferably B or A.

[0503] The horizontal brightness is the average of the brightness at an azimuth angle of 0° and a polar angle of 30°, and the brightness at an azimuth angle of 180° and a polar angle of 30°. The vertical brightness is the average of the brightness at an azimuth angle of 90° and a polar angle of 30°, and the brightness at an azimuth angle of 270° and a polar angle of 30°.

[0504] A: 0.2 or less in both up and down directions and left and right directions

[0505] B: 0.3 or less in both the up and down directions and the left and right directions, and greater than 0.2 in at least one direction

[0506] C: Greater than 0.3 in either the up-down or left-right direction

[0507] [Light resistance evaluation]

[0508] The produced liquid crystal display device was irradiated with xenon light from the front for 150 hours using a super xenon lamp weathering tester SX75 manufactured by Suga Test Instruments Co., Ltd.

[0509] Before and after irradiation, the brightness in the left-right direction (azimuth angle 0°, polar angle 30° and azimuth angle 180°, polar angle 30°) was measured by the same method as described above, the change in brightness before and after irradiation was calculated, and the light resistance was evaluated based on the following criteria. In addition, the change in brightness (%) was calculated by the following formula.

[0510] (Change in brightness) = 100 × ((Brightness before irradiation) - (Brightness after irradiation)) / (Brightness before irradiation)

[0511] In addition, the brightness in the left-right direction was the average of the brightness at azimuth angle 0°, polar angle 30° and the brightness at azimuth angle 180°, polar angle 30°.

[0512] Practically, the change in brightness is preferably evaluated as Grade B or Grade A.

[0513] A: The change in brightness is less than 2%.

[0514] B: The change in brightness is 2% or more and less than 5%.

[0515] C: The change in brightness is 5% or more.

[0516] <Results>

[0517] The structures of the liquid crystal display devices of each example and each comparative example and the above evaluation results are shown in Table 1 (Parts 1 and 2).

[0518] In addition, in Table 1, in the column of "Viewing angle controllability (left-right direction)", the case where there is viewing angle controllability in the left-right direction is recorded as "A", and the case where there is no viewing angle controllability in the left-right direction is recorded as "B".

[0519] In Table 1, in the column of "Always light-shielding property (up-down direction)", regardless of whether the viewing angle is controlled in the left-right direction, the case where it is always light-shielded in the up-down direction is recorded as "A", and the case where it is not always light-shielded in the up-down direction is recorded as "B".

[0520]

[0521] From the results shown in Table 1, it was confirmed that in the liquid crystal display devices of Examples 1 to 6 having a prescribed structure in a prescribed order, there is viewing angle controllability in the left-right direction and it is always light-shielded in the up-down direction. Also, it was confirmed that the light-shielding property in the tilting direction when the viewing angle is not controlled is excellent and the light resistance is also excellent. And it was confirmed that the desired effects are also exhibited in the liquid crystal display devices of Examples 6 to 9.

[0522] On the other hand, in the liquid crystal display devices of Comparative Examples 1, 2, and 4 to 6 that do not have a specified structure or do not have a specified structure in a specified order, it is impossible to balance the light-shielding property and light resistance in the tilting direction when the viewing angle is not controlled. Further, in the liquid crystal display device of Comparative Example 3 that does not have a specified structure, light cannot be always shielded in the vertical direction.

[0523] Moreover, it was confirmed that the liquid crystal display device of Example 5 using the B plate has more excellent light-shielding property in the tilting direction. Further, in the liquid crystal display device of Example 5, light leakage in the directions of azimuth angles of 45°, 135°, 225°, and 315° is suppressed, and better display performance can be obtained.

[0524] Symbol Explanation

[0525] 1 - Front visual recognition direction, 2 - First visual recognition direction, 3 - Second visual recognition direction, 10 - Laminate, 12a, 12b - Transmittance central axis, 32a, 32b - Absorption axis, 102a - First light absorption anisotropic layer, 102b - Second light absorption anisotropic layer, 200 - Second liquid crystal cell, 300 - Liquid crystal panel, 302 - First liquid crystal cell, 304a - First polarizer, 304b - Second polarizer, 400 - Surface light source, 500 - Liquid crystal display device.

Claims

1. A laminate having, in this order: A first light absorption anisotropic layer; A first polarizer; A first liquid crystal cell; A second polarizer; A second liquid crystal cell; and A second light absorption anisotropic layer, wherein The absorption axis of the first polarizer is orthogonal to the absorption axis of the second polarizer, The first light absorption anisotropic layer and the second light absorption anisotropic layer contain a dichroic material, The angle θ1 formed by the transmittance central axis of the first light absorption anisotropic layer and the normal direction of the surface of the first light absorption anisotropic layer is 0 to 45°, The angle θ2 formed by the transmittance central axis of the second light absorption anisotropic layer and the normal direction of the surface of the second light absorption anisotropic layer is 0 to 45°.

2. The laminate according to claim 1, wherein The dichroic materials in the first light absorption anisotropic layer and the second light absorption anisotropic layer have an arrangement structure of the dichroic materials with respect to each other.

3. The laminate according to claim 1, wherein The first liquid crystal cell and the second liquid crystal cell are each independently selected from the group consisting of a twisted nematic liquid crystal cell, an in-plane switching liquid crystal cell, and a vertical alignment liquid crystal cell.

4. The laminate according to claim 1, wherein The second liquid crystal cell is a liquid crystal cell capable of switching the in-plane phase difference of the second liquid crystal cell to 0 and λ / 2, In a state where the in-plane phase difference of the second liquid crystal cell is λ / 2, the angle formed by the in-plane slow axis direction of the second liquid crystal cell and the absorption axis of the second polarizer is in the range of 45 ± 10°.

5. The laminate according to claim 1, wherein The second liquid crystal cell is a liquid crystal cell having an in-plane phase difference of λ / 2 and capable of controlling the direction of the in-plane slow axis, The second liquid crystal cell can control the in-plane slow axis within a range where the angle formed by the in-plane slow axis direction of the second liquid crystal cell and the absorption axis of the second polarizer is in the range of 45 ± 10° and 0 ± 10°.

6. A liquid crystal display device comprising the laminate according to any one of claims 1 to 5.

7. A vehicle-mounted display comprising the liquid crystal display device according to claim 6.

Images