WO2024071162A1

WO2024071162A1 - Optically anisotropic laminate and optical element

Info

Publication number: WO2024071162A1
Application number: PCT/JP2023/035064
Authority: WO
Inventors: 祥貢光田; 輝恒大澤; 淳一大泉
Original assignee: 三菱ケミカル株式会社
Priority date: 2022-09-27
Filing date: 2023-09-27
Publication date: 2024-04-04

Abstract

Provided is an optically anisotropic laminate in which a protective layer is laminated on an anisotropic pigment layer. The anisotropic pigment layer is a layer formed from an anisotropic pigment film formation composition that contains a pigment, a polymerizable liquid crystal compound, and a photopolymerization initiator. Provided is an optically anisotropic laminate in which the absolute value of the surface free energy difference between the anisotropic pigment layer and the protective layer is 3 mN/m2 or greater. Alternatively, there is provided an optically anisotropic laminate in which the surface free energy of a film obtained by curing a curable resin is 45 mN/m2 or less. Alternatively, there is provided an optically anisotropic laminate in which the protective layer is formed from a protective layer formation composition that contains a photocurable resin, and the photocurable resin includes a photocurable silicone resin.

Description

Optically anisotropic laminate and optical element

The present invention relates to an optically anisotropic laminate and optical element that exhibits high dichroism and is useful for linear polarizing films, circular polarizing films, etc., provided in display elements such as light control elements, liquid crystal elements (LCDs), and organic electroluminescence elements (OLEDs).

In LCDs, linear and circular polarizing films are used to control the optical rotation and birefringence of the display. Circular polarizing films are also used in OLEDs to prevent reflection of external light in bright places.

Conventionally, examples of such polarizing films include a polarizing film made of polyvinyl alcohol (PVA) dyed with low concentration of iodine (iodine-PVA polarizing film) (Patent Document 1).
However, iodine-PVA polarizing films dyed with low concentrations of iodine have problems such as changes in color due to sublimation or deterioration of iodine depending on the usage environment, and warping due to relaxation of the stretching of PVA.

It is also known that an anisotropic dye film formed by coating a liquid crystal composition containing a dye functions as a polarizing film (Patent Document 2).
In this case, an optically anisotropic laminate is formed by laminating a protective layer on the anisotropic dye layer.

Japanese Patent Application Laid-Open No. 1-105204 JP 2004-535483 A

When an optically anisotropic laminate consisting of an anisotropic dye layer and a protective layer is used as a polarizer, there is an issue that the appearance and performance of the polarizer deteriorates under heating conditions.

The present invention aims to provide an optically anisotropic laminate in which an anisotropic dye layer and a protective layer are laminated, which suppresses deterioration of appearance and performance under heating conditions and maintains good appearance and performance, and an optical element.

The present inventors have discovered that by setting the absolute value of the surface free energy difference between the anisotropic dye layer and the protective layer to a predetermined value or more, it is possible to suppress compatibility between the anisotropic dye layer and the protective layer, and to provide an optically anisotropic laminate that exhibits good heat resistance without mixing between the two layers even in a heated environment, and that is excellent in solvent resistance, appearance, and performance.
The gist of the first aspect of the present invention is as follows.

[1-1] An optically anisotropic laminate in which a protective layer is laminated on an anisotropic dye layer,
the anisotropic dye layer is a layer formed from a composition for forming an anisotropic dye film, which contains a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator;
An optically anisotropic laminate, wherein the absolute value of the difference in surface free energy between the anisotropic dye layer and the protective layer is 3 mN/ ^m2 or more.

[1-2] The optically anisotropic laminate described in [1-1], wherein the protective layer is a layer formed from a protective layer-forming composition containing a photocurable silicone resin.

[1-3] The optically anisotropic laminate according to [1-2], in which the photocurable silicone resin contains fluorine atoms.

[1-4] An optically anisotropic laminate according to any one of [1-1] to [1-3], in which the polymerizable liquid crystal compound is a low molecular weight polymerizable liquid crystal compound that does not have a repeating structure.

[1-5] The optically anisotropic laminate according to any one of [1-1] to [1-4], wherein the polymerizable liquid crystal compound is a compound represented by the following formula (1):
Q ¹ -R ¹ -A ¹¹ -Y ¹ -A ¹² -(Y ² -A ¹³ ) _k -R ² -Q ² ... (1)
(In formula (1),
^-Q1 represents a hydrogen atom or a polymerizable group;
^-Q2 represents a polymerizable group;
-R ¹ - and -R ² - each independently represent a chain organic group;
-A ¹¹ - and -A ¹³ - each independently represent a partial structure represented by the following formula (2), a divalent organic group, or a single bond;
-A ¹² - represents a partial structure represented by the following formula (2) or a divalent organic group;
Each of -Y ¹ - and -Y ² - independently represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C≡C-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -;
One of -A ¹¹ - and -A ¹³ - is a partial structure represented by the following formula (2) or a divalent organic group:
k is 1 or 2.
When k is 2, two -Y ² -A ¹³ - may be the same or different.
-Cy-X ² -C≡C-X ¹ - ... (2)
(In formula (2),
-Cy- represents a hydrocarbon ring group or a heterocyclic group;
-X ¹ - represents -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -;
-X ² - represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -.

[1-6] An optical element having an optically anisotropic laminate according to any one of [1-1] to [1-5].

The present inventors have discovered that by setting the surface free energy of a film obtained by curing a curable resin contained in a composition for forming a protective layer to a predetermined value or less, it is possible to suppress compatibility between the anisotropic dye layer and the protective layer, and provide an optically anisotropic laminate that exhibits good heat resistance without mixing between the two layers even in a heated environment, and that also has excellent solvent resistance, appearance, and performance.
The second aspect of the present invention is as follows.

[2-1] An optically anisotropic laminate in which a protective layer is laminated on an anisotropic dye layer,
the anisotropic dye layer is a layer formed from a composition for forming an anisotropic dye film, which contains a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator;
the protective layer is a layer formed from a protective layer-forming composition containing a curable resin,
An optically anisotropic laminate, wherein the surface free energy of a film obtained by curing the curable resin is 45 mN/ ^m2 or less.

[2-2] The optically anisotropic laminate described in [2-1], wherein the curable resin is a photocurable silicone resin.

[2-3] The optically anisotropic laminate according to [2-2], in which the photocurable silicone resin contains fluorine atoms.

[2-4] An optically anisotropic laminate according to any one of [2-1] to [2-3], in which the polymerizable liquid crystal compound is a low molecular weight polymerizable liquid crystal compound that does not have a repeating structure.

[2-5] The optically anisotropic laminate according to any one of [2-1] to [2-4], wherein the polymerizable liquid crystal compound is a compound represented by the following formula (1):
Q ¹ -R ¹ -A ¹¹ -Y ¹ -A ¹² -(Y ² -A ¹³ ) _k -R ² -Q ² ... (1)
(In formula (1),
^-Q1 represents a hydrogen atom or a polymerizable group;
^-Q2 represents a polymerizable group;
-R ¹ - and -R ² - each independently represent a chain organic group;
-A ¹¹ - and -A ¹³ - each independently represent a partial structure represented by the following formula (2), a divalent organic group, or a single bond;
-A ¹² - represents a partial structure represented by the following formula (2) or a divalent organic group;
Each of -Y ¹ - and -Y ² - independently represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C≡C-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -;
One of -A ¹¹ - and -A ¹³ - is a partial structure represented by the following formula (2) or a divalent organic group:
k is 1 or 2.
When k is 2, two -Y ² -A ¹³ - may be the same or different.
-Cy-X ² -C≡C-X ¹ - ... (2)
(In formula (2),
-Cy- represents a hydrocarbon ring group or a heterocyclic group;
-X ¹ - represents -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -;
-X ² - represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -.

[2-6] An optical element having an optically anisotropic laminate according to any one of [2-1] to [2-5].

The present inventors have discovered that by forming a protective layer from a composition for forming a protective layer containing a photocurable resin and using a photocurable silicone resin as the photocurable resin, it is possible to suppress compatibility between the anisotropic dye layer and the protective layer, and to provide an optically anisotropic laminate that exhibits good heat resistance without mixing between the two layers even in a heated environment, and that is excellent in solvent resistance, appearance, and performance.
The third aspect of the present invention is as follows.

[3-1] An optically anisotropic laminate in which a protective layer is laminated on an anisotropic dye layer,
the anisotropic dye layer is a layer formed from a composition for forming an anisotropic dye film, which contains a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator;
the protective layer is a layer formed from a protective layer-forming composition containing a photocurable resin,
The optically anisotropic laminate, wherein the photocurable resin comprises a photocurable silicone resin.

[3-2] The optically anisotropic laminate according to [3-1], in which the molecular weight M of the photocurable silicone resin is 5000 or more.

[3-3] An optically anisotropic laminate according to any one of [3-1] to [3-2], in which the photocurable silicone resin has fluorine atoms.

[3-4] An optically anisotropic laminate according to any one of [3-1] to [3-3], in which the polymerizable liquid crystal compound is a low molecular weight polymerizable liquid crystal compound that does not have a repeating structure.

[3-5] The optically anisotropic laminate according to any one of [3-1] to [3-4], wherein the polymerizable liquid crystal compound is a compound represented by the following formula (1):
Q ¹ -R ¹ -A ¹¹ -Y ¹ -A ¹² -(Y ² -A ¹³ ) _k -R ² -Q ² ... (1)
(In formula (1),
^-Q1 represents a hydrogen atom or a polymerizable group;
^-Q2 represents a polymerizable group;
-R ¹ - and -R ² - each independently represent a chain organic group;
-A ¹¹ - and -A ¹³ - each independently represent a partial structure represented by the following formula (2), a divalent organic group, or a single bond;
-A ¹² - represents a partial structure represented by the following formula (2) or a divalent organic group;
Each of -Y ¹ - and -Y ² - independently represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C≡C-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -;
One of -A ¹¹ - and -A ¹³ - is a partial structure represented by the following formula (2) or a divalent organic group:
k is 1 or 2.
When k is 2, two -Y ² -A ¹³ - may be the same or different.
-Cy-X ² -C≡C-X ¹ - ... (2)
(In formula (2),
-Cy- represents a hydrocarbon ring group or a heterocyclic group;
-X ¹ - represents -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -;
-X ² - represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -.

[3-6] An optical element having an optically anisotropic laminate according to any one of [3-1] to [3-5].

The optically anisotropic laminate of the present invention is excellent in heat resistance and solvent resistance, and can maintain a good appearance and a high degree of polarization when used as a polarizer.
The optical element of the present invention contains such an optically anisotropic laminate of the present invention, and therefore can maintain excellent optical performance.

The following is a detailed description of an embodiment of the present invention. The present invention is not limited to the following embodiment, and can be modified in various ways within the scope of the invention.

[Optical anisotropic laminate]
The optically anisotropic laminate of the first invention of the present invention is an optically anisotropic laminate in which a protective layer (hereinafter, may be referred to as the "protective layer of the first invention") is laminated on an anisotropic dye layer (hereinafter, may be referred to as the "anisotropic dye film of the present invention" or simply as the "anisotropic dye film"), the anisotropic dye layer is a layer formed from a composition for forming an anisotropic dye film containing a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator, and is characterized in that the absolute value of the surface free energy difference between the anisotropic dye layer and the protective layer is 3 mN/ ^m2 or more.

The optically anisotropic laminate of the second invention of the present invention is an optically anisotropic laminate in which a protective layer (hereinafter, may be referred to as the "protective layer of the second invention") is laminated on an anisotropic dye layer (hereinafter, may be referred to as the "anisotropic dye film of the present invention" or simply as the "anisotropic dye film"), the anisotropic dye layer is a layer formed from an anisotropic dye film-forming composition containing a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator, the protective layer is a layer formed from a protective layer-forming composition containing a curable resin (hereinafter, may be referred to as the "protective layer-forming composition of the second invention"), and the surface free energy of the film obtained by curing the curable resin is 32 mN/ ^m2 or less.

The optically anisotropic laminate of the third invention of the present invention is an optically anisotropic laminate in which a protective layer (hereinafter, sometimes referred to as the "protective layer of the third invention") is laminated on an anisotropic dye layer (hereinafter, sometimes referred to as the "anisotropic dye film of the present invention" or simply as the "anisotropic dye film"), the anisotropic dye layer is a layer formed from a composition for forming an anisotropic dye film containing a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator, the protective layer is a layer formed from a composition for forming a protective layer containing a photocurable resin, and the photocurable resin is a photocurable silicone resin.

Hereinafter, the "optically anisotropic laminate of the first invention", the "optically anisotropic laminate of the second invention" and the "optically anisotropic laminate of the third invention" will be collectively referred to as the "optically anisotropic laminate of the present invention".
Moreover, the "protective layer of the first invention", the "protective layer of the second invention" and the "protective layer of the third invention" are collectively referred to as the "protective layer of the present invention".

The anisotropic dye film referred to in this invention is a dye film that has anisotropy in electromagnetic properties in any two directions selected from a total of three directions in a three-dimensional coordinate system, the thickness direction of the anisotropic dye film and any two orthogonal in-plane directions. Examples of electromagnetic properties include optical properties such as absorption and refraction, and electrical properties such as resistance and capacitance.

The protective layer referred to in the present invention is a layer for imparting functionality such as abrasion resistance, scratch resistance, stress relaxation resistance, chemical resistance, gas resistance, water resistance, and corrosion resistance, as well as preventing bleeding, flattening, making the surface easier to adhere, releasing the surface, and adjusting optical properties. The protective layer may be made of a photocurable film or may be a layer that does not have polymerizability, but is preferably a photocurable film.

The total thickness (overall thickness) of the optically anisotropic laminate of the present invention is preferably 0.5 μm or more, more preferably 1 μm or more, and even more preferably 1.5 μm or more. On the other hand, the total thickness (overall thickness) of the optically anisotropic laminate of the present invention is preferably 800 μm or less, more preferably 500 μm or less, and even more preferably 300 μm or less. When the total thickness of the optically anisotropic laminate of the present invention is equal to or more than the above lower limit, it becomes easy to handle, and when it is equal to or less than the above upper limit, it tends to be thinner and lighter when used as an optical element.

The optically anisotropic laminate of the present invention having an anisotropic dye layer and a protective layer may be laminated with a photocurable film or a functional film that does not have photopolymerizability other than the anisotropic dye layer and the protective layer. Examples of other functional films include adhesive films having tackiness and/or adhesion, anti-reflection films, retardation films, light control films that absorb, reflect or scatter light, low refractive films, high refractive films, electrically insulating films, electrically conductive films, alignment films, release films, etc.

In the optically anisotropic laminate of the present invention, the anisotropic dye layer is usually produced by irradiating an active energy ray to a film formed by wet film formation of a composition for forming an anisotropic dye film containing a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator, as described below (hereinafter, sometimes referred to as the "composition for forming an anisotropic dye film of the present invention").

The polymerizable liquid crystal compound in the composition for forming an anisotropic dye film is at least partially polymerized during the manufacturing process of the anisotropic dye film, and becomes a polymer of the polymerizable liquid crystal compound and is present in the anisotropic dye film.

In the optically anisotropic laminates of the first and second inventions, the protective layer is preferably a layer formed from a protective layer-forming composition containing a photocurable silicone resin described below (hereinafter, sometimes referred to as the "protective layer-forming composition of the present invention").
In the optically anisotropic laminate of the third invention, the protective layer is usually a layer formed from a protective layer-forming composition containing a photocurable silicone resin described below, that is, the protective layer-forming composition of the present invention.

