JP2022145604A - optical laminate - Google Patents

Abstract

To provide an optical laminate with which it is possible to easily reduce the coloration of a black image when a display device is seen from an oblique direction.SOLUTION: The optical laminate includes a pigment-containing layer, a polarization layer and a retardation layer having an in-plane phase difference, in the order stated. The pigment-containing layer includes a dichroic dye having a maximum absorption in the wavelength range of 400 nm to 750 nm, inclusive, and satisfies formulas (1) and (2). Formula (1): 0.001≤AxC≤0.3; formula (2): AxC(z=60)/AxC>2. [In formulas (1) and (2), AxC and AxC(z=60) both represent the absorbance of absorption maximum wavelength in the wavelength range of 400 nm to 750 nm, inclusive, of the pigment-containing layer; AxC represents the absorbance of linearly polarized light vibrating in an axis x direction; and AxC(z=60) represents the absorbance of linearly polarized light vibrating in the axis x direction when the pigment-containing layer is rotated 60° around an axis y.]SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to an optical layered body and further to a display device provided with the same.

2. Description of the Related Art In an organic electroluminescence (hereinafter sometimes referred to as “organic EL”) display device, a panel that displays an image reflects externally incident light due to electrodes and the like incorporated therein. This reflected light makes the image displayed on the panel difficult to see. Therefore, it is widely practiced to arrange a circularly polarizing plate on the viewing side of the panel. A circularly polarizing plate is an optical element in which a linear polarizing plate and a λ/4 retardation plate are laminated, and the absorption axis of the linear polarizing plate and the slow axis of the λ/4 retardation plate form an angle of approximately 45°. ing. The circularly polarizing plate is usually arranged so that the linear polarizing plate is on the viewing side and the λ/4 retardation plate is on the panel side. When an organic EL display device having such a circularly polarizing plate is viewed from the front, the influence of reflected light is reduced, making it possible to display black images with high image quality.

On the other hand, when an organic EL display device having a circularly polarizing plate is viewed from an oblique direction, a black image may appear colored. This is because when the organic EL display device is viewed from an oblique direction, the λ/4 retardation plate functions outside the ideal retardation value. In addition, since metal electrodes are incorporated inside the panel of the organic EL display device, when the organic EL display device is viewed from an oblique direction, the phase difference of the reflected light obliquely reflected on the surface of the metal electrode is to be influenced. Therefore, when the organic EL display device is viewed from an oblique direction, a black image is colored in a different color for each target panel.

A vertically aligned liquid crystal cured film disclosed in Japanese Patent Laid-Open No. 2002-200300 can be cited as a solution that can solve such problems. This vertically aligned liquid crystal cured film is a cured film obtained by curing a composition containing a dichroic dye and a polymerizable liquid crystal compound while the polymerizable liquid crystal compound is vertically aligned. Since this cured film exhibits retardation in the thickness direction, it functions as a so-called positive C retardation plate. By combining this positive C retardation plate and the λ / 4 retardation plate and applying it to an organic EL display device, the retardation value of the λ / 4 retardation plate when viewed from an oblique direction is compensated, and λ / An ideal retardation value of four retarders can be realized.

In an organic EL display device using a vertically aligned liquid crystal cured film, a slight coloration may remain in the black image. The vertically aligned liquid crystal cured film described in Patent Document 1 also has a function as a colored layer due to the vertically aligned dichroic dye in the film. Therefore, by selecting, as the dichroic dye contained in the vertically aligned liquid crystal film, a dichroic dye having a color complementary to the coloring of the black image when the organic EL display device is viewed from an oblique direction, the black image can be obtained. It is also possible to cancel out the slightly remaining coloring.

Japanese Unexamined Patent Application Publication No. 2020-76920

However, in a circularly polarizing plate in which a linear polarizing plate, a λ/4 retardation plate, and a vertically aligned liquid crystal cured film are laminated, it is necessary to simultaneously control the retardation value in the thickness direction of the vertically aligned liquid crystal cured film and the degree of coloring. be. For this control, it is necessary to select a polymerizable liquid crystal compound for producing a vertically aligned liquid crystal cured film, a dichroic dye to be combined with it, and adjust the compounding ratio of these compounds. It is complicated and requires much trial and error.

The present inventor has made extensive studies to easily produce a circularly polarizing plate suitable for the intended panel without much trial and error. As a result, the two functions of the vertically aligned liquid crystal cured film, that is, the function as a positive C retardation plate and the function as a colored layer having a vertically aligned dichroic dye, are performed by independent layers, and the colored layer By arranging a layer that functions as a layer further on the viewing side than the linear polarizing plate, the inventors found that the retardation value in the thickness direction and the degree of coloring of the black image can be controlled independently of each other, resulting in the present invention. .

An object of the present invention is to provide an optical layered body and a display device having the same, which can easily reduce the coloring of a black image when the display device is viewed from an oblique direction.

The present invention provides the following optical laminate and display device.
[1] An optical laminate comprising a dye-containing layer, a polarizing layer, and a retardation layer having an in-plane retardation in this order,
The dye-containing layer is
Containing a dichroic dye having a maximum absorption in the wavelength range of 400 nm or more and 750 nm or less,
An optical laminate that satisfies the relationships of the following formulas (1) and (2).
0.001≤AxC≤0.3 (1)
AxC(z=60)/AxC>2 (2)
[In formulas (1) and (2),
AxC is the absorbance of the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer, and represents the absorbance of linearly polarized light vibrating in the x-axis direction,
AxC (z = 60) is the absorbance at the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer, and the x when the dye-containing layer is rotated by 60° with the y axis as the rotation axis. represents the absorbance of linearly polarized light oscillating in the axial direction,
The x-axis represents an arbitrary direction in the plane of the dye-containing layer, and the y-axis represents a direction perpendicular to the x-axis in the plane of the dye-containing layer. ]
[2] Production of a laminate comprising, in this order, the dye-containing layer, the polarizing layer, the retardation layer, and a vertically aligned liquid crystal layer cured in a state in which the polymerizable liquid crystal compound is aligned in the lamination direction of the optical laminate. The optical laminate according to [1], which is an intermediate.
[3] An optical laminate comprising, in this order, a dye-containing layer, a polarizing layer, a retardation layer having an in-plane retardation, and a vertically aligned liquid crystal layer,
The vertically aligned liquid crystal layer is a cured product layer cured in a state in which the polymerizable liquid crystal compound is oriented in the lamination direction of the optical laminate,
The dye-containing layer is
Containing a dichroic dye having a maximum absorption between wavelengths of 400 nm and 750 nm,
An optical laminate that satisfies the relationships of the following formulas (1) and (2).
0.001≤AxC≤0.3 (1)
AxC(z=60)/AxC>2 (2)
[In formulas (1) and (2),
AxC is the absorbance of the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer, and represents the absorbance of linearly polarized light vibrating in the x-axis direction,
AxC (z = 60) is the absorbance at the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer, and the x when the dye-containing layer is rotated by 60° with the y axis as the rotation axis. represents the absorbance of linearly polarized light oscillating in the axial direction,
The x-axis represents an arbitrary direction in the plane of the dye-containing layer, and the y-axis represents a direction perpendicular to the x-axis in the plane of the dye-containing layer. ]
[4] The optical laminate according to any one of [1] to [3], wherein the dye-containing layer further includes a cured product obtained by curing the polymerizable liquid crystal compound in a lamination direction of the optical laminate. body.
[5] Any one of [1] to [4], wherein the retardation layer is a horizontally aligned liquid crystal layer cured in a state in which the polymerizable liquid crystal compound is aligned in a direction orthogonal to the lamination direction of the optical layered body. An optical laminate as described.
[6] The optical layered body according to any one of [1] to [5], wherein the retardation layer satisfies the relationship of formula (3) below.
ReA(450)/ReA(550)<1.00 (3)
[In formula (3), ReA(450) and ReA(550) represent in-plane retardation values of the retardation layer at wavelengths of 450 nm and 550 nm, respectively. ]
[7] The optical layered body according to any one of [1] to [6], wherein the retardation layer satisfies the relationship of formula (4) below.
120 nm≦ReA(550)≦170 nm (4)
[In formula (4), ReA(550) represents an in-plane retardation value of the retardation layer at a wavelength of 550 nm. ]
[8] The optical laminate according to any one of [1] to [7], wherein the angle formed by the absorption axis of the polarizing layer and the slow axis of the retardation layer is within the range of 45°±5°. body.
[9] The optical laminate according to any one of [1] to [8], wherein the dichroic dye is an azo dye.
[10] The optical laminate according to any one of [1] to [9], wherein the dye-containing layer satisfies any one of [a1] to [a3] below.
[a1] having maximum absorption in both the wavelength range of 400 nm or more and less than 550 nm and the wavelength range of 550 nm or more and less than 700 nm;
[a2] has a maximum absorption in a wavelength range of 400 nm or more and less than 550 nm, and does not have a maximum absorption in a wavelength range of 550 nm or more and 700 nm or less;
[a3] It has no maximum absorption in the wavelength range of 400 nm or more and less than 550 nm, but has maximum absorption in the wavelength range of 550 nm or more and 700 nm or less.
[11] The optical layered body according to any one of [1] to [10], further comprising a hard coat layer on the side of the dye-containing layer opposite to the polarizing layer.
[12] The optical layered body according to any one of [1] to [11], further comprising a protective film on the side of the dye-containing layer opposite to the polarizing layer.
[13] further comprising an adhesive layer between the retardation layer and the vertically aligned liquid crystal layer;
The optical laminate according to any one of [1] to [12], wherein the adhesive layer is in direct contact with the retardation layer and the vertically aligned liquid crystal layer.
[14] The optical laminate according to [13], wherein the adhesive layer is a cured product layer of an ultraviolet curable adhesive composition.
[15] Provided with the optical layered body according to any one of [1] to [14],
In the display device, the optical layered body is arranged such that the dye-containing layer is located on the viewing side of the polarizing layer.
[16] The display device according to [15], which is an organic EL display device.

According to the optical laminate of the present invention, it is possible to easily reduce the coloring of a black image when viewing the display device from an oblique direction.

1 is a cross-sectional view schematically showing an optical layered body according to one embodiment of the present invention; FIG. 1. It is the schematic which shows typically an example of the manufacturing method of the optical laminated body shown in FIG. FIG. 4 is a cross-sectional view schematically showing an optical layered body according to another embodiment of the present invention; FIG. 5 is a cross-sectional view schematically showing an optical layered body according to still another embodiment of the present invention; FIG. 5 is a cross-sectional view schematically showing an optical layered body according to still another embodiment of the present invention;

Preferred embodiments of the optical layered body and the display device will be described below with reference to the drawings. In each drawing, the same reference numerals are assigned to the same members as those previously described, and the description thereof will be omitted.

[Embodiment 1]
(Optical laminate)
FIG. 1 is a cross-sectional view schematically showing an optical layered body according to one embodiment of the present invention. As shown in FIG. 1, the optical layered body 1 includes a dye-containing layer 11, a polarizing layer 12, and a retardation layer 13 having an in-plane retardation in this order. The optical layered body 1 preferably forms an elliptically polarizing plate (including a circularly polarizing plate) with the polarizing layer 12 and the retardation layer 13 . The optical laminate 1 may further have a hard coat layer 16 or a protective film 15 on the opposite side of the dye-containing layer 11 from the polarizing layer 12 side. The optical laminate 1 shown in FIG. 1 has a hard coat layer 16 and a protective film 15 at the same time. When the optical laminate 1 has the hard coat layer 16 and the protective film 15 at the same time, it is preferable to have the protective film 15 and the hard coat layer 16 in this order from the dye-containing layer 11 side.

Each layer constituting the optical layered body 1 is preferably laminated via a bonding layer which is a pressure-sensitive adhesive layer or an adhesive layer. When the optical layered body 1 has the hard coat layer 16 and the protective film 15 at the same time, it is preferable that the protective film 15 and the hard coat layer 16 are provided so as to be in direct contact with each other without a bonding layer interposed therebetween.

When the dye-containing layer 11, the polarizing layer 12, and the retardation layer 13 are layers formed using a liquid crystal compound such as a polymerizable liquid crystal compound, the optical laminate 1 is a layer formed using the liquid crystal compound. It may have an alignment film for regulating the alignment of the liquid crystal compound so that it is in direct contact with the liquid crystal compound. Even if it has a substrate for forming a layer or alignment film formed using the liquid crystal compound good. The layer or alignment film formed using the liquid crystal compound and the substrate can be provided so as to be in direct contact with each other.

In the optical laminate 1, the angle between the absorption axis of the polarizing layer 12 and the slow axis of the retardation layer 13 is preferably within the range of 45°±5°. The angle may be within the range of 45°±3° and may be 45°.

The optical layered body 1, like the optical layered body 5 shown in FIG. It can also be used as an intermediate for producing a laminate containing, in this order, the vertically aligned liquid crystal layer 17 (FIG. 3) in which the polymerizable liquid crystal compound is cured in an aligned state. In this case, the laminate can be manufactured by providing the vertically aligned liquid crystal layer 17 on the retardation layer 13 side of the optical laminate 1 .

The optical layered body 1 can be used for a display device, and can be particularly preferably used for an organic EL display device. In the display device, the optical layered body 1 is arranged so that the dye-containing layer 11 is located on the viewing side of the polarizing layer 12 . The optical layered body 1 includes a dye-containing layer 11 that satisfies the relationships of formulas (1) and (2) described below. Therefore, in the display device in which the optical layered body 1 is incorporated in the arrangement described above, the coloration of the black image displayed on the panel when viewed from an oblique direction can be canceled by the dye-containing layer 11. As a result, it is possible to reduce the coloring of the black image when the display device is viewed obliquely.

(Dye-containing layer)
The dye-containing layer 11 contains a dichroic dye having a maximum absorption in the wavelength range of 400 nm or more and 750 nm or less, and satisfies the following formulas (1) and (2).
0.001≤AxC≤0.3 (1)
AxC (z = 60) / AxC>2 (2) [in formulas (1) and (2),
AxC is the absorbance of the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer 11, and represents the absorbance of linearly polarized light vibrating in the x-axis direction,
AxC (z=60) is the absorbance of the dye-containing layer 11 at the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less, and is the x-axis when the dye-containing layer 11 is rotated 60° with the y-axis as the rotation axis. represents the absorbance of linearly polarized light oscillating in the direction,
The x-axis represents an arbitrary direction within the plane of the dye-containing layer 11 , and the y-axis represents the direction perpendicular to the x-axis within the plane of the dye-containing layer 11 . ]

All absorbances in this specification represent absorbances measured in a state where the influence of interfacial reflection is excluded during measurement. As a method of removing the influence of interface reflection, for example, using a spectrophotometer, the absorbance at a wavelength at which the absorption of the compound is negligible in a long wavelength region such as a wavelength of 800 nm is set to 0, and in that state, the absorption of the compound exists. A method such as measuring the absorbance of a wavelength can be used.

The dye-containing layer 11 contains at least one kind of dichroic dye (hereinafter sometimes referred to as "the present dichroic dye") having a maximum absorption in the wavelength range of 400 nm or more and 750 nm or less. A dichroic dye is a dye that has different absorbances in the long-axis direction and the short-axis direction of the molecule. Since the dye-containing layer 11 satisfies the above formulas (1) and (2), the present dichroic dye is considered to be oriented in the lamination direction of the optical laminate 1 in the dye-containing layer 11. be done. The dye-containing layer 11 may contain a dichroic dye other than the present dichroic dye.

When the panel of the organic EL display device provided with the circularly polarizing plate is viewed from an oblique direction, the black image may appear colored. This is because the retardation layer included in the circularly polarizing plate functions outside the ideal retardation value. In addition, since metal electrodes are incorporated inside the panel of the organic EL display device, when the organic EL display device is viewed from an oblique direction, the phase difference of the reflected light obliquely reflected on the surface of the metal electrode is to be influenced. Therefore, when the organic EL display device is viewed from an oblique direction, a black image is colored in a different color for each target panel.

The optical layered body 1 of the present embodiment includes a dye-containing layer containing a dichroic dye as the dichroic dye having a light absorption ability capable of canceling the coloration of the panel when black is displayed when the display device is viewed from an oblique direction. 11. Therefore, in a display device incorporating the optical layered body 1, the hue difference between the front reflection hue and the oblique reflection hue can be reduced during black display. For example, the dye-containing layer 11 is arranged so that the reflected hue of the dye-containing layer 11 when viewed from the same direction is complementary to the hue when the panel is viewed from an oblique direction of 45° when the panel displays black. adjust the maximum absorption wavelength at 400-750 nm. Thereby, the coloring when the display device including the optical layered body 1 is viewed from an oblique direction of 45° can be canceled. Therefore, the oblique reflection hue can be improved without affecting the front reflection hue during black display of the display device, and the hue difference between the front reflection hue and the oblique reflection hue can be suppressed. Coloring of a black image can be reduced when the device is viewed from an oblique direction.

AxC in the above formulas (1) and (2) is the x-axis direction toward the surface of the dye-containing layer 11 from the thickness direction of the dye-containing layer 11 (hereinafter sometimes referred to as “z-axis direction”). can be measured by incident linearly polarized light oscillating at The above formula (1) is such that the absorbance in the front direction of the dye-containing layer 11 (the direction orthogonal to the surface of the dye-containing layer 11 and the stacking direction of the optical laminate 1) is 0.001 or more and 0.3 or less. It can be said that the smaller the value of AxC, the more accurately the dichroic dye is oriented in the stacking direction of the optical layered body 1 with respect to the surface of the dye-containing layer 11 . When AxC exceeds 0.3, the coloration in the front direction of the dye-containing layer 11 is strong, and the combination with the retardation layer 13 inhibits front light emission of the display device. Therefore, AxC is preferably 0. .1 or less, more preferably 0.05 or less. Also, the lower limit of AxC is usually 0.001 or more, preferably 0.003 or more, and more preferably 0.005 or more.

AxC (z = 60) in the above formula (2) is measured by inputting the same linearly polarized light as that for measuring AxC with the dye-containing layer 11 rotated by 60° with the y-axis as the rotation axis. can do. Here, the dye-containing layer 11 is rotated by rotating the dye-containing layer 11 in the state where AxC is measured by 60° in the incident direction of the linearly polarized light with the y-axis as the rotation axis. When AxC (z=60)/AxC is 2 or less, it becomes difficult to obtain good light absorption anisotropy, and in particular, light emission from the front of the display device may be hindered. AxC (z=60)/AxC is preferably 2.5 or more, more preferably 3 or more. On the other hand, if AxC (z = 60)/AxC is too large, light emission may be inhibited particularly when the display device is viewed from an oblique direction. It is more preferably 30 or less, still more preferably 20 or less. In addition, AxC (z = 60) is preferably 0.01 or more, more preferably 0.05 or more, still more preferably 0.10 or more, and preferably 1.0 or less, It is more preferably 0.5 or less, still more preferably 0.3 or less.

In addition, in the dye-containing layer 11 of the present specification, the absorbance AyC of linearly polarized light vibrating in the y-axis direction is generally approximately equal to AxC. If AxC and AyC are different, they will have in-plane dichroism, and in this case, the front emission of the display device may be particularly hindered.

When the dye-containing layer 11 satisfies the above formulas (1) and (2), it can be said that the dye-containing layer 11 has excellent polarizing performance (absorption anisotropy). It can transmit and effectively absorb light from oblique directions. Therefore, in the display device in which the optical layered body 1 including the dye-containing layer 11 is incorporated, the hue difference between the front reflection hue and the oblique reflection hue in black display can be suppressed without hindering the front emission of the display device. can be done.

AxC and AxC (z = 60) of the dye-containing layer 11 are, for example, the thickness of the dye-containing layer 11, the conditions of the manufacturing process, the type and/or amount of the present dichroic dye contained in the dye-containing layer 11, and the like. can be controlled by adjusting As will be described later, when the dye-containing layer 11 contains a cured product in which the polymerizable liquid crystal compound is oriented in the lamination direction of the optical laminate 1, AxC and AxC (z = 60) are the polymerizable liquid crystal compounds. It can also be controlled by adjusting the type and/or blending amount, and can be controlled by the host-guest interaction between the above cured product (liquid crystal) and the present dichroic dye. The value of AxC (z = 60)/AxC is about 2 to 10 when the polymerizable liquid crystal compound is a nematic liquid crystal, and about 5 to 30 when it is a smectic liquid crystal, and is appropriately selected according to the desired optical properties. It is possible.

As described above, in the display device in which the optical layered body 1 is incorporated so that the dye-containing layer 11 is on the viewer side of the polarizing layer 12, the dye-containing layer 11 has a front reflection hue and an oblique reflection hue in black display. can be used to suppress the hue difference between By arranging the dye-containing layer 11 closer to the viewing side than the polarizing layer 12 in the display device, even if the dye-containing layer 11 has a retardation in the thickness direction, it is not recognized by human eyes. Therefore, the dye-containing layer 11 may have retardation in the thickness direction, and the magnitude of the value is not particularly limited. Therefore, it is possible to adjust the thickness of the dye-containing layer 11 and the concentration of the present dichroic dye so as to satisfy the formulas (1) and (2) without being restricted by the retardation value in the thickness direction of the dye-containing layer 11. can. Thus, by using the optical layered body 1, it is possible to easily suppress the hue difference between the front reflection hue and the oblique reflection hue in black display.

Various colors are produced when the retardation layer 13 functions outside the ideal retardation value. For example, the color is often changed to red or blue. For this reason, in a display device in which a panel and an optical laminate 1 are combined, in order to easily adjust the oblique reflection hue when observed from an oblique direction to a desired hue, the dye-containing layer 11 has the following [a1] to Any one of [a3] is preferably satisfied.
[a1] having maximum absorption in both the wavelength range of 400 nm or more and less than 550 nm and the wavelength range of 550 nm or more and less than 700 nm;
[a2] has a maximum absorption in a wavelength range of 400 nm or more and less than 550 nm, and does not have a maximum absorption in a wavelength range of 550 nm or more and 700 nm or less;
[a3] It has no maximum absorption in the wavelength range of 400 nm or more and less than 550 nm, but has maximum absorption in the wavelength range of 550 nm or more and 700 nm or less.

When the dye-containing layer 11 satisfies the above [a3], it is possible to absorb reflected light leaking from an oblique direction. a2] is preferably used. When the dye-containing layer 11 satisfies the above [a2], by using the dye-containing layer 11 in combination with an elliptically polarizing plate that significantly reflects light in the wavelength range of 400 nm or more and less than 550 nm during black display at an oblique angle of 45°, It is possible to improve the oblique reflection hue during black display of the display device. When the dye-containing layer 11 satisfies the above [a3], the dye-containing layer 11 should be used in combination with an elliptically polarizing plate that significantly reflects light in the wavelength range of 550 nm or more and 700 nm or less when black is displayed at an angle of 45°. Thus, the oblique reflection hue during black display of the display device can be improved.

The dye-containing layer 11 preferably contains a cured product in which the polymerizable liquid crystal compound is oriented in the stacking direction of the optical layered body 1 . By containing the cured product, the dichroic dye can be easily oriented in the lamination direction of the optical laminate 1 in the cured film formed by the cured product, so that the dye-containing layer 11 can be easily produced. Details of the dichroic dye and the polymerizable liquid crystal compound will be described later.

The thickness of the dye-containing layer 11 is not particularly limited, and can be appropriately selected according to the structure of the display device. The thickness of the dye-containing layer 11 is preferably 0.1 μm or more, more preferably 0.2 μm or more, and preferably 10 μm or less, more preferably 3 μm or less, and still more preferably 2 μm or less. be.