[Characteristics of the optically anisotropic laminate of the first invention]
The optically anisotropic laminate of the first invention is characterized in that the absolute value of the surface free energy difference between the anisotropic dye layer of the present invention and the protective layer of the first invention is 3 mN/m ² or more. If the absolute value of the surface free energy difference is 3 mN/m ² or more, the heat resistance and solvent resistance are excellent, and the appearance and performance as a polarizer or the like can be stably maintained.
In other words, a large absolute value of the difference in surface free energy between the anisotropic dye layer and the protective layer means that the anisotropic dye layer and the protective layer have low compatibility, and the low compatibility makes it difficult for the two layers to mix even when heated or exposed to a solvent, resulting in good heat resistance and solvent resistance.
From this viewpoint, the absolute value of the surface free energy difference between the anisotropic dye layer of the present invention and the protective layer of the first invention is preferably 5 mN/ ^m2 or more, more preferably 8 mN/ ^m2 or more, and even more preferably 12 mN/m2 or ^more .
There is no particular upper limit to the absolute value of this surface free energy difference, but it is usually 60 mN/ ^m2 or less due to the influence of intermolecular interactions, etc.

The following methods (1) and/or (2) can be used to set the absolute value of the difference in surface free energy between the anisotropic dye layer of the present invention and the protective layer of the first invention to the above lower limit or more.
(1) Reducing the surface free energy of the protective layer In order to reduce the surface energy of the protective layer, the protective layer-forming composition of the present invention containing a photocurable silicone resin described below, particularly a photocurable silicone resin having fluorine atoms, is used as the photocurable resin, thereby suppressing intermolecular interactions and reducing the dispersion component of the surface free energy, thereby making it possible to reduce the surface energy of the protective layer.
(2) Increasing the surface free energy of the anisotropic dye layer In order to increase the surface free energy of the anisotropic dye layer, there can be mentioned a method of adjusting the structure of the polymerizable liquid crystal compound or an additive such as a leveling agent.

The surface free energy of the anisotropic dye layer formed using the anisotropic dye film-forming composition suitable for the present invention described below is usually about 20 to 50 mN/m ² , preferably 30 to 40 mN/m ^2. The surface free energy of the protective layer formed using the protective layer-forming composition suitable for the present invention described below is usually about 15 to 45 mN/m ² , preferably 20 to 35 mN/m ^2. Therefore, the surface free energy of the anisotropic dye layer of the present invention is preferably about 3 to 30 mN/m ² higher than the surface free energy of the protective layer of the first invention.

In the first invention, the surface free energy is measured for the cured anisotropic dye film surface and the protective layer surface, respectively, by the method described in the Examples section below.

[Characteristics of the optically anisotropic laminate of the second invention]
The optically anisotropic laminate of the second invention is characterized in that it comprises a protective layer formed from a protective layer-forming composition containing a curable resin, and the surface free energy of the film obtained by curing the curable resin is 45 mN/m ² or less. By comprising a protective layer formed from a protective layer-forming composition containing a curable resin, and the surface free energy of the film obtained by curing the curable resin is 45 mN/m ² or less, it is possible to stably maintain the appearance and performance as a polarizer or the like, with excellent heat resistance and solvent resistance.

In other words, for the curable resin contained in the composition for forming a protective layer, the small surface free energy of the film obtained by curing the curable resin means that the film tends to have low wettability to other substances, and the low affinity with the anisotropic dye film as another substance means that the two layers are less likely to mix even when exposed to heat or solvent, resulting in good heat resistance and solvent resistance.
From this viewpoint, for the curable resin contained in the protective layer forming composition of the second invention, the surface free energy of the film obtained by curing the curable resin is 45 mN / m ² or less, preferably 40 mN / m ² or less, more preferably 35 mN / m ² or less, and even more preferably 30 mN / m ² or less. For the curable resin contained in the protective layer forming composition of the second invention, there is no particular restriction on the lower limit of the surface free energy of the film obtained by curing the curable resin, but in order to laminate another layer on the protective layer, it is preferably 10 mN / m ² or more, more preferably 15 mN / m ² or more, and even more preferably 18 mN / m ² or more.

Regarding the curable resin contained in the protective layer forming composition of the second invention, each component of the surface free energy of the film obtained by curing the protective layer resin can take any range as long as the surface free energy is within the above range, but the dispersion component _γd is preferably 35 mN/ ^m2 or less, more preferably ³⁰ mN/m2 or less, preferably 10 mN/ ^m2 or more, more preferably 15 mN/ ^m2 or more, and even more preferably 18 mN/ ^m2 or more. In addition, the polar component _γh is preferably 5.0 mN/ ^m2 or less, more preferably 3.0 mN/ ^m2 or less. There is no particular limit to the lower limit of _γd , but it is usually 0.0 mN/ ^m2 or more.

As for the curable resin contained in the protective layer forming composition of the second invention, a method for making the surface free energy of the film obtained by curing the curable resin equal to or less than the above upper limit can be mentioned, for example, by using the protective layer forming composition of the present invention containing the photocurable silicone resin described below, particularly the photocurable silicone resin having fluorine atoms, as the photocurable resin to form the protective layer. That is, the photocurable silicone resin described below, particularly the photocurable silicone resin having fluorine atoms, can reduce the surface free energy by suppressing intermolecular interactions and reducing the dispersion component of the surface free energy.

The surface free energy of the protective layer formed using the protective layer-forming composition suitable for the present invention described below is usually about 10 to 32 mN/m ² , and preferably 15 to 30 mN/m ² .

In the second invention, the surface free energy is measured for the cured resin layer surface, the anisotropic dye film surface, and the protective layer surface, respectively, by the method described in the Examples section below.

[Characteristics of the optically anisotropic laminate of the third invention]
The optically anisotropic laminate of the third invention is characterized in that the protective layer is a layer formed from the protective layer-forming composition of the present invention, which contains a photocurable silicone resin described below.
When the protective layer-forming composition contains a photocurable silicone resin, good curability can be obtained, and the protective layer can exhibit sufficient protective performance.

[Anisotropic Dye Layer]
As described above, the anisotropic dye layer is a dye film having anisotropy in electromagnetic properties in any two directions selected from a total of three directions in a three-dimensional coordinate system, the thickness direction and any two orthogonal in-plane directions. Examples of the electromagnetic properties include optical properties such as absorption and refraction, and electrical properties such as resistance and capacitance.
Examples of the film having optical anisotropy such as absorption or refraction include a polarizing film such as a linear polarizing film or a circular polarizing film, a retardation film, and a conductive anisotropic dye film. The anisotropic dye film is preferably used as a polarizing film or a conductive anisotropic dye film, and more preferably as a polarizing film.
The anisotropic dye film can function as a polarizing film that obtains linearly polarized light, circularly polarized light, elliptically polarized light, etc. by utilizing the anisotropy of light absorption. In addition, depending on the selection of the film formation process and the composition containing the substrate and organic compound (dye or transparent material), the anisotropic dye film can function as various anisotropic dye films having refractive anisotropy, conductive anisotropy, etc.

When the optically anisotropic laminate of the present invention is used as a polarizing element for a liquid crystal display or an anti-reflection film for an OLED, the orientation characteristics of the anisotropic dye film can be expressed by a dichroic ratio. If the dichroic ratio is 8 or more, it functions as a polarizing element. The dichroic ratio is preferably 15 or more, more preferably 20 or more, even more preferably 25 or more, particularly preferably 30 or more, and most preferably 40 or more.
When the dichroic ratio is equal to or greater than the lower limit, the film is useful as an optical element, particularly a polarizing element, as described below.

When used as a polarizing element in an anti-reflection film for OLEDs, even if the performance of peripheral materials such as retardation films is low, if the performance of the polarizing element is high, the characteristics as an anti-reflection film will be improved. Therefore, if the performance of the polarizing element is high, it is easier to simplify the layer structure, and even a thin film structure can easily exhibit sufficient functionality, making it suitable for use in applications where it is used after being deformed, including folding and bending. It also makes it possible to keep costs low.

The dichroic ratio (D) in the present invention is expressed by the following formula when the dyes are uniformly oriented.
D = Az/Ay
Here, Az is the absorbance observed when the polarization direction of light incident on the anisotropic dye film is parallel to the orientation direction of the anisotropic dye, and Ay is the absorbance observed when the polarization direction of light incident on the anisotropic dye film is perpendicular to the orientation direction of the anisotropic dye.

There are no particular limitations on the absorbance of each, so long as they are of the same wavelength, any wavelength may be selected depending on the purpose. When expressing the degree of orientation of an anisotropic dye film, it is preferable to use a value corrected for visual sensitivity in a specific wavelength range of 380 nm to 780 nm for the anisotropic dye film, or a value at the maximum absorption wavelength in the visible range.

The transmittance of the anisotropic dye film of the present invention in the visible light wavelength range is preferably 25% or more, more preferably 35% or more, and particularly preferably 40% or more. The transmittance may be the upper limit according to the application. For example, when the degree of polarization is to be increased, the transmittance is preferably 50% or less. With a transmittance in the above range, the film is useful as an optical element, which will be described later, and is particularly useful as an optical element for liquid crystal displays used for color display, and as an anti-reflection film combining an anisotropic dye film and a retardation film.

The anisotropic dye film of the present invention has a dry thickness of preferably 10 nm or more, more preferably 100 nm or more, and even more preferably 500 nm or more. On the other hand, the anisotropic dye film of the present invention has a dry thickness of preferably 30 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less. By having the anisotropic dye film have a thickness in the above range, there is a tendency to obtain a uniform orientation of the dye within the film and a uniform film thickness.

[Anisotropic dye film-forming composition]
The anisotropic dye film of the present invention is formed using the composition for forming an anisotropic dye film of the present invention, which contains a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator.
The anisotropic dye film-forming composition of the present invention may contain additives and solvents other than the dye, the polymerizable liquid crystal compound and the photopolymerization initiator.

<Dye>
In the present invention, a dye is a substance or compound that absorbs at least a part of the wavelengths in the visible light region (380 nm to 780 nm).
Dyes that can be used in the present invention include dichroic dyes. A dichroic dye is a dye that has different absorbance in the long axis direction of the molecule and absorbance in the short axis direction. The dye may or may not have liquid crystallinity. Having liquid crystallinity means that a liquid crystal phase is expressed at any temperature.

The dyes contained in the anisotropic dye film-forming composition of the present invention, i.e., the dyes contained in the anisotropic dye film of the present invention, include azo dyes, quinone dyes (including naphthoquinone dyes, anthraquinone dyes, etc.), stilbene dyes, cyanine dyes, phthalocyanine dyes, indigo dyes, condensed polycyclic dyes (including perylene dyes, oxazine dyes, acridine dyes, etc.). Among these dyes, azo dyes are preferred because they have a large molecular long/short axis ratio and can achieve high molecular alignment in the anisotropic dye film.

Azo dyes are dyes that have at least one azo group (-N=N-), and the number of azo groups in one molecule is preferably 1 or more, more preferably 2 or more, and is preferably 6 or less, more preferably 4 or less, and even more preferably 3 or less, from the viewpoints of solubility in solvents, compatibility with liquid crystal compounds, color tone, and ease of production.

An example of the azo dye is a compound represented by the formula (A).
R ¹¹ -D ¹ -N=N-(D ² -N=N)p-D ³ -R ¹² ... (A)
In formula (A),
D ¹ , D ² and D ³ each independently represent a phenylene group which may have a substituent, a naphthylene group which may have a substituent, or a divalent heterocyclic group which may have a substituent;
p represents an integer of 0 to 4;
When p is an integer of 2 or more, multiple ^D2 may be the same or different;
R ¹¹ and R ¹² each independently represent a monovalent organic group.

D ¹ , D ² and D ³ each independently represent a phenylene group which may have a substituent, a naphthylene group which may have a substituent, or a divalent heterocyclic group which may have a substituent.
As the substitution position of the phenylene group, a 1,4-phenylene group is preferred because it provides high molecular linearity.
As the substitution position of the naphthylene group, a 1,4-naphthylene group or a 2,6-naphthylene group is preferred because the linearity of the molecule is high.

The divalent heterocyclic group is a heterocyclic group having a ring with preferably 3 to 14 carbon atoms, more preferably 10 or less. Monocyclic or bicyclic heterocyclic groups are particularly preferred.

The non-carbon atom constituting the divalent heterocyclic group is at least one selected from a nitrogen atom, a sulfur atom, and an oxygen atom. When a heterocyclic group has multiple non-carbon atoms constituting the ring, these may be the same or different.

Specific examples of divalent heterocyclic groups include pyridinediyl, quinolinediyl, isoquinolinediyl, thiazolediyl, benzothiazolediyl, thienothiazolediyl, thienothiophenediyl, benzimidazolidinonediyl, benzofurandiyl, phthalimidodiyl, oxazolediyl, and benzoxazolediyl groups.

Examples of the substituents that the phenylene group, naphthylene group, and divalent heterocyclic group in D ¹ , D ² , and D ³ may have include an alkyl group having 1 to 4 carbon atoms; an alkoxy group having 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, and a butoxy group; a fluorinated alkyl group having 1 to 4 carbon atoms, such as a trifluoromethyl group; a cyano group; a nitro group; a hydroxyl group; a halogen atom; and a substituted or unsubstituted amino group, such as an amino group, a diethylamino group, and a pyrrolidino group. Here, the substituted amino group means an amino group having one or two alkyl groups having 1 to 4 carbon atoms, or an amino group in which two substituted alkyl groups are bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms. The unsubstituted amino group is -NH _2. Examples of the alkyl group having 1 to 4 carbon atoms of the substituted amino group include a methyl group, an ethyl group, and a butyl group. Examples of the alkanediyl group having 2 to 8 carbon atoms include an ethylene group, a propane-1,3-diyl group, a butane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, and an octane-1,8-diyl group.

In terms of high molecular linearity, the phenylene group, naphthylene group, and divalent heterocyclic group in D ¹ , D ² , and D ³ are preferably unsubstituted, or, if substituted, are preferably substituted with a methyl group, a methoxy group, a hydroxyl group, a fluorine atom, a chlorine atom, a dimethylamino group, a pyrrolidinyl group, or a piperidinyl group.

p represents an integer of 0 to 4. From the viewpoints of solubility in solvents, compatibility with liquid crystal compounds, color tone, and ease of manufacture, p is preferably 1 or more, more preferably 4 or less, and even more preferably 3 or less.

R ¹¹ and R ¹² each independently represent a monovalent organic group.
Examples of the monovalent organic group in R ¹¹ and R ¹² include a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a branch; an alicyclic alkyl group having 1 to 20 carbon atoms; an alkoxy group having 1 to 20 carbon atoms which may have a branch, such as a methoxy group, an ethoxy group, and a butoxy group; a fluorinated alkyl group having 1 to 20 carbon atoms which may have a branch, such as a trifluoromethyl group; a cyano group; a nitro group; a hydroxyl group; a halogen atom; a substituted or unsubstituted amino group such as an amino group, a diethylamino group, and a pyrrolidino group; a carboxy group; an alkyloxycarbonyl group having 1 to 20 carbon atoms which may have a branch, such as a butoxycarbonyl group; Examples of the alkyl group include an alkenyl group having 1 to 20 carbon atoms; an alkylphenylalkenyl group such as a 2-(4-butylphenyl)ethenyl group; a carbamoyl group; an alkylcarbamoyl group having 1 to 20 carbon atoms, which may be branched, such as a butylcarbamoyl group; a sulfamoyl group; an alkylsulfamoyl group having 1 to 20 carbon atoms, which may be branched, such as a butylsulfamoyl group; an acylamino group having 1 to 20 carbon atoms, which may be branched, such as a butylcarbonylamino group; an acyloxy group having 1 to 20 carbon atoms, which may be branched, such as a butylcarbonyloxy group; a sulfanyl group; an alkylsulfanyl group having 1 to 20 carbon atoms, such as a butylsulfanyl group; and a chain organic group having polymerizable groups R ¹ and R ² in the liquid crystal compound described below. The substituted amino group refers to an amino group having one or two alkyl groups having 1 to 20 carbon atoms, which may be branched, or an amino group in which two substituted alkyl groups are bonded to each other to form an alkanediyl group having 2 to 20 carbon atoms. The unsubstituted amino group is -NH ₂ . Examples of the alkyl group having 1 to 20 carbon atoms in the substituted amino group include a methyl group, an ethyl group, and a butyl group. Examples of the alkanediyl group having 2 to 20 carbon atoms include an ethylene group, a propane-1,3-diyl group, a butane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, and an octane-1,8-diyl group.