(polarizing layer)
The polarizing layer 12 is a linear polarizing layer having a property of transmitting linearly polarized light having a vibration plane perpendicular to the absorption axis when non-polarized light is incident. Examples of the polarizing layer 12 include a stretched film to which a dye having anisotropic absorption is adsorbed, a film including a polarizing layer formed by coating a base film with a composition containing a dye having anisotropic absorption, and the like. Details of the polarizing layer 12 will be described later.

(retardation layer)
The retardation layer 13 has an in-plane retardation. The in-plane retardation value of the retardation layer 13 is not particularly limited, but the in-plane retardation value ReA (550) of the retardation layer 13 at a wavelength of 550 nm is preferably 50 nm or more, and is preferably 90 nm or more. more preferred. ReA(550) of the retardation layer 13 is more preferably in the range of 100 nm or more and 250 nm or less, and particularly preferably in the range of the following formula (4).
120 nm≦ReA(550)≦170 nm (4)
[In formula (4), ReA(550) represents an in-plane retardation value of the retardation layer 13 at a wavelength of 550 nm. ]

By setting the in-plane retardation ReA (550) of the retardation layer 13 within the range of the above formula (4), the effect of improving the front reflection hue during black display of the display device incorporating the optical layered body 1 ( effect of suppressing coloration) becomes remarkable. The in-plane retardation value ReA(550) is more preferably 130 nm or more, and more preferably 150 nm or less.

The retardation layer 13 may be, for example, a stretched film having an in-plane retardation. It may be a cured product layer (hereinafter sometimes referred to as a "horizontally aligned liquid crystal layer") in which the compound is cured in an aligned state. The retardation layer 13 is preferably a horizontally aligned liquid crystal layer because the retardation layer 13 can be easily controlled to have a desired in-plane retardation value and can be made thinner.

The retardation layer 13 preferably satisfies the relationship of formula (3) below.
ReA(450)/ReA(550)<1.00 (3)
[In formula (3), ReA(450) and ReA(550) represent in-plane retardation values of the retardation layer 13 at wavelengths of 450 nm and 550 nm, respectively. ]

Here, the in-plane retardation value ReA(λ) of the retardation layer 13 at the wavelength λ is represented by the following formula (6).
ReA(λ)=(nxA(λ)−nyA(λ))×dA (6)
[In formula (6),
nxA(λ) represents the principal refractive index at a wavelength λnm in the plane of the retardation layer 13,
nyA (λ) represents the refractive index at a wavelength λ nm in a direction orthogonal to the direction of nxA (λ) in the same plane as nxA (λ),
dA indicates the thickness of the retardation layer 13 . ]

When the retardation layer 13 satisfies the relationship of the above formula (3), the retardation layer 13 has an in-plane retardation value at short wavelengths smaller than an in-plane retardation value at long wavelengths, that is, so-called reverse wavelength dispersion. show gender. From the viewpoint of improving reverse wavelength dispersion, ReA(450)/ReA(550) is preferably 0.70 or more, more preferably 0.78 or more, and preferably 0.95 or less, more preferably 0.92 or less.

The in-plane retardation value ReA(λ) can be adjusted by the thickness dA of the retardation layer 13 . Since the in-plane retardation value ReA(λ) is determined by the above equation (6), a desired in-plane retardation value can be obtained by adjusting the three-dimensional refractive index and the film thickness dA.

When the retardation layer 13 is a stretched film, the thickness of the retardation layer 13 is usually 5 μm or more and 200 μm or less, preferably 10 μm or more and 80 μm or less, more preferably 40 μm or less. When the retardation layer 13 is a horizontally aligned liquid crystal layer, the thickness of the retardation layer 13 is preferably 0.1 μm or more, more preferably 0.2 μm or more, and preferably 3 μm or less. It is preferably 2 μm or less.

The retardation layer 13 is a combination of a layer having a retardation characteristic of λ/4 and a layer having a retardation characteristic of λ/2. By stacking the layers, the in-plane retardation value ReA (550) as a whole satisfies the relationship of the above formula (4), and ReA (450) / ReA (550) satisfies the relationship of the above formula (3) may be When the retardation layer 13 is a laminate in which a layer having a retardation characteristic of λ/4 and a layer having a retardation characteristic of λ/2 are laminated, for example, the angle formed by the slow axes of each layer is 50. It is possible to suitably use those laminated so as to have an angle of 70° or more.

Details of the material forming the retardation layer 13, the method of forming the retardation layer 13, and the like will be described later.

(Method for manufacturing optical laminate)
FIG. 2 is a schematic diagram schematically showing an example of a method for manufacturing the optical layered body 1 shown in FIG. The optical layered body 1 shown in FIG. 1 can be manufactured by laminating each of the above-described layers via bonding layers as necessary. As shown in FIG. 2, when the optical layered body 1 is manufactured by a so-called roll-to-roll method, in which a long film is laminated while being continuously conveyed, for example, the first layer including the dye-containing layer 11 and the polarizing layer 12 The laminated body 20 and the retardation layer 13 may be bonded via a bonding layer while being continuously transported in the direction of the arrow in FIG. When the retardation layer 13 is a horizontally aligned liquid crystal layer, a layered body having a horizontally aligned liquid crystal layer on a substrate and the first layered body 20 may be bonded together.

By manufacturing the optical layered body 1 by roll-to-roll, the manufacturing process of the optical layered body 1 can be shortened, and the optical layered body 1 which is excellent in visibility by preventing foreign matter from entering between layers. can be manufactured.

(Display device)
The optical layered body 1 can be used for a display device. As the display device, an organic EL display device is preferable. The optical layered body 1 is provided on the viewing side of the panel of the display device, and in the display device, the dye-containing layer 11 is preferably arranged on the viewing side rather than the polarizing layer 12 . Accordingly, it is possible to provide a display device that suppresses the hue difference between the front reflection hue and the oblique reflection hue in black display.

[Embodiment 2]
(Optical laminate)
FIG. 3 is a cross-sectional view schematically showing an optical laminate according to another embodiment of the invention. As shown in FIG. 3, the optical laminate 5 includes a dye-containing layer 11, a polarizing layer 12, a retardation layer 13 having an in-plane retardation, and a vertically aligned liquid crystal layer 17 in this order. The optical layered body 5 preferably forms an elliptically polarizing plate (including a circularly polarizing plate) with the polarizing layer 12 and the retardation layer 13 . The optical laminate 5 may further have a hard coat layer 16 or a protective film 15 on the opposite side of the dye-containing layer 11 from the polarizing layer 12 side. The optical layered body 5 shown in FIG. 3 has the hard coat layer 16 and the protective film 15 at the same time. When the optical laminate 5 has the hard coat layer 16 and the protective film 15 at the same time, it is preferable to have the protective film 15 and the hard coat layer 16 in this order from the dye-containing layer 11 side.

Each layer constituting the optical layered body 5 is preferably laminated via a bonding layer which is a pressure-sensitive adhesive layer or an adhesive layer. When the optical layered body 5 has the hard coat layer 16 and the protective film 15 at the same time, it is preferable that the protective film 15 and the hard coat layer 16 are provided so as to be in direct contact with each other without a bonding layer interposed therebetween. The optical laminate 5 may have an adhesive layer between the retardation layer 13 and the vertically aligned liquid crystal layer 17, and the adhesive layer may be in direct contact with the retardation layer 13 and the vertically aligned liquid crystal layer 17. preferable. The adhesive layer is preferably a cured product layer of an ultraviolet curable adhesive composition which will be described later.

When the dye-containing layer 11, the polarizing layer 12, the retardation layer 13, and the vertically aligned liquid crystal layer 17 are layers formed using a liquid crystal compound such as a polymerizable liquid crystal compound, the optical laminate 5 contains the above liquid crystal compound. It may have an alignment film for regulating the alignment of the liquid crystal compound so as to be in direct contact with the layer formed using the liquid crystal compound. may have The layer or alignment film formed using the liquid crystal compound and the substrate can be provided so as to be in direct contact with each other.

In the optical laminate 5, the angle between the absorption axis of the polarizing layer 12 and the slow axis of the retardation layer 13 is preferably within the range of 45°±5°. The angle may be within the range of 45°±3° and may be 45°.

The optical layered body 5 can be used in a display device, and can be particularly preferably used in an organic EL display device. In the display device, the optical layered body 5 is arranged so that the dye-containing layer 11 is located on the viewing side of the polarizing layer 12 . In the display device in which the optical layered body 5 is incorporated in such an arrangement, it is possible to improve the degree of coloration (diagonal reflection hue) of reflected light from oblique directions of the display device during black display.

The dye-containing layer 11, the polarizing layer 12, and the retardation layer 13 can be those described in the previous embodiment, and their arrangement can also be as described in the previous embodiment.

(Vertical alignment liquid crystal layer)
The vertically aligned liquid crystal layer 17 is a cured product layer cured with the polymerizable liquid crystal compound aligned in the stacking direction of the optical layered body 5 . The vertically aligned liquid crystal layer 17 may contain a dichroic dye, but preferably does not contain at least the present dichroic dye, and more preferably does not contain any dichroic dye.

Here, the retardation value RthC(λ) in the thickness direction of the vertically aligned liquid crystal layer 17 at the wavelength λ is represented by the following formula (7).
RthC(λ)
= ((nxC(λ)+nyC(λ))/2−nzC(λ))×dC (7)
[In formula (7),
nxC(λ) represents the principal refractive index at a wavelength λnm in the plane of the vertically aligned liquid crystal layer 17,
nyC(λ) represents the refractive index at a wavelength λ nm in the same plane as nxC(λ) and in a direction perpendicular to nxC(λ),
nzC(λ) represents the refractive index at wavelength λnm in the thickness direction of the vertically aligned liquid crystal layer 17, and when nxC(λ)=nyC(λ), nxC(λ) is the surface of the vertically aligned liquid crystal layer 17 can be the index of refraction in any direction within
dC indicates the film thickness of the vertically aligned liquid crystal layer 17 . ]

RthC(450)/RthC(550) is not particularly limited, preferably 0.70 or more, more preferably 0.75 or more, still more preferably 0.80 or more, and 1.00 or more. 1.10 or more, or 1.20 or more. Also, it is preferably 0.95 or less, more preferably 0.92 or less, and particularly preferably 0.90 or less.

In the vertically aligned liquid crystal layer 17, it is preferable that the polymerizable liquid crystal compound is highly ordered in the stacking direction. As a result, the effect of improving the oblique reflection hue during black display of the display device incorporating the optical layered body 5 can be enhanced. In order to easily obtain this effect, RthC(550) of the vertically aligned liquid crystal layer 17 is preferably in the range of −120 nm or more and −30 nm or less. From the viewpoint of further improving the above effects, RthC(550) of the vertically aligned liquid crystal layer 17 is more preferably −100 nm or more, still more preferably −90 nm or more, and particularly preferably −80 nm or more. It is more preferably −40 nm or less, still more preferably −50 nm or less.

The retardation value RthC(λ) in the thickness direction can be adjusted by the thickness dC of the vertically aligned liquid crystal layer 17 . Since the retardation value RthC(λ) in the thickness direction is determined by the above formula (7), in order to obtain the desired retardation value RthC(λ) in the thickness direction, the three-dimensional refractive index and the film thickness dC should be adjusted.

As described above, in the display device in which the optical layered body 5 is incorporated so that the dye-containing layer 11 is located on the viewing side of the polarizing layer 12, the vertically aligned liquid crystal layer 17 causes oblique reflection during black display of the display device. Can be used to improve hue. Therefore, in the display device incorporating the optical layered body 5, the oblique reflection hue during black display of the display device can be improved.

On the other hand, except that the dye-containing layer 11 is not provided and a layer containing the dichroic dye in the vertically aligned liquid crystal layer 17 (hereinafter sometimes referred to as a "dye-containing liquid crystal layer") is used. Even if a laminate having a layer structure similar to that of the laminate 5 is used, the oblique reflection hue during black display of the display device can be improved. However, the absorbance and absorption wavelength of the dye-containing liquid crystal layer and the retardation value Rth in the thickness direction of the dye-containing liquid crystal layer are mutually related parameters. Therefore, for example, if only the thickness of the dye-containing liquid crystal layer is increased or decreased in order to adjust the retardation value Rth in the thickness direction of the dye-containing liquid crystal layer, a large increase or decrease also occurs in the absorbance. Coloring may be confirmed when viewed from an oblique angle. Further, for example, when the concentration of the dichroic dye contained in the dye-containing liquid crystal layer is changed in order to adjust the absorbance of the dichroic dye, the retardation value Rth in the thickness direction of the dye-containing liquid crystal layer fluctuates, This may cause a decrease in contrast when viewed from an oblique direction during black display on the display device. Furthermore, since the phase difference of the reflected light obliquely reflected on the surface of the metal electrode varies depending on the type of the panel of the display device, the optimum thickness direction retardation value Rth varies. need to adjust accordingly. Therefore, in order to improve the oblique reflection hue using only the dye-containing liquid crystal layer, it is necessary to adjust the thickness of the dye-containing liquid crystal layer and the concentration of the dichroic dye according to the structure of the display device. There is a problem that the production of the containing liquid crystal layer becomes complicated.

On the other hand, in the optical laminate 5 of the present embodiment, the dye-containing layer 11 absorbs colored light from an oblique direction, and the vertically aligned liquid crystal layer 17 absorbs the oblique direction of the retardation layer 13 by the retardation value Rth in the thickness direction. The reflection hue is improved by adjusting the retardation value of . Thus, in the optical layered body 5, two independent layers share the two functions described above. Therefore, when adjusting the absorbance and absorption wavelength, the dye-containing layer 11 may be adjusted, and when adjusting the retardation value Rth in the thickness direction, the vertically aligned liquid crystal layer 17 may be adjusted. Thus, in the optical layered body 5, the above two functions can be independently adjusted in two independent layers. Compared to the case of adjustment, the above two functions can be easily adjusted.

(Method for manufacturing optical laminate)
The optical layered body 5 shown in FIG. 3 can be manufactured by laminating the optical layered body 1 shown in FIG. 1 and the vertically aligned liquid crystal layer 17 via a bonding layer. The lamination layer is preferably an adhesive layer, more preferably a cured product layer of an ultraviolet curable adhesive composition. The optical layered body 5 may be obtained by laminating the optical layered body 1 and a layered body in which the vertically aligned liquid crystal layer 17 is provided on the substrate. The optical layered body 5 is preferably manufactured by roll-to-roll, like the optical layered body 1 (FIG. 2) described in the previous embodiment.

(Display device)
The optical laminate 5 can be used for display devices. As the display device, an organic EL display device is preferable. The optical layered body 5 is provided on the viewing side of the panel of the display device, and is preferably arranged so that the dye-containing layer 11 is closer to the viewing side than the polarizing layer 12 in the display device. Accordingly, it is possible to provide a display device that suppresses the hue difference between the front reflection hue and the oblique reflection hue in the black display of the display device.

[Embodiment 3]
(Optical laminate)
4 and 5 are cross-sectional views schematically showing an optical layered body according to still another embodiment of the present invention.

As shown in FIG. 4, the optical layered body 6 includes a dye-containing layer 11, a polarizing layer 12, and a retardation layer 13 having an in-plane retardation in this order. The optical laminate 6 preferably forms an elliptically polarizing plate (including a circularly polarizing plate) with the polarizing layer 12 and the retardation layer 13 . The optical laminate 6 may further have a first hard coat layer 16 and/or a first protective film 15 on the opposite side of the dye-containing layer 11 from the polarizing layer 12 side. The first hard coat layer 16 and the first protective film 15 respectively correspond to the hard coat layer 16 and protective film 15 described in the previous embodiment. The optical layered body 6 shown in FIG. 4 has the first hard coat layer 16 and the first protective film 15 at the same time. When the optical laminate 6 has the first hard coat layer 16 and the first protective film 15 at the same time, as shown in FIG. It is preferable to have

Each layer constituting the optical layered body 6 is preferably laminated via a bonding layer which is a pressure-sensitive adhesive layer or an adhesive layer. When the optical laminate 6 has the first hard coat layer 16 and the first protective film 15 at the same time, the first protective film 15 and the first hard coat layer 16 are provided so as to be in direct contact with each other without a bonding layer interposed therebetween. preferably.

The optical laminate 6 shown in FIG. 4 further has a second hard coat layer 162 and a second protective film 152 in order from the dye-containing layer 11 side between the dye-containing layer 11 and the polarizing layer 12 . It is preferable that the second hard coat layer 162 and the second protective film 152 are provided so as to be in direct contact with each other without an intervening bonding layer. The second hard coat layer 162 is usually laminated on the dye-containing layer 11 via a bonding layer. The second protective film 152 is usually laminated on the polarizing layer 12 via a bonding layer. The lamination layer is a pressure-sensitive adhesive layer or an adhesive layer. The second hard coat layer 162, the second protective film 152, and the polarizing layer 12 can constitute a polarizing plate.

The optical laminate 6 includes a first hard coat layer 16 on the side of the dye-containing layer 11 opposite to the polarizing layer 12 side with a first protective film 15 interposed therebetween, and a first hard coat layer 16 on the side of the dye-containing layer 11 on the polarizing layer 12 side. 2 hard coat layer 162 and second protective film 152 are provided in this order. In such an optical laminate 6, the first hard coat layer 16 is laminated on the first protective film 15 from the viewpoint of improving the crack resistance of the dye-containing layer 11 against impact from the first hard coat layer 16 side. Preferably, the pencil hardness is HB to 6B in the state, and the pencil hardness of the second hard coat layer 162 in the state laminated on the second protective film 152 is HB to 6B. The pencil hardness of the first hard coat layer 16 and the pencil hardness of the second hard coat layer 162 may be the same. Alternatively, the pencil hardness of the first hard coat layer 16 may be softer or harder than the pencil hardness of the second hard coat layer 162 . When the pencil hardness of the first hard coat layer 16 and the pencil hardness of the second hard coat layer 162 are different, the difference is usually 6 levels or less, but from the viewpoint of further improving the crack resistance, it is 2 levels or more. is preferred.

The optical layered body 6 may further have a third hard coat layer between the dye-containing layer 11 and the polarizing layer 12 . When the optical laminate 6 has the second hard coat layer 162 and the second protective film 152 , a third hard coat layer can be provided between the dye-containing layer 11 and the second hard coat layer 162 . The third hard coat layer can be provided in direct contact with the dye-containing layer 11 or the alignment film that is in direct contact with the dye-containing layer 11, and the third hard coat layer and the polarizing layer 12 or the second hard coat layer 162 are preferably laminated via a bonding layer. The bonding layer is preferably in direct contact with the polarizing layer 12 or the second hard coat layer 162 and the third hard coat layer. The pencil hardness of the third hard coat layer may be the same as or different from that of the first hard coat layer 16 or the second hard coat layer 162 .

The optical layered body 6 shown in FIG. 4 can be used for a display device. The optical layered body 6 includes, on the retardation layer 13 side of the optical layered body 6, a vertically aligned liquid crystal layer 17 cured in a state in which the polymerizable liquid crystal compound is aligned in the layering direction of the optical layered body 6 in this order. It can also be used as a production intermediate of (FIG. 5).

The optical layered body 7 shown in FIG. 5 has a structure in which the optical layered body 6 and the vertically aligned liquid crystal layer 17 are laminated. In the optical layered body 7, the vertically aligned liquid crystal layer 17 is preferably laminated on the retardation layer 13 side of the optical layered body 6 via a bonding layer that is an adhesive layer or an adhesive layer.

The optical layered bodies 6 and 7 can be used in display devices, and can be particularly suitably used in organic EL display devices. In the display device, the optical layered bodies 6 and 7 are arranged so that the dye-containing layer 11 is located on the viewing side of the polarizing layer 12 . In the display device in which the optical layered body 6 is incorporated in the arrangement described above, the coloration of the black image displayed on the panel when viewed from an oblique direction can be canceled by the dye-containing layer 11 . As a result, it is possible to reduce the coloring of the black image when the display device is viewed obliquely. Further, in the display device in which the optical layered body 7 is incorporated in the above-described arrangement, it is possible to improve the coloring degree of the reflected light from the oblique direction of the display device (diagonal reflection hue) during black display.

The dye-containing layer 11, the polarizing layer 12, the retardation layer 13, and the vertically aligned liquid crystal layer 17 can be those described in the previous embodiment, and their arrangement can also be as described in the previous embodiment. can be done.

(Method for manufacturing optical laminate)
The optical layered body 6 shown in FIG. 4 and the optical layered body 7 shown in FIG. 5 can be produced by laminating each of the layers described above via bonding layers as necessary. The optical laminate 6 is, for example, a second laminate including a first hard coat layer 16, a first protective film 15, a dye-containing layer, and optionally a third hard coat layer, and a second hard coat layer 162, the second protective film 152, and the polarizing plate including the polarizing layer 12 are laminated via bonding layers to obtain a third laminate. Next, the optical laminate 6 can be obtained by laminating the third laminate and the retardation layer 13 via a bonding layer. The optical layered body 7 can be manufactured by laminating the optical layered body 6 and the vertically aligned liquid crystal layer 17 via a bonding layer. The optical layered body 7 may be obtained by laminating the optical layered body 6 and a layered body in which the vertically aligned liquid crystal layer 17 is provided on the substrate. The optical layered bodies 6 and 7 are preferably manufactured by roll-to-roll, like the optical layered body 1 described in the previous embodiment (FIG. 2).

(Display device)
The optical laminates 6 and 7 can be used in display devices. As the display device, an organic EL display device is preferable. The optical laminates 6 and 7 are provided on the viewing side of the panel of the display device, and are preferably arranged so that the dye-containing layer 11 is located on the viewing side of the polarizing layer 12 in the display device. Accordingly, it is possible to provide a display device that suppresses the hue difference between the front reflection hue and the oblique reflection hue in the black display of the display device.

Details of each member used in the optical layered body of the present embodiment, a method for manufacturing the same, and the like will be described below.
(Present dichroic dye)
The dichroic dye contained in the dye-containing layer is not particularly limited as long as it is a dichroic dye having a maximum absorption in the wavelength range of 400 nm or more and 750 nm or less. The dichroic dye may be a dye or a pigment. The dichroic dye contained in the dye-containing layer may be a combination of two or more dyes, a combination of two or more pigments, or a combination of a dye and a pigment. .

Since the dye-containing layer preferably satisfies [a1] or [a2] described above, the present dichroic dye is a dye selected from acridine dyes, oxazine dyes, cyanine dyes, naphthalene dyes, azo dyes and anthraquinone dyes. is preferably used. Among them, it is more preferable to use an azo dye from the viewpoint of orientation. Further, the present dichroic dye may exhibit liquid crystallinity.

Examples of azo dyes include monoazo dyes, bisazo dyes, trisazo dyes, tetrakis azo dyes and stilbene azo dyes, and preferred are bisazo dyes and trisazo dyes. (i)” may be mentioned).
K ¹ (-N=N-K ² ) _p -N=N-K ³ (i)
[In the formula (i),
K ¹ and K ³ are each independently a phenyl group optionally having substituent(s), a naphthyl group optionally having substituent(s) or a monovalent heterocyclic group optionally having substituent(s) represents
K ² is a p-phenylene group optionally having substituents, a naphthalene-1,4-diyl group optionally having substituents or a divalent heterocyclic ring optionally having substituents represents a group.
p represents an integer of 1 to 4; When p is an integer of ² or more, multiple K2 may be the same or different.
-N=N-bonds may be replaced with -C=C-, -COO-, -NHCO- and -N=CH-bonds within the range of absorption in the visible region. ]

Examples of monovalent heterocyclic groups include groups obtained by removing one hydrogen atom from heterocyclic compounds such as quinoline, thiazole, benzothiazole, thienothiazole, imidazole, benzimidazole, oxazole, and benzoxazole. The divalent heterocyclic group includes a group obtained by removing two hydrogen atoms from the above heterocyclic compound.