Examples of R ¹¹ and R ¹² include a hydrogen atom, a chain group, an aliphatic organic group (the "aliphatic organic group" includes a chain and a cyclic group), and an aliphatic organic group in which a portion of the carbon is replaced with nitrogen and/or oxygen (the "aliphatic organic group in which a portion of the carbon is replaced with nitrogen and/or oxygen" includes a chain and a cyclic group, and includes a portion of the methyl group in the aliphatic organic group replaced with a hydroxyl group, an oxo group (=O), an amino group, an imino group, etc.). In one embodiment, R ¹¹ and R ¹² are preferably a hydrogen atom or a chain group. In another embodiment, R ¹¹ and R ¹² are preferably a hydrogen atom or an aliphatic organic group. In yet another embodiment, R ¹¹ and R ¹² are preferably a hydrogen atom or an aliphatic organic group in which a portion of the carbon atom is replaced with a nitrogen atom and/or an oxygen atom.

Examples of the chain group include the above-mentioned alkyl group having 1 to 20 carbon atoms, which may be branched; alkoxy group having 1 to 20 carbon atoms, which may be branched; fluorinated alkyl group having 1 to 20 carbon atoms, which may be branched; substituted or unsubstituted amino group (substituted amino group means an amino group having one or two alkyl groups having 1 to 20 carbon atoms, which may be branched. An unsubstituted amino group is _-NH2 ); carboxy group; alkyloxycarbonyl group having 1 to 20 carbon atoms, which may be branched; carbamoyl group; alkylcarbamoyl group having 1 to 20 carbon atoms, which may be branched; sulfamoyl group; alkylsulfamoyl group having 1 to 20 carbon atoms, which may be branched; acylamino group having 1 to 20 carbon atoms, which may be branched; acyloxy group having 1 to 20 carbon atoms, which may be branched; sulfanyl group; alkylsulfanyl group having 1 to 20 carbon atoms, and the like.

Aliphatic organic groups include the above-mentioned alkyl groups having 1 to 20 carbon atoms, which may be branched, and alicyclic alkyl groups having 1 to 20 carbon atoms.

Examples of the aliphatic organic group in which a part of the carbon atoms is replaced by a nitrogen atom and/or an oxygen atom include the above-mentioned alkoxy group having 1 to 20 carbon atoms, which may be branched; substituted or unsubstituted amino group; carboxy group; alkyloxycarbonyl group having 1 to 20 carbon atoms, which may be branched; carbamoyl group; alkylcarbamoyl group having 1 to 20 carbon atoms, which may be branched; acylamino group having 1 to 20 carbon atoms, which may be branched; and acyloxy group having 1 to 20 carbon atoms, which may be branched. The above-mentioned substituted amino group means an amino group having one or two alkyl groups having 1 to 20 carbon atoms, which may be branched, or an amino group in which two substituted alkyl groups are bonded to each other to form an alkanediyl group having 2 to 20 carbon atoms. The unsubstituted amino group is _-NH2 . Examples of the alkyl group having 1 to 20 carbon atoms of the substituted amino group include a methyl group, an ethyl group, and a butyl group. Examples of the alkanediyl group having 2 to 20 carbon atoms include an ethylene group, a propane-1,3-diyl group, a butane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, and an octane-1,8-diyl group.

From the viewpoint of high molecular linearity, R ¹¹ and R ¹² are each preferably independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms such as a butyl group, a pentyl group, a hexyl group, a heptyl group, or an octyl group, an alkoxy group having 1 to 10 carbon atoms such as a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, or an octyloxy group, a diethylamino group, a pyrrolidino group, or a piperidinyl group. In addition, the preferred chain organic groups having a polymerizable group of R ¹ and R ² in the liquid crystal compound described later are also preferably used.

The dye contained in the anisotropic dye film of the present invention is not particularly limited, and any known dye can be used.
Examples of known dyes include the dyes (dichroic dyes and dichroic dyes) described in the above-mentioned Patent Document 1, Japanese Patent No. 5982762, JP-A-2017-025317, and JP-A-2014-095899.

Specific examples include, but are not limited to, the dyes listed below.

The molecular weight of these dyes is preferably 300 or more, more preferably 350 or more, even more preferably 380 or more, and is preferably 1500 or less, more preferably 1200 or less, and even more preferably 1000 or less. Specifically, the molecular weight of the dye according to the present invention is preferably 300 to 1500, more preferably 350 to 1200, and even more preferably 380 to 1000. The molecular weight of the dye is the sum of the atomic weights contained in the dye molecule.

The content of the dye (dichroic dye) in the anisotropic dye film is, for example, preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, more preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 10 parts by mass or less, relative to the anisotropic dye film (100 parts by mass). Specifically, the content of the dye (dichroic dye) in the anisotropic dye film is, for example, preferably 0.01 to 50 parts by mass, more preferably 0.05 to 30 parts by mass, and even more preferably 0.05 to 10 parts by mass, relative to the anisotropic dye film (100 parts by mass). If the content of the dye (dichroic dye) is within the above range, the polymerizable liquid crystal compound tends to be polymerized while maintaining high orientation in the anisotropic dye film of the present invention. If the content of the dye (dichroic dye) is equal to or greater than the above lower limit, sufficient light absorption and sufficient polarization performance tend to be obtained. If the content of the dye (dichroic dye) is equal to or less than the upper limit, the alignment of the liquid crystal molecules tends to be less affected.

Therefore, the content of the dye (dichroic dye) in the anisotropic dye film-forming composition of the present invention is, for example, preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, more preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 10 parts by mass or less, relative to the solid content (100 parts by mass) in the anisotropic dye film-forming composition. Specifically, the content of the dye (dichroic dye) in the solid content in the anisotropic dye film-forming composition is, for example, preferably 0.01 to 50 parts by mass, more preferably 0.05 to 30 parts by mass, and even more preferably 0.05 to 10 parts by mass, relative to the solid content (100 parts by mass). If the content of the dye (dichroic dye) is within the above range, the polymerizable liquid crystal compound tends to be polymerized while maintaining high alignment in the anisotropic dye film-forming composition of the present invention. If the content of the dye (dichroic dye) is equal to or greater than the lower limit, sufficient light absorption and sufficient polarization performance tend to be obtained. If the content of the dye (dichroic dye) is equal to or less than the upper limit, the alignment of the liquid crystal molecules tends to be less affected.

Here, the solid content in the composition for forming an anisotropic dye film corresponds to the total of all components other than the solvent in the composition for forming an anisotropic dye film, and corresponds to the mass of the anisotropic dye film formed by the composition for forming an anisotropic dye film.

The anisotropic dye film-forming composition of the present invention and the anisotropic dye film of the present invention may contain only one type of dye, or may contain two or more types.

<Polymerizable Liquid Crystal Compound>
In the present invention, the liquid crystal compound refers to a substance that exhibits a liquid crystal state, and specifically refers to a compound that does not directly transition from a crystal to a liquid state but becomes a liquid state via an intermediate state that exhibits properties of both a crystal and a liquid, as described on pages 1 to 28 of "Liquid Crystal Handbook" (Maruzen Co., Ltd., published on October 30, 2000).

The polymerizable liquid crystal compound contained in the composition for forming an anisotropic dye film of the present invention is a liquid crystal compound having a polymerizable group, which will be described later.

In the polymerizable liquid crystal compound, the polymerizable group can be located at any position in the liquid crystal compound molecule. In the polymerizable liquid crystal compound, the polymerizable group is preferably substituted at the terminal of the liquid crystal compound molecule from the viewpoint of ease of polymerization.
In the polymerizable liquid crystal compound, one or more polymerizable groups may be present in the liquid crystal compound molecule. When two or more polymerizable groups are present, it is preferable that they are present at both ends of the liquid crystal compound molecule from the viewpoint of ease of polymerization.

The polymerizable liquid crystal compound is preferably a compound having a carbon-carbon triple bond in the liquid crystal compound molecule. In a compound having a carbon-carbon triple bond, the carbon-carbon triple bond is capable of rotational motion while also being able to become the core of the liquid crystal molecule, and the molecular mobility is high, and there is strong intermolecular interaction between the liquid crystal molecules and with compounds having a π-conjugated system such as dye molecules, which tends to result in high molecular orientation.

The polymerizable liquid crystal compound is preferably a low molecular weight liquid crystal compound that does not have a repeating structure containing units that exhibit liquid crystallinity, as this makes it easier to obtain a high dichroic ratio.

The polymerizable liquid crystal compound contained in the composition for forming an anisotropic dye film of the present invention is not particularly limited, and any liquid crystal compound having a polymerizable group can be used.

For example, the polymerizable liquid crystal compound contained in the anisotropic dye film-forming composition of the present invention may be a compound represented by the following formula (1) (hereinafter, sometimes referred to as "polymerizable liquid crystal compound (1)").

Q ¹ -R ¹ -A ¹¹ -Y ¹ -A ¹² -(Y ² -A ¹³ ) _k -R ² -Q ² ... (1)
(In formula (1),
^-Q1 represents a hydrogen atom or a polymerizable group;
^-Q2 represents a polymerizable group;
-R ¹ - and -R ² - each independently represent a chain organic group;
-A ¹¹ - and -A ¹³ - each independently represent a partial structure represented by the following formula (2), a divalent organic group, or a single bond;
-A ¹² - represents a partial structure represented by the following formula (2) or a divalent organic group;
Each of -Y ¹ - and -Y ² - independently represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C≡C-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -;
One of -A ¹¹ - and -A ¹³ - is a partial structure represented by the following formula (2) or a divalent organic group:
k is 1 or 2.
When k is 2, two -Y ² -A ¹³ - may be the same or different.

-Cy-X ² -C≡C-X ¹ - ... (2)
(In formula (2),
-Cy- represents a hydrocarbon ring group or a heterocyclic group;
-X ¹ - represents -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -;
-X ² - represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -.

When -A ¹¹ - is a partial structure represented by formula (2), formula (1) may be the following formula (1A) or the following formula (1B).
Q ¹ -R ¹ -Cy-X ² -C≡C-X ¹ -Y ¹ -A ¹² -(Y ² -A ¹³ ) _k -R ² -Q ² ... (1A)
Q ¹ -R ¹ -X ¹ -C≡C-X ² -Cy-Y ¹ -A ¹² -(Y ² -A ¹³ ) _k -R ² -Q ² ... (1B)

When -A ¹² - is a partial structure represented by formula (2), formula (1) may be the following formula (1C) or the following formula (1D).
Q ¹ -R ¹ -A ¹¹ -Y ¹ -Cy-X ² -C≡C-X ¹ -(Y ² -A ¹³ ) _k -R ² -Q ² ... (1C)
Q ¹ -R ¹ -A ¹¹ -Y ¹ -X ¹ -C≡C-X ² -Cy-(Y ² -A ¹³ ) _k -R ² -Q ² ... (1D)

When -A ¹³ - is a partial structure represented by formula (2), formula (1) may be the following formula (1E) or the following formula (1F).
Q ¹ -R ¹ -A ¹¹ -Y ¹ -A ¹² -(Y ² -Cy-X ² -C≡C-X ¹ ) _k -R ² -Q ² ... (1E)
Q ¹ -R ¹ -A ¹¹ -Y ¹ -A ¹² -(Y ² -X ¹ -C≡C-X ² -Cy) _k -R ² -Q ² ... (1F)

Similarly, when two or more of -A ¹¹ -, -A ¹² - and -A ¹³ - are partial structures represented by formula (2), the orientation of the partial structures represented by formula (2) may be inverted, independently of each other.

As described above, -A ¹¹ -, -A ¹² - and -A ¹³ - are each independently a partial structure or a divalent organic group represented by formula (2). In addition, -A ¹¹ - and -A ¹³ - may be a single bond, but -A ¹¹ - and -A ¹³ - are not both single bonds.

(-Cy-)
The hydrocarbon ring group in -Cy- includes aromatic hydrocarbon ring groups and non-aromatic hydrocarbon ring groups.
The aromatic hydrocarbon ring group includes an unlinked aromatic hydrocarbon ring group and a linked aromatic hydrocarbon ring group.

The non-linked aromatic hydrocarbon ring group is a divalent group of a monocyclic or condensed aromatic hydrocarbon ring, and preferably has 6 to 20 carbon atoms, because the appropriate core size provides good molecular orientation. The non-linked aromatic hydrocarbon ring group more preferably has 6 to 15 carbon atoms. Examples of aromatic hydrocarbon rings include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzpyrene ring, a chrysene ring, a triphenylene ring, an acenaphthene ring, a fluoranthene ring, and a fluorene ring.

The linked aromatic hydrocarbon ring group is a divalent group in which a plurality of monocyclic or condensed aromatic hydrocarbon rings are bonded by single bonds and have a bond on an atom constituting the ring. The number of carbon atoms in the monocyclic or condensed ring is preferably 6 to 20 because the molecular orientation is good due to the appropriate core size. The number of carbon atoms in the monocyclic or condensed ring is more preferably 6 to 15. Examples of the linked aromatic hydrocarbon ring group include a divalent group in which a first monocyclic or condensed aromatic hydrocarbon ring having 6 to 20 carbon atoms is bonded by a single bond to a second monocyclic or condensed aromatic hydrocarbon ring having 6 to 20 carbon atoms, which has a first bond on an atom constituting the ring of the first monocyclic or condensed aromatic hydrocarbon ring having 6 to 20 carbon atoms, and a second bond on an atom constituting the ring of the second monocyclic or condensed aromatic hydrocarbon ring having 6 to 20 carbon atoms. Specific examples of the linked aromatic hydrocarbon ring group include a biphenyl-4,4'-diyl group.

As the aromatic hydrocarbon ring group, a non-linked aromatic hydrocarbon ring group is preferable because it optimizes the intermolecular interaction acting between liquid crystal compounds, thereby improving the molecular alignment.
Of these, the aromatic hydrocarbon ring group is preferably a divalent group of a benzene ring or a divalent group of a naphthalene ring, and more preferably a divalent group of a benzene ring (phenylene group). As the phenylene group, a 1,4-phenylene group is preferable. When -Cy- is one of these groups, the linearity of the liquid crystal molecules is increased, and the effect of improving molecular alignment tends to be obtained.

Non-aromatic hydrocarbon ring groups include unlinked non-aromatic hydrocarbon ring groups and linked non-aromatic hydrocarbon ring groups.

The non-linked non-aromatic hydrocarbon ring group is a divalent group of a monocyclic or condensed non-aromatic hydrocarbon ring, and preferably has 3 to 20 carbon atoms because the appropriate core size provides good molecular orientation. The non-linked non-aromatic hydrocarbon ring group more preferably has 3 to 15 carbon atoms. Examples of non-aromatic hydrocarbon rings include a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, a cyclohexene ring, a norbornane ring, a bornane ring, an adamantane ring, a tetrahydronaphthalene ring, and a bicyclo[2.2.2]octane ring.

　The non-linked non-aromatic hydrocarbon ring group includes an alicyclic hydrocarbon ring group that does not have an unsaturated bond between the atoms that constitute the ring of the non-aromatic hydrocarbon ring, and an unsaturated non-aromatic hydrocarbon ring group that has an unsaturated bond between the atoms that constitute the ring of the non-aromatic hydrocarbon ring. From the viewpoint of productivity, the non-linked non-aromatic hydrocarbon ring group is preferably an alicyclic hydrocarbon ring group.