Optional substituents of the phenyl group, naphthyl group and monovalent heterocyclic group for K ¹ and K ³ and the p-phenylene group, naphthalene-1,4-diyl group and divalent heterocyclic group for K ² is an alkyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms having a polymerizable group, an alkenyl group having 1 to 4 carbon atoms; alkoxy group; alkoxy group having 1 to 20 carbon atoms having a polymerizable group; fluorinated alkyl group having 1 to 4 carbon atoms such as trifluoromethyl group; cyano group; nitro group; halogen atom; amino group, diethylamino group, pyrrolidino A substituted or unsubstituted amino group such as a group (a substituted amino group is an amino group having one or two alkyl groups having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms having a polymerizable group) or an amino group having two, or an amino group in which two substituted alkyl groups are bonded together to form an alkanediyl group having 2 to 8 carbon atoms.An unsubstituted amino group is —NH _2. ) etc. Here, examples of the polymerizable group include an acryloyl group, a methacryloyl group, an acryloyloxy group, and a methacryloyloxy group.

［式（ｉ－１）～（ｉ－８）中、
Ｂ^１～Ｂ^３０は、互いに独立して、水素原子、炭素数１～６のアルキル基、炭素数１～６のアルケニル基、炭素数１～４のアルコキシ基、シアノ基、ニトロ基、置換又は無置換のアミノ基（置換アミノ基及び無置換アミノ基の定義は上記のとおり）、塩素原子又はトリフルオロメチル基を表す。
ｎ１～ｎ４は、互いに独立に０～３の整数を表す。
ｎ１が２以上である場合、複数のＢ^２は互いに同一でも異なっていてもよく、
ｎ２が２以上である場合、複数のＢ^６は互いに同一でも異なっていてもよく、
ｎ３が２以上である場合、複数のＢ^９は互いに同一でも異なっていてもよく、
ｎ４が２以上である場合、複数のＢ^１４は互いに同一でも異なっていてもよい。］ Among compounds (i), compounds represented by any one of the following formulas (i-1) to (i-8) are preferred.

[In the formulas (i-1) to (i-8),
B ¹ to B ³⁰ each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, a nitro group, substituted or represents an unsubstituted amino group (the definitions of a substituted amino group and an unsubstituted amino group are as described above), a chlorine atom or a trifluoromethyl group;
n1 to n4 each independently represents an integer of 0 to 3;
When n1 is ² or more, the plurality of B2 may be the same or different,
When n2 is 2 or more, the plurality of ^B6 may be the same or different,
When n3 is ² or more, multiple B9 may be the same or different,
When n4 is 2 or more, the plurality of ^B14 may be the same or different. ]

［式（ｉ－９）中、
Ｒ^１～Ｒ^８は、互いに独立して、水素原子、－Ｒ^ｘ、－ＮＨ_２、－ＮＨＲ^ｘ、－ＮＲ^ｘ _２、－ＳＲ^ｘ又はハロゲン原子を表す。
Ｒ^ｘは、炭素数１～４のアルキル基又は炭素数６～１２のアリール基を表す。］ As the anthraquinone dye, a compound represented by formula (i-9) is preferred.

[In the formula (i-9),
R ¹ to R ⁸ independently represent a hydrogen atom, —R ^x , —NH ₂ , —NHR ^x , —NR ^x ₂ , —SR ^x or a halogen atom.
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

［式（ｉ－１０）中、
Ｒ^９～Ｒ^１５は、互いに独立して、水素原子、－Ｒ^ｘ、－ＮＨ_２、－ＮＨＲ^ｘ、－ＮＲ^ｘ _２、－ＳＲ^ｘ又はハロゲン原子を表す。
Ｒ^ｘは、炭素数１～４のアルキル基又は炭素数６～１２のアリール基を表す。］ As the oxazone dye, a compound represented by formula (i-10) is preferable.

[In formula (i-10),
R ⁹ to R ¹⁵ each independently represent a hydrogen atom, —R ^x , —NH ₂ , —NHR ^x , —NR ^x ₂ , —SR ^x or a halogen atom.
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

［式（ｉ－１１）中、
Ｒ^１６～Ｒ^２３は、互いに独立して、水素原子、－Ｒ^ｘ、－ＮＨ_２、－ＮＨＲ^ｘ、－ＮＲ^ｘ _２、－ＳＲ^ｘ又はハロゲン原子を表す。
Ｒ^ｘは、炭素数１～４のアルキル基又は炭素数６～１２のアリール基を表す。］ As the acridine dye, a compound represented by formula (i-11) is preferable.

[In the formula (i-11),
R ¹⁶ to R ²³ each independently represent a hydrogen atom, —R ^x , —NH ₂ , —NHR ^x , —NR ^x ₂ , —SR ^x or a halogen atom.
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

In formula (i-9), formula (i-10) and formula (i-11), the alkyl group having 1 to 6 carbon atoms for R ^x includes a methyl group, an ethyl group, a propyl group, a butyl group and a pentyl group. and a hexyl group, and examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, a toluyl group, a xylyl group, a naphthyl group, and the like.

［式（ｉ－１２）中、
Ｄ^１及びＤ^２は、互いに独立に、式（ｉ－１２ａ）～式（ｉ－１２ｄ）のいずれかで表される基を表す。

ｎ５は、１～３の整数を表す。］ As the cyanine dye, a compound represented by formula (i-12) and a compound represented by formula (i-13) are preferable.

[In the formula (i-12),
D ¹ and D ² each independently represent a group represented by any one of formulas (i-12a) to (i-12d).

n5 represents an integer of 1-3. ]

［式（ｉ－１３）中、
Ｄ^３及びＤ^４は、互いに独立に、式（ｉ－１３ａ）～式（ｉ－１３ｈ）のいずれかで表される基を表す。

ｎ６は、１～３の整数を表す。］

[In formula (i-13),
D ³ and D ⁴ each independently represent a group represented by any one of formulas (i-13a) to (i-13h).

n6 represents an integer of 1-3. ]

From the viewpoint of orientation, the dye-containing layer preferably contains at least one kind of azo dye as the present dichroic dye. The weight average molecular weight of the present dichroic dye is usually 300-2000, preferably 400-1000.

The content of the present dichroic dye in the composition forming the dye-containing layer can be appropriately determined according to the type of the present dichroic dye. When the dye-containing layer contains a cured product of a polymerizable liquid crystal compound, the content of the present dichroic dye in the composition is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. , more preferably 0.1 to 10 parts by mass, still more preferably 0.1 to 5 parts by mass. When the content of the present dichroic dye is within the above range, it is possible to control the absorbance so as to compensate for the reflected hue from oblique directions without impairing the white display of the display device. In addition, it is possible to obtain a cured product of a polymerizable liquid crystal compound having a high degree of alignment order without disturbing the alignment of the polymerizable liquid crystal compound.

(Polymerizable liquid crystal compound and polymerizable liquid crystal composition for forming dye-containing layer)
The dye-containing layer may contain a cured product in which the polymerizable liquid crystal compound is oriented in the lamination direction of the optical laminate. The polymerizable liquid crystal compound is a liquid crystal compound having a polymerizable group, and the polymerizable group is preferably a photopolymerizable group. The polymerizable liquid crystal compound is not particularly limited as long as it can form a dye-containing layer that satisfies the above formulas (1) and (2). For example, conventionally known polymerizable liquid crystal compounds in the field of retardation films are used. be able to.

A polymerizable group refers to a group that can participate in a polymerization reaction. A photopolymerizable group is a polymerizable group, and refers to a group that can participate in a polymerization reaction by a reactive species generated from a photopolymerization initiator, such as an active radical or an acid. Examples of photopolymerizable groups include vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloyloxy group, methacryloyloxy group, oxiranyl group and oxetanyl group. Among them, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxiranyl group, and an oxetanyl group are preferred, and an acryloyloxy group is more preferred. The liquid crystallinity exhibited by the polymerizable liquid crystal compound may be a thermotropic liquid crystal or a lyotropic liquid crystal, but the thermotropic liquid crystal is preferable because it enables precise film thickness control. The phase-ordered structure of the thermotropic liquid crystal may be nematic liquid crystal or smectic liquid crystal. From the viewpoint of reducing the value of AxC and increasing the value of AxC (z=60)/AxC in the above formulas (1) and (2), smectic liquid crystals are preferable. When the value of AxC is small and the value of AxC (z=60)/AxC is large, the oblique reflection hue can be effectively improved while maintaining good white display of the display device. A polymerizable liquid crystal compound can be used individually or in combination of 2 or more types.

Examples of the polymerizable liquid crystal compound generally include a polymerizable liquid crystal compound exhibiting forward wavelength dispersion and a polymerizable liquid crystal compound exhibiting reverse wavelength dispersion. Only one of the polymerizable liquid crystal compounds may be used, Both polymerizable liquid crystal compounds can be mixed and used.

The polymerizable liquid crystal compound exhibiting reverse wavelength dispersion is preferably a compound having the following characteristics (A) to (D).
(A) A compound capable of forming a nematic phase or a smectic phase.
(B) The polymerizable liquid crystal compound has π electrons along the longitudinal direction (a).
(C) It has π electrons in a direction crossing the major axis direction (a) [intersecting direction (b)].
(D) A polymerizable liquid crystal compound defined by the following formula (ia), where N (πa) is the total number of π electrons present in the longitudinal direction (a), and N (Aa) is the total molecular weight present in the longitudinal direction. π electron density in the long axis direction (a) of
D(πa)=N(πa)/N(Aa) (ia)
and a polymerizable liquid crystal compound defined by the following formula (iib), where N(πb) is the sum of π electrons present in the cross direction (b), and N(Ab) is the sum of the molecular weights present in the cross direction (b). π electron density in the cross direction (b) of
D(πb)=N(πb)/N(Ab) (iib)
is the formula (iii)
0≦[D(πa)/D(πb)]<1 (iiiic)
[that is, the π electron density in the cross direction (b) is higher than the π electron density in the long axis direction (a)]. In addition, as described above, a polymerizable liquid crystal compound having π electrons on the major axis and the direction crossing it has, for example, a T-shaped structure.

In the features (A) to (D) above, the major axis direction (a) and the number of π electrons N are defined as follows.
- The long axis direction (a) is, for example, the long axis direction of a rod-like structure in the case of a compound having a rod-like structure.
- The number of π electrons N (πa) present in the major axis direction (a) does not include π electrons that disappear due to the polymerization reaction.
The number of π electrons N (πa) present along the major axis direction (a) is the total number of π electrons on the major axis and π electrons conjugated therewith, for example, present along the major axis direction (a) It includes the number of π electrons present in a ring that satisfies Hückel's rule.
- The number of π electrons N (πb) existing in the cross direction (b) does not include π electrons that disappear due to the polymerization reaction.
A polymerizable liquid crystal compound satisfying the above has a mesogenic structure in the major axis direction. A liquid crystal phase (nematic phase, smectic phase) is expressed by this mesogenic structure.

A polymerizable liquid crystal compound satisfying the above (A) to (D) can form a nematic phase or a smectic phase by coating it on a substrate or an alignment film and heating it to a phase transition temperature or higher. In the nematic phase or smectic phase formed by aligning the polymerizable liquid crystal compound, the long axis directions of the polymerizable liquid crystal compound are usually oriented parallel to each other, and the long axis direction is the alignment direction of the nematic phase. becomes. When such a polymerizable liquid crystal compound is made into a film and polymerized in a nematic phase or smectic phase, a polymer film composed of a polymer oriented in the major axis direction (a) can be formed. . This polymer film absorbs ultraviolet rays by π electrons in the long axis direction (a) and π electrons in the cross direction (b). Let λbmax be the absorption maximum wavelength of ultraviolet rays absorbed by π electrons in the cross direction (b). λbmax is typically between 300 nm and 400 nm. The π-electron density satisfies the above formula (iiic), and the π-electron density in the cross direction (b) is higher than the π-electron density in the major axis direction (a). is greater than the absorption of linearly polarized UV light (wavelength: λbmax) having a plane of vibration in the major axis direction (a). The ratio (absorbance in cross direction (b) of linearly polarized ultraviolet rays/absorbance in major axis direction (a)) is, for example, more than 1.0, preferably 1.2 or more, and usually 30 or less. , for example 10 or less.

Polymerizable liquid crystal compounds having the above properties generally exhibit reverse wavelength dispersion in many cases. Specific examples thereof include compounds represented by the following formula (X).

In formula (X), Ar represents a divalent group having an optionally substituted aromatic group. The aromatic group as used herein refers to a ring structure having [4n+2] number of π electrons according to Hückel's rule, for example, as exemplified in (Ar-1) to (Ar-23) described later. may have two or more Ar groups via a divalent linking group. Here n represents an integer. When heteroatoms such as -N= and -S- are included to form a ring structure, the non-covalent electron pairs on these heteroatoms satisfy Hückel's rule and have aromaticity. At least one or more of a nitrogen atom, an oxygen atom and a sulfur atom are preferably contained in the aromatic group. The number of aromatic groups contained in the divalent group Ar may be one, or two or more. When there is one aromatic group, the divalent group Ar may be an optionally substituted divalent aromatic group. When the number of aromatic groups contained in the divalent group Ar is two or more, the two or more aromatic groups are bonded to each other via a single bond, -CO-O-, -O- or other divalent linking group. may be
G ¹ and G ² each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group. Here, the hydrogen atom contained in the divalent aromatic group or divalent alicyclic hydrocarbon group is a halogen atom, an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, a carbon may be substituted with an alkoxy group, cyano group or nitro group having a number of 1 to 4, and the carbon atoms constituting the divalent aromatic group or divalent alicyclic hydrocarbon group are oxygen atoms, sulfur atoms Alternatively, it may be substituted with a nitrogen atom.
L ¹ , L ² , B ¹ and B ² are each independently a single bond or a divalent linking group.
k and l each independently represents an integer of 0 to 3 and satisfies the relationship 1≦k+l. Here, when 2≦k+l, B ¹ and B ² and G ¹ and G ² may be the same or different from each other.
E ¹ and E ² each independently represent an alkanediyl group having 1 to 17 carbon atoms, more preferably an alkanediyl group having 4 to 12 carbon atoms. A hydrogen atom contained in the alkanediyl group may be substituted with a halogen atom, and —CH ₂ — contained in the alkanediyl group is —O—, —S—, —SiH ₂ —, —C It may be substituted with (=O)-.
P ¹ and P ² each independently represent a polymerizable group or a hydrogen atom, at least one of which is a polymerizable group.

G ¹ and G ² are each independently preferably a 1,4-phenylenediyl group optionally substituted with at least one substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms. , a 1,4-cyclohexanediyl group optionally substituted with at least one substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms, more preferably 1 substituted with a methyl group ,4-phenylenediyl group, unsubstituted 1,4-phenylenediyl group, or unsubstituted 1,4-trans-cyclohexanediyl group, particularly preferably unsubstituted 1,4-phenylenediyl group, or unsubstituted It is a substituted 1,4-trans-cyclohexanediyl group.
At least one of G ¹ and G ² present in plurality is preferably a divalent alicyclic hydrocarbon group, and at least one of G ¹ and G ² bonded to L ¹ or L ² is more preferably a divalent alicyclic hydrocarbon group.

L ¹ and L ² are each independently preferably a single bond, an alkylene group having 1 to 4 carbon atoms, —O—, —S—, —R ^a1 OR ^a2 —, —R ^a3 COOR ^a4 —, —R ^a5 OCOR ^a6 -, -R ^a7 OC=OOR ^a8 -, -N=N-, -CR ^c =CR ^d -, or -C≡C-. Here, R ^a1 to R ^a8 each independently represent a single bond or an alkylene group having 1 to 4 carbon atoms, and R ^c and R ^d represent an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. L ¹ and L ² are each independently more preferably a single bond, -OR ^a2-1 -, -CH ₂ -, -CH ₂ CH ₂ -, ^{-COOR a4-1} -, or -OCOR ^a6-1 - be. Here, R ^a2-1 , R ^a4-1 and R ^a6-1 each independently represent a single bond, —CH ₂ — or —CH ₂ CH ₂ —. L ¹ and L ² are each independently more preferably a single bond, -O-, -CH ₂ CH ₂ -, -COO-, -COOCH ₂ CH ₂ -, or -OCO-.

B ¹ and B ² are each independently preferably a single bond, an alkylene group having 1 to 4 carbon atoms, —O—, —S—, —R ^a9 OR ^a10 —, —R ^a11 COOR ^a12 —, —R ^a13 OCOR ^a14 -, or -R ^a15 OC= ^{OOR a16} -. Here, R ^a9 to R ^a16 each independently represent a single bond or an alkylene group having 1 to 4 carbon atoms. B ¹ and B ² are each independently more preferably a single bond, —OR ^a10-1 —, —CH ₂ —, —CH ₂ CH ₂ —, ^{—COOR a12-1} —, or —OCOR ^a14-1 — be. Here, R ^a10-1 , R ^a12-1 and R ^a14-1 each independently represent a single bond, —CH ₂ — or —CH ₂ CH ₂ —. B ¹ and B ² are each independently more preferably a single bond, -O-, -CH ₂ CH ₂ -, -COO-, -COOCH ₂ CH ₂ -, -OCO-, or OCOCH ₂ CH ₂ - .

k and l are preferably in the range of 2≦k+l≦6, preferably k+l=4, and more preferably k=2 and l=2 from the viewpoint of manifestation of reverse wavelength dispersion. It is preferable that k=2 and l=2 because of the symmetrical structure.

Polymerizable groups represented by P ¹ or P ² include epoxy group, vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloyloxy group, methacryloyloxy group and oxiranyl group. , and oxetanyl groups. Among them, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxiranyl group and an oxetanyl group are preferred, and an acryloyloxy group is more preferred.

Ar preferably has at least one selected from an optionally substituted aromatic hydrocarbon ring, an optionally substituted aromatic heterocycle, and an electron-withdrawing group. Examples of the aromatic hydrocarbon ring include benzene ring, naphthalene ring, anthracene ring and the like, with benzene ring and naphthalene ring being preferred. Examples of the aromatic heterocyclic ring include furan ring, benzofuran ring, pyrrole ring, indole ring, thiophene ring, benzothiophene ring, pyridine ring, pyrazine ring, pyrimidine ring, triazole ring, triazine ring, pyrroline ring, imidazole ring, and pyrazole ring. , thiazole ring, benzothiazole ring, thienothiazole ring, oxazole ring, benzoxazole ring, and phenanthroline ring. Among them, it preferably has a thiazole ring, a benzothiazole ring, or a benzofuran ring, and more preferably has a benzothiazole group. Moreover, when a nitrogen atom is contained in Ar, the nitrogen atom preferably has a π electron.

In formula (X), the total number Nπ of π electrons contained in the divalent aromatic group represented by Ar is preferably 8 or more, more preferably 10 or more, still more preferably 14 or more, and particularly preferably is 16 or greater. Also, it is preferably 30 or less, more preferably 26 or less, and still more preferably 24 or less.

Examples of aromatic groups represented by Ar include the following groups.

In formulas (Ar-1) to (Ar-23), the * mark represents a connecting portion, and Z ⁰ , Z ¹ and Z ² each independently represent a hydrogen atom, a halogen atom, or an alkyl having 1 to 12 carbon atoms. a cyano group, a nitro group, an alkylsulfinyl group having 1 to 12 carbon atoms, an alkylsulfonyl group having 1 to 12 carbon atoms, a carboxyl group, a fluoroalkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkylthio group having 1 to 12 carbon atoms, an N-alkylamino group having 1 to 12 carbon atoms, an N,N-dialkylamino group having 2 to 12 carbon atoms, an N-alkylsulfamoyl group having 1 to 12 carbon atoms, or carbon represents an N,N-dialkylsulfamoyl group of numbers 2 to 12; Moreover, Z ⁰ , Z ¹ and Z ² may contain a polymerizable group.

Q ¹ and Q ² each independently represent -CR ^2' R ^3' -, -S-, -NH-, -NR ^2' -, -CO- or -O-, and R ^2' and R ^{3 '} each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

J ¹ and J ² each independently represent a carbon atom or a nitrogen atom.

Y ¹ , Y ² and Y ³ each independently represent an optionally substituted aromatic hydrocarbon group or aromatic heterocyclic group.

W ¹ and W ² each independently represent a hydrogen atom, a cyano group, a methyl group or a halogen atom, and m represents an integer of 0-6.

Examples of the aromatic hydrocarbon group for Y ¹ , Y ² and Y ³ include aromatic hydrocarbon groups having 6 to 20 carbon atoms such as phenyl group, naphthyl group, anthryl group, phenanthryl group and biphenyl group. , is preferably a naphthyl group, more preferably a phenyl group. The aromatic heterocyclic group includes a C4-20 group containing at least one heteroatom such as a nitrogen atom, an oxygen atom, a sulfur atom such as a furyl group, a pyrrolyl group, a thienyl group, a pyridinyl group, a thiazolyl group and a benzothiazolyl group. An aromatic heterocyclic group can be mentioned, and a furyl group, a thienyl group, a pyridinyl group, a thiazolyl group, and a benzothiazolyl group are preferable.

Y ¹ , Y ² and Y ³ may each independently be an optionally substituted polycyclic aromatic hydrocarbon group or polycyclic aromatic heterocyclic group. A polycyclic aromatic hydrocarbon group refers to a condensed polycyclic aromatic hydrocarbon group or a group derived from an aromatic ring assembly. A polycyclic aromatic heterocyclic group refers to a condensed polycyclic aromatic heterocyclic group or a group derived from an aromatic ring assembly.

Z ⁰ , Z ¹ and Z ² are each independently preferably a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyano group, a nitro group, an alkoxy group having 1 to 12 carbon atoms, and Z ⁰ is more preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a cyano group, and Z ¹ and Z ² are more preferably a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, or a cyano group. Moreover, Z ⁰ , Z ¹ and Z ² may contain a polymerizable group.

Q ¹ and Q ² are preferably -NH-, -S-, -NR ^2' - and -O-, and R ^2' is preferably a hydrogen atom. Among them, -S-, -O- and -NH- are particularly preferred.

Among formulas (Ar-1) to (Ar-23), formulas (Ar-6) and (Ar-7) are preferable from the viewpoint of molecular stability.

In formulas (Ar-16) to (Ar-23), Y ¹ may form an aromatic heterocyclic group together with the nitrogen atom to which it is attached and Z ⁰ . Examples of the aromatic heterocyclic group include those described above as the aromatic heterocyclic ring that Ar may have, and examples thereof include pyrrole ring, imidazole ring, pyrroline ring, pyridine ring, pyrazine ring, pyrimidine ring, and indole. ring, quinoline ring, isoquinoline ring, purine ring, pyrrolidine ring and the like. This aromatic heterocyclic group may have a substituent. In addition, Y ¹ may be the optionally substituted polycyclic aromatic hydrocarbon group or polycyclic aromatic heterocyclic group described above together with the nitrogen atom and Z ⁰ to which it is attached. Examples include benzofuran ring, benzothiazole ring, benzoxazole ring and the like.

Further, as the polymerizable liquid crystal compound forming the dye-containing layer, for example, a compound containing a group represented by the following formula (Y) (hereinafter sometimes referred to as "polymerizable liquid crystal compound (Y)") is used. good too. The polymerizable liquid crystal compound (Y) generally tends to exhibit positive wavelength dispersion. A polymerizable liquid crystal compound can be used individually or in combination of 2 or more types.

P11-B11-E11-B12-A11-B13- (Y)
[In formula (Y),
P11 represents a polymerizable group.
A11 represents a divalent alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group. The hydrogen atom contained in the divalent alicyclic hydrocarbon group and the divalent aromatic hydrocarbon group is a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group or a nitro group. A hydrogen atom contained in the alkyl group having 1 to 6 carbon atoms and the alkoxy group having 1 to 6 carbon atoms may be substituted with a fluorine atom.
B11 is -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -CO-NR ¹⁶ -, -NR ¹⁶ -CO-, -CO-, - represents CS- or a single bond; R ¹⁶ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
B12 and B13 each independently represent -C≡C-, -CH=CH-, -CH ₂ -CH ₂ -, -O-, -S-, -C(=O)-, -C(=O ) -O-, -O-C(=O)-, -O-C(=O)-O-, -CH=N-, -N=CH-, -N=N-, -C(=O ) -NR ¹⁶ -, -NR ¹⁶ -C(=O)-, -OCH ₂ -, -OCF ₂ -, -CH ₂ O-, -CF ₂ O-, -CH=CH-C(=O)- represents O-, -OC(=O)-CH=CH- or a single bond;
E11 represents an alkanediyl group having 1 to 12 carbon atoms, the hydrogen atom contained in the alkanediyl group may be substituted with an alkoxy group having 1 to 5 carbon atoms, and the hydrogen atom contained in the alkoxy group may be substituted with a halogen atom. -CH ₂ - constituting the alkanediyl group may be replaced with -O- or -CO-. ]

The number of carbon atoms in the aromatic hydrocarbon group and alicyclic hydrocarbon group of A11 is preferably in the range of 3 to 18, more preferably in the range of 5 to 12, particularly 5 or 6. preferable. A11 is preferably a cyclohexane-1,4-diyl group or a 1,4-phenylene group.

E11 is preferably a linear alkanediyl group having 1 to 12 carbon atoms. —CH ₂ — constituting the alkanediyl group may be replaced with —O—.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane -1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group and dodecane-1,12- Linear alkanediyl groups having 1 to 12 carbon atoms such as diyl groups; -CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -O- CH ₂ -CH ₂ - and -CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -O-CH ₂ -CH ₂ - and the like.
B11 is preferably -O-, -S-, -CO-O- or -O-CO-, and more preferably -CO-O-.
B12 and B13 each independently represent -O-, -S-, -C(=O)-, -C(=O)-O-, -OC(=O)-, -OC (=O)-O- is preferred, and -O- or -OC(=O)-O- is more preferred.

［式（Ｐ－１１）～（Ｐ－１５）中、
Ｒ^１７～Ｒ^２１はそれぞれ独立に、炭素数１～６のアルキル基又は水素原子を表す。］ As the polymerizable group represented by P11, a radically polymerizable group or a cationically polymerizable group is preferable in terms of high polymerization reactivity, particularly photopolymerization reactivity, and handling is easy, and the production of the liquid crystal compound itself is also easy. Therefore, the polymerizable group is preferably a group represented by the following formulas (P-11) to (P-15).

[In the formulas (P-11) to (P-15),
R ¹⁷ to R ²¹ each independently represent an alkyl group having 1 to 6 carbon atoms or a hydrogen atom. ]

Specific examples of the groups represented by formulas (P-11) to (P-15) include groups represented by the following formulas (P-16) to (P-20).

P11 is preferably a group represented by formulas (P-14) to (P-20), more preferably a vinyl group, a p-stilbene group, an epoxy group or an oxetanyl group.
More preferably, the group represented by P11-B11- is an acryloyloxy group or a methacryloyloxy group.

Examples of the polymerizable liquid crystal compound (Y) include compounds represented by formula (I), formula (II), formula (III), formula (IV), formula (V), or formula (VI).
P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-B16-E12-B17-P12 (I)
P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-F11 (II)
P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-E12-B17-P12 (III)
P11-B11-E11-B12-A11-B13-A12-B14-A13-F11 (IV)
P11-B11-E11-B12-A11-B13-A12-B14-E12-B17-P12 (V)
P11-B11-E11-B12-A11-B13-A12-F11 (VI)
[In the formulas (I) to (VI),
A12 to A14 are each independently synonymous with A11, B14 to B16 are each independently synonymous with B12, B17 is synonymous with B11, and E12 is synonymous with E11.
F11 is a hydrogen atom, an alkyl group having 1 to 13 carbon atoms, an alkoxy group having 1 to 13 carbon atoms, a cyano group, a nitro group, a trifluoromethyl group, a dimethylamino group, a hydroxy group, a methylol group, a formyl group, a sulfo group; (—SO ₃ H), a carboxy group, an alkoxycarbonyl group having 1 to 10 carbon atoms or a halogen atom, and —CH ₂ — constituting the alkyl group and alkoxy group may be replaced with —O— good. ]

Specific examples of the polymerizable liquid crystal compound (Y) are described in "3.8.6 Network (completely crosslinked type)" in Liquid Crystal Handbook (Liquid Crystal Handbook Editing Committee, published by Maruzen Co., Ltd. on October 30, 2000). , Compounds having a polymerizable group among the compounds described in "6.5.1 Liquid crystal material b. Polymerizable nematic liquid crystal material", JP 2010-31223, JP 2010-270108, JP Polymerizable liquid crystals described in JP-A-2011-6360 and JP-A-2011-207765 can be mentioned.

Specific examples of the polymerizable liquid crystal compound (Y) include the following formulas (I-1) to (I-4), formulas (II-1) to (II-4), formulas (III-1) to formula (III-26), formulas (IV-1) to (IV-26), formulas (V-1) to (V-2) and formulas (VI-1) to (VI-6) compound. In the following formula, k1 and k2 each independently represent an integer of 2-12. These polymerizable liquid crystal compounds (Y) are preferable in terms of ease of synthesis or availability.

By using a polymerizable liquid crystal compound exhibiting smectic liquid crystallinity, a dye-containing layer having a high degree of orientational order can be formed. is small and the value of AxC (z=60)/AxC is large. When a polymerizable liquid crystal compound exhibiting smectic liquid crystallinity is used as the polymerizable liquid crystal compound forming the dye-containing layer, the polymerizable liquid crystal compound has a high-order smectic phase (high-order smectic liquid crystal state). Here, the higher order smectic phase includes smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic I phase, smectic J phase, smectic K phase and smectic L phase. Among these, smectic B phase, smectic F phase and smectic I phase are more preferable. Thermotropic liquid crystals or lyotropic liquid crystals may be used as liquid crystals, but thermotropic liquid crystals are preferred because they allow precise film thickness control. Further, the polymerizable liquid crystal compound exhibiting smectic liquid crystallinity may be a monomer, but may be an oligomer or polymer in which a polymerizable group is polymerized.

The polymerizable liquid crystal compound exhibiting smectic liquid crystallinity is a liquid crystal compound having at least one polymerizable group, and from the viewpoint of improving the heat resistance of the dye-containing layer, it is preferred to be a liquid crystal compound having two or more polymerizable groups. preferable. Examples of the polymerizable group include (meth)acryloyloxy, vinyl, vinyloxy, 1-chlorovinyl, isopropenyl, 4-vinylphenyl, oxiranyl, and oxetanyl groups. (Meth)acryloyloxy groups are preferred because they facilitate the process, improve the heat resistance of the dye-containing layer, and facilitate adjustment of the adhesion between the dye-containing layer and the substrate. As used herein, (meth)acryloyl refers to acryloyl or methacryloyl.

Polymerizable liquid crystal compounds exhibiting smectic liquid crystallinity include, for example, compounds represented by the following formula (Z) (hereinafter sometimes referred to as “polymerizable liquid crystal compound (Z)”).
U ^1z -V ^1z -W ^1z -(X ^1z -Y ^1z -) _nz -X ^2z -W ^2z -V ^2z -U ^2z (Z)
[In formula (Z),
X ^1z and X ^2z each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group, wherein the divalent aromatic group or divalent alicyclic hydrocarbon A hydrogen atom contained in the group may be substituted with a halogen atom, an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group or a nitro group. A carbon atom constituting the divalent aromatic group or divalent alicyclic hydrocarbon group may be substituted with an oxygen atom, a sulfur atom, or a nitrogen atom. However, at least one of X ^1z and X ^2z is an optionally substituted 1,4-phenylene group or an optionally substituted cyclohexane-1,4-diyl group.
Y ^1z is a single bond or a divalent linking group.
nz is 1 to 3, and when nz is 2 or more, a plurality of X ^1z may be the same or different. X ^2z may be the same as or different from any or all of a plurality of X ^1z . Also, when nz is 2 or more, the plurality of Y ^1z may be the same or different. From the viewpoint of liquid crystallinity, nz is preferably 2 or more.
U ^1z represents a hydrogen atom or a (meth)acryloyloxy group.
U ^2z represents a polymerizable group.
W ^1z and W ^2z are each independently a single bond or a divalent linking group.
V ^1z and V ^2z each independently represent an optionally substituted alkanediyl group having 1 to 20 carbon atoms, and —CH ₂ — constituting the alkanediyl group is —O—, -CO-, -S- or -NH- may be substituted. ]

In the polymerizable liquid crystal compound (Z), X ^1z and X ^2z are each independently preferably a 1,4-phenylene group optionally having a substituent, or a 1,4-phenylene group optionally having a substituent, or a cyclohexane-1,4-diyl group, wherein at least one of X ^1z and X ^2z is an optionally substituted 1,4-phenylene group, or a substituted cyclohexane-1,4-diyl group, preferably trans-cyclohexane-1,4-diyl group. Optionally substituted 1,4-phenylene group or optionally substituted cyclohexane-1,4-diyl group may have a methyl group, ethyl and alkyl groups having 1 to 4 carbon atoms such as butyl group, cyano group and halogen atoms such as chlorine atom and fluorine atom. It is preferably unsubstituted.

Further, the polymerizable liquid crystal compound (Z) has the formula (Z1) in the formula (Z):
-(X ^1z -Y ^1z -) _n -X ^2z - (Z1)
[In Formula (Z1), X ^1z , Y ^1z , X ^2z and nz each have the same meaning as above. ] (hereinafter may be referred to as “partial structure (Z1)”) has an asymmetric structure, because it facilitates smectic liquid crystallinity.
As the polymerizable liquid crystal compound (Z) in which the partial structure (Z1) is an asymmetric structure, for example, there is a polymerizable liquid crystal compound (Z) in which nz is 1 and one ^X1z and one ^X2z are different structures. mentioned. Also, a compound in which nz is 2, two Y ^1z have the same structure, two X ^1z have the same structure, and one X ^2z has a different structure from these two X ^1z Polymerizable liquid crystal compound (Z), X ^1z bonded to W ^1z of two X ^1z has a different structure from the other X ^1z and X ^2z , and the other X ^1z and X ^2z have the same structure A polymerizable liquid crystal compound (Z) is also included. Furthermore, a compound in which nz is 3, three Y ^1z have the same structure, and any one of the three X ^1z and one X ^2z has a different structure from all the other three. liquid crystal compound (Z).

Y ^1z is -CH ₂ CH ₂ -, -CH ₂ O-, -CH ₂ CH ₂ O-, -COO-, -OCOO-, a single bond, -N=N-, -CR ^az =CR ^bz -, -C≡C-, -CR ^az =N- or -CO-NR ^az - are preferred. R ^az and R ^bz each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Y ^1z is more preferably -CH ₂ CH ₂ -, -COO- or a single bond, and when a plurality of Y ^1z are present, Y ^1z bonded to X ^2z is -CH ₂ CH ₂ - or - CH ₂ O— is more preferred. When both X ^1z and X ^2z have the same structure, it is preferable that there are two or more Y ^1z having different bonding schemes. When there are a plurality of Y ^1z having different bonding schemes, an asymmetric structure is formed, and smectic liquid crystallinity tends to occur.

U ^2z is a polymerizable group as described above. U ^1z is a hydrogen atom or a polymerizable group. The polymerizable group is preferably a (meth)acryloyloxy group because it is easy to manufacture, the heat resistance of the dye-containing layer can be easily improved, and the adhesion between the dye-containing layer and the substrate can be easily adjusted. preferable. The polymerizable group may be in a polymerized state or in an unpolymerized state, preferably in an unpolymerized state.

The alkanediyl groups represented by V ^1z and V ^2z include methylene, ethylene, propane-1,3-diyl, butane-1,3-diyl, butane-1,4-diyl, pentane- 1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, decane-1,10-diyl group, tetradecane-1,14-diyl group and icosane-1,20-diyl group. V ^1z and V ^2z are preferably alkanediyl groups having 2 to 12 carbon atoms, more preferably alkanediyl groups having 6 to 12 carbon atoms.

Examples of substituents optionally possessed by the alkanediyl group include a cyano group and a halogen atom. The alkanediyl group is preferably unsubstituted, and is an unsubstituted linear alkanediyl group is more preferred.

W ^1z and W ^2z are each independently preferably a single bond, -O-, -S-, -COO- or -OCOO-, more preferably a single bond or -O-.

The polymerizable liquid crystal compound (Z) preferably has an asymmetric molecular structure in its molecular structure, and specifically has a partial structure represented by the following formulas (Aa) to (Ai). A polymerizable liquid crystal compound is more preferable. It is more preferable to have a partial structure represented by formula (Aa), formula (Ab), or formula (Ac) from the viewpoint of easily exhibiting high-order smectic liquid crystallinity. In formulas (Aa) to (Ai), * represents a bond (single bond).

Specific examples of the polymerizable liquid crystal compound (Z) include compounds represented by formulas (A-1) to (A-25). When the polymerizable liquid crystal compound (Z) has a cyclohexane-1,4-diyl group, the cyclohexane-1,4-diyl group is preferably a trans form.

Among these, formula (A-2), formula (A-3), formula (A-4), formula (A-5), formula (A-6), formula (A-7), formula (A- 8), at least one selected from the group consisting of compounds represented by formula (A-13), formula (A-14), formula (A-15), formula (A-16) and formula (A-17) Seeds are preferred. As the polymerizable liquid crystal compound (Z), one type may be used alone, or two or more types may be used in combination.

The polymerizable liquid crystal compound (Z) is described, for example, in Lub et al., Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996), or a known method described in Japanese Patent No. 4,719,156.

The polymerizable liquid crystal compound forming the dye-containing layer is preferably a polymerizable liquid crystal compound having a maximum absorption wavelength in the range of 300 to 400 nm. When the polymerizable liquid crystal composition forming the dye-containing layer contains a photopolymerization initiator, the polymerization reaction and gelation of the polymerizable liquid crystal compound may proceed during long-term storage. However, if the maximum absorption wavelength of the polymerizable liquid crystal compound is 300 to 400 nm, even if it is exposed to ultraviolet light during storage, the generation of reactive species from the photopolymerization initiator and the production of the polymerizable liquid crystal compound by the reactive species. It can effectively suppress the progress of the polymerization reaction and gelation. Therefore, it is advantageous in terms of the long-term stability of the polymerizable liquid crystal composition, and the orientation and thickness uniformity of the obtained dye-containing layer can be improved. The maximum absorption wavelength of the polymerizable liquid crystal compound can be measured in a solvent using an ultraviolet-visible spectrophotometer. The solvent is a solvent capable of dissolving the polymerizable liquid crystal compound, and examples thereof include chloroform.

The content of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition forming the dye-containing layer is, for example, 70 to 99.5 parts by mass with respect to 100 parts by mass of the solid content of the polymerizable liquid crystal composition, preferably It is 80 to 99 parts by mass, more preferably 85 to 98 parts by mass, still more preferably 90 to 95 parts by mass. When the content of the polymerizable liquid crystal compound is within the above range, it is advantageous from the viewpoint of the orientation of the resulting dye-containing layer. In the present specification, the solid content of the polymerizable liquid crystal composition means all components excluding volatile components such as organic solvents from the polymerizable liquid crystal composition.

The polymerizable liquid crystal composition used for forming the dye-containing layer contains, in addition to the polymerizable liquid crystal compound and the present dichroic dye, additives such as a solvent, a photopolymerization initiator, a leveling agent, an antioxidant, and a photosensitizer. may further include Each of these components may be used alone or in combination of two or more.

Since the polymerizable liquid crystal composition for forming the dye-containing layer is usually applied to a substrate or the like in a state of being dissolved in a solvent, it preferably contains a solvent. As the solvent, a solvent capable of dissolving the polymerizable liquid crystal compound is preferable, and a solvent inert to the polymerization reaction of the polymerizable liquid crystal compound is preferable. Examples of solvents include water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy-2-propanol, 2-butoxyethanol, and propylene glycol monomethyl ether. Alcohol solvents; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate, and ethyl lactate; acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone solvents such as ketones; aliphatic hydrocarbon solvents such as pentane, hexane, and heptane; alicyclic hydrocarbon solvents such as ethylcyclohexane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; Ether solvents such as dimethoxyethane; Chlorine-containing solvents such as chloroform and chlorobenzene; Amide solvents such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone A solvent etc. are mentioned. These solvents can be used alone or in combination of two or more. Among these, alcohol solvents, ester solvents, ketone solvents, chlorine-containing solvents, amide solvents, and aromatic hydrocarbon solvents are preferred.

The content of the solvent in the polymerizable liquid crystal composition is preferably 50 to 98 parts by weight, more preferably 70 to 95 parts by weight, per 100 parts by weight of the polymerizable liquid crystal composition. Therefore, the solid content in 100 parts by mass of the polymerizable liquid crystal composition is preferably 2 to 50 parts by mass. When the solid content is 50 parts by mass or less, the viscosity of the polymerizable liquid crystal composition is low, so that the thickness of the layer becomes substantially uniform, and unevenness tends to be less likely to occur. The above solid content can be appropriately determined in consideration of the thickness of the dye-containing layer to be produced.

The polymerization initiator is a compound capable of initiating a polymerization reaction such as a polymerizable liquid crystal compound by generating reactive species with the contribution of heat or light. Examples of reactive species include radicals or active species such as cations and anions. Among them, a photopolymerization initiator that generates radicals by light irradiation is preferable from the viewpoint that reaction control is easy.

Examples of photopolymerization initiators include benzoin compounds, benzophenone compounds, benzyl ketal compounds, α-hydroxyketone compounds, α-aminoketone compounds, oxime compounds, triazine compounds, iodonium salts and sulfonium salts. Specifically, Irgacure (registered trademark) 907, Irgacure 184, Irgacure 651, Irgacure 819, Irgacure 250, Irgacure 369, Irgacure 379, Irgacure 127, Irgacure 2959, Irgacure 754, Irgacure 379EG (above, BASF Japan Corporation ), Seikuol BZ, Seikuol Z, Seikuol BEE (manufactured by Seiko Chemical Co., Ltd.), Kayacure BP100 (manufactured by Nippon Kayaku Co., Ltd.), Kayacure UVI-6992 (manufactured by Dow), Adeka Optomer SP- 152, Adeka Optomer SP-170, Adeka Optomer N-1717, Adeka Optomer N-1919, Adeka Arkles NCI-831, Adeka Arkles NCI-930 (manufactured by ADEKA Co., Ltd.), TAZ-A, TAZ -PP (manufactured by Nihon SiberHegner Co., Ltd.) and TAZ-104 (manufactured by Sanwa Chemical Co., Ltd.).

Since the photopolymerization initiator can fully utilize the energy emitted from the light source and is excellent in productivity, it is preferable that the maximum absorption wavelength is 300 nm to 400 nm, more preferably 300 nm to 380 nm. Polymerization initiators and oxime photopolymerization initiators are preferred.

α-Acetophenone compounds include 2-methyl-2-morpholino-1-(4-methylsulfanylphenyl)propan-1-one, 2-dimethylamino-1-(4-morpholinophenyl)-2-benzylbutane-1 -one and 2-dimethylamino-1-(4-morpholinophenyl)-2-(4-methylphenylmethyl)butan-1-one and the like, more preferably 2-methyl-2-morpholino-1-( 4-methylsulfanylphenyl)propan-1-one and 2-dimethylamino-1-(4-morpholinophenyl)-2-benzylbutan-1-one. Commercially available α-acetophenone compounds include Irgacure 369, 379EG, and 907 (manufactured by BASF Japan Ltd.) and Seikuol BEE (manufactured by Seiko Kagaku Co., Ltd.).

Oxime-based photopolymerization initiators generate radicals such as phenyl radicals and methyl radicals when irradiated with light. Polymerization of the polymerizable liquid crystal compound favorably proceeds by these radicals, and among them, an oxime-based photopolymerization initiator that generates methyl radicals is preferable because of its high initiation efficiency of the polymerization reaction. Moreover, from the viewpoint of allowing the polymerization reaction to proceed more efficiently, it is preferable to use a photopolymerization initiator capable of efficiently utilizing ultraviolet rays having a wavelength of 350 nm or more. As a photopolymerization initiator capable of efficiently utilizing ultraviolet light having a wavelength of 350 nm or more, a triazine compound or a carbazole compound containing an oxime structure is preferable, and a carbazole compound containing an oxime ester structure is more preferable from the viewpoint of sensitivity. Carbazole compounds containing an oxime structure include 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2-methyl benzoyl)-9H-carbazol-3-yl]-1-(O-acetyloxime) and the like. Commercially available oxime ester photopolymerization initiators include Irgacure OXE-01, Irgacure OXE-02, Irgacure OXE-03 (manufactured by BASF Japan Ltd.), Adeka Optomer N-1919, and Adeka Arcles NCI-831. (above, manufactured by ADEKA Corporation) and the like.

The content of the photopolymerization initiator is usually 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, and more preferably 1 to 15 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. is. Within the above range, the reaction of the polymerizable group proceeds sufficiently and the alignment of the polymerizable liquid crystal compound is less likely to be disturbed.

A leveling agent is an additive that has the function of adjusting the fluidity of the polymerizable liquid crystal composition and making the coating film obtained by coating the composition more flat. A fluoroalkyl-based leveling agent can be used. Commercially available products may be used as the leveling agent. Specifically, DC3PA, SH7PA, DC11PA, SH28PA, SH29PA, SH30PA, ST80PA, ST86PA, SH8400, SH8700, FZ2123 (all manufactured by Dow Corning Toray Co., Ltd.). , KP321, KP323, KP324, KP326, KP340, KP341, X22-161A, KF6001 (all manufactured by Shin-Etsu Chemical Co., Ltd.), TSF400, TSF401, TSF410, TSF4300, TSF4440, TSF4445, TSF-4446, TSF446, TSF444 (all manufactured by Momentive Performance Materials Japan LLC), fluorinert (registered trademark) FC-72, FC-40, FC-43, FC-3283 (all manufactured by Sumitomo 3M Co., Ltd.) ), Megafac (registered trademark) R-08, R-30, R-90, F-410, F-411, F-443, F-445, F-470, F- 477, F-479, F-482, F-483, F-556 (all manufactured by DIC Corporation), F-top (trade name) EF301, EF303, EF351, EF352 ( All of the above are manufactured by Mitsubishi Materials Electronics Chemical Co., Ltd.), Surflon (registered trademark) S-381, S-382, S-383, S-393, SC-101, SC-105, KH-40 , SA-100 (all manufactured by AGC Seimi Chemical Co., Ltd.), trade names E1830, E5844 (manufactured by Daikin Fine Chemicals Laboratory Co., Ltd.), BM-1000, BM-1100, BYK-352, BYK-353 and BYK-361N (both trade names: manufactured by BM Chemie) and the like. A leveling agent can be used individually or in combination of 2 or more types.