The linked non-aromatic hydrocarbon ring group is a divalent group in which a plurality of monocyclic or condensed non-aromatic hydrocarbon rings are bonded together with single bonds and has a bond on an atom constituting the ring; or a divalent group in which one or more rings selected from the group consisting of monocyclic aromatic hydrocarbon rings, condensed aromatic hydrocarbon rings, monocyclic non-aromatic hydrocarbon rings, and condensed non-aromatic hydrocarbon rings are bonded together with a monocyclic or condensed non-aromatic hydrocarbon ring with a single bond and has a bond on an atom constituting the ring.
The number of carbon atoms in the single ring or condensed ring is preferably 3 to 20 because an appropriate core size provides good molecular orientation.

Examples of the linked non-aromatic hydrocarbon ring group include a divalent group in which a first monocyclic or condensed non-aromatic hydrocarbon ring having 3 to 20 carbon atoms is bonded to a second monocyclic or condensed non-aromatic hydrocarbon ring having 3 to 20 carbon atoms by a single bond, the divalent group having a first bond on an atom constituting the first monocyclic or condensed non-aromatic hydrocarbon ring having 3 to 20 carbon atoms, and a second bond on an atom constituting the second monocyclic or condensed non-aromatic hydrocarbon ring having 3 to 20 carbon atoms. Further examples include a divalent group in which a monocyclic or condensed aromatic hydrocarbon ring having 3 to 20 carbon atoms is bonded to a monocyclic or condensed non-aromatic hydrocarbon ring having 3 to 20 carbon atoms by a single bond, the divalent group having a first bond on an atom constituting the monocyclic or condensed aromatic hydrocarbon ring having 3 to 20 carbon atoms, and a second bond on an atom constituting the monocyclic or condensed non-aromatic hydrocarbon ring having 3 to 20 carbon atoms.

Specific examples of linking non-aromatic hydrocarbon ring groups include bis(cyclohexane)-4,4'-diyl and 1-cyclohexylbenzene-4,4'-diyl groups.

As the non-aromatic hydrocarbon ring group, a non-linked non-aromatic hydrocarbon ring group is preferred because it optimizes the intermolecular interactions that act between liquid crystal compounds, thereby improving molecular orientation.

As the non-linked non-aromatic hydrocarbon ring group, a divalent group of cyclohexane (cyclohexanediyl group) is preferable. As the cyclohexanediyl group, a cyclohexane-1,4-diyl group is preferable. When -Cy- is one of these groups, the linearity of the liquid crystal molecules is increased, and the effect of improving molecular alignment tends to be obtained.

The heterocyclic group in -Cy- includes aromatic heterocyclic groups and non-aromatic heterocyclic groups.

Aromatic heterocyclic groups include unlinked aromatic heterocyclic groups and linked aromatic heterocyclic groups.

The non-linked aromatic heterocyclic group is a divalent group of a monocyclic or condensed aromatic heterocyclic ring, and preferably has 4 to 20 carbon atoms because the appropriate core size provides good molecular orientation. The non-linked aromatic heterocyclic group more preferably has 4 to 15 carbon atoms.

Aromatic heterocycles include furan ring, benzofuran ring, thiophene ring, benzothiophene ring, pyrrole ring, pyrazole ring, imidazole ring, thiazole ring, isothiazole ring, oxadiazole ring, thiadiazole ring, triazole ring, indole ring, carbazole ring, pyrroloimidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, thienothiophene ring, furopyrrole ring, furofuran ring, thienofuran ring, thienothiazole ring, benzoisoxazole ring, benzoisothiazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine ring, pyrimidine ring, triazine ring, quinoline ring, isoquinoline ring, cinnoline ring, quinoxaline ring, phenanthridine ring, quinazoline ring, quinazolinone ring, azulene ring, etc.

The linked aromatic heterocyclic group is a divalent group in which multiple monocyclic or condensed aromatic heterocyclic rings are bonded with single bonds and have bonds on the atoms that make up the ring. The number of carbon atoms in the monocyclic or condensed ring is preferably 4 to 20, because the appropriate core size provides good molecular orientation. The number of carbon atoms in the linked aromatic heterocyclic group is more preferably 4 to 15.

Examples of linked aromatic heterocyclic groups include divalent groups in which a first monocyclic or condensed aromatic heterocyclic ring having 4 to 20 carbon atoms is bonded to a second monocyclic or condensed aromatic heterocyclic ring having 4 to 20 carbon atoms by a single bond, the divalent group having a first bond on an atom constituting the ring of the first monocyclic or condensed aromatic heterocyclic ring having 4 to 20 carbon atoms, and a second bond on an atom constituting the ring of the second monocyclic or condensed aromatic heterocyclic ring having 4 to 20 carbon atoms.

Non-aromatic heterocyclic groups include unlinked non-aromatic heterocyclic groups and linked non-aromatic heterocyclic groups.

The non-linked non-aromatic heterocyclic group is a divalent group of a monocyclic or condensed non-aromatic heterocyclic ring, and preferably has 4 to 20 carbon atoms because the appropriate core size provides good molecular orientation. The non-linked non-aromatic heterocyclic group more preferably has 4 to 15 carbon atoms.

Examples of non-aromatic heterocycles that are divalent groups of monocyclic or condensed non-aromatic heterocycles having 4 to 20 carbon atoms include a tetrahydrofuran ring, a tetrahydropyran ring, a dioxane ring, a tetrahydrothiophene ring, a tetrahydrothiopyran ring, a pyrrolidine ring, a piperidine ring, a dihydropyridine ring, a piperazine ring, a tetrahydrothiazole ring, a tetrahydrooxazole ring, an octahydroquinoline ring, a tetrahydroquinoline ring, an octahydroquinazoline ring, a tetrahydroquinazoline ring, a tetrahydroimidazole ring, a tetrahydrobenzimidazole ring, and a quinuclidine ring.

　A linked non-aromatic heterocyclic group is a divalent group in which multiple monocyclic or condensed non-aromatic heterocyclic rings are bonded with single bonds and have bonds on the atoms that make up the ring. The number of carbon atoms in the monocyclic or condensed ring is preferably 4 to 20, because the appropriate core size provides good molecular orientation. The number of carbon atoms in the linked non-aromatic heterocyclic group is more preferably 4 to 15.

Examples of linked aromatic heterocyclic groups include divalent groups in which a first monocyclic or condensed non-aromatic heterocyclic ring having 4 to 20 carbon atoms is bonded to a second monocyclic or condensed non-aromatic heterocyclic ring having 4 to 20 carbon atoms by a single bond, the divalent group having a first bond on an atom constituting the ring of the first monocyclic or condensed non-aromatic heterocyclic ring having 4 to 20 carbon atoms, and a second bond on an atom constituting the ring of the second monocyclic or condensed non-aromatic heterocyclic ring having 4 to 20 carbon atoms.

The aromatic hydrocarbon ring group, non-aromatic hydrocarbon ring group, aromatic heterocyclic group and non-aromatic heterocyclic group in -Cy- may each be substituted with one or more groups selected from the group consisting of -R ^k , -OH, -O-R ^k , -O-C(=O)-R ^k , -NH ₂ , -NH-R ^k , -N(R ^k ')-R ^k , -C(=O)-R ^k , -C(=O)-O-R ^k , -C(=O)-NH ₂ , -C(=O)-NH-R ^k , -C(=O)-N(R ^k ')-R ^k , -SH, -S-R ^k , trifluoromethyl group, sulfamoyl group, carboxy group, sulfo group, cyano group, nitro group and halogen. Here, -R ^k and -R ^k ' each independently represent a linear or branched alkyl group having 1 to 6 carbon atoms.

The aromatic hydrocarbon ring group, non-aromatic hydrocarbon ring group, aromatic heterocyclic group, and non-aromatic heterocyclic group in -Cy- are each preferably independently unsubstituted or substituted with a methyl group, a methoxy group, a fluorine atom, a chlorine atom, or a bromine atom, and more preferably unsubstituted, in that the molecular structure has a high linearity and the polymerizable liquid crystal compounds (1) are likely to associate with each other and exhibit a liquid crystal state.

The substituents of the aromatic hydrocarbon ring group, non-aromatic hydrocarbon ring group, aromatic heterocyclic group, and non-aromatic heterocyclic group in -Cy- may be the same or different. In addition, the aromatic hydrocarbon ring group, non-aromatic hydrocarbon ring group, aromatic heterocyclic group, and non-aromatic heterocyclic group may be entirely substituted, entirely unsubstituted, or partially substituted and partially unsubstituted.

As -Cy-, a hydrocarbon ring group is preferable because it improves the molecular alignment of the polymerizable liquid crystal compound (1), and a phenylene group or a cyclohexanediyl group is more preferable. As -Cy-, a 1,4-phenylene group or a cyclohexane-1,4-diyl group is even more preferable because it can increase the linearity of the molecular structure of the polymerizable liquid crystal compound (1), and a 1,4-phenylene group is particularly preferable.

-X ¹ - represents -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S- or -SCH ₂ -. Among these, -X ¹ - is preferably -C(═O)O-, -OC(═O)-, -C(═S)O-, -OC(═S)-, -C(═O)S-, -SC(═O)-, -CH 2 CH 2 -, -CH 2 O-, -OCH 2 -, -CH ₂ S-, -SCH ₂ -, etc., which have small π bonding property, because the polymerizable liquid crystal compound (1) tends to have linearity and easy rotational motion around the molecular short axis. Among these, -C(═O)O-, -OC ₍ ═O)-, -CH ₂ CH ₂ -, -CH ₂ O-, -OCH ₂ -, are more preferable _, and -X ₁ ^- is _still more preferably -C(═O)O- or -OC(═O)-. In another embodiment, —X ¹ — is preferably —CH ₂ CH ₂ —, —CH ₂ O— or —OCH ₂ —.

-X ² - represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S-, or -SCH ₂ -.

From the viewpoint of enlarging the core of the polymerizable liquid crystal compound (1) and increasing the dichroism of the anisotropic dye film, it is preferable to link -Cy- and -C≡C- with a group having high linearity. Specifically, -X ² - is preferably a single bond, or -C(═O)O-, -OC(═O)-, -C(═S)O-, -OC(═S)-, -C(═O)S-, -SC(═O)-, -CH═CH-, -C(═O)NH- or -NHC(═O)- having π-bonding property, and is more preferably a single bond due to its higher linearity.

The polymerizable group in ^-Q1 and ^-Q2 is a group having a partial structure capable of being polymerized by light, heat, and/or radiation, and is a functional group or atomic group necessary for ensuring the function of polymerization. From the viewpoint of producing an anisotropic dye film, the polymerizable group is preferably a photopolymerizable group.

Examples of polymerizable groups include acryloyl groups, methacryloyl groups, acryloyloxy groups, methacryloyloxy groups, acryloylamino groups, methacryloylamino groups, vinyl groups, vinyloxy groups, ethynyl groups, ethynyloxy groups, 1,3-butadienyl groups, 1,3-butadienyloxy groups, oxiranyl groups, oxetanyl groups, glycidyl groups, glycidyloxy groups, styryl groups, and styryloxy groups. Among these, acryloyl group, methacryloyl group, acryloyloxy group, methacryloyloxy group, acryloylamino group, methacryloylamino group, oxiranyl group, glycidyl group, and glycidyloxy group are preferred, acryloyl group, methacryloyl group, acryloyloxy group, methacryloylamino group, methacryloylamino group, glycidyl group, and glycidyloxy group are more preferred, and acryloyloxy group, methacryloyloxy group, and glycidyloxy group are even more preferred.

The chain organic group in -R ¹ - and -R ² - is a divalent organic group that does not contain a cyclic structure such as the above-mentioned aromatic hydrocarbon ring, non-aromatic hydrocarbon ring, aromatic heterocycle, or non-aromatic heterocycle.
Examples of such a chain organic group include -(alkylene group)-, -O-(alkylene group)-, -S-(alkylene group)-, -NH-(alkylene group)-, -N(alkyl)-(alkylene group)-, -OC(=O)-(alkylene group)-, and -C(=O)O-(alkylene group)-.

Examples of the alkylene group in these chain organic groups include linear or branched alkylene groups having 1 to 25 carbon atoms. The carbon-carbon bonds of the alkylene group may be partially unsaturated. One or more methylene groups contained in the alkylene group may be displaced by -O-, -S-, -NH-, -N(R ^m )-, -C(═O)-, -C(═O)-O-, -C(═O)-NH-, -CHF-, -CF ₂ -, -CHCl-, or -CCl ₂ -. Here, R ^m represents a linear or branched alkyl group having 1 to 6 carbon atoms.

The alkylene group in these chain organic groups is preferably a straight-chain alkylene group having 1 to 25 carbon atoms, in which some of the carbon atoms in the alkylene group may be unsaturated, and in which one or more methylene groups contained in the alkylene group may be replaced (displaced) by the above-mentioned groups, due to their high molecular linearity.

The number of atoms in the main chain (meaning the longest chain portion in the chain organic group) in the chain organic group is preferably 3 to 25, more preferably 5 to 20, and even more preferably 6 to 20.

As the chain organic group, -(CH ₂ ) _r -CH ₂ -, -O-(CH ₂ ) _r -CH ₂ -, -(O) _r1 -(CH ₂ CH ₂ O) _r2 -(CH ₂ ) _r3 -, -(O) _r1 -(CH ₂ ) _r2 -(CH ₂ CH ₂ O) _r3 - are preferred. In addition, r in these formulas is an integer of 1 to 24, preferably an integer of 2 to 24, more preferably an integer of 4 to 19, and even more preferably an integer of 5 to 19. In addition, r1, r2, and r3 in these formulas each independently represent an integer, and the number of atoms in the main chain (meaning the longest chain portion in the chain organic group) in the chain organic group is appropriately adjusted to be preferably 3 to 25, more preferably 5 to 20, and even more preferably 6 to 20.

It is preferable that -R ¹ - and -R ² - are each independently -(alkylene group)- or -O-(alkylene group)-. In one embodiment, the chain organic group in -R ¹ - and -R ² - is -(alkylene group)-, and in another embodiment, is -O-(alkylene group)-.

When -X ¹ - and -R ¹ - or -X ¹ - and -R ² - are bonded to each other as in the formula (1B) or (1E), or when -A ¹³ - in the formula (1B) is a single bond or when -A ¹¹ - in the formula (1E) is a single bond and -R ¹ - or -R ² - is bonded to -Y ¹ - or -Y ² -, it is preferable that -R ¹ - or -R ² - which is directly bonded to -X ¹ -, -Y ¹ - or -Y ² - is -(alkylene group)-.

In addition to the above, -R ¹ - or -R ² - which is not directly bonded to -X ¹ -, -Y ¹ - or -Y ² - is preferably -O-(alkylene group)-.

The divalent organic group in -A ¹¹ -, -A ¹² - and -A ¹³ - is preferably a group represented by the following formula (3).

-Q ³ - ... (3)
(In formula (3), ^Q3 represents a hydrocarbon ring group or a heterocyclic group.)

The hydrocarbon ring group in -Q ³ - includes an aromatic hydrocarbon ring group and a non-aromatic hydrocarbon ring group.

Aromatic hydrocarbon ring groups include unlinked aromatic hydrocarbon ring groups and linked aromatic hydrocarbon ring groups.

The non-linked aromatic hydrocarbon ring group is a divalent group of a monocyclic or condensed aromatic hydrocarbon ring, and preferably has 6 to 20 carbon atoms because the appropriate core size provides good molecular orientation. The non-linked aromatic hydrocarbon ring group more preferably has 6 to 15 carbon atoms. Examples of aromatic hydrocarbon rings include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzpyrene ring, a chrysene ring, a triphenylene ring, an acenaphthene ring, a fluoranthene ring, and a fluorene ring.