The content of the leveling agent is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound. When the content of the leveling agent is within the above range, it is preferable because the polymerizable liquid crystal compound can be easily oriented and the resulting dye-containing layer tends to be smoother.

By adding an antioxidant, the polymerization reaction of the polymerizable liquid crystal compound can be controlled. The antioxidant may be a primary antioxidant selected from phenol antioxidants, amine antioxidants, quinone antioxidants, nitroso antioxidants, phosphorus antioxidants and sulfur It may be a secondary antioxidant selected from system antioxidants. In order to polymerize the polymerizable liquid crystal compound without disturbing the alignment of the polymerizable liquid crystal compound, the content of the antioxidant is usually 0.01 to 10 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. Yes, preferably 0.1 to 5 parts by mass, more preferably 0.1 to 3 parts by mass. An antioxidant can be used individually or in combination of 2 or more types.

A photopolymerization initiator can be highly sensitive by using a photosensitizer. Examples of photosensitizers include xanthones such as xanthone and thioxanthone; anthracenes having substituents such as anthracene and alkyl ether; phenothiazine; and rubrene. A photosensitizer can be used individually or in combination of 2 or more types. The content of the photosensitizer is usually 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. 3 parts by mass.

The polymerizable liquid crystal composition is prepared by stirring a polymerizable liquid crystal compound and the present dichroic dye, and components other than the polymerizable liquid proof compound and the present dichroic dye, such as a solvent and a photopolymerization initiator, at a predetermined temperature. can be obtained by

(Method for producing dye-containing layer)
When the dye-containing layer contains a polymerizable liquid crystal compound, the dye-containing layer contains, for example,
forming a coating film of a polymerizable liquid crystal composition for forming a dye-containing layer;
A step of drying the coating film to form a dry coating film, and
It can be produced by a method including a step of irradiating a dry coating film with an active energy ray to form a dye-containing layer.

The coating film of the polymerizable liquid crystal composition can be formed, for example, by applying the polymerizable liquid crystal composition for forming the dye-containing layer onto a substrate, an alignment film, a polarizing layer, or the like.

Examples of the substrate include glass substrates and film substrates, and resin film substrates are preferable from the viewpoint of workability. Examples of resins constituting the film substrate include polyolefins such as polyethylene, polypropylene, and norbornene-based polymers; cyclic olefin-based resins; polyvinyl alcohol; polyethylene terephthalate; Cellulose esters such as diacetyl cellulose and cellulose acetate propionate; plastics such as polyethylene naphthalate; polycarbonates; polysulfones; polyethersulfones; polyetherketones; Such a resin can be formed into a film substrate by known means such as a solvent casting method and a melt extrusion method. A protective layer made of an acrylic resin, a methacrylic resin, an epoxy resin, an oxetane resin, a urethane resin, a melamine resin, or the like may be formed on the surface of the film substrate. You may use it as a base material. The surface of the film substrate may be subjected to a release treatment such as silicone treatment, a corona treatment, a surface treatment such as plasma treatment, etc., and the film substrate and the layer formed by the surface treatment are used as the substrate. may Examples of the protective layer include a hard coat layer (the above-described third hard coat layer) and the like. Examples of the hard coat layer include those described in the hard coat layer (first hard coat layer) for protecting the surface of the dye-containing layer described later. When the substrate film is provided with a protective layer or surface-treated, it is preferable that an alignment film and/or a dye-containing layer is laminated on the protective layer side or the surface-treated side.

A commercially available product may be used as the substrate. Commercially available cellulose ester substrates include, for example, cellulose ester substrates manufactured by Fuji Photo Film Co., Ltd. such as Fujitac Film; and cellulose ester base materials. Examples of commercially available cyclic olefin resins include cyclic olefin resins manufactured by Ticona (Germany) such as "Topas (registered trademark)"; cyclic olefin resins manufactured by JSR Corporation such as "Arton (registered trademark)"; Resin; Cyclic olefin resin manufactured by Nippon Zeon Co., Ltd. such as "ZEONOR (registered trademark)" and "ZEONEX (registered trademark)"; Mitsui Chemicals such as "APEL" (registered trademark) Cyclic olefin-based resins manufactured by K.K. A commercially available cyclic olefin resin base material can also be used. Examples of commercially available cyclic olefin resin substrates include cyclic olefin resin substrates manufactured by Sekisui Chemical Co., Ltd. such as "Escina (registered trademark)" and "SCA40 (registered trademark)"; Optes Co., Ltd. cyclic olefin resin base material such as "; JSR Co., Ltd. cyclic olefin resin base material such as "Arton Film (registered trademark)".

The thickness of the substrate is usually 5 to 300 μm, preferably 10 to 150 μm, from the viewpoints of thinning of the optical layered body, ease of peeling of the substrate, handleability of the substrate, and the like.

Examples of methods for applying the polymerizable liquid crystal composition to a substrate or the like include coating methods such as spin coating, extrusion, gravure coating, die coating, bar coating, and applicator methods, and printing methods such as flexography. and other known methods.

Then, the solvent is removed by drying or the like to form a dry coating film. Examples of the drying method include natural drying, ventilation drying, heat drying, and reduced pressure drying. At this time, by heating the coating film obtained from the polymerizable liquid crystal composition, the solvent can be removed from the coating film by drying, and the polymerizable liquid crystal compound can be oriented in the direction perpendicular to the plane of the coating film. The heating temperature of the coating film can be appropriately determined in consideration of the polymerizable liquid crystal compound to be used and the material of the base material forming the coating film. The temperature must be equal to or higher than the phase transition temperature. In order to bring the polymerizable liquid crystal compound into a vertically aligned state while removing the solvent contained in the polymerizable liquid crystal composition, for example, the liquid crystal phase transition temperature (smectic phase transition temperature) of the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition or nematic phase transition temperature).

The liquid crystal phase transition temperature can be measured using, for example, a polarizing microscope equipped with a temperature control stage, a differential scanning calorimeter (DSC), a thermogravimetric differential thermal analyzer (TG-DTA), or the like. Further, when two or more kinds of polymerizable liquid crystal compounds are used in combination, the phase transition temperature is obtained by polymerization in which all the polymerizable liquid crystal compounds constituting the polymerizable liquid crystal composition are mixed in the same ratio as the composition in the polymerizable liquid crystal composition. It means a temperature measured using a mixture of polymerizable liquid crystal compounds in the same manner as in the case of using one type of polymerizable liquid crystal compound. It is generally known that the liquid crystal phase transition temperature of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition may be lower than the liquid crystal phase transition temperature of the polymerizable liquid crystal compound itself.

The heating time can be appropriately determined according to the heating temperature, the type of polymerizable liquid crystal compound used, the type of solvent, its boiling point and its amount, etc., but it is usually 15 seconds to 10 minutes, preferably 0.5 to 10 minutes. Five minutes.

The removal of the solvent from the coating film may be carried out simultaneously with the heating of the polymerizable liquid crystal compound to the liquid crystal phase transition temperature or higher, or may be carried out separately. Before heating to the liquid crystal phase transition temperature or higher of the polymerizable liquid crystal compound, the solvent in the coating film is moderately added under conditions in which the polymerizable liquid crystal compound contained in the coating film obtained from the polymerizable liquid crystal composition is not polymerized. A pre-drying step may be provided for removal. Examples of the drying method in the preliminary drying step include a natural drying method, a ventilation drying method, a heat drying method, a reduced pressure drying method, and the like. can be determined as appropriate according to the type, boiling point and amount thereof.

Next, in the obtained dried coating film, the dye-containing layer is formed by polymerizing the polymerizable liquid crystal compound while maintaining the vertically aligned state of the polymerizable liquid crystal compound. Examples of the polymerization method include a thermal polymerization method and a photopolymerization method, and the photopolymerization method is preferable from the viewpoint of easy control of the polymerization reaction. In photopolymerization, the light irradiated to the dry coating film includes the type of photopolymerization initiator contained in the dry coating film, the type of polymerizable liquid crystal compound (especially the type of polymerizable group possessed by the polymerizable liquid crystal compound). and is appropriately selected according to its amount. Specific examples thereof include one or more types of light selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays, and γ-rays, and active electron beams. Among them, ultraviolet light is preferable in that it is easy to control the progress of the polymerization reaction and that a widely used photopolymerization apparatus in the field can be used. It is preferable to select the types of the polymerizable liquid crystal compound and the photopolymerization initiator contained in the polymerizable liquid crystal composition. The polymerization temperature can also be controlled by light irradiation while cooling the dry coating film with an appropriate cooling means at the time of polymerization. By adopting such a cooling means and polymerizing the polymerizable liquid crystal compound at a lower temperature, the dye-containing layer can be properly formed even if the base material has relatively low heat resistance. It is also possible to accelerate the polymerization reaction by raising the polymerization temperature within a range in which problems caused by heat during light irradiation (such as deformation of the base material due to heat) do not occur. A patterned dye-containing layer can also be obtained by performing masking, development, or the like during photopolymerization.

Examples of light sources for active energy rays include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, halogen lamps, carbon arc lamps, tungsten lamps, gallium lamps, excimer lasers, and a wavelength range of 380. LED light sources, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, etc., that emit light of up to 440 nm can be used.

The UV irradiation intensity is usually 10 to 3,000 mW/cm ² . The ultraviolet irradiation intensity is preferably in the wavelength range effective for activation of the photopolymerization initiator. The light irradiation time is usually 0.1 seconds to 10 minutes, preferably 0.1 seconds to 5 minutes, more preferably 0.1 seconds to 3 minutes, still more preferably 0.1 seconds to 1 minute. be. When irradiated once or multiple times with such an ultraviolet irradiation intensity, the integrated light quantity is 10 to 3,000 mJ/cm ² , preferably 50 to 2,000 mJ/cm ² , more preferably 100 to 1,000 mJ/cm. ² .

A coating film of the polymerizable liquid crystal composition may be formed on the alignment film. The alignment film has an alignment regulating force that aligns the polymerizable liquid crystal compound in a desired direction. The alignment film includes a horizontal alignment film that has an alignment control force to align the polymerizable liquid crystal compound in the horizontal direction, and a vertical alignment film that has an alignment control force to align the polymerizable liquid crystal compound in the vertical direction. The alignment film used for forming the layers is a vertical alignment film. The alignment regulation force can be arbitrarily adjusted by the type of alignment film, surface condition, rubbing conditions, etc., and when the alignment film is formed from a photo-orientable polymer, it can be arbitrarily adjusted by polarized irradiation conditions, etc. It is possible to

The alignment film preferably has solvent resistance so that it does not dissolve when the polymerizable liquid crystal composition is applied or the like, and also has heat resistance during heat treatment for removing the solvent and for aligning the polymerizable liquid crystal compound, which will be described later. Examples of the alignment film include an alignment film containing an alignment polymer, a photo-alignment film, a groove alignment film having an uneven pattern or a plurality of grooves on the surface, and a stretched film stretched in the alignment direction. A photo-alignment film is preferable from the viewpoint of quality.

Examples of the oriented polymer include polyamides and gelatins having an amide bond in the molecule, polyimide having an imide bond in the molecule and its hydrolysates such as polyamic acid, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, poly Oxazole, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid and polyacrylic acid esters. Among them, polyvinyl alcohol is preferred. Orientation polymer can be used individually or in combination of 2 or more types.

An oriented film containing an oriented polymer is usually prepared by applying a composition in which an oriented polymer is dissolved in a solvent (hereinafter sometimes referred to as an "oriented polymer composition") to a substrate and removing the solvent, or , is obtained by applying an oriented polymer composition to a substrate, removing the solvent, and rubbing (rubbing method). Examples of the solvent include the solvents exemplified above as solvents that can be used in the polymerizable liquid crystal composition.

The concentration of the oriented polymer in the oriented polymer composition may be within a range in which the oriented polymer material can be completely dissolved in the solvent. 0.1 to 10% is more preferable.

A commercially available alignment film material may be used as it is as the alignment polymer composition. Commercially available alignment film materials include Sanever (registered trademark, manufactured by Nissan Chemical Industries, Ltd.) and Optomer (registered trademark, manufactured by JSR Corporation).

Examples of the method for applying the oriented polymer composition to the substrate include the same methods as those exemplified as the method for applying the polymerizable liquid crystal composition to the substrate.

Methods for removing the solvent contained in the oriented polymer composition include natural drying, ventilation drying, heat drying, and vacuum drying.

As a method for imparting an alignment regulating force by a rubbing method, a rubbing cloth is wound around a rotating rubbing roll, and an orienting polymer composition is applied to the substrate and then annealed to form an orientation polymer composition on the substrate surface. A method of contacting a film of an oriented polymer can be mentioned. A plurality of regions (patterns) with different alignment directions can be formed in the alignment film by masking during the rubbing process.

A photo-alignment film is usually formed by coating a substrate with a composition containing a polymer or monomer having a photoreactive group and a solvent (hereinafter sometimes referred to as a "composition for forming a photo-alignment film"), and removing the solvent. It can be obtained by irradiating polarized light (preferably polarized UV) after removal. The photo-alignment film is also advantageous in that the direction of the alignment regulating force can be arbitrarily controlled by selecting the polarization direction of the irradiated polarized light.

A photoreactive group refers to a group that exhibits liquid crystal alignment ability upon irradiation with light. Specific examples include groups involved in photoreactions that cause liquid crystal alignment ability such as orientation induction of molecules caused by light irradiation or isomerization reactions, dimerization reactions, photocrosslinking reactions, photodecomposition reactions, and the like. Among them, a group involved in a dimerization reaction or a photocrosslinking reaction is preferable from the viewpoint of excellent orientation. As the photoreactive group, a group having an unsaturated bond, particularly a double bond is preferable, and a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond (C=N bond), a nitrogen-nitrogen double bond Groups having at least one selected from the group consisting of a heavy bond (N=N bond) and a carbon-oxygen double bond (C=O bond) are particularly preferred.

Photoreactive groups having a C=C bond include vinyl groups, polyene groups, stilbene groups, stilbazole groups, stilbazolium groups, chalcone groups and cinnamoyl groups. Photoreactive groups having a C═N bond include groups having structures such as aromatic Schiff bases and aromatic hydrazones. The photoreactive group having an N=N bond includes an azobenzene group, an azonaphthalene group, an aromatic heterocyclic azo group, a bisazo group, a formazan group, and a group having an azoxybenzene structure. A benzophenone group, a coumarin group, an anthraquinone group, a maleimide group, and the like can be mentioned as the photoreactive group having a C═O bond. These groups may have substituents such as alkyl groups, alkoxy groups, aryl groups, allyloxy groups, cyano groups, alkoxycarbonyl groups, hydroxyl groups, sulfonic acid groups, and halogenated alkyl groups.

Among them, a photoreactive group that participates in a photodimerization reaction is preferable, the amount of polarized light irradiation required for photoalignment is relatively small, and a photoalignment film having excellent thermal stability and stability over time can be easily obtained. Cinnamoyl and chalcone groups are preferred. As the polymer having a photoreactive group, a polymer having a cinnamoyl group having a cinnamic acid structure at the end of the polymer side chain is particularly preferred.

A photo-alignment inducing layer can be formed on a substrate by applying the composition for forming a photo-alignment film onto the substrate. Examples of the solvent contained in the composition include the solvents exemplified above as solvents that can be used in the polymerizable liquid crystal composition, and can be appropriately selected according to the solubility of the polymer or monomer having a photoreactive group. .

The content of the polymer or monomer having a photoreactive group in the composition for forming a photo-alignment film can be appropriately adjusted depending on the type of polymer or monomer and the thickness of the desired photo-alignment film. It is preferably at least 0.2% by mass, more preferably in the range of 0.3 to 10% by mass. The composition for forming a photo-alignment film may contain a polymeric material such as polyvinyl alcohol or polyimide, or a photosensitizer, as long as the properties of the photo-alignment film are not significantly impaired.

The method for applying the photo-alignment film-forming composition to the substrate includes the same method as the method for applying the orienting polymer composition to the substrate. Examples of the method for removing the solvent from the coated composition for forming a photo-alignment film include natural drying, ventilation drying, heat drying, and reduced pressure drying.

In order to irradiate polarized light, the composition for forming a photo-alignment film coated on the substrate may be directly irradiated with polarized UV light after the solvent has been removed. A format in which light is transmitted and irradiated may be used. Moreover, it is particularly preferable that the polarized light is substantially parallel light. The wavelength of the polarized light to be irradiated is preferably in a wavelength range in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb the light energy. Specifically, UV (ultraviolet rays) with a wavelength in the range of 250 to 400 nm is particularly preferred. Light sources used for the polarized irradiation include xenon lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, and ultraviolet light lasers such as KrF and ArF. High-pressure mercury lamps, ultra-high-pressure mercury lamps and metal halide lamps are more preferred. preferable. Among these, high-pressure mercury lamps, ultra-high-pressure mercury lamps, and metal halide lamps are preferable because of their high emission intensity of ultraviolet rays having a wavelength of 313 nm. Polarized UV can be emitted by passing light from a light source through a suitable polarizer. As such a polarizer, a polarizing filter, a polarizing prism such as Glan-Thompson or Glan-Taylor, or a wire grid type polarizer can be used.

A plurality of regions (patterns) having different alignment directions of the liquid crystal compound can be formed by masking during rubbing or polarized light irradiation.

A groove alignment film is a film having an uneven pattern or a plurality of grooves on its surface. When a polymerizable liquid crystal compound is applied to a film having a plurality of linear grooves arranged at regular intervals, liquid crystal molecules are aligned along the grooves.

As a method for obtaining a grooved alignment film, after exposure through an exposure mask having pattern-shaped slits on the surface of a photosensitive polyimide film, development and rinsing are performed to form an uneven pattern, and a plate having grooves on the surface. A method of forming a UV curable resin layer before curing on a shaped master, transferring the formed resin layer to a substrate and then curing, and a UV curable resin film before curing formed on the substrate, A method of pressing a roll-shaped master plate having a plurality of grooves to form unevenness and then curing the same may be used.

As a material exhibiting an alignment control force for aligning the polymerizable liquid crystal compound in the direction perpendicular to the plane of the coating film, in addition to the above-mentioned aligning polymers, fluorine-based polymers such as perfluoroalkyl, silane compounds, and their condensation reactions. You may use the polysiloxane compound etc. which are obtained by.

When a silane compound is used as the material for forming the alignment film, the constituent elements include Si element and C element from the viewpoint of easily reducing the surface tension and increasing the adhesion to the layer adjacent to the alignment film. Compounds are preferred, and silane compounds can be suitably used. As the silane compound, it is possible to use a nonionic silane compound, which will be described later, or a silane-containing ionic compound, which is exemplified as an ionic compound, which will be described later. can increase These silane compounds may be used singly, in combination of two or more, or in combination with other materials. When the silane compound is a nonionic silane compound, a silane compound having an alkyl group at the molecular end is preferable, and a silane compound having an alkyl group having 3 to 30 carbon atoms is more preferable, from the viewpoint of easily increasing the vertical alignment control force. .

The thickness of the alignment film (orientation film containing an alignment polymer or photo-alignment film) is usually in the range of 10 to 10000 nm, preferably in the range of 10 to 1000 nm, more preferably in the range of 10 to 500 nm, still more preferably. is in the range from 10 to 300 nm, particularly preferably from 50 to 250 nm.

The coating film of the polymerizable liquid crystal composition may be formed directly on the substrate without using an alignment film. Forming a coating film of a polymerizable liquid crystal composition directly on a substrate does not require a step of forming an alignment film, which is advantageous in terms of production efficiency and production cost. In this case, the polymerizable liquid crystal composition for forming the dye-containing layer usually contains an alignment promoter. An alignment promoter means a material that promotes liquid crystal alignment of a polymerizable liquid crystal compound in a desired direction.

Examples of the alignment promoter for promoting alignment of the polymerizable liquid crystal compound in the vertical direction include ionic compounds and nonionic silane compounds composed of non-metal atoms. The polymerizable liquid crystal composition forming the dye-containing layer preferably contains at least one of an ionic compound consisting of nonmetallic atoms and a nonionic silane compound, and the ionic compound consisting of nonmetallic atoms and the nonionic It is more preferable to include both a silane compound.

A dry coating film formed on a substrate using a polymerizable liquid crystal composition for forming a dye-containing layer when the polymerizable liquid crystal composition for forming the dye-containing layer contains an ionic compound composed of nonmetallic atoms. In this case, the electrostatic interaction exerts a force for controlling the vertical alignment of the polymerizable liquid crystal compound, and the polymerizable liquid crystal compound tends to be aligned in the vertical direction with respect to the substrate surface in the dried coating film. As a result, the dye-containing layer can be formed while maintaining the vertically aligned state of the polymerizable liquid crystal compound.

Examples of ionic compounds composed of non-metal atoms include onium salts (more specifically, quaternary ammonium salts, tertiary sulfonium salts in which the nitrogen atom has a positive charge, and phosphorus atoms in which the phosphorus atom has a positive charge). quaternary phosphonium salts, etc.). Among these onium salts, quaternary onium salts are preferred from the viewpoint of further improving the vertical alignment properties of the polymerizable liquid crystal compound, and from the viewpoint of improving availability and mass productivity, quaternary phosphonium salts or quaternary onium salts are preferred. Ammonium salts are more preferred. The onium salt may have two or more quaternary onium salt sites in the molecule, and may be an oligomer or polymer.

The molecular weight of the ionic compound is preferably 100 or more and 10,000 or less. When the molecular weight is within the above range, it is easy to improve the vertical alignment property of the polymerizable liquid crystal compound while ensuring the applicability of the polymerizable liquid crystal composition. The molecular weight of the ionic compound is more preferably 5000 or less, still more preferably 3000 or less.

Cationic components of ionic compounds include, for example, inorganic cations and organic cations. Among them, organic cations are preferable because they hardly cause alignment defects in the polymerizable liquid crystal compound. Examples of organic cations include imidazolium cations, pyridinium cations, ammonium cations, sulfonium cations and phosphonium cations.

Ionic compounds generally have a counter anion. Examples of the anion component that serves as a counterion for the cation component include inorganic anions and organic anions. Among them, an organic anion is preferable because it hardly causes an alignment defect of the polymerizable liquid crystal compound. Note that cations and anions do not necessarily have to correspond one-to-one.

Specific examples of the anion component include the following.
chloride anion [Cl ⁻ ],
bromide anion [Br ⁻ ],
iodide anion [I ⁻ ],
tetrachloroaluminate anion [AlCl ₄ ⁻ ],
heptachlorodialuminate anion [Al ₂ Cl ₇ ⁻ ],
tetrafluoroborate anion [BF ₄ ⁻ ],
hexafluorophosphate anion [PF ₆ ⁻ ],
perchlorate anion [ClO ₄ ⁻ ],
nitrate anion [NO ₃ ⁻ ],
Acetate anion [CH ₃ COO ⁻ ],
trifluoroacetate anion [CF ₃ COO ⁻ ],
fluorosulfonate anion [FSO ₃ ⁻ ],
methanesulfonate anion [CH ₃ SO ₃ ⁻ ],
trifluoromethanesulfonate anion [CF ₃ SO ₃ ⁻ ],
p-toluenesulfonate anion [p-CH ₃ C ₆ H ₄ SO ₃ ⁻ ],
bis(fluorosulfonyl)imide anion [(FSO ₂ ) ₂ N ⁻ ],
bis(trifluoromethanesulfonyl)imide anion [(CF ₃ SO ₂ ) ₂ N ⁻ ],
tris(trifluoromethanesulfonyl)methanide anion [(CF ₃ SO ₂ ) ₃ C ⁻ ],
hexafluoroarsenate anion [AsF ₆ ⁻ ],
hexafluoroantimonate anion [SbF ₆ ⁻ ],
hexafluoroniobate anion [NbF ₆ ⁻ ],
hexafluorotantalate anion [TaF ₆ ⁻ ],
dimethylphosphinate anion [(CH ₃ ) ₂ POO ⁻ ],
(poly)hydrofluorofluoride anion [F(HF) _n ⁻ ] (for example, n represents an integer of 1 to 3),
dicyanamide anion [(CN) ₂ N ⁻ ],
thiocyan anion [SCN ^- ],
perfluorobutanesulfonate anion [C ₄ F ₉ SO ₃ ⁻ ],
bis(pentafluoroethanesulfonyl)imide anion [(C ₂ F ₅ SO ₂ ) ₂ N ⁻ ],
perfluorobutanoate anion [C ₃ F ₇ COO ⁻ ], and
(trifluoromethanesulfonyl)(trifluoromethanecarbonyl)imide anion [(CF ₃ SO ₂ )(CF ₃ CO)N ⁻ ].

Specific examples of the ionic compound can be appropriately selected from combinations of the above cationic components and anionic components. Specific examples of compounds that are combinations of cationic components and anionic components include the following.

(pyridinium salt)
N-hexylpyridinium hexafluorophosphate,
N-octylpyridinium hexafluorophosphate,
N-methyl-4-hexylpyridinium hexafluorophosphate,
N-butyl-4-methylpyridinium hexafluorophosphate,
N-octyl-4-methylpyridinium hexafluorophosphate,
N-hexylpyridinium bis(fluorosulfonyl)imide,
N-octylpyridinium bis(fluorosulfonyl)imide,
N-methyl-4-hexylpyridinium bis(fluorosulfonyl)imide,
N-butyl-4-methylpyridinium bis(fluorosulfonyl)imide,
N-octyl-4-methylpyridinium bis(fluorosulfonyl)imide,
N-hexylpyridinium bis(trifluoromethanesulfonyl)imide,
N-octylpyridinium bis(trifluoromethanesulfonyl)imide,
N-methyl-4-hexylpyridinium bis(trifluoromethanesulfonyl)imide,
N-butyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imide,
N-octyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imide,
N-hexylpyridinium p-toluenesulfonate,
N-octylpyridinium p-toluenesulfonate,
N-methyl-4-hexylpyridinium p-toluenesulfonate,
N-butyl-4-methylpyridinium p-toluenesulfonate, and
N-octyl-4-methylpyridinium p-toluenesulfonate.

(imidazolium salt)
1-ethyl-3-methylimidazolium hexafluorophosphate,
1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide,
1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide,
1-ethyl-3-methylimidazolium p-toluenesulfonate,
1-butyl-3-methylimidazolium methanesulfonate, and the like.

(Pyrrolidinium salt)
N-butyl-N-methylpyrrolidinium hexafluorophosphate,
N-butyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide,
N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide,
N-butyl-N-methylpyrrolidinium p-toluenesulfonate, and the like.

(ammonium salt)
tetrabutylammonium hexafluorophosphate,
tetrabutylammonium bis(fluorosulfonyl)imide,
tetrahexylammonium bis(fluorosulfonyl)imide,
trioctylmethylammonium bis(fluorosulfonyl)imide,
(2-hydroxyethyl)trimethylammonium bis(fluorosulfonyl)imide,
tetrabutylammonium bis(trifluoromethanesulfonyl)imide,
tetrahexylammonium bis(trifluoromethanesulfonyl)imide,
trioctylmethylammonium bis(trifluoromethanesulfonyl)imide,
(2-hydroxyethyl)trimethylammonium bis(trifluoromethanesulfonyl)imide,
tetrabutylammonium p-toluenesulfonate,
tetrahexylammonium p-toluenesulfonate,
trioctylmethylammonium p-toluenesulfonate,
(2-hydroxyethyl)trimethylammonium p-toluenesulfonate,
(2-hydroxyethyl)trimethylammonium dimethylphosphinate,
1-(3-trimethoxysilylpropyl)-1,1,1-tributylammonium bis(trifluoromethanesulfonyl)imide,
1-(3-trimethoxysilylpropyl)-1,1,1-trimethylammonium bis(trifluoromethanesulfonyl)imide,
1-(3-trimethoxysilylbutyl)-1,1,1-tributylammonium bis(trifluoromethanesulfonyl)imide,
1-(3-trimethoxysilylbutyl)-1,1,1-trimethylammonium bis(trifluoromethanesulfonyl)imide,
N-{(3-triethoxysilylpropyl)carbamoyloxyethyl)}-N,N,N-trimethylammonium bis(trifluoromethanesulfonyl)imide, and
N-[2-{3-(3-trimethoxysilylpropylamino)-1-oxopropoxy}ethyl]-N,N,N-trimethylammonium bis(trifluoromethanesulfonyl)imide.

(Phosphonium salt)
tributyl(2-methoxyethyl)phosphonium bis(trifluoromethanesulfonyl)imide,
tributylmethylphosphonium bis(trifluoromethanesulfonyl)imide,
1,1,1-trimethyl-1-[(trimethoxysilyl)methyl]phosphonium bis (trifluoromethanesulfonyl)imide,
1,1,1-trimethyl-1-[2-(trimethoxysilyl)ethyl]phosphonium bis(trifluoromethanesulfonyl)imide,
1,1,1-trimethyl-1-[3-(trimethoxysilyl)propyl]phosphonium bis(trifluoromethanesulfonyl)imide,
1,1,1-trimethyl-1-[4-(trimethoxysilyl)butyl]phosphonium bis(trifluoromethanesulfonyl)imide,
1,1,1-tributyl-1-[(trimethoxysilyl)methyl]phosphonium bis(trifluoromethanesulfonyl)imide,
1,1,1-tributyl-1-[2-(trimethoxysilyl)ethyl]phosphonium bis(trifluoromethanesulfonyl)imide, and
1,1,1-tributyl-1-[3-(trimethoxysilyl)propyl]phosphoniu bis(trifluoromethanesulfonyl)imide.

These ionic compounds may be used alone or in combination of two or more.

From the viewpoint of further improving the vertical alignment property of the polymerizable liquid crystal compound, the ionic compound preferably has Si element and/or F element in the molecular structure of the cation site. When the ionic compound has Si element and/or F element in the molecular structure of the cation site, the ionic compound tends to segregate on the surface of the dye-containing layer. Among them, the following ionic compounds (Ii) to (I-iii) and the like are preferable as ionic compounds whose constituent elements are all non-metallic elements.

(Ionic compound (Ii))

(Ionic compound (I-ii))

(Ionic compound (I-iii))

As a method for improving the vertical alignment property of a polymerizable liquid crystal compound, for example, a method of treating the substrate surface with a surfactant having an alkyl group having a long chain length to some extent is known (see, for example, "Liquid Crystal Handbook"). Chapter 2 Orientation and physical properties of liquid crystals (published by Maruzen Co., Ltd.), etc.). The method of improving the vertical alignment property of liquid crystal compounds using such surfactants can also be applied to ionic compounds. That is, by treating the base material surface with an ionic compound having an alkyl group with a relatively long chain length, the vertical orientation of the polymerizable liquid crystal compound can be effectively improved.

Specifically, the ionic compound preferably satisfies the relationship of the following formula (8).
5<M<16 (8)
[In formula (8), M is represented by the following formula (9).
M = (Number of covalent bonds from the positively charged atom to the molecular chain end of the substituent with the largest number of covalent bonds to the molecular chain end among the substituents directly bonded to the positively charged atom ) ÷ (number of atoms with positive charge) (9)]

When the ionic compound satisfies the relationship of the formula (8), the vertical alignment property of the polymerizable liquid crystal compound can be effectively improved.

When there are two or more positively charged atoms in the molecule of an ionic compound, for substituents having two or more positively charged atoms, The number of covalent bonds to another nearby positively charged atom is defined as "the number of covalent bonds from the positively charged atom to the end of the molecular chain" described in the definition of M above. Further, when the ionic compound is an oligomer or polymer having two or more repeating units, the above M is calculated considering the constituent unit as one molecule. When a positively charged atom is incorporated into a ring structure, the number of covalent bonds through the ring structure to the positively charged atom, or to the end of a substituent attached to the ring structure. Among the number of covalent bonds, the one with the larger number of covalent bonds is defined as "the number of covalent bonds from the positively charged atom to the end of the molecular chain" described in the definition of M above.

When the polymerizable liquid crystal composition forming the dye-containing layer contains an ionic compound, the content thereof is usually preferably 0.01 to 5% by mass based on the solid content of the polymerizable liquid crystal composition. It is more preferably 0.05 to 4% by mass, even more preferably 0.1 to 3% by mass. When the content of the ionic compound is within the above range, it is possible to effectively promote vertical alignment of the polymerizable liquid crystal compound while maintaining good applicability of the polymerizable liquid crystal composition.

When the polymerizable liquid crystal composition forming the dye-containing layer contains a nonionic silane compound, the nonionic silane compound reduces the surface tension of the polymerizable liquid crystal composition, and the dye-containing layer is formed on the substrate. In the dry coating film formed from the polymerizable liquid crystal composition, the nonionic silane compound is present on the surface of the dry coating film opposite to the base material, and the vertical alignment regulating force for the polymerizable liquid crystal compound is increased. In the coating film, the polymerizable liquid crystal compound tends to be oriented in the direction perpendicular to the substrate surface. As a result, the dye-containing layer can be formed while maintaining the vertically aligned state of the polymerizable liquid crystal compound.

A nonionic silane compound is a compound that is nonionic and contains Si element. Nonionic silane compounds include, for example, silicon polymers such as polysilanes, silicone resins such as silicone oils and silicone resins, and organic and inorganic silane compounds such as silicone oligomers, silsessiloxanes and alkoxysilanes (more specifically, includes silane coupling agents, etc.), silane-containing compounds exemplified as leveling agents, and the like.

The nonionic silane compound may be of the silicone monomer type or of the silicone oligomer (polymer) type. In the form of (monomer)-(monomer) copolymer, the silicone oligomers are 3-mercaptopropyltrimethoxysilane-tetramethoxysilane copolymer, 3-mercaptopropyltrimethoxysilane-tetraethoxysilane copolymer, 3-mercapto Mercaptopropyl group-containing copolymers such as propyltriethoxysilane-tetramethoxysilane copolymer and 3-mercaptopropyltriethoxysilane-tetraethoxysilane copolymer; Mercaptomethyl group-containing copolymers such as ethoxysilane copolymers, mercaptomethyltriethoxysilane-tetramethoxysilane copolymers and mercaptomethyltriethoxysilane-tetraethoxysilane copolymers; 3-methacryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymers, 3 -Methacryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer, 3-methacryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer, 3-methacryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer, 3-methacryloyloxypropylmethyldimethoxysilane- Tetramethoxysilane Copolymer, 3-Methacryloyloxypropylmethyldimethoxysilane-Tetraethoxysilane Copolymer, 3-Methacryloyloxypropylmethyldiethoxysilane-Tetramethoxysilane Copolymer and 3-Methacryloyloxypropylmethyldiethoxysilane-Tetraethoxysilane Copolymer 3-acryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer, 3-acryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer, 3-acryloyloxypropyltriethoxysilane-tetramethoxy Silane Copolymer, 3-Acryloyloxypropyltriethoxysilane-Tetraethoxysilane Copolymer, 3-Acryloyloxypropylmethyldimethoxysilane-Tetramethoxysilane Copolymer, 3-Acryloyloxypropylmethyldimethoxysilane-Tetraethoxysilane Copolymer, 3-Acryloyloxypropyl acryloyloxypropyl group-containing copolymers such as methyldiethoxysilane-tetramethoxysilane copolymer and 3-acryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer; vinyltrimethoxysilane-tetramethoxysilane copolymer, vinyltrimethoxysilane -tetraethoxysilane copolymer, vinyltriethoxysilane-tetramethoxysilane copolymer, vinyltriethoxysilane-tetraethoxysilane copolymer, vinylmethyldimethoxysilane-tetramethoxysilane copolymer, vinylmethyldimethoxysilane-tetraethoxysilane copolymer, vinylmethyldiethoxy Vinyl group-containing copolymers such as silane-tetramethoxysilane copolymer and vinylmethyldiethoxysilane-tetraethoxysilane copolymer; 3-aminopropyltrimethoxysilane-tetramethoxysilane copolymer, 3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer, 3-aminopropyltriethoxysilane-tetramethoxysilane copolymer, 3-aminopropyltriethoxysilane-tetraethoxysilane copolymer, 3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer, 3-aminopropylmethyldimethoxysilane-tetra Amino group-containing copolymers such as ethoxysilane copolymers, 3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymers and 3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymers, and the like. These nonionic silane compounds may be used singly or in combination of two or more. Among them, the silane coupling agent is preferable from the viewpoint of further improving the adhesion with the adjacent layer.

The silane coupling agent is selected from the group consisting of vinyl group, epoxy group, styryl group, methacrylic group, acrylic group, amino group, isocyanurate group, ureido group, mercapto group, isocyanate group, carboxyl group, and hydroxy group at the terminal. and at least one alkoxysilyl group or silanol group. By appropriately selecting these functional groups, it is possible to improve the mechanical strength of the dye-containing layer, modify the surface of the dye-containing layer, and improve the adhesion between the dye-containing layer and an adjacent layer (for example, a substrate). effect can be given. From the viewpoint of adhesion, the silane coupling agent is preferably a silane coupling agent having an alkoxysilyl group and another different reactive group (for example, the functional group described above). Furthermore, the silane coupling agent is preferably a silane coupling agent having an alkoxysilyl group and a polar group. When the silane coupling agent has at least one alkoxysilyl group and at least one polar group in its molecule, the vertical alignment property of the polymerizable liquid crystal compound can be more easily improved, and the effect of promoting vertical alignment can be significantly obtained. There is a tendency. Polar groups include, for example, epoxy groups, amino groups, isocyanurate groups, mercapto groups, carboxy groups and hydroxy groups. In addition, the polar group may have an appropriate substituent or protective group in order to control the reactivity of the silane coupling agent.

Specific examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, 3-glycidoxypropyltri Methoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltri Methoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyldimethoxymethylsilane, and 3-glycidoxypropylethoxydimethylsilane Silanes are mentioned.

Commercially available silane coupling agents include, for example, KP321, KP323, KP324, KP326, KP340, KP341, X22-161A, KF6001, KBM-1003, KBE-1003, KBM-303, KBM-402, KBM-403, KBE -402, KBE-403, KBM-1403, KBM-502, KBM-503, KBE-502, KBE-503, KBM-5103, KBM-602, KBM-603, KBM-903, KBE-903, KBE-9103 , KBM-573, KBM-575, KBM-9659, KBE-585, KBM-802, KBM-803, KBE-846, and KBE-9007. be done.

When the polymerizable liquid crystal composition forming the dye-containing layer contains a nonionic silane compound, the content thereof is usually 0.01% by mass to 5% by mass with respect to the solid content of the polymerizable liquid crystal composition. preferably 0.05% by mass to 4% by mass, and even more preferably 0.1% by mass to 3% by mass. When the content of the nonionic silane compound is within the above range, it is possible to effectively promote vertical alignment of the polymerizable liquid crystal compound while maintaining good applicability of the polymerizable liquid crystal composition.

Since the polymerizable liquid crystal composition forming the dye-containing layer contains both an ionic compound and a nonionic silane compound, in a dry coating film formed from the polymerizable liquid crystal composition on a substrate, ions Due to the electrostatic interaction derived from the ionic compound and the effect of lowering the surface tension derived from the nonionic silane compound, the vertical alignment of the polymerizable liquid crystal compound is more likely to be promoted. As a result, the dye-containing layer can be formed while the polymerizable liquid crystal compound is maintained in a vertically aligned state with higher accuracy.

(Stretched film constituting retardation layer)
As the stretched film constituting the retardation layer, a conventionally known one can be used, and a resin film to which an in-plane retardation is imparted by uniaxially or biaxially stretching can be used. Examples of resin films include cellulose films such as triacetylcellulose and diacetylcellulose, polyester films such as polyethylene terephthalate, polyethylene isophthalate and polybutylene terephthalate, and acrylic resin films such as polymethyl (meth)acrylate and polyethyl (meth)acrylate. , polycarbonate-based films, polyethersulfone-based films, polysulfone-based films, polyimide-based films, polyolefin-based films, polynorbornene-based films, and the like can be used, but are not limited to these.

(Horizontal alignment liquid crystal layer)
Conventionally known polymerizable liquid crystal compounds can be used as the polymerizable liquid crystal compound used for forming the horizontally aligned liquid crystal layer constituting the retardation layer. Among them, a polymerizable liquid crystal compound exhibiting so-called reverse wavelength dispersion is preferable, and as such a polymerizable liquid crystal compound, for example, a compound represented by the above formula (X) can be preferably used. A polymerizable liquid crystal compound can be used individually or in combination of 2 or more types.

The content of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition used for forming the horizontal alignment liquid crystal layer is, for example, 70 to 99.5 parts by mass with respect to 100 parts by mass of the solid content of the polymerizable liquid crystal composition, It is preferably 80 to 99 parts by mass, more preferably 85 to 98 parts by mass, still more preferably 90 to 95 parts by mass. If the content of the polymerizable liquid crystal compound is within the above range, it is advantageous from the viewpoint of the orientation of the horizontal alignment liquid crystal layer to be obtained.

In addition to the polymerizable liquid crystal compound, the polymerizable liquid crystal composition used for forming the horizontal alignment liquid crystal layer further contains additives such as a solvent, a photopolymerization initiator, a leveling agent, an antioxidant, and a photosensitizer. good too. Examples of these components include those previously exemplified as components that can be used in the dye-containing layer, and each of them may be used alone or in combination of two or more.

The polymerizable liquid crystal composition used for forming the horizontal alignment liquid crystal layer can be obtained by stirring a polymerizable liquid crystal compound and components other than the polymerizable liquid crystal compound such as a solvent and a photopolymerization initiator at a predetermined temperature. .

For example, the horizontally aligned liquid crystal layer is
obtaining a coating film by applying a polymerizable liquid crystal compound for forming a horizontally aligned liquid crystal layer onto a substrate or an alignment film;
A step of drying the coating film to form a dry coating film, and
It can be produced by a method including a step of irradiating a dry coating film with an active energy ray to form a horizontally aligned liquid crystal layer.

The coating film of the polymerizable liquid crystal composition can be formed, for example, by applying the polymerizable liquid crystal composition for forming the horizontally aligned liquid crystal layer on the base material, the alignment film, or the like. As the base material that can be used here, those exemplified above as the base material that can be used in the production of the dye-containing layer can be used.

As the alignment film, a horizontal alignment film having a horizontal alignment regulating force for aligning the polymerizable liquid crystal compound in the horizontal direction with respect to the plane of the coating film can be used. The alignment regulation force can be arbitrarily adjusted by the type of alignment film, surface condition, rubbing conditions, etc., and in the case of being formed from a photo-orientable polymer, it can be arbitrarily adjusted by polarized irradiation conditions, etc. It is possible. Such materials include, for example, the oriented polymer described as the oriented film that can be used in the production of the dye-containing layer. A horizontal alignment film is formed by coating a substrate with a composition containing a material having a horizontal alignment regulating force and a solvent (for example, the solvent exemplified in the dye-containing layer), removing the solvent, and subjecting the coating film to a drying treatment. Obtainable. From the viewpoint of quality, it is preferable to use a photo-alignment film as the horizontal alignment film.

Examples of the drying method include natural drying, ventilation drying, heat drying, and reduced pressure drying. From the viewpoint of productivity, drying by heating is preferable, and the heating temperature in that case is preferably equal to or higher than the phase transition temperature of the polymerizable liquid crystal compound and the solvent can be removed. Procedures and conditions in such steps include procedures and conditions that can be employed in the production of the dye-containing layer.

The obtained dried coating film is irradiated with an active energy ray (more specifically, ultraviolet rays, etc.), and the polymerizable liquid crystal compound is irradiated while maintaining the state in which the polymerizable liquid crystal compound is aligned in the horizontal direction with respect to the plane of the coating film. is polymerized to form a horizontally aligned liquid crystal layer. Polymerization methods include methods that can be employed in the production of the dye-containing layer.

(Stretched film constituting polarizing layer)
The polarizing layer may be a stretched film to which a dye having absorption anisotropy is adsorbed. A polarizing layer composed of such a stretched film is usually obtained by uniaxially stretching a polyvinyl alcohol resin film and dyeing the polyvinyl alcohol resin film with a dye having anisotropic absorption. a step of adsorbing a dye having anisotropic absorption, a step of treating a polyvinyl alcohol-based resin film adsorbed with a dye having anisotropic absorption with an aqueous boric acid solution, and a step of washing with water after treatment with an aqueous boric acid solution. . The polarizing layer may be incorporated into the optical laminate as a polarizing plate having a transparent protective film laminated on one side or both sides via an adhesive.

A polyvinyl alcohol-based resin is obtained by saponifying a polyvinyl acetate-based resin. Polyvinyl acetate-based resins include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate with other monomers copolymerizable therewith. Other monomers copolymerizable with vinyl acetate include, for example, unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.

The degree of saponification of the polyvinyl alcohol resin is usually about 85 to 100 mol %, preferably 98 mol % or more. The polyvinyl alcohol-based resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The degree of polymerization of the polyvinyl alcohol resin is generally about 1,000 to 10,000, preferably 1,500 to 5,000.

A film obtained by forming such a polyvinyl alcohol-based resin is used as a raw film for the polarizing layer. The method of forming the polyvinyl alcohol-based resin into a film is not particularly limited, and the film can be formed by a known method. The film thickness of the polyvinyl alcohol-based raw film can be, for example, about 10 to 150 μm.

The uniaxial stretching of the polyvinyl alcohol-based resin film can be performed before, at the same time as, or after dyeing with a dye having anisotropic absorption. When uniaxial stretching is performed after dyeing, this uniaxial stretching may be performed before boric acid treatment or during boric acid treatment. It is also possible to carry out uniaxial stretching in these multiple stages. In the uniaxial stretching, the film may be uniaxially stretched between rolls having different circumferential speeds, or may be uniaxially stretched using hot rolls. The uniaxial stretching may be dry stretching in which the film is stretched in the atmosphere, or wet stretching in which the polyvinyl alcohol resin film is stretched in a swollen state using a solvent. The draw ratio is usually about 3 to 8 times.

Dyeing a polyvinyl alcohol resin film with a dye having anisotropic absorption is performed, for example, by immersing the polyvinyl alcohol resin film in an aqueous solution containing a dye having anisotropic absorption.