　The linked aromatic hydrocarbon ring group is a divalent group in which a plurality of monocyclic or condensed aromatic hydrocarbon rings are bonded by single bonds and have a bond on an atom constituting the ring. The number of carbon atoms in the monocyclic or condensed ring is preferably 6 to 20 because the appropriate core size provides good orientation. The number of carbon atoms in the linked aromatic hydrocarbon ring group is more preferably 6 to 15. Examples of the linked aromatic hydrocarbon ring group include a divalent group in which a first monocyclic or condensed aromatic hydrocarbon ring having 6 to 20 carbon atoms is bonded by a single bond to a second monocyclic or condensed aromatic hydrocarbon ring having 6 to 20 carbon atoms, which has a first bond on an atom constituting the ring of the first monocyclic or condensed aromatic hydrocarbon ring having 6 to 20 carbon atoms, and a second bond on an atom constituting the ring of the second monocyclic or condensed aromatic hydrocarbon ring having 6 to 20 carbon atoms. Specific examples of the linked aromatic hydrocarbon ring group include biphenyl-4,4'-diyl groups.

As the aromatic hydrocarbon ring group, a non-linked aromatic hydrocarbon ring group is preferable because it optimizes the intermolecular interaction acting between liquid crystal compounds, thereby improving the molecular alignment.
Of these, the aromatic hydrocarbon ring group is preferably a divalent group of a benzene ring or a divalent group of a naphthalene ring, and more preferably a divalent group of a benzene ring (phenylene group). As the phenylene group, a 1,4-phenylene group is preferable. When -Q ³ - is one of these groups, the linearity of the liquid crystal molecules is increased, and the effect of improving molecular alignment tends to be obtained.

As an unlinked non-aromatic hydrocarbon ring group, a divalent group of cyclohexane (cyclohexanediyl group) is preferred. As a cyclohexanediyl group, a cyclohexane-1,4-diyl group is preferred.

The heterocyclic group in -Q ³ - includes an aromatic heterocyclic group and a non-aromatic heterocyclic group.

The aromatic heterocyclic group includes an unlinked aromatic heterocyclic group and a linked aromatic heterocyclic group.

Aromatic heterocycles include a furan ring, a benzofuran ring, a thiophene ring, a benzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, a thiazole ring, an oxadiazole ring, an indole ring, a carbazole ring, a pyrroloimidazole ring, a pyrrolopyrazole ring, a pyrrolopyrrole ring, a thienopyrrole ring, a thienothiophene ring, a furopyrrole ring, a furofuran ring, a thienofuran ring, a thienothiazole ring, a benzisoxazole ring, a benzisothiazole ring, a benzimidazole ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinoxaline ring, a phenanthridine ring, a quinazoline ring, a quinazolinone ring, and an azulene ring.

The aromatic hydrocarbon ring group, non-aromatic hydrocarbon ring group, aromatic heterocyclic group and non-aromatic heterocyclic group in -Q ³ - may each be substituted with one or more groups selected from the group consisting of -R ⁿ , -OH, -O-R ⁿ , -O-C(═O)-R ⁿ , -NH ₂ , -NH-R ⁿ , -N(R ^n' )-R ⁿ , -C(═O)-R ⁿ , -C( ^═O )-O-R ⁿ , -C(═O)-NH ₂ , -C(═O)-NH-R n, -C(═O)-N(R ^n' )-R ⁿ , -SH, -S-R ⁿ , trifluoromethyl group, sulfamoyl group, carboxy group, sulfo group, cyano group, nitro group and halogen. Here, ^-Rn and -Rn ^' each independently represent a linear or branched alkyl group having 1 to 6 carbon atoms.

The aromatic hydrocarbon ring group, non-aromatic hydrocarbon ring group, aromatic heterocyclic group and non-aromatic heterocyclic group in -Q ³ - are each preferably independently unsubstituted or substituted with a methyl group, a methoxy group, a fluorine atom, a chlorine atom or a bromine atom, and more preferably unsubstituted, in terms of high linearity of the molecular structure, and ease of association of the polymerizable liquid crystal compounds (1) with each other to exhibit a liquid crystal state.

The substituents possessed by the aromatic hydrocarbon ring group, non-aromatic hydrocarbon ring group, aromatic heterocyclic group and non-aromatic heterocyclic group in -Q ³ - may be the same or different, and the aromatic hydrocarbon ring group, non-aromatic hydrocarbon ring group, aromatic heterocyclic group and non-aromatic heterocyclic group may be entirely substituted, entirely unsubstituted, or partially substituted and partially unsubstituted.

The substituents possessed by the divalent organic groups in -A ¹¹ -, -A ¹² - and -A ¹³ - may be the same or different, and all of the divalent organic groups in -A ¹¹ -, -A ¹² - and -A ¹³ - may be substituted, all of them may be unsubstituted, or some of them may be substituted and some of them may be unsubstituted.

-Q ³ - is preferably a hydrocarbon ring group, more preferably a phenylene group or a cyclohexanediyl group, and further preferably ^a 1,4-phenylene group or a cyclohexane-1,4-diyl group, since the linearity of the molecular structure of the polymerizable liquid crystal compound (1) can be increased.

As the divalent organic group of -A ¹¹ -, -A ¹² - and -A ¹³ -, -Q ³ - is preferably a hydrocarbon ring group, i.e., the divalent organic group is preferably a hydrocarbon ring group. As the divalent organic group, a phenylene group or a cyclohexanediyl group is more preferable, and a 1,4-phenylene group or a cyclohexane-1,4-diyl group is even more preferable because the linearity of the molecular structure of the polymerizable liquid crystal compound (1) can be increased.

In the polymerizable liquid crystal compound (1), it is preferable that one of -A ¹¹ -, -A ¹² -, and -A ¹³ - is a partial structure represented by formula (2), and the other two are each independently a divalent organic group. Of -A ¹¹ -, -A ¹² -, and -A ¹³ -, it is preferable that -Cy- in the partial structure represented by formula (2) is a hydrocarbon ring group, and it is particularly preferable that the divalent organic group is a hydrocarbon ring group. Furthermore, it is preferable that the hydrocarbon ring group is a 1,4-phenylene group or a cyclohexane-1,4-diyl group. It is also preferable that one of -A ¹¹ - and -A ¹³ - is a cyclohexane-1,4-diyl group.

It is more preferable that one of -A ¹¹ - and -A ¹³ - is a partial structure represented by formula (2), and the remaining one and -A ¹² - are divalent organic groups. In this case, it is preferable that one of -A ¹¹ - and -A ¹³ - which is a divalent organic group is a cyclohexane-1,4-diyl group, and it is particularly preferable that -A ¹² - is a 1,4-phenylene group.

Each of -Y ¹ - and -Y ² - independently represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C≡C-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S- or -SCH ₂ -. Since the polymerizable liquid crystal compound (1) tends to have linearity and easy rotational motion around the molecular short axis, -Y ¹ - and -Y ² - are each independently preferably a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH ₂ CH ₂ -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH ₂ O-, -OCH ₂ -, -CH ₂ S- or -SCH ₂ -, which have small π-bonding property, and more preferably a single bond, -C(=O)O-, -OC(=O)-, -CH ₂ CH ₂ -, -CH ₂ O- or -OCH ₂ -.

When -X ¹ - and -Y ¹ - or -X 1 - and -Y ² - are bonded as in the formulae (1A), (1C), (1D) and (1F), -Y ¹ - bonded to -X ¹ - or -Y ² - bonded to -X ¹ - is preferably a single bond. The other of -X ¹ -, -Y ¹ - and -Y ² ^- is preferably -C(═O)O- or -OC(═O)-.

When -X ¹ - is not bonded to either -Y ¹ - or -Y ² - as in the above formula (1B) and formula (1E), -X ¹ - is preferably -CH ₂ CH ₂ -, -CH ₂ O- or -OCH ₂ -, and both -Y ¹ - and -Y ² - are preferably -C(=O)O- or -OC(=O)-.

k is 1 or 2. In one embodiment, k is preferably 1. In another embodiment, k is preferably 2.
When k is 2, each -Y ² - may be the same or different, and each -A ¹³ - may be the same or different.

As the polymerizable liquid crystal compound (1), it is preferable that the compound be represented by the above formula (1A), (1B), (1E) or (1F) because it optimizes the intermolecular interactions acting between the liquid crystal compounds and has an appropriate core size, resulting in good molecular orientation.

As described above, the polymerizable liquid crystal compound (1) is preferably a low molecular weight compound that does not have a repeating structure containing a unit that exhibits liquid crystallinity, and therefore preferably has the compound structure represented by the formula (1). Here, "does not have a repeating structure containing a unit that exhibits liquid crystallinity" refers to a structure that does not have two or more repeating units that exhibit liquid crystallinity, as represented by a polymer liquid crystal compound.

The molecular weight of the polymerizable liquid crystal compound (1) is preferably 2000 or less, more preferably 1500 or less, and even more preferably 1000 or less. There is no particular lower limit, but it is preferably 400 or more, and more preferably 500 or more. The molecular weight of the polymerizable liquid crystal compound (1) is, for example, preferably 400 to 2000, more preferably 400 to 1500, and particularly preferably 500 to 1000. The molecular weight of the polymerizable liquid crystal compound is the sum of the atomic weights contained in the polymerizable liquid crystal compound molecule.

(Specific Examples of Polymerizable Liquid Crystal Compounds)
Specific examples of the polymerizable liquid crystal compound contained in the anisotropic dye film of the present invention include, but are not limited to, the polymerizable liquid crystal compounds described below. In the following exemplary formulae, C ₆ H ₁₃ represents an n-hexyl group. C ₅ H ₁₁ represents an n-pentyl group.

The liquid crystal compound contained in the composition for forming an anisotropic dye film of the present invention is preferably a polymerizable liquid crystal compound (1). The composition for forming an anisotropic dye film of the present invention may contain only one type of polymerizable liquid crystal compound alone, or may contain two or more types in any combination and ratio.

The content of the liquid crystal compound in the anisotropic dye film-forming composition of the present invention (when two or more liquid crystal compounds are used in combination, the sum of the respective contents) is preferably 50 parts by mass or more, more preferably 55 parts by mass or more, and preferably 99 parts by mass or less, and more preferably 98 parts by mass or less, relative to the solid content (100 parts by mass) of the anisotropic dye film-forming composition. If the content of the liquid crystal compound is within the above range, the alignment of the liquid crystal molecules tends to be high.

The anisotropic dye film-forming composition of the present invention may contain one or more polymerizable or non-polymerizable liquid crystal compounds other than the polymerizable liquid crystal compound (1). However, from the viewpoint of more effectively obtaining the effects of the present invention by using the polymerizable liquid crystal compound (1), the proportion of the polymerizable liquid crystal compound (1) in the total amount of liquid crystal compounds contained in the anisotropic dye film-forming composition of the present invention (100% by mass) is preferably 5% by mass or more, more preferably 10% by mass or more, and particularly preferably 15 to 100% by mass.

From the viewpoint of processing, the polymerizable liquid crystal compound contained in the composition for forming an anisotropic dye film of the present invention preferably has an isotropic phase appearance temperature of 160° C. or less, more preferably 140° C. or less, even more preferably 115° C. or less, even more preferably 110° C. or less, and particularly preferably 105° C. or less.
Here, the isotropic phase appearance temperature means the phase transition temperature from liquid crystal to liquid and the phase transition temperature from liquid to liquid crystal. In the present invention, it is preferable that at least one of these phase transition temperatures is equal to or lower than the above upper limit, and it is more preferable that both of these phase transition temperatures are equal to or lower than the above upper limit.

(Relationship between polymerizable liquid crystal compound and dye)
The ratio (r _n1 /r _n2 ) of the number of ring structures (r _n1 ) of the polymerizable liquid crystal compound contained in the anisotropic dye film-forming composition of the present invention to the number of ring structures (r _n2 ) of the dye is not particularly limited, but is preferably 0.7 to 1.5. This is because, from the viewpoint of facilitating improvement of the alignment of the anisotropic dye film, it is preferable that the difference between the molecular length of the polymerizable liquid crystal compound and the molecular length of the dye is smaller, since this leads to stronger intermolecular interaction between the liquid crystal molecules and the dye molecules and makes it difficult for the dye molecules to inhibit association between the liquid crystal molecules.
In addition, a fused ring in which two or more rings are fused is counted as one ring structure.

Here, the number of ring structures ( _rn2 ) will be explained using the compound represented by the above formula (A) as an example. The number of ring structures is the sum of ^D1 , ^D2 , and ^D3 in formula (A), and specifically, when p is 0, _rn2 is 2; when p is 1, _rn2 is 3; and when p is 4, _rn2 is 6.
Even if -R ¹¹ and -R ¹² are cyclic functional groups such as a pyrrolidinyl group or a piperidinyl group, the ring structures contained in -R ¹¹ and -R ¹² are not included in the number (r _n2 ) of ring structures possessed by the compound represented by formula (A).
The number of ring structures (r _n1 ) contained in the polymerizable liquid crystal compound does not include ring structures (such as oxirane rings and oxetane rings) contained in the polymerizable group in the polymerizable liquid crystal compound.

(Method for producing polymerizable liquid crystal compound)
The polymerizable liquid crystal compound contained in the composition for forming an anisotropic dye film of the present invention can be produced by combining known chemical reactions such as an alkylation reaction, an esterification reaction, an amidation reaction, an etherification reaction, an ipso substitution reaction, and a coupling reaction using a metal catalyst.
For example, the polymerizable liquid crystal compound contained in the composition for forming an anisotropic dye film of the present invention can be synthesized according to the method described in the Examples below or the method described on pages 449 to 468 of "Liquid Crystal Handbook" (Maruzen Co., Ltd., published on October 30, 2000).

<Photopolymerization initiator>
The photopolymerization initiator in the present invention is a polymerization initiator that generates active radicals by the action of light, and is a compound that can initiate the polymerization reaction of a polymerizable liquid crystal compound.

The maximum absorption wavelength of the photopolymerization initiator is preferably 260 nm or more, more preferably 280 nm or more, and even more preferably 300 nm or more. The maximum absorption wavelength of the photopolymerization initiator is preferably 440 nm or less, more preferably 420 nm or less, even more preferably 400 nm or less, and even more preferably 380 nm or less. Having a maximum absorption wavelength in this range allows the photopolymerization reaction to proceed sufficiently, and has the effect of obtaining an anisotropic dye film with a good degree of hardening.

Usable photopolymerization initiators include, for example, titanocene derivatives; biimidazole derivatives; halomethylated oxadiazole derivatives; halomethyl-s-triazine derivatives; alkylphenone derivatives; oxime ester derivatives; benzoins; benzophenone derivatives; acylphosphine oxide derivatives; iodonium salts; sulfonium salts; anthraquinone derivatives; thioxanthone derivatives; acridine derivatives; phenazine derivatives; anthrone derivatives; phenylglyoxylate derivatives; ketosulfone derivatives, organic peroxides, etc.

Among these photopolymerization initiators, alkylphenone derivatives, oxime ester derivatives, biimidazole derivatives, and thioxanthone derivatives are more preferred because they allow the photopolymerization reaction to proceed sufficiently and produce a film with a high degree of hardening.

Specific examples of titanocene derivatives include dichlorobis(cyclopentadienyl)titanium, bis(cyclopentadienyl)diphenyltitanium, bis(cyclopentadienyl)bis(2,3,4,5,6-pentafluorophenyl)titanium, bis(methylcyclopentadienyl)bis(2,3,5,6-tetrafluorophenyl)titanium, bis(cyclopentadienyl)bis(2,4,6-trifluorophenyl)titanium, bis(cyclopentadienyl)bis(2,6-difluorophenyl)titanium, bis(cyclopentadienyl)bis(2,4-difluorophenyl)titanium, bis(methylcyclopentadienyl)bis(2,3,4,5,6-pentafluorophenyl)titanium, bis(methylcyclopentadienyl)bis(2,6-difluorophenyl)titanium, and bis(cyclopentadienyl)bis[2,6-difluoro-3-(pyrrol-1-yl)phenyl]titanium.

Biimidazole derivatives include 2-(2'-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(2'-chlorophenyl)-4,5-bis(3'-methoxyphenyl)imidazole dimer, 2-(2'-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(2'-methoxyphenyl)-4,5-diphenylimidazole dimer, 2-(4'-methoxyphenyl)-4,5-diphenylimidazole dimer, etc.

Halomethylated oxadiazole derivatives include 2-(2-benzofuranyl)-5-trichloromethyl-1,3,4-oxadiazole, 2-[2-(2-benzofuranyl)ethenyl]-5-trichloromethyl-1,3,4-oxadiazole, 2-trichloromethyl-5-furyl-1,3,4-oxadiazole, 2-phenyl-5-trichloromethyl-1,3,4-oxadiazole, 2-(1-naphthyl)-5-trichloromethyl-1,3,4-oxadiazole, 2-(2-naphthyl)-5-trichloromethyl-1,3,4-oxadiazole, 2-styryl-5-trichloromethyl-1,3,4-oxadiazole, and 2-(4-methoxystyryl)-5-trichloromethyl-1,3,4-oxadiazole.

Halomethyl-s-triazine derivatives include 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-ethoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-ethoxycarbonylnaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(4-methoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-(3,4-dimethoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-[2-(2-furanyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine.

Alkylphenone derivatives include 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholinophenyl)butan-1-one, 3,6-bis(2-methyl-2-morpholinopropionyl)-9-octylcarbazole, benzyl dimethyl ketal, Examples include 2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-(4-isopropylphenyl)propanone, and 2-hydroxy-2-methyl-1-(4-dodecylphenyl)propanone.

Oxime ester derivatives include 2-(benzoyloxyimino)-1-[4-(phenylthio)phenyl]-1-octanone, O-acetyl-1-[6-(2-methylbenzoyl)-9-ethyl-9H-carbazol-3-yl]ethanone oxime, (9-ethyl-6-nitrocarbazol-3-yl)-[2-methyl-4-(3-methoxypropyl-2-yloxy)phenyl]-methylideneaminoacetate, JP 2000-80068 A, JP 2006-36750 A, JP 2008-17 Examples of such oxime ester derivatives include those described in Japanese Patent Publication No. 9611, Japanese Patent Application Laid-Open No. 2011-132215, Japanese Patent Publication No. 2012-526185, International Publication No. 2008/078678, International Publication No. 2009/131189, International Publication No. 2012/045736, International Publication No. 2012/068879, International Publication No. 2013/165207, International Publication No. 2014/121701, International Publication No. 2016/036910, International Publication No. 2017/030005, and International Publication No. 2018/097580.

Examples of benzoins include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, benzoin isobutyl ether, and benzoin isopropyl ether.

Examples of benzophenone derivatives include benzophenone, Michler's ketone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(methylethylamino)benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 2-chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone, o-methylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, and 2,4,6-trimethylbenzophenone.

Acylphosphine oxide derivatives include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and ethyl (2,4,6-trimethylbenzoyl)phenylphosphineate.

Iodonium salts include diphenyliodonium tetrakis(pentafluorophenyl)borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, di(4-nonylphenyl)iodonium hexafluorophosphate, 4-(methylphenyl)[4-(2-methylpropyl)phenyl]iodonium hexafluorophosphate, etc.

Sulfonium salts include triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrakis(pentafluorophenyl)borate, diphenyl[4-(phenylthio)phenyl]sulfonium hexafluorophosphate, 4,4'-bis[diphenylsulfonio]diphenylsulfide bishexafluorophosphate, 4,4'-bis[di(β-hydroxyethoxy)phenylsulfonio]diphenylsulfide bishexafluoroantimonate, 4,4'-bis[di(β-hydroxyethoxy)phenylsulfonio]diphenylsulfide bishexafluorophosphate, 7-[di(p-toluyl)sulfonio]-2-isopropylthioxanthone hexafluoroantimonate, 7 -[di(p-toluyl)sulfonio]-2-isopropylthioxanthone tetrakis(pentafluorophenyl)borate, 4-phenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide hexafluorophosphate, 4-(p-tert-butylphenylcarbonyl)-4'-diphenylsulfonio-diphenylsulfide hexafluoroantimonate, 4-(p-tert-butylphenylcarbonyl)-4'-di(p-toluyl)sulfonio-diphenylsulfide tetrakis(pentafluorophenyl)borate, tris[4-(4-acetylphenyl)sulfanylphenyl]sulfonium hexafluorophosphate, tris[4-(4-acetylphenyl)sulfanylphenyl]sulfonium tetrakis(pentafluorophenyl)borate, etc.

Anthraquinone derivatives include 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone, etc.

Thioxanthone derivatives include thioxanthone, 2-ethylthioxanthone, 4-ethylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 1-chloro-4-propoxythioxanthone, 1-methoxycarbonylthioxanthone, 2-ethoxycarbonylthioxanthone, etc.

Acridine derivatives include 9-phenylacridine, 9-(p-methoxyphenyl)acridine, 1,5-bis(9-acridinyl)pentane, 1,7-bis(9-acridinyl)heptane, etc.

Phenazine derivatives include 9,10-dimethylbenzphenazine, etc.

Anthrone derivatives include benzanthrone, etc.

Phenyl glyoxylate derivatives include methyl benzoyl formate, etc.

Ketosulfone derivatives include 1-[4-[(4-benzoylphenyl)thio]phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]-1-propanone, etc.

Organic peroxides include 3,3',4,4'-tetrakis(tert-butylperoxycarbonyl)benzophenone, 2-(1-tert-butylperoxy-1-methylethyl)-9H-thioxanthen-9-one, triazine peroxide derivatives, etc.

The photopolymerization initiator may be used alone or in combination with two or more types.

As the photopolymerization initiator, a commercially available product can also be used.
Examples of commercially available products include Omnicat (registered trademark, the same applies below) 250, Omnicat 270, Omnirad (registered trademark) 651, Omnirad 184, Omnirad 1173, Omnirad 2959, Omnirad 127, Omnirad 907, Omnirad 369, Omnirad 379EG, Omnirad TPO H, Omnirad 819, Omnirad 784, Omnirad MBF, Omnirad 754 (IGM Resins), IRGACURE (registered trademark) OXE01, IRGACURE OXE02, IRGACURE OXE03, IRGACURE OXE04, IRGACURE 290, IRGACURE 369 (manufactured by BASF); SEIKUOR (registered trademark) BZ, Z, and BEE (manufactured by Seiko Chemical Co., Ltd.); Kayacure (registered trademark) BP100, DETX-S; UVI-6992 (manufactured by The Dow Chemical Company); ADEKA Arcles (registered trademark) ARKLS) (registered trademark) SP-150, SP-152, and SP-170, N-1414, N-1717, N-1919, NCI-100, NCI-730, NCI-831, and NCI-930 (manufactured by ADEKA Corporation); TAZ-A, and TAZ-PP (manufactured by DKSH Japan Co., Ltd.); and TAZ-104 (manufactured by Sanyo Denki Co., Ltd. TRONLYTR-PBG-304, TRONLYTR-PBG-309, TRONLYTR-PBG-305, TRONLYTR-PBG-3057, TRONLYTR-PBG-314, TRONLYTR-PBG-326, TRONLYTR-PBG-345 (manufactured by Changzhou TRONLY NEW ELECTRONIC MATERIALS CO. LTD.); Perdual (registered trademark) TA-30G, TA-70H, TX (manufactured by NOF Corporation).

The content of the photopolymerization initiator in the composition for forming an anisotropic dye film of the present invention is preferably 0.1 parts by mass or more, and more preferably 0.5 parts by mass or more, relative to 100 parts by mass of the polymerizable liquid crystal compound, from the viewpoint of obtaining a sufficiently polymerized anisotropic dye film. Furthermore, from the viewpoint of preventing the orientation of the polymerizable liquid crystal compound from being disturbed, the content of the photopolymerization initiator is preferably 30 parts by mass or less, and more preferably 10 parts by mass or less, further preferably 8 parts by mass or less, and particularly preferably 3 parts by mass or less, relative to 100 parts by mass of the polymerizable liquid crystal compound.

The anisotropic dye film-forming composition of the present invention may contain a polymerization accelerator, a polymerization aid, etc., in order to use them in combination with the photopolymerization initiator as necessary.

The polymerization accelerators and polymerization aids used include, for example, amine compounds such as triethanolamine, N-methyldiethanolamine, ethyl-4-dimethylaminobenzoate, 2-(dimethylamino)ethyl benzoate, 2-ethylhexyl-4-dimethylaminobenzoate, octyl-4-dimethylaminobenzoate, and N-(2-hydroxyethyl)-N-methyl-p-toluidine; 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, and 2- Examples of mercapto compounds include mercapto compounds having a heterocyclic ring such as mercaptobenzimidazole; mercapto compounds such as aliphatic polyfunctional mercapto compounds such as pentaerythritol tetrakis(3-mercaptobutyrate), 1,4-bis(3-mercaptobutyryloxy)butane, 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, and trimellilolpropane tris(3-mercaptobutyrate).

The polymerization accelerator and polymerization aid may be used alone or in combination of two or more.

The anisotropic dye film-forming composition of the present invention may contain a sensitizing dye or other sensitizers, etc., for the purpose of increasing sensitivity, as necessary.

Sensitizing dyes that are appropriate for the wavelength of the exposure light source are used. For example, xanthene dyes described in JP-A-4-221958 and JP-A-4-219756; coumarin dyes having a heterocycle described in JP-A-3-239703 and JP-A-5-289335; 3-ketocoumarin dyes described in JP-A-3-239703 and JP-A-5-289335; pyrromethene dyes described in JP-A-6-19240; JP-A-47-2528 and JP-A-54-155292. , and dyes having a dialkylaminobenzene skeleton described in JP-B-37377, JP-A-48-84183, JP-A-52-112681, JP-A-58-15503, JP-A-60-88005, JP-A-59-56403, JP-A-2-69, JP-A-57-168088, JP-A-5-107761, JP-A-5-210240, and JP-A-4-288818.

Other sensitizers include the above-mentioned benzophenone derivatives and thioxanthone derivatives. Further sensitizers include anthracene derivatives, phenothiazine derivatives, perylene derivatives, etc.

Anthracene derivatives include anthracene, 9,10-diethoxyanthracene, 9,10-dibutoxyanthracene, etc.

Phenothiazine derivatives include phenothiazine, 10-methylphenothiazine, 10-phenylphenothiazine, 2-methoxyphenothiazine, 2-chlorophenothiazine, 2-acetylphenothiazine, etc.

Perylene derivatives include perylene, 2,5,8,11-tetra-tert-butylperylene, etc.

The sensitizing dyes and other sensitizers may be used alone or in combination of two or more.

<Other additives>
The anisotropic dye film-forming composition of the present invention may further contain, as necessary, a non-polymerizable liquid crystal compound, a thermal polymerization initiator, a polymerization inhibitor, a polymerization aid, a polymerizable non-liquid crystal compound, a non-polymerizable non-liquid crystal compound, a surfactant, a leveling agent, a coupling agent, a pH adjuster, a dispersant, an antioxidant, an organic or inorganic filler, an organic or inorganic nanosheet, an organic or inorganic nanofiber, a metal oxide, or the like.

<Solvent>
The anisotropic dye film-forming composition of the present invention may contain a solvent, if necessary.

The solvent that can be used is not particularly limited as long as it can sufficiently disperse or dissolve the polymerizable liquid crystal compound, the dye, and other additives in the composition for forming an anisotropic dye film. Examples of the solvent include alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate, and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane, and heptane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran, dimethoxyethane, ethylene glycol dimethyl ether, and ethylene glycol diethyl ether; fluorine-containing solvents such as perfluorobenzene, perfluorotoluene, perfluorodecalin, perfluoromethylcyclohexane, and hexafluoro-2-propanol; and chlorine-containing solvents such as chloroform, dichloromethane, chlorobenzene, and dichlorobenzene.
These solvents may be used alone or in combination of two or more.

The solvent is preferably one that can dissolve the polymerizable liquid crystal compound and the dye, and more preferably one that completely dissolves the polymerizable liquid crystal compound and the dye. In addition, the solvent is preferably one that is inactive in the polymerization reaction of the polymerizable liquid crystal compound. In addition, from the viewpoint of applying the anisotropic dye film-forming composition of the present invention as described below, a solvent having a boiling point in the range of 50 to 200°C is preferable.

When the anisotropic dye film-forming composition of the present invention contains a solvent, the content ratio of the solvent in the anisotropic dye film-forming composition of the present invention is preferably 50 to 98 mass % relative to the total amount (100 mass %) of the anisotropic dye film-forming composition of the present invention. In other words, the solid content in the anisotropic dye film-forming composition of the present invention is preferably 2 to 50 mass %.
When the solid content in the composition for forming an anisotropic dye film is equal to or less than the upper limit, the viscosity of the composition for forming an anisotropic dye film does not become too high, the thickness of the anisotropic dye film obtained becomes uniform, and unevenness in the anisotropic dye film tends to be less likely to occur.
The solid content of the composition for forming an anisotropic dye film can be determined taking into consideration the thickness of the anisotropic dye film to be produced.

<Viscosity of the composition for forming anisotropic dye film>
The viscosity of the anisotropic dye film-forming composition of the present invention is not particularly limited as long as a uniform film without thickness unevenness can be formed by the coating method described below. From the viewpoint of obtaining thickness uniformity over a large area, productivity such as coating speed, and in-plane uniformity of optical properties, the viscosity of the anisotropic dye film-forming composition of the present invention is preferably 0.1 mPa·s or more, and preferably 500 mPa·s or less, more preferably 100 mPa·s or less, and even more preferably 50 mPa·s or less.

<Method of producing anisotropic dye film-forming composition>
The method for producing the composition for forming an anisotropic dye film of the present invention is not particularly limited. For example, a dye, a polymerizable liquid crystal compound, a photopolymerization initiator, and optionally a solvent and other additives are mixed, and the mixture is stirred and shaken at 0 to 80° C. to dissolve the dye. If these are poorly soluble, a homogenizer, a bead mill disperser, or the like may be used.

The method for producing the anisotropic dye film-forming composition of the present invention may include a filtration step for the purpose of removing foreign matter, etc., from the composition.

The anisotropic dye film-forming composition of the present invention, when the solvent is removed from the anisotropic dye film-forming composition, may or may not be liquid crystal at any temperature, but it is preferable that the composition exhibits liquid crystallinity at any temperature.

The composition obtained by removing the solvent from the anisotropic dye film forming composition generally has an isotropic phase appearance temperature of less than 200°C, preferably less than 160°C, more preferably less than 140°C, even more preferably less than 115°C, even more preferably less than 110°C, and particularly preferably less than 105°C, from the viewpoint of the coating process described below.

[Method of manufacturing anisotropic dye film]
The anisotropic dye film of the present invention is preferably produced by a wet film-forming method using the anisotropic dye film-forming composition of the present invention.

The wet film-forming method referred to in this invention is a method in which an anisotropic dye film-forming composition is applied and oriented on a substrate by some method. Therefore, the anisotropic dye film-forming composition only needs to have fluidity, and may or may not contain a solvent. From the viewpoint of viscosity during application and film uniformity, it is preferable for the composition to contain a solvent.