Specifically, iodine and dichroic organic dyes are used as dyes having absorption anisotropy. Dichroic organic dyes include C.I. I. Dichroic direct dyes composed of disazo compounds such as DIRECT RED 39, and dichroic direct dyes composed of compounds such as trisazo and tetrakisazo are included. The polyvinyl alcohol-based resin film is preferably immersed in water before dyeing.

When iodine is used as a dye having anisotropic absorption, a method of dyeing a polyvinyl alcohol-based resin film by immersing it in an aqueous solution containing iodine and potassium iodide is usually employed. The content of iodine in this aqueous solution is usually about 0.01 to 1 part by mass per 100 parts by mass of water. Also, the content of potassium iodide is usually about 0.5 to 20 parts by mass per 100 parts by mass of water. The temperature of the aqueous solution used for dyeing is usually about 20 to 40°C. The immersion time (dyeing time) in this aqueous solution is usually about 20 to 1,800 seconds.

On the other hand, when a dichroic organic dye is used as a dye having anisotropic absorption, a method of dyeing by immersing a polyvinyl alcohol-based resin film in an aqueous solution containing a water-soluble dichroic dye is usually employed. The content of the dichroic organic dye in the aqueous solution is usually about 1×10 ⁻⁴ to 10 parts by weight, preferably 1×10 ⁻³ to 1 part by weight, per 100 parts by weight of water. It is preferably 1×10 ⁻³ to 1×10 ⁻² parts by mass. This aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing aid. The temperature of the aqueous solution containing the dichroic dye used for dyeing is usually about 20 to 80°C. The immersion time (dyeing time) in this aqueous solution is usually about 10 to 1,800 seconds.

The boric acid treatment after dyeing with a dye having anisotropic absorption can usually be carried out by immersing the dyed polyvinyl alcohol-based resin film in an aqueous boric acid solution. The content of boric acid in the boric acid aqueous solution is usually about 2 to 15 parts by mass, preferably 5 to 12 parts by mass, per 100 parts by mass of water. When iodine is used as a dye having absorption anisotropy, the boric acid aqueous solution preferably contains potassium iodide. .1 to 15 parts by mass, preferably 5 to 12 parts by mass. The immersion time in the boric acid aqueous solution is usually about 60 to 1,200 seconds, preferably 150 to 600 seconds, more preferably 200 to 400 seconds. The temperature of boric acid treatment is usually 50°C or higher, preferably 50 to 85°C, more preferably 60 to 80°C.

The polyvinyl alcohol-based resin film after boric acid treatment is usually washed with water. The water washing treatment can be performed, for example, by immersing the boric acid-treated polyvinyl alcohol-based resin film in water. The temperature of water in the water washing process is usually about 5 to 40°C. The immersion time is usually about 1 to 120 seconds.

After washing with water, a drying treatment is performed to obtain a polarizing layer. The drying treatment can be performed using, for example, a hot air dryer or a far-infrared heater. The drying temperature is usually about 30 to 100°C, preferably 50 to 80°C. The drying time is usually about 60 to 600 seconds, preferably 120 to 600 seconds. The drying process reduces the moisture content of the polarizing layer to a practical level. Its moisture content is usually about 5 to 20% by weight, preferably 8 to 15% by weight. If the moisture content is less than 5% by weight, the flexibility of the polarizing layer may be lost and the polarizing layer may be damaged or broken after drying. Moreover, when the moisture content exceeds 20% by weight, the thermal stability of the polarizing layer may deteriorate.

The thickness of the polarizing layer obtained by subjecting the polyvinyl alcohol resin film to uniaxial stretching, dyeing with a dye having absorption anisotropy, boric acid treatment, washing with water and drying is preferably 5 to 40 μm.

(Polarizing layer formed by coating a base film with a dye having absorption anisotropy)
A polarizing layer formed by coating a base film with a dye having anisotropic absorption may be a composition containing a dye having liquid crystallinity and anisotropic absorption, or a dye having anisotropic absorption and a polymerizable liquid crystal. and a polarizing layer obtained by coating a base film with a composition containing Examples of the substrate film include those exemplified above as substrates that can be used in the production of the dye-containing layer.

The total thickness of the substrate film and the polarizing layer formed as described above is preferably as small as possible. or less, more preferably 0.5 to 3 μm.

Specific examples of the polarizing layer include those described in JP-A-2013-33249.

The polarizing layer obtained as described above (a stretched film, a polarizing layer formed by coating a base film with a dye having anisotropic absorption) is coated with a transparent protective film on one or both sides thereof via an adhesive. The laminated polarizing plate may be incorporated into the optical laminate. As the second protective film 152 and the second hard coat layer 162 that constitute the transparent protective film, those exemplified above as the base material that can be used in the production of the dye-containing layer, and the protective film and the hard coat layer that will be described later. Those exemplified can be preferably used. In the polarizing layer formed by coating a base film with a dye having anisotropic absorption, the above-described base film may be used as a transparent protective film.

(Hard coat layer (first hard coat layer))
A hard coat layer (first hard coat layer) can be provided on the opposite side of the dye-containing layer to the polarizing layer in order to protect the surface of the dye-containing layer. The hard coat layer is preferably a cured product layer of any suitable UV-curable resin. Examples of UV curable resins include acrylic resins, silicone resins, polyester resins, urethane resins, amide resins, and epoxy resins. The hard coat layer may contain any appropriate additive as necessary. Typical examples of the additive include inorganic fine particles and/or organic fine particles. By including fine particles, for example, a suitable refractive index can be provided.

The thickness of the hard coat layer can be set to any appropriate value. It is preferably 50 μm or less, more preferably 1 to 50 μm, still more preferably 1 to 40 μm, particularly preferably 1 to 30 μm. The hard coat layer preferably has a pencil hardness of 4H or more, more preferably 5H to 8H.

The hard coat layer is typically provided in the optical layered body in the state of forming a layered body by subjecting a base material such as a protective film (first protective film) to hard coating treatment. As the base material, the base material used in the method for producing the dye-containing layer described above can be used in addition to the resin film described in the later-described protective film.

The hard coat layer may be formed by coating the surface of the dye-containing layer or the surface of the protective film with the above-described UV-curable resin.

(Protective film (first protective film))
A protective film (first protective film) can be provided on the opposite side of the dye-containing layer from the polarizing layer side in order to protect the surface of the dye-containing layer. Any appropriate film can be adopted as the protective film. Specific examples of the material that is the main component of the film include cellulose resins such as triacetyl cellulose (TAC), polyesters, polyvinyl alcohols, polycarbonates, polyamides, polyimides, polyethersulfones, polysulfones, Examples include transparent resins such as polystyrene, polynorbornene, polyolefin, (meth)acrylic, and acetate. Thermosetting resins such as (meth)acrylic, urethane, (meth)acrylic urethane, epoxy, and silicone, or ultraviolet curable resins may also be used. In addition, for example, a glassy polymer such as a siloxane-based polymer can also be used. Further, polymer films described in JP-A-2001-343529 (International Publication No. 2001/37007) can also be used. Materials for this film include, for example, a thermoplastic resin having a substituted or unsubstituted imide group in the side chain and a thermoplastic resin having a substituted or unsubstituted phenyl group and nitrile group in the side chain. can be used, for example, a resin composition comprising an alternating copolymer of isobutene and N-methylmaleimide and an acrylonitrile/styrene copolymer. The polymer film can be, for example, an extrudate of the resin composition. As used herein, (meth)acrylic refers to acrylic and/or methacrylic.

The (meth)acrylic resin has a Tg (glass transition temperature) of preferably 115° C. or higher, more preferably 120° C. or higher, still more preferably 125° C. or higher, and particularly preferably 130° C. or higher. It is because durability can be excellent. Although the upper limit of Tg of the (meth)acrylic resin is not particularly limited, it is preferably 170° C. or less from the viewpoint of moldability and the like.

As the (meth)acrylic resin, any suitable (meth)acrylic resin can be adopted as long as the effects of the present invention are not impaired. For example, poly(meth)acrylic acid ester such as polymethyl methacrylate, methyl methacrylate-(meth)acrylic acid copolymer, methyl methacrylate-(meth)acrylic acid ester copolymer, methyl methacrylate-acrylic acid ester - (meth)acrylic acid copolymer, methyl (meth)acrylate-styrene copolymer (MS resin, etc.), polymer having an alicyclic hydrocarbon group (e.g., methyl methacrylate-cyclohexyl methacrylate copolymer , methyl methacrylate-norbornyl (meth)acrylate copolymer, etc.). Preferable examples include poly(meth)acrylic acid C1-6 alkyl such as polymethyl(meth)acrylate. Methyl methacrylate-based resins containing methyl methacrylate as a main component (50 to 100% by weight, preferably 70 to 100% by weight) are more preferred.

Specific examples of the (meth)acrylic resin include, for example, ACRYPET VH and ACRYPET VRL20A manufactured by Mitsubishi Rayon Co., Ltd., and (meth)acrylic resins having a ring structure in the molecule described in JP-A-2004-70296. Resins, and high Tg (meth)acrylic resins obtained by intramolecular cross-linking or intramolecular cyclization reaction can be mentioned.

As the (meth)acrylic resin, a (meth)acrylic resin having a lactone ring structure is particularly preferable because it has high heat resistance, high transparency, and high mechanical strength.

As the (meth)acrylic resin having the lactone ring structure, JP-A-2000-230016, JP-A-2001-151814, JP-A-2002-120326, JP-A-2002-254544, JP-A-2005 Examples include (meth)acrylic resins having a lactone ring structure, such as those described in JP-A-146084.

The (meth)acrylic resin having the lactone ring structure has a mass average molecular weight (also referred to as weight average molecular weight) of preferably 1,000 to 2,000,000, more preferably 5,000 to 1,000,000, still more preferably 10,000 to 500,000, especially It is preferably 50,000 to 500,000.

From the viewpoint of durability, the (meth)acrylic resin having a lactone ring structure has a Tg (glass transition temperature) of preferably 115° C. or higher, more preferably 125° C. or higher, even more preferably 130° C. or higher, and particularly preferably 130° C. or higher. is 135°C, most preferably 140°C or higher. Although the upper limit of the Tg of the (meth)acrylic resin having the lactone ring structure is not particularly limited, it is preferably 170° C. or less from the viewpoint of moldability and the like.

The protective film is preferably transparent and non-colored. The thickness direction retardation value Rth(590) of the protective film at a wavelength of 590 nm is preferably −90 nm to +90 nm, more preferably −80 nm to +80 nm, and still more preferably −70 nm to +70 nm.

The surface of the protective film opposite to the polarizing layer may be subjected to hard coat treatment, anti-reflection treatment, anti-sticking treatment, anti-glare treatment, or the like.

The thickness of the protective film can be any appropriate thickness, preferably 200 μm or less, more preferably 1 to 200 μm, still more preferably 3 to 150 μm, particularly preferably 5 to 100 μm. is.

(Lamination layer)
A known pressure-sensitive adhesive layer or adhesive layer can be used for the bonding layer provided in the optical laminate.

The adhesive layer is a layer formed using an adhesive. As used herein, the pressure-sensitive adhesive is a so-called pressure-sensitive adhesive that exhibits adhesiveness when it is attached to an adherend such as a panel. As the adhesive, a conventionally known adhesive having excellent optical transparency can be used without particular limitation. For example, an adhesive having a base polymer such as acrylic, urethane, silicone, or polyvinyl ether is used. be able to. The thickness of the adhesive layer may be 3 µm or more, 5 µm or more, or 35 µm or less, or 30 µm or less.

The adhesive layer contains additives such as ultraviolet absorbers, antistatic agents using ionic compounds, solvents, cross-linking catalysts, tackifying resins (tackifiers), plasticizers, softeners, dyes, pigments, and inorganic fillers. may contain.

The adhesive layer can be formed by curing a curable component in the adhesive. Adhesives for forming the adhesive layer include adhesives other than pressure-sensitive adhesives (adhesives), for example, water-based adhesives, active energy ray-curable adhesives such as UV-curable adhesives. mentioned.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "%" and "parts" in Examples and Comparative Examples are % by mass and parts by mass.

<Preparation of horizontal alignment liquid crystal layer (retardation layer)>
(1) Preparation of Composition for Forming Horizontal Alignment Film 5 parts of a photo-alignment material having the following structure (weight average molecular weight: 30000) and 95 parts of cyclopentanone (solvent) were mixed as components, and the resulting mixture was C. for 1 hour to obtain a composition for forming a horizontal alignment film.

(2) Preparation of Polymerizable Liquid Crystal Compounds A polymerizable liquid crystal compound (X1) and a polymerizable liquid crystal compound (X2) having the following molecular structures were prepared. Polymerizable liquid crystal compound (X1) was produced according to the method described in JP-A-2010-31223. Further, the polymerizable liquid crystal compound (X2) was produced according to the method described in JP-A-2009-173893.

Polymerizable liquid crystal compound (X1):

Polymerizable liquid crystal compound (X2):

A solution was obtained by dissolving 1 mg of the polymerizable liquid crystal compound (X1) in 50 mL of tetrahydrofuran. The resulting solution was placed in a measurement cell with an optical path length of 1 cm to prepare a measurement sample. The absorption spectrum was measured by setting the measurement sample in an ultraviolet-visible spectrophotometer (manufactured by Shimadzu Corporation "UV-2450"), and the wavelength at which the maximum absorption was obtained was read from the obtained absorption spectrum. The absorption maximum wavelength λmax in the range of 400 nm was 350 nm.

(3) Preparation of polymerizable liquid crystal composition (A1) for forming horizontal alignment liquid crystal layer The polymerizable liquid crystal compound (X1) and the polymerizable liquid crystal compound (X2) were mixed at a mass ratio of 90:10 to obtain a mixture. . With respect to 100 parts of the resulting mixture, 0.1 part of the leveling agent "BYK-361N" (manufactured by BM Chemie) and 2-dimethylamino-2-benzyl-1-(4-morpholinophenyl as a photopolymerization initiator ) 6 parts of butan-1-one (“Irgacure (registered trademark) 369 (Irg369)” manufactured by BASF Japan Ltd.) was added. Furthermore, N-methyl-2-pyrrolidone (NMP) was added so that the solid content concentration was 13%. The mixture was stirred at 80° C. for 1 hour to obtain a polymerizable liquid crystal composition (A1) for forming a horizontally aligned liquid crystal layer.

(4) Preparation of horizontal alignment liquid crystal layer COP film (ZF-14-50) manufactured by Nippon Zeon Co., Ltd. was subjected to corona treatment, and then the composition for forming a horizontal alignment film obtained above was coated with a bar coater. , dried at 80 ° C. for 1 minute, and subjected to polarized UV exposure using a polarized UV irradiation device (SPOT CURE SP-9; manufactured by Ushio Inc.) at a wavelength of 313 nm with an integrated light amount of 100 mJ / cm ² and horizontally aligned. A membrane was obtained. The film thickness of the resulting horizontal alignment film was measured with an ellipsometer and found to be 200 nm.

Subsequently, the polymerizable liquid crystal composition (A1) obtained above was applied using a bar coater on the horizontal alignment film, heated at 120° C. for 60 seconds, and then heated with a high-pressure mercury lamp (Unicure VB-15201BY-A, Ushio (manufactured by Denki Co., Ltd.), the surface coated with the polymerizable liquid crystal composition (A1) is irradiated with ultraviolet rays (in a nitrogen atmosphere, the integrated amount of light at a wavelength of 365 nm: 500 mJ/cm ² ), thereby forming a horizontally aligned liquid crystal layer. to obtain a laminate structure (A1) having a layer structure of COP film/horizontally aligned film/horizontally aligned liquid crystal layer. After confirming that there is no retardation in the COP film, using KOBRA-WPR manufactured by Oji Scientific Instruments Co., Ltd., the in-plane retardation value ReA (450) and When ReA(550) was measured, ReA(550) was 139 nm, and when ReA(450)/ReA(550) was calculated, it was 0.87.

<Preparation of dye-containing layer>
(5) Preparation of polymerizable liquid crystal composition (C1) for forming dye-containing layer As shown below, the following polymerizable liquid crystal compound (X3) and polymerizable liquid crystal compound (X4) were mixed at a mass ratio of 90:10. With respect to 100 parts of the mixture of polymerizable liquid crystal compounds, 0.25 parts of leveling agent "F-556" (manufactured by DIC), 0.9 parts of the following dichroic dye A, 2- as a photopolymerization initiator 6 parts of dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one ("Irgacure (registered trademark) 369 (Irg369)" manufactured by BASF Japan Ltd.) was added. Furthermore, o-xylene was added so that the solid content concentration was 25%. By stirring this mixture at 80° C. for 30 minutes, a polymerizable liquid crystal composition (C1) for forming a dye-containing layer was obtained.

Polymerizable liquid crystal compounds (X3) and (X4) are described in lub et al., Recl. Trav. Chim. It was synthesized according to the method described in Pays-Bas, 115, 321-328 (1996).

Polymerizable liquid crystal compound (X3):

Polymerizable liquid crystal compound (X4):

Dichroic dye A (maximum absorption wavelength 592 nm (measured in chloroform solution)):

(6) Preparation of dye-containing layer 1 A silane coupling agent “KBE-9103” (manufactured by Shin-Etsu Chemical Co., Ltd.) is dissolved in a mixed solvent in which ethanol and water are mixed at a ratio of 9:1 (weight ratio), A composition for forming a vertical alignment film having a solid concentration of 1% was obtained. HC-COP film 1 was prepared by forming a hard coat layer (HC layer) on a COP film (ZF-14-50) manufactured by Zeon Corporation. After corona treatment was applied to the hard coat layer side of this HC-COP film 1, a composition for forming a vertical alignment film was applied with a bar coater and dried at 120° C. for 1 minute to obtain a vertical alignment film. The film thickness of the resulting vertical alignment film was measured with an ellipsometer and found to be 100 nm.

Subsequently, the polymerizable liquid crystal composition (C1) was applied onto the obtained vertical alignment film using a bar coater and dried at 120° C. for 1 minute. (manufactured by Denki Co., Ltd.), the dye-containing layer 1 was formed by irradiating ultraviolet rays from the side to which the polymerizable liquid crystal composition (C1) was applied (in a nitrogen atmosphere, integrated light amount at a wavelength of 365 nm: 500 mJ/cm ² ). was formed to obtain a laminated structure (D1) having a layer structure of COP film/hard coat layer/vertical alignment film/dye-containing layer 1. When the thickness of the dye-containing layer 1 was measured with an ellipsometer (M-220 manufactured by JASCO Corporation), it was 0.6 μm.

(7) Absorbance measurement of dye-containing layer 1 Through a pressure-sensitive adhesive layer (manufactured by Lintec Co., Ltd.) having a thickness of 25 μm, the laminated structure (D1) obtained in (6) above, 4 cm long × 4 cm wide × thickness A sample for measurement was obtained by laminating with a glass of 0.7 mm. A sample for measurement was prepared so that the dye-containing layer 1 side of the laminated structure (D1) was on the glass side. The measurement sample is set in an ultraviolet-visible spectrophotometer ("UV-2450" manufactured by Shimadzu Corporation), and the maximum absorption wavelength (λmax) at a wavelength of 400 to 750 nm, the above formula (1) and formula (2) Absorbances AxC and AxC (z=60) were determined. The absorbance AxC was measured after correcting the absorbance of the measurement sample at a wavelength of 800 nm to be zero. AxC (z=60) was also measured after setting and tilting a measurement sample and correcting so that the absorbance at a wavelength of 800 nm was zero. The absorption maximum wavelength (λmax) at a wavelength of 400 to 750 nm is 598 nm, AxC is 0.005, AxC (z = 60) is 0.073, and AxC (z = 60)/AxC is 14.6. there were.

(8) Preparation of dye-containing layer 2 A dye-containing layer 2 was prepared in the same manner as the dye-containing layer 1 except that the bar coater was changed and the coating thickness of the polymerizable liquid crystal composition (C1) was changed. A laminate structure (D2) having a layer structure of film/hard coat layer/vertical alignment film/dye-containing layer 2 was obtained. When the thickness of the dye-containing layer 2 was measured with an ellipsometer (M-220 manufactured by JASCO Corporation), it was 1.2 μm.

(9) Absorbance Measurement of Dye-Containing Layer 2 The absorbance of the dye-containing layer 2 was measured in the same manner as the absorbance measurement of the dye-containing layer 1 . The absorption maximum wavelength (λmax) at a wavelength of 400 to 750 nm is 598 nm, AxC is 0.010, AxC (z = 60) is 0.15, and AxC (z = 60)/AxC is 15.0. there were.

(10) Preparation of polymerizable liquid crystal composition (C2) for forming dye-containing layer Except for changing the number of parts of dichroic dye A to 1.8 parts with respect to 100 parts of the mixture of polymerizable liquid crystal compounds A polymerizable liquid crystal composition (C2) for forming a dye-containing layer was obtained in the same manner as in the preparation of the polymerizable liquid crystal composition (C1).

(11) Preparation of dye-containing layer 3 A dye-containing layer 3 was formed in the same manner as the dye-containing layer 1 except that the polymerizable liquid crystal composition (C1) was changed to the polymerizable liquid crystal composition (C2). , a laminated structure (D3) having a layer structure of COP film/hard coat layer/vertical alignment film/dye-containing layer 3 was obtained. When the thickness of the dye-containing layer 3 was measured with an ellipsometer (M-220 manufactured by JASCO Corporation), it was 0.6 μm.

(12) Absorbance Measurement of Dye-Containing Layer 3 The absorbance of the dye-containing layer 3 was measured in the same manner as the absorbance measurement of the dye-containing layer 1 . The maximum absorption wavelength (λmax) at a wavelength of 400 to 750 nm is 598 nm, AxC is 0.010, AxC (z = 60) is 0.15, and AxC (z = 60)/AxC is 15.0. there were.

(13) Preparation of dye-containing layer 4 A dye-containing layer 4 was prepared in the same manner as the dye-containing layer 3 except that the bar coater was changed and the coating thickness of the polymerizable liquid crystal composition (C2) was changed. A laminate structure (D4) having a layer structure of film/hard coat layer/vertical alignment film/dye-containing layer 4 was obtained. When the thickness of the dye-containing layer 4 was measured with an ellipsometer (M-220 manufactured by JASCO Corporation), it was 1.2 μm.

(14) Absorbance Measurement of Dye-Containing Layer 4 The absorbance of the dye-containing layer 4 was measured in the same manner as the absorbance measurement of the dye-containing layer 1 . The maximum absorption wavelength (λmax) at a wavelength of 400 to 750 nm is 598 nm, AxC is 0.010, AxC (z = 60) is 0.28, and AxC (z = 60)/AxC is 28.0. there were.

(15) Preparation of water-based adhesive Dissolve 3 parts of carboxyl group-modified polyvinyl alcohol [trade name "KL-318" obtained from Kuraray Co., Ltd.] in 100 parts of water, and polyamide, which is a water-soluble epoxy resin, is dissolved in the aqueous solution. 1.5 parts of an epoxy additive [product name "Sumireze Resin (registered trademark) 650 (30)" obtained from Taoka Chemical Co., Ltd., aqueous solution with a solid concentration of 30%] was added to prepare a water-based adhesive. prepared.