The liquid crystal compounds and dyes in the anisotropic dye film may be oriented by shear during the coating process, or may be oriented during the drying process of the solvent. In addition, the liquid crystal compounds and dyes may be oriented and laminated on the substrate through a process of heating after coating and drying to re-align the liquid crystal compounds and dyes. In the wet film formation method, when the composition for forming an anisotropic dye film is applied to the substrate, the dyes and liquid crystal compounds self-associate (a molecular association state such as a liquid crystal state) already in the composition for forming an anisotropic dye film, or during the drying process of the solvent, or after the solvent has been completely removed, and orientation occurs in a small area. By applying an external field to this state, orientation can be achieved in a certain direction in a macroscopic region, and an anisotropic dye film with the desired performance can be obtained. In this respect, it differs from the method in which a polyvinyl alcohol (PVA) film or the like is dyed with a solution containing a dye and stretched, and the dye is oriented only in the stretching process. Here, the external field includes the influence of an orientation treatment layer previously applied to the substrate, shear force, magnetic field, electric field, heat, etc. These may be used alone or in combination. If necessary, a heating process may be performed.

The process of applying the anisotropic dye film-forming composition onto a substrate to form a film, the process of applying an external field to orient the film, and the process of drying the solvent may be performed sequentially or simultaneously.

In the wet film formation method, examples of methods for applying the composition for forming an anisotropic dye film onto a substrate include a coating method, a dip coating method, an LB film formation method, and a known printing method. There is also a method of transferring the anisotropic dye film thus obtained onto another substrate.

Among these, it is preferable to apply the composition for forming an anisotropic dye film onto the substrate using a coating method.

The orientation direction of the anisotropic dye film may be different from the coating direction. In the present invention, the orientation direction of the anisotropic dye film refers to, for example, the transmission axis (polarization axis) or absorption axis of polarized light in the case of a polarizing film. In the case of a retardation film, the orientation direction refers to the fast axis or slow axis.

The method of applying the composition for forming an anisotropic dye film to obtain an anisotropic dye film is not particularly limited, but examples include the method described in "Coating Engineering" by Harasaki Yuji (published by Asakura Publishing Co., Ltd. on March 20, 1971) on pages 253-277, the method described in "Creation and Application of Molecular Cooperative Materials" edited by Ichimura Kunihiro (published by CMC Publishing Co., Ltd. on March 3, 1998) on pages 118-149, and the method of applying the composition to a substrate having a stepped structure (which may be pre-treated for orientation) by slot die coating, spin coating, spray coating, bar coating, roll coating, blade coating, curtain coating, fountain coating, dip coating, etc. Among these, the slot die coating and bar coating methods are preferred because they can obtain a highly uniform anisotropic dye film.

The die coater used in the slot die coating method is generally equipped with a coating machine that ejects the coating liquid, a so-called slit die. Slit dies are disclosed, for example, in JP-A-2-164480, JP-A-6-154687, JP-A-9-131559, "Fundamentals and Applications of Dispersion, Coating, and Drying" (2014, Techno System Co., Ltd., ISBN 9784924728707 C 305), "Wet Coating Technology for Displays and Optical Components" (2007, Information Organization, ISBN 9784901677752), and "Precision Coating and Drying Technology in the Electronics Field" (2007, Technical Information Association, ISBN 9784861041389). These known slit dies can be used to coat flexible materials such as films and tapes, as well as hard materials such as glass substrates.

Substrates used in the formation of the anisotropic dye film of the present invention include glass, triacetate, acrylic, polyester, polyimide, polyetherimide, polyetheretherketone, polycarbonate, cycloolefin polymer, polyolefin, polyvinyl chloride, triacetyl cellulose, or urethane-based films.

In order to control the orientation direction of the dye, the substrate surface may be subjected to an orientation treatment (orientation film) by a known method (rubbing method, method of forming grooves (fine groove structure) on the surface of the orientation film, method of using polarized ultraviolet light/polarized laser (photo-orientation method), orientation method by forming an LB film, orientation method by oblique deposition of inorganic material, etc.) described on pages 226-239 of "Liquid Crystal Handbook" (Maruzen Co., Ltd., published October 30, 2000). In particular, orientation treatment by rubbing method and photo-orientation method are preferred. Materials used in the rubbing method include polyvinyl alcohol (PVA), polyimide (PI), epoxy resin, acrylic resin, etc. Materials used in the photo-orientation method include polycinnamate, polyamic acid/polyimide, azobenzene, etc. When an orientation treatment layer is provided, it is thought that the liquid crystal compound and the dye are oriented by the influence of the orientation treatment of the orientation treatment layer and the shear force applied to the anisotropic dye film forming composition during application.

When applying the anisotropic dye film-forming composition, there are no particular limitations on the method or interval for supplying the anisotropic dye film-forming composition. If the operation for supplying the coating liquid becomes complicated, or the coating film thickness fluctuates when the coating liquid is started and stopped, it is desirable to apply the anisotropic dye film-forming composition while continuously supplying it when the anisotropic dye film is thin.

The speed at which the composition for forming an anisotropic dye film is applied is usually 0.001 m/min or more, preferably 0.01 m/min or more, more preferably 0.1 m/min or more, even more preferably 1.0 m/min or more, and particularly preferably 5.0 m/min or more. The speed at which the composition for forming an anisotropic dye film is applied is usually 400 m/min or less, preferably 200 m/min or less, more preferably 100 m/min or less, and even more preferably 50 m/min or less. By having the application speed in the above range, the anisotropy of the anisotropic dye film is obtained, and it tends to be possible to apply it uniformly.

The application temperature of the composition for forming anisotropic dye film is usually 0°C or higher and 100°C or lower, preferably 80°C or lower, and more preferably 60°C or lower.

The humidity during application of the anisotropic dye film forming composition is preferably 10% RH or higher, and preferably 80% RH or lower.

The anisotropic dye film may be subjected to an insolubilization treatment. Insolubilization refers to a treatment for reducing the solubility of a compound in the anisotropic dye film, thereby controlling the elution of the compound from the anisotropic dye film and increasing the stability of the film.
Specifically, film polymerization or overcoating is preferred from the standpoint of ease of post-processing and durability of the anisotropic dye film.

When polymerizing the film, the film in which the liquid crystal molecules and dye molecules are oriented is polymerized using light and/or radiation.

When polymerization is carried out using light or radiation, it is preferable to irradiate with active energy rays having a wavelength in the range of 190 to 450 nm.

The light source of the active energy ray having a wavelength of 190 to 450 nm is not particularly limited. Examples of the light source include lamp light sources such as xenon lamps, halogen lamps, tungsten lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, medium-pressure mercury lamps, low-pressure mercury lamps, carbon arcs, and fluorescent lamps; and laser light sources such as argon ion lasers, YAG lasers, excimer lasers, nitrogen lasers, helium cadmium lasers, and semiconductor lasers. When light of a specific wavelength is irradiated, an optical filter can also be used.
The exposure dose of the active energy rays is preferably from 1 to 100,000 J/ ^m2 , and more preferably from 10 to 10,000 J/ ^m2 .

Polymerization may be performed using light and/or radiation, but photopolymerization or a combination of photopolymerization and thermal polymerization is preferred because it shortens the film formation process time and requires simple equipment. When thermal polymerization is performed, it is preferred to perform it in the range of 50 to 200°C, and more preferably in the range of 60 to 150°C.

[Protective Layer]
The protective layer is a film for protecting the anisotropic dye film (for example, imparting or improving abrasion resistance, scratch resistance, stress relaxation resistance, chemical resistance, gas resistance, water resistance, and corrosion resistance), and preferably, the protective layer is a photocurable film.

The protective layer may also serve as an overcoat film having functions such as bleeding prevention (prevention of bleeding out of low molecular weight components), flattening, easy adhesion, release, and optical property adjustment. As long as the protective layer can exhibit the function of protecting the anisotropic film, there are no limitations on the lamination position with respect to the anisotropic dye film. From the viewpoint of effectively protecting the anisotropic dye film, the protective layer preferably has a laminated structure adjacent to the anisotropic dye film of the present invention, and more preferably has a laminated structure adjacent to the surface of the anisotropic dye film opposite the substrate.

The protective layer of the first invention is preferably formed using a composition for forming a protective layer, which will be described later.
The protective layer of the second invention is formed using a protective layer-forming composition containing a curable resin.
The protective layer of the third invention is formed using a composition for forming a protective layer, which contains a photocurable resin and will be described later.

The thickness of the protective layer of the present invention is preferably 0.1 μm or more, more preferably 0.3 μm or more, even more preferably 0.5 μm or more, and even more preferably 1 μm or more, from the viewpoint of increasing the mechanical strength and fully exerting the protective effect. Also, from the viewpoint of reducing the thickness of the obtained optically anisotropic laminate, the thickness of the protective layer of the present invention is preferably 175 μm or less, more preferably 120 μm or less, even more preferably 100 μm or less, even more preferably 80 μm or less, particularly preferably 60 μm or less, especially preferably 50 μm or less, most preferably 20 μm or less, and most preferably 10 μm or less.

From the viewpoint of suppressing deterioration of the protective layer due to light, the protective layer of the present invention preferably has a light transmittance at wavelengths of 380 nm or less of less than 50%, more preferably less than 30%, and even more preferably less than 20%. On the other hand, from the viewpoint of suppressing deterioration of optical elements due to light, the light transmittance at wavelengths of 400 nm or less is preferably less than 30%, more preferably less than 25%, even more preferably less than 22%, and especially preferably less than 20%.

From the viewpoint of visibility when used in an image display device, the protective layer of the present invention preferably has a light transmittance at a wavelength of 430 nm of 60% or more, more preferably 70% or more, even more preferably 75% or more, and particularly preferably 80% or more.

[Protective layer forming composition]
The protective layer forming composition used to form the protective layer of the first invention (hereinafter, sometimes referred to as the "protective layer forming composition of the first invention") preferably contains at least a photocurable resin, more preferably further contains a photopolymerization initiator, and may further contain other components.
The composition for forming the protective layer of the second invention used to form the protective layer of the second invention contains at least a curable resin, and preferably further contains a photopolymerization initiator, and may further contain other components.
The protective layer forming composition used to form the protective layer of the third invention (hereinafter, sometimes referred to as the "protective layer forming composition of the third invention") contains at least a photocurable silicone resin, preferably further contains a photopolymerization initiator, and may further contain other components.
Hereinafter, the "composition for forming a protective layer of the first invention," the "composition for forming a protective layer of the second invention," and the "composition for forming a protective layer of the third invention" may be collectively referred to as the "composition for forming a protective layer of the present invention."

<Curable Resin>
As the photocurable resin of the protective layer-forming composition of the first invention, various resins known in the art can be used, such as acrylic resin, polyester resin, urethane resin, polyvinyl resin, epoxy resin, silicone resin, vinyl acetate resin, fluorine-based resin, nitrile rubber, chloroprene rubber, and styrene-butadiene rubber.
The composition for forming a protective layer according to the first invention preferably contains a photocurable silicone resin as the photocurable resin.

As the curable resin of the protective layer-forming composition of the second invention, various resins known in the art can be used, such as acrylic resin, polyester resin, urethane resin, polyvinyl resin, epoxy resin, silicone resin, vinyl acetate resin, fluorine-based resin, nitrile rubber, chloroprene rubber, and styrene-butadiene rubber.
The composition for forming a protective layer according to the second invention preferably contains a photocurable resin as the curable resin, and more preferably contains a photocurable silicone resin.
The composition for forming a protective layer according to the third invention contains a photocurable silicone resin as the photocurable resin.

When the composition for forming a protective layer of the present invention contains a photocurable silicone resin, good curability can be obtained, and sufficient protective performance as a protective layer can be achieved.
The photocurable silicone resin will be described below.

<Photocurable silicone resin>
From the viewpoint of suppressing compatibility between the anisotropic dye layer and the protective layer and exhibiting good heat resistance without mixing the two layers even when heated, the photocurable silicone resin preferably contains a siloxane unit in the main chain skeleton, and more preferably contains a dimethylsiloxane unit.
The photocurable silicone resin preferably contains fluorine atoms, from the viewpoint of suppressing compatibility between the anisotropic dye layer and the protective layer, preventing the two layers from mixing even when heated, and exhibiting good heat resistance.

It is further preferable that the photocurable silicone resin used in the present invention has a siloxane unit represented by the following formula (B) from the viewpoint of suppressing compatibility between the anisotropic dye layer and the protective layer, preventing the two layers from mixing even when heated, and exhibiting good heat resistance.
( ^{R21R22R23SiO1} / ² ⁾ _n1 ₍ ^R24R25SiO2 / ² ) _n2 ( _R26SiO3 / ² ) _n3 ( _SiO4/ ₂ ) _n4 ( _O1 / ^2R27 ) _n5 (B)
(In the formula, R ²¹ to R ²⁶ each independently represent a monovalent aliphatic hydrocarbon group which may have a substituent, or a monovalent aromatic hydrocarbon group which may have a substituent, and any of R ²¹ to R ²⁶ has a polymerizable group as a substituent.
^R27 is a hydrogen atom or an alkyl group.
n1 to n5 each independently represent an average of 0 to 1, and the sum of n1, n2, n3 and n4 is 1.

In R ^to ^R , the monovalent aliphatic hydrocarbon group is preferably a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms. Examples include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, and a cyclohexyl group. When the alkyl group has an alkyl structure, it may have a linear or branched structure.
The monovalent aromatic hydrocarbon group is preferably a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms, such as a phenyl group, a tolyl group, a phenylethyl group, a xylyl group, and a naphthyl group.

In R ²⁷ , the alkyl group is preferably an alkyl group having a carbon number of 1 to 4. Examples include a methyl group, an ethyl group, a propyl group, and a butyl group, and the alkyl group may have a straight chain structure or a branched chain structure.

Examples of the polymerizable group possessed by any of R ²¹ to R ²⁶ include a (meth)acryloyl group, a (meth)acryloyloxy group, a (meth)acryloylamino group, a vinyl group, a vinyloxy group, an epoxy structure-containing group, a mercapto group, an isocyanate group, an ethynyl group, an ethynyloxy group, a 1,3-butadienyl group, a 1,3-butadienyloxy group, an oxiranyl group, an oxetanyl group, a glycidyl group, a glycidyloxy group, a styryl group, a styryloxy group, etc. Among these, the (meth)acryloyl group and the (meth)acryloyloxy group are preferred, and the (meth)acryloyloxy group is more preferred, since good curability can be obtained.

From the viewpoint of enabling the protective layer to exert its protective function, the siloxane units having a substituent containing a polymerizable group are preferably 0.01 mol% or more of the total siloxane units, more preferably 0.05 mol% or more, and even more preferably 0.1 mol% or more. From the viewpoint of avoiding deformation such as cure shrinkage, the siloxane units having a substituent containing a polymerizable group are preferably 95 mol% or less of the total siloxane units, more preferably 90 mol% or less, and even more preferably 85 mol% or less.

Examples of the substituent other than the polymerizable group ^that R to R may have include ^a fluorine atom, a chlorine atom, a bromine atom, a phenyl group, an amino functional group, a perfluoroalkyl group, a poly(hexafluoropropylene oxide) structure-containing group, and other substituents containing a fluorine atom. Among these, from the viewpoint of suppressing compatibility between the anisotropic dye layer and the protective layer, a fluorine atom or a substituent containing a fluorine atom is preferred, and a fluorine atom is more preferred.

The siloxane units having the fluorine atom or a substituent containing a fluorine atom of the formula (B) suppress the compatibility between the anisotropic dye layer and the protective layer, and from the viewpoint of exhibiting good heat resistance without mixing of the two layers even when heated, the content of the siloxane units is preferably 0.01 mol% or more, and more preferably 0.05 mol% or more, based on the total siloxane units. In addition, from the viewpoint of making it easier to provide other functional layers on the protective layer, the content of the siloxane units having the fluorine atom or a substituent containing a fluorine atom of the formula (B) is preferably 90 mol% or less, more preferably 80 mol% or less, and even more preferably 70 mol% or less, based on the total siloxane units.