(16) Preparation of UV-curable adhesive composition After mixing the cationic curable components a1 to a3 and the cationic polymerization initiator shown below, the cationic polymerization initiator and sensitizer shown below are further mixed to obtain The resulting mixture was defoamed to prepare an ultraviolet curable adhesive composition. In addition, the following compounding quantity is based on solid content.
- Cationic curable component a1 (70 parts):
3′,4′-epoxycyclohexylmethyl 3′,4′-epoxycyclohexane carboxylate (trade name: CEL2021P, manufactured by Daicel Corporation)
- Cationic curable component a2 (20 parts):
Neopentyl glycol diglycidyl ether (trade name: EX-211, manufactured by Nagase ChemteX Corporation)
- Cationic curable component a3 (10 parts):
2-ethylhexyl glycidyl ether (trade name: EX-121, manufactured by Nagase ChemteX Corporation)
- Cationic polymerization initiator (2.25 parts (solid content)):
Product name: 50% propylene carbonate solution of CPI-100 (manufactured by San-Apro Co., Ltd.) Sensitizer (2 parts):
1,4-diethoxynaphthalene

<Preparation of polarizing plate>
(17) Preparation of Polarizing Layer A 20 μm thick polyvinyl alcohol resin film was stretched and dyed with iodine to obtain a polarizing layer (8 μm thick) in which iodine was adsorbed and oriented on the polyvinyl alcohol resin film. The total draw ratio in this drawing was 5.2 times.

(18) Preparation of polarizing plate A hard coat cyclic olefin resin film (HC-COP film) in which a hard coat layer (HC layer) (thickness 3 µm) is formed on one side of a cyclic polyolefin resin film (COP film) (thickness 13 µm). 2) was prepared. This HC-COP film 2 had a pencil hardness of 5B on the HC layer side surface. The COP film side of this HC-COP film 2 (opposite side to the HC layer side) was attached to one surface of the polarizing layer obtained in (17) above via the water-based adhesive prepared in (15) above. combined. The in-plane retardation value Re (550) of this HC-COP film 2 at a wavelength of 550 nm is 0 (zero) nm, and an integrating sphere type light transmittance measuring device (“Haze Meter Hz-V3” manufactured by Suga Test Instruments Co., Ltd.) ) in accordance with JIS K7105, the total light transmittance Ht (%) was 0.1%.

When the optical characteristics were confirmed using a spectrophotometer (V7100, manufactured by JASCO Corp.) with the polarizing layer side of the polarizing plate as the incident surface, the luminosity correction single transmittance was 42.1%, and the luminosity correction polarization degree was 99.1%. 996%, -1.1 for single hue a, and 3.7 for single hue b.

<Preparation of optical laminate (manufacturing intermediate)>
[Example 1]
(Preparation of optical laminate (E1))
As a protective film provided with a hard coat layer, a hard coat cyclic olefin resin film (a hard coat layer (HC layer) (thickness: 3 μm) formed on one side of a cyclic polyolefin resin film (COP film) (thickness: 13 μm) (thickness: 3 μm). 16 μm thick) (hereinafter sometimes referred to as “16HC-COP film”) was prepared. This 16HC-COP film had a pencil hardness of 3B on the HC layer side surface. A protective film was attached to the hard coat layer side of the 16HC-COP film. The laminated structure ( D1) was laminated so that the dye-containing layer side was on the 16HC-COP film side. After that, from the laminated structure (D1) side (COP film side), an ultraviolet irradiation device with a belt conveyor (the lamp used is "H bulb" manufactured by Fusion UV Systems Co., Ltd.), and the irradiation intensity is 390 W / cm ² in the UVA region. UV rays are irradiated so that the integrated light amount is 420 mJ/cm ² , the UVB region is 400 mW/cm ² , and the integrated light amount is 400 mJ/cm ² to cure and bond the ultraviolet curable adhesive composition. An agent layer was formed to obtain a laminate. This laminate comprises a protective film/hard coat layer (pencil hardness of 3B)/COP film/adhesive layer (cured layer of UV-curable adhesive composition)/dye-containing layer 1/vertical alignment film/hard coat layer/ It has a layered structure of COP film. Subsequently, the COP film (ZF-14-50) of the obtained laminate was peeled off, and the exposed surface was covered with an adhesive layer (manufactured by Lintec, pressure-sensitive adhesive, 5 μm) via the above (18). The HC-COP film 2 side of the polarizing plate obtained in 1. was laminated.

Next, the laminate structure obtained in (4) above (A1 ) were laminated so that the horizontally aligned liquid crystal layer side was on the polarizing plate side, and the COP film (ZF-14-50) was peeled off to obtain an optical laminate (E1). At this time, they were laminated so that the angle between the absorption axis of the polarizing layer and the slow axis of the horizontally aligned liquid crystal layer was 45°. The layer structure of the optical laminate (E1) is: protective film/hard coat layer (pencil hardness 3B)/COP film/adhesive layer (cured product layer of UV-curable adhesive composition)/pigment-containing layer 1/vertical alignment Film / hard coat layer / adhesive layer / hard coat layer (pencil hardness 5B) / COP film / adhesive layer (cured layer of water-based adhesive) / polarizing layer / adhesive layer / horizontal alignment liquid crystal layer (retardation layer )/horizontal alignment film. The pressure-sensitive adhesive layer used in this optical laminate (E1) was measured using an integrating sphere light transmittance measuring device (“Haze Meter Hz-V3” manufactured by Suga Test Instruments Co., Ltd.) in accordance with JIS K7105. When the light transmittance Ht (%) was measured, it was 0.1%.

[Example 2]
(Preparation of optical laminate (E2))
The laminated structure (D1) was changed to the laminated structure (D2), the UV-curable adhesive composition was changed to an adhesive layer (manufactured by Lintec, pressure-sensitive adhesive, 5 μm), and the laminated structure ( An optical layered body (E2) was produced in the same manner as the optical layered body (E1), except that the ultraviolet irradiation after bonding with D2) was not performed. The layer structure of the optical laminate (E2) is protective film/hard coat layer (pencil hardness 3B)/COP film/adhesive layer/dye-containing layer 2/vertical alignment film/hard coat layer/adhesive layer/hard coat layer. (Pencil hardness 5B)/COP film/adhesive layer (hardened water-based adhesive layer)/polarizing layer/adhesive layer/horizontally aligned liquid crystal layer (retardation layer)/horizontally aligned film. All of the pressure-sensitive adhesive layers used in this optical laminate (E2) were measured in accordance with JIS K7105 using an integrating sphere light transmittance measuring device (“Haze Meter Hz-V3” manufactured by Suga Test Instruments Co., Ltd.). , the total light transmittance Ht (%) was 0.1%.

[Examples 3 to 5]
Optical laminates (E3) to (E5) were produced in the same manner as the optical laminate (E1) except that the laminate structure (D1) was changed to the laminate structures (D2) to (D4). .

<Preparation of Vertically Aligned Liquid Crystal Layer>
(19) Preparation of vertically aligned liquid crystal layer 1 0.1 part of F-556 as a leveling agent and Irgacure 369 as a polymerization initiator are added to 100 parts of a polymerizable liquid crystal compound Paliocolor LC242 (registered trademark of BASF). Added 3 parts. Cyclopentanone was added so that the solid content concentration was 13% to obtain a polymerizable liquid crystal composition (C3). Next, in the same manner as in the preparation of the dye-containing layer 1 described in (6) above, except that the polymerizable liquid crystal composition (C3) was used, a vertical alignment layer was formed on the vertical alignment film formed on the hard coat layer. A liquid crystal layer 1 was formed to obtain a laminate structure (D5).

(20) Measurement of Retardation in Thickness Direction of Vertically Aligned Liquid Crystal Layer 1 In order to confirm the alignment state of the polymerizable liquid crystal compound in the vertically aligned liquid crystal layer 1, Oji measurement was performed after confirming that there was no retardation in the COP film. Using KOBRA-WPR manufactured by Kiki Co., Ltd., the thickness direction retardation value of the laminated structure (D5) was measured as the thickness direction retardation value RthC of the vertically aligned liquid crystal layer 1 . In addition, since the retardation of a film having anisotropic absorption in visible light cannot be measured with the above measuring equipment, the RthC (λ) of the vertically aligned liquid crystal cured film excluding the dichroic dye is measured as a reference. did. In the measurement, the incident angle of light to the laminated structure (D5) was changed, and the front retardation value of the vertically aligned liquid crystal layer 1 and the retardation value when tilted 40° around the fast axis were measured. It was measured. The average refractive index at each wavelength was measured using an ellipsometer M-220 manufactured by JASCO Corporation. The thickness of the vertically aligned liquid crystal layer 1 was measured using an Optical NanoGauge film thickness gauge C12562-01 manufactured by Hamamatsu Photonics K.K. From the front retardation value measured above, the retardation value when tilted 40 ° around the fast axis, the average refractive index, and the thickness value of the vertically aligned liquid crystal layer 1, Oji Scientific Instruments technical data (http: / /www.oji-keisoku.co.jp/products/kobra/reference.html) was used as a reference to calculate the three-dimensional refractive index. From the obtained three-dimensional refractive index, the retardation value RthC(λ) in the thickness direction of the vertically aligned liquid crystal layer 1 was calculated according to the above equation (7). As a result, RthC(550) was −70 nm and RthC(450)/RthC(550) was 1.10.

(21) Fabrication of vertically aligned liquid crystal layer 2 A vertically aligned liquid crystal layer 2 was prepared in the same manner as the vertically aligned liquid crystal layer 1 except that the bar coater was changed and the coating thickness of the polymerizable liquid crystal composition (C3) was changed. was formed to obtain a laminated structure (D6).

(22) Measurement of Retardation in the Thickness Direction of the Vertically Aligned Liquid Crystal Layer 2 In the same manner as the measurement of the retardation in the thickness direction of the vertically aligned liquid crystal layer 1, the retardation value RthC(λ) in the thickness direction of the vertically aligned liquid crystal layer 2 was measured. Calculated. As a result, RthC(550) was −140 nm and RthC(450)/RthC(550) was 1.10.

<Preparation of optical laminate>
[Example 6]
(Production of optical laminate (F1))
An adhesive layer (thickness: 2 μm ), the laminated structure (D5) prepared in (19) above was laminated so that the vertically aligned liquid crystal layer 1 side was on the optical laminated body (E1) side. After that, from the laminated structure (D5) side (COP film side), an ultraviolet irradiation device with a belt conveyor (the lamp used is “H bulb” manufactured by Fusion UV Systems Co., Ltd.), and the irradiation intensity in the UVA region is 390 W / cm ² UV rays are irradiated so that the integrated light amount is 420 mJ/cm ² , the UVB region is 400 mW/cm ² , and the integrated light amount is 400 mJ/cm ² to cure and bond the ultraviolet curable adhesive composition. An agent layer was formed, and the COP film (ZF-14-50) was peeled off to obtain an optical laminate (F1). The layer structure of the optical laminate (F1) is: protective film/hard coat layer (pencil hardness 3B)/COP film/adhesive layer (cured layer of UV-curable adhesive composition)/pigment-containing layer 1/vertical alignment Film / hard coat layer / adhesive layer / hard coat layer (pencil hardness 5B) / COP film / adhesive layer (cured layer of water-based adhesive) / polarizing layer / adhesive layer / horizontal alignment liquid crystal layer (retardation layer )/horizontal alignment film/adhesive layer (cured product layer of ultraviolet curable adhesive composition)/vertical alignment liquid crystal layer 1/vertical alignment film/hard coat layer.

(Preparation of optical laminate (G1) with adhesive layer)
An adhesive layer (manufactured by Lintec Corporation, pressure-sensitive adhesive, 25 μm) is attached to the vertically aligned liquid crystal layer side of the laminated structure (D5) of the optical laminate (F1) to form an optical laminate with an adhesive layer ( G1) was obtained. The layer structure of the adhesive layer-attached optical laminate (G1) is: protective film/hard coat layer (pencil hardness 3B)/COP film/adhesive layer (cured product layer of UV-curable adhesive composition)/pigment-containing layer. 1/vertical alignment film/hard coat layer/adhesive layer/hard coat layer (pencil hardness 5B)/COP film/adhesive layer (cured water-based adhesive layer)/polarizing layer/adhesive layer/horizontally aligned liquid crystal layer (retardation layer)/horizontal alignment film/adhesive layer (cured product layer of UV-curable adhesive composition)/vertical alignment liquid crystal layer 1/vertical alignment film/hard coat layer/adhesive layer.

[Examples 7 to 9]
Optical layered body (F1) and adhesive layer-attached optical layered body (G1 ), optical laminates (F2) to (F4) and adhesive layer-attached optical laminates (G2) to (G4) were produced.

[Example 10]
Optical laminate (F2) and optical with adhesive layer except that the laminate structure (D5) used for laminating the vertically aligned liquid crystal layer was changed to the laminate structure (D6) prepared in (21) above. An optical laminate (F5) and an optical laminate with an adhesive layer (G5) were produced in the same manner as the laminate (G2).

[Example 11]
Except that the optical layered body (E1) was changed to the optical layered body (E2) obtained in Example 2, in the same manner as the optical layered body (F2) and the adhesive layer-attached optical layered body (G2), An optical laminate (F6) and an optical laminate with an adhesive layer (G6) were produced.

[Comparative Example 1]
(Production of optical laminate (F7))
A protective film is attached to the hard coat layer side of the 16HC-COP film of the polarizing plate prepared in (18) above, and an adhesive layer (manufactured by Lintec, pressure-sensitive adhesive, 5 μm) is placed on the polarizing layer side. , The laminated structure (A1) obtained in (4) above is laminated so that the horizontally aligned liquid crystal layer side faces the polarizing plate side, and the COP film (ZF-14-50) is peeled off to obtain an optical laminated body (E6 ). The layer structure of the optical laminate (E6) is a protective film/hard coat layer (pencil hardness of 5B)/COP film/adhesive layer (cured water-based adhesive layer)/polarizing layer/adhesive layer/horizontally aligned liquid crystal layer. (retardation layer)/horizontal alignment film. The pressure-sensitive adhesive layer used in this optical laminate (E6) was measured in accordance with JIS K7105 using an integrating sphere light transmittance measuring device (“Haze Meter Hz-V3” manufactured by Suga Test Instruments Co., Ltd.). When the light transmittance Ht (%) was measured, it was 0.1%.

On the horizontal alignment film side of the laminated structure (A1) of the optical laminate (E6) obtained above, an adhesive layer (manufactured by Lintec Corporation, pressure-sensitive adhesive, 5 μm) was interposed, and prepared in the above (6). The laminate structure (D1) was laminated so that the dye-containing layer 1 side was on the optical laminate (E1) side, and the COP film was peeled off to obtain an optical laminate (F7). The layer structure of the optical laminate (F7) is a protective film/hard coat layer (pencil hardness 5B)/COP film/adhesive layer (cured water-based adhesive layer)/polarizing layer/adhesive layer/horizontally aligned liquid crystal layer. (retardation layer)/horizontal alignment film/adhesive layer/dye-containing layer 1/vertical alignment film/hard coat layer.

The thickness direction retardation value RthC(λ) of the dye-containing layer 1 was calculated in the same manner as the measurement of the thickness direction retardation of the vertically aligned liquid crystal layer 1 . As a result, RthC(550) was −70 nm and RthC(450)/RthC(550) was 1.10.

(Preparation of optical layered body (G7) with adhesive layer)
An adhesive layer (manufactured by Lintec Corporation, pressure-sensitive adhesive, 25 μm) is attached to the vertically aligned liquid crystal layer side of the laminated structure (D1) of the optical laminate (F7) to form an optical laminate with an adhesive layer ( G7) was obtained. The layer structure of the adhesive layer-attached optical laminate (G7) is: protective film/hard coat layer (pencil hardness 5B)/COP film/adhesive layer (cured water-based adhesive layer)/polarizing layer/adhesive layer/ Horizontal alignment liquid crystal layer (retardation layer)/horizontal alignment film/adhesive layer/dye-containing layer 1/vertical alignment film/hard coat layer/adhesive layer.

[Comparative Example 2]
Optical layered body (F7) and adhesive layer-attached optical layered body (G7) were prepared in the same manner as the optical layered body (F7) except that the layered structure (D1) was changed to the layered structure (D2) prepared in (8) above. , an optical laminate (F8) and an optical laminate with an adhesive layer (G8) were produced.

The thickness direction retardation value RthC(λ) of the dye-containing layer 2 was calculated in the same manner as the measurement of the thickness direction retardation of the vertically aligned liquid crystal layer 1 . As a result, RthC(550) was −140 nm and RthC(450)/RthC(550) was 1.10.

[Comparative Example 3]
Optical layered body (F7) and adhesive layer-attached optical layered body (G7) were prepared in the same manner as the optical layered body (F7) except that the layered structure (D1) was changed to the layered structure (D5) prepared in (19) above. , an optical laminate (F9) and an optical laminate with an adhesive layer (G9) were produced.

<Evaluation>
(Evaluation of initial optical laminate with adhesive layer)
The front glass and the polarizing plate were removed from "Galaxy S5" manufactured by SAMSUNG, and the display device was taken out. The pressure-sensitive adhesive layer side of the pressure-sensitive adhesive layer-attached optical layered body produced by the above method was bonded, and the protective film was peeled off. After that, with the power source of the display device turned off (during black display), the reflected hue was observed when viewed from the front direction and oblique direction, and evaluated according to the evaluation criteria shown below. The results are shown in Tables 1 and 2.
[Evaluation criteria]
A: No color is felt B: Color is slightly felt C: Color is felt D: More color is felt

Next, using the same sample, turn on the power of the display device to maximize the brightness, turn off all the settings that change the screen display color such as the blue light cut function and color balance change, and display the white screen ( When white is displayed) (when the HTML color code #FFFFFF is displayed), the hue when viewed from the front direction and oblique direction was confirmed and evaluated according to the evaluation criteria described above.

(Evaluation of optical laminate with pressure-sensitive adhesive layer after heat resistance test)
The pressure-sensitive adhesive layer-attached optical layered body prepared by the above method was put into an oven set at a temperature of 80° C., and a heat resistance test was performed by holding the oven for 240 hours. The pressure-sensitive adhesive layer-attached optical layered body after the heat resistance test was evaluated in the same procedure as the initial evaluation of the pressure-sensitive adhesive layer-attached optical layered body. The results are shown in Tables 1 and 2.

1 optical laminate, 5 to 7 optical laminate, 11 dye-containing layer, 12 polarizing layer, 13 retardation layer, 15 protective film (first protective film), 16 hard coat layer (first hard coat layer), 17 vertical Oriented liquid crystal layer 20 First laminate 152 First protective film 162 Second hard coat layer.

Claims (16)

An optical laminate comprising a dye-containing layer, a polarizing layer, and a retardation layer having an in-plane retardation in this order,
The dye-containing layer is
Containing a dichroic dye having a maximum absorption in the wavelength range of 400 nm or more and 750 nm or less,
An optical laminate that satisfies the relationships of the following formulas (1) and (2).
0.001≤AxC≤0.3 (1)
AxC(z=60)/AxC>2 (2)
[In formulas (1) and (2),
AxC is the absorbance of the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer, and represents the absorbance of linearly polarized light vibrating in the x-axis direction,
AxC (z = 60) is the absorbance at the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer, and the x when the dye-containing layer is rotated by 60° with the y axis as the rotation axis. represents the absorbance of linearly polarized light oscillating in the axial direction,
The x-axis represents an arbitrary direction in the plane of the dye-containing layer, and the y-axis represents a direction perpendicular to the x-axis in the plane of the dye-containing layer. ] An intermediate for producing a laminate comprising, in this order, the dye-containing layer, the polarizing layer, the retardation layer, and a vertically aligned liquid crystal layer cured in a state in which the polymerizable liquid crystal compound is aligned in the lamination direction of the optical laminate, in this order. The optical laminate according to claim 1, wherein An optical laminate comprising, in this order, a dye-containing layer, a polarizing layer, a retardation layer having an in-plane retardation, and a vertically aligned liquid crystal layer,
The vertically aligned liquid crystal layer is a cured product layer cured in a state in which the polymerizable liquid crystal compound is oriented in the lamination direction of the optical laminate,
The dye-containing layer is
Containing a dichroic dye having a maximum absorption between wavelengths of 400 nm and 750 nm,
An optical laminate that satisfies the relationships of the following formulas (1) and (2).
0.001≤AxC≤0.3 (1)
AxC(z=60)/AxC>2 (2)
[In formulas (1) and (2),
AxC is the absorbance of the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer, and represents the absorbance of linearly polarized light vibrating in the x-axis direction,
AxC (z = 60) is the absorbance at the absorption maximum wavelength in the wavelength range of 400 nm or more and 750 nm or less of the dye-containing layer, and the x when the dye-containing layer is rotated by 60° with the y axis as the rotation axis. represents the absorbance of linearly polarized light oscillating in the axial direction,
The x-axis represents an arbitrary direction in the plane of the dye-containing layer, and the y-axis represents a direction perpendicular to the x-axis in the plane of the dye-containing layer. ] The optical layered product according to any one of claims 1 to 3, wherein the dye-containing layer further includes a cured product obtained by curing the polymerizable liquid crystal compound in a state of being oriented in the layering direction of the optical layered product. The optical system according to any one of claims 1 to 4, wherein the retardation layer is a horizontally aligned liquid crystal layer cured in a state in which the polymerizable liquid crystal compound is aligned in a direction orthogonal to the lamination direction of the optical laminate. laminate. The optical laminate according to any one of claims 1 to 5, wherein the retardation layer satisfies the relationship of formula (3) below.
ReA(450)/ReA(550)<1.00 (3)
[In formula (3), ReA(450) and ReA(550) represent in-plane retardation values of the retardation layer at wavelengths of 450 nm and 550 nm, respectively. ] The optical laminate according to any one of claims 1 to 6, wherein the retardation layer satisfies the relationship of formula (4) below.
120 nm≦ReA(550)≦170 nm (4)
[In formula (4), ReA(550) represents an in-plane retardation value of the retardation layer at a wavelength of 550 nm. ] The optical laminate according to any one of claims 1 to 7, wherein an angle between the absorption axis of the polarizing layer and the slow axis of the retardation layer is within the range of 45°±5°. The optical laminate according to any one of claims 1 to 8, wherein the dichroic dye is an azo dye. The optical laminate according to any one of claims 1 to 9, wherein the dye-containing layer satisfies any one of the following [a1] to [a3].
[a1] having maximum absorption in both the wavelength range of 400 nm or more and less than 550 nm and the wavelength range of 550 nm or more and less than 7000 nm;
[a2] has a maximum absorption in a wavelength range of 400 nm or more and less than 550 nm, and does not have a maximum absorption in a wavelength range of 550 nm or more and 700 nm or less;
[a3] It has no maximum absorption in the wavelength range of 400 nm or more and less than 550 nm, but has maximum absorption in the wavelength range of 550 nm or more and 700 nm or less. The optical laminate according to any one of claims 1 to 10, further comprising a hard coat layer on a side of the dye-containing layer opposite to the polarizing layer. The optical laminate according to any one of claims 1 to 11, further comprising a protective film on a side of the dye-containing layer opposite to the polarizing layer. Further, an adhesive layer is provided between the retardation layer and the vertically aligned liquid crystal layer,
The optical laminate according to any one of claims 1 to 12, wherein the adhesive layer is in direct contact with the retardation layer and the vertically aligned liquid crystal layer. 14. The optical laminate according to claim 13, wherein the adhesive layer is a cured product layer of an ultraviolet curable adhesive composition. An optical laminate according to any one of claims 1 to 14,
In the display device, the optical layered body is arranged such that the dye-containing layer is located on the viewing side of the polarizing layer. 16. The display device according to claim 15, which is an organic EL display device.

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