In the first and third inventions, the dimethylsiloxane units preferably account for 0.5 mol % or more and 95 mol % or less, and more preferably 1 mol % or more and 90 mol % or less, of the total siloxane units.
In the second invention, the dimethylsiloxane unit preferably accounts for 0.5 mol % or more and 60 mol % or less, and more preferably 1 mol % or more and 50 mol % or less, of the total siloxane units.

As the photocurable silicone resin used in the photocurable silicone resin composition, a commercially available product can also be used.
A commercially available photocurable silicone resin that does not contain fluorine atoms is X-40-2761 (manufactured by Shin-Etsu Chemical Co., Ltd.), and a commercially available photocurable silicone resin that contains fluorine atoms is X-12-2430C (manufactured by Shin-Etsu Chemical Co., Ltd.).

The molecular weight M of the photocurable silicone resin used in the first and third inventions is preferably 5,000 or more, more preferably 10,000 or more, even more preferably 12,000 or more, particularly preferably 15,000 or more, preferably 500,000 or less, more preferably 300,000 or less, and even more preferably 100,000 or less. If the molecular weight M of the photocurable silicone resin is equal to or greater than the lower limit, the cure shrinkage can be reduced and the optical performance of the optically anisotropic laminate can be improved. On the other hand, if the molecular weight M of the photocurable silicone resin is equal to or less than the upper limit, film formation tends to be easier.

The molecular weight M of the photocurable silicone resin used in the second invention is preferably 1000 or more, more preferably 5000 or more, even more preferably 10,000 or more, particularly preferably 15,000 or more, preferably 500,000 or less, more preferably 300,000 or less, and even more preferably 100,000 or less. If the molecular weight M of the photocurable silicone resin is equal to or greater than the lower limit, the cure shrinkage can be reduced and the optical performance of the optically anisotropic laminate can be improved. On the other hand, if the molecular weight M of the photocurable silicone resin is equal to or less than the upper limit, film formation tends to be easier.

The molecular weight M of a resin such as a photocurable silicone resin can be determined using the dynamic viscosity value. Specific measurement conditions are shown in the examples below.

These curable silicone resins may be used alone or in combination of two or more.

The protective layer forming composition of the present invention may contain a photocurable resin other than a photocurable silicone resin as the photocurable resin or curable resin. Examples of photocurable resins other than a photocurable silicone resin include acrylic resins, which are excellent in terms of ease of introduction of curable carbon-carbon double bonds such as (meth)acryloyl groups.

By controlling the amount of curable carbon-carbon double bonds such as the (meth)acryloyl group, the degree of crosslinking can be controlled, making it easier to adjust the bleed-out of low molecular weight components. Furthermore, such photocurable resins also have excellent bending properties. This is presumably because the inclusion of an appropriate amount of crosslinking groups in the resin component makes it possible to achieve both flexibility and curability.

Curable functional groups contained in photocurable resins include active energy ray-curable functional groups such as carbon-carbon double bonds. Examples include (meth)acryloyl groups and vinyl ether compounds. Among these, (meth)acryloyl groups, and especially acryloyl groups, are preferred in terms of ease of introduction and reactivity.

The polymerization reaction of the resin raw materials is usually radical polymerization, and can be carried out under conventionally known conditions.

　Monomers that can be used in combination as raw materials include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, phenyl (meth)acrylate, methoxy (poly)ethylene glycol (meth)acrylate, methoxy (poly)propylene glycol (meth)acrylate, methoxy (poly)ethylene glycol (poly)propylene glycol (meth)acrylate, octoxy (poly)ethylene glycol (meth)acrylate, octoxy (poly)propylene glycol (meth)acrylate, Examples of such methacrylates include (meth)acrylates such as t-butyl (meth)acrylamide, octoxytetramethylene glycol (meth)acrylate, lauroxy (poly)ethylene glycol (meth)acrylate, and stearoxy (poly)ethylene glycol (meth)acrylate; acrylamides such as ethyl (meth)acrylamide, n-butyl (meth)acrylamide, i-butyl (meth)acrylamide, t-butyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-hydroxypropyl (meth)acrylamide, and N,N-dihydroxyethyl (meth)acrylamide; and styrene-based monomers such as styrene, p-chlorostyrene, and p-bromostyrene. These may be used alone or in combination of two or more.

Acrylic resins can be produced by radical polymerization using the above-mentioned raw vinyl monomers. The radical polymerization reaction is preferably carried out in an organic solvent in the presence of a radical polymerization initiator.

The content of the photocurable resin in the protective layer is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, based on 100% by mass of the protective layer, from the viewpoint of expressing the function of the protective layer or obtaining a smooth protective layer. The content of the photocurable resin in the protective layer is preferably 99.99% by mass or less, more preferably 99.9% by mass or less, based on 100% by mass of the protective layer.

Therefore, the content of the photocurable resin in the composition for forming a protective layer used for forming the protective layer is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, and even more preferably 70 parts by mass or more, relative to 100 parts by mass of the solid content of the composition for forming a protective layer, from the viewpoint of expressing the function of the protective layer or from the viewpoint of obtaining a smooth protective layer. Also, the content of the photocurable resin in the composition for forming a protective layer is preferably 99.99 parts by mass or less, more preferably 99.9 parts by mass or less, relative to 100 parts by mass of the solid content of the composition for forming a protective layer.
Here, the solid content in the composition for forming a protective layer corresponds to the total of all components other than the solvent in the composition for forming a protective layer, and corresponds to the mass of the protective layer formed by the composition for forming a protective layer.

The content of the photocurable silicone resin in the protective layer forming composition used to form the protective layer is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, and even more preferably 35 parts by mass or more, per 100 parts by mass of the solid content of the protective layer forming composition, from the viewpoint of expressing the function of the protective layer or obtaining a smooth protective layer. The content of the photocurable silicone resin is preferably 99.5 parts by mass or less, more preferably 99 parts by mass or less, per 100 parts by mass of the solid content of the protective layer forming composition.

<Photopolymerization initiator>
The composition for forming a protective layer of the present invention preferably contains a photopolymerization initiator.

The maximum absorption wavelength of the photopolymerization initiator contained in the protective layer forming composition of the present invention is preferably 300 nm or more, more preferably 320 nm or more, and even more preferably 340 nm or more. The maximum absorption wavelength of the photopolymerization initiator is preferably 450 nm or less, more preferably 430 nm or less, and even more preferably 410 nm or less. By being in this range, the photopolymerization reaction proceeds sufficiently, and there is an effect that a protective layer with a good degree of hardening can be obtained.
As the photopolymerization initiator, the photopolymerization initiators exemplified in the composition for forming an anisotropic dye film can be used.

From the viewpoint of obtaining a protective layer with a good degree of hardening, the content of the photopolymerization initiator in the protective layer is preferably 0.1% by mass or more, and more preferably 0.5% by mass or more, based on 100% by mass of the protective layer. The content of the photopolymerization initiator is preferably 30% by mass or less, more preferably 10% by mass or less, even more preferably 8% by mass or less, particularly preferably 5% by mass or less, and especially preferably 3% by mass or less, based on 100% by mass of the protective layer.

Therefore, from the viewpoint of obtaining a protective layer with a good degree of hardening, the content of the photopolymerization initiator in the protective layer forming composition used to form the protective layer is preferably 0.1 parts by mass or more, and more preferably 0.5 parts by mass or more, per 100 parts by mass of the solid content of the protective layer forming composition. Furthermore, the content of the photopolymerization initiator is preferably 30 parts by mass or less, more preferably 10 parts by mass or less, even more preferably 8 parts by mass or less, and particularly preferably 3 parts by mass or less, per 100 parts by mass of the solid content of the protective layer forming composition.

<Other ingredients>
The composition for forming a protective layer of the present invention may contain a polymerizable liquid crystal compound and the like in addition to a photocurable resin as a polymerizable component that is cured by photopolymerization.

As the polymerizable liquid crystal compound, various conventionally known polymerizable liquid crystal compounds can be used. For example, the polymerizable liquid crystal compounds mentioned in the above-mentioned anisotropic dye film forming composition are described on pages 408-410, 521-524, 562-563, etc. of "Liquid Crystal Handbook" (Maruzen Co., Ltd., published October 30, 2000).

The protective layer forming composition of the present invention may further contain a non-polymerizable resin, a non-polymerizable liquid crystal compound, a thermal polymerization initiator, a polymerization inhibitor, a polymerization aid, a surfactant, a leveling agent, a coupling agent, a pH adjuster, a dispersant, an antioxidant, an antistatic agent, an ultraviolet absorber, a light stabilizer, a thickener, an antifoaming agent, a dye, an organic or inorganic filler, an organic or inorganic nanosheet, an organic or inorganic nanofiber, a metal oxide, etc.

Examples of ultraviolet absorbers that may be contained in the protective layer-forming composition of the present invention include benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, triazine-based ultraviolet absorbers, salicylic acid-based ultraviolet absorbers, and cyanoacrylate-based ultraviolet absorbers. Among these, benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, and triazine-based ultraviolet absorbers are preferred from the viewpoint of the ease with which the ultraviolet absorption effect can be obtained. Among these, benzophenone-based ultraviolet absorbers are more preferred from the viewpoint of excellent yellowing resistance.

These UV absorbents can be used alone or in combination of two or more.

<Solvent>
The composition for forming a protective layer of the present invention may contain a solvent, if necessary.

There are no particular limitations on the solvent that can be used, so long as it can sufficiently disperse or dissolve the photocurable resin, photopolymerization initiator, and other components contained in the composition for forming the protective layer. Examples of the solvent include alcohol solvents such as water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate, and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane, and heptane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran, dimethoxyethane, ethylene glycol dimethyl ether, and ethylene glycol diethyl ether; fluorine-containing solvents such as perfluorobenzene, perfluorotoluene, perfluorodecalin, perfluoromethylcyclohexane, and hexafluoro-2-propanol; and chlorine-containing solvents such as chloroform, dichloromethane, chlorobenzene, and dichlorobenzene.

From the viewpoint of being able to provide sufficient protective function to the anisotropic dye film, preferred solvents are alcohol solvents such as water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, and propylene glycol monomethyl ether; and ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate, and ethyl lactate, and more preferred are alcohol solvents such as water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, and propylene glycol monomethyl ether.

Furthermore, from the viewpoint of compatibility with the anisotropic dye film, polar solvents are preferred as the solvent. Among polar solvents, polar solvents with a relative dielectric constant of 10 or more are more preferred, polar solvents with a relative dielectric constant of 15 or more are even more preferred, and polar solvents with a relative dielectric constant of 20 or more are particularly preferred.

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

From the viewpoint of applying the protective layer-forming composition, it is preferable for the solvent to have a boiling point in the range of 50 to 200°C.

When the composition for forming a protective layer of the present invention contains a solvent, the content ratio of the solvent in the composition for forming a protective layer of the present invention is preferably 50 to 98 mass % relative to the total amount (100 mass %) of the composition for forming a protective layer of the present invention. In other words, the content of the solid content in the composition for forming a protective layer of the present invention is preferably 2 to 50 mass %.
When the solid content in the composition for forming a protective layer is equal to or less than the upper limit, the viscosity of the composition for forming a protective layer does not become too high, the thickness of the obtained protective layer becomes uniform, and unevenness in the protective layer tends to be less likely to occur.
The solid content can be determined taking into consideration the thickness of the protective layer to be produced.

<Viscosity of the composition for forming the protective layer>
The viscosity of the protective layer forming composition of the present invention is not particularly limited as long as a uniform protective layer without thickness unevenness is formed. From the viewpoint of obtaining a thickness uniformity over a large area and productivity such as coating speed by the coating method described later, the viscosity of the protective layer forming composition of the present invention is preferably 0.1 mPa·s or more, preferably 500 mPa·s or less, more preferably 100 mPa·s or less, and even more preferably 50 mPa·s or less.

<Method of producing composition for forming protective layer>
The method for producing the composition for forming a protective layer of the present invention is not particularly limited. For example, a photocurable resin, a photopolymerization initiator, and optionally a solvent and other components are mixed. A filtration step may be included for the purpose of removing foreign matter from the composition.

[Method of manufacturing protective layer]
The method for producing the protective layer of the present invention is not particularly limited. For example, the protective layer may be produced by forming the composition for forming a protective layer of the present invention into a sheet or by a wet film-forming method.

The method of forming into a sheet as referred to in the present invention is a method in which the protective layer forming composition is formed into a molded body, for example a sheet body, by some method, and then irradiated with heat and/or active energy rays to harden the protective layer forming composition.

　Methods for forming into a sheet include known methods such as wet lamination, dry lamination, extrusion casting using a T-die, extrusion lamination, calendaring, inflation, injection molding, and liquid injection curing. Among these, the wet lamination, extrusion casting, and extrusion lamination methods are preferred.

The wet film-forming method referred to in the present invention is a method in which the composition for forming a protective layer is applied to a substrate by some method, and then the composition for forming a protective layer is cured by polymerization using active energy rays. Thermal polymerization may be used in combination with polymerization using active energy rays.

The substrate may be a substrate containing an anisotropic dye film, or a substrate not containing an anisotropic dye film. In the case of a substrate not containing an anisotropic dye film, the protective layer can be produced by transferring the protective layer forming composition applied to the substrate to a substrate containing an anisotropic dye film, or by transferring the anisotropic dye film applied to the substrate to a substrate containing a protective layer forming composition, and then curing the composition by irradiating it with active energy rays.

Methods for applying the protective layer-forming composition of the present invention onto a substrate include, for example, reverse coating, gravure coating, rod coating, bar coating, Mayer bar coating, die coating, spray coating, etc.

The composition for forming a protective layer of the present invention may be dried at 30° C. or more and 150° C. or less, if necessary, before being polymerized by irradiation with active energy rays.
The active energy rays include light and radiation, of which ultraviolet light and visible light are preferred from the viewpoint of easy polymerization control.

When curing by ultraviolet irradiation, a xenon lamp, a high pressure mercury lamp, a metal halide lamp, an LED-UV lamp, or the like can be used as the light source of the ultraviolet irradiation device. The amount of ultraviolet irradiation is appropriately determined depending on the composition for forming a protective layer, but is usually 10 mJ/cm ² or more and 10,000 mJ/cm ² or less. From the viewpoint of the degree of curing, the amount of ultraviolet irradiation is preferably 15 mJ/cm ² or more and 5,000 mJ/cm ² or less, and more preferably 20 mJ/cm ² or more and 3,000 mJ/cm ² or less.

[Other functional films]
In addition to the anisotropic dye film and protective layer, the optically anisotropic laminate of the present invention may have a functional film such as a pressure-sensitive adhesive film having tackiness and/or adhesion, an antireflection film, a retardation film, a light control film that absorbs, reflects or scatters light, a low refractive film, a high refractive film, an electrically insulating film, an electrically conductive film, an alignment film, etc. These functional films are preferably photocurable films having photopolymerizability, but may also be films having no photopolymerizability.
Among these, a pressure-sensitive adhesive film is preferred from the viewpoint of facilitating the formation of an optical element using the optically anisotropic laminate.
The optically anisotropic laminate having a tacky adhesive film and a protective layer preferably has a laminate structure of anisotropic dye film/protective layer/tacky adhesive film. Other layers may be laminated between the anisotropic dye film, the protective layer and the tacky adhesive film.

(Adhesive film)
The adhesive film can be produced using a composition for forming an adhesive film.

From the viewpoint of suppressing deterioration of the adhesive film due to light, the adhesive film preferably has a light transmittance at wavelengths of 380 nm or less of less than 50%, more preferably less than 30%, and even more preferably less than 20%. On the other hand, from the viewpoint of suppressing deterioration of optical elements due to light, the adhesive film preferably has a light transmittance at wavelengths of 400 nm or less of less than 30%, more preferably less than 25%, even more preferably less than 22%, and especially preferably less than 20%.

In addition, from the viewpoint of visibility when used in an image display device, the adhesive film preferably has a light transmittance at a wavelength of 430 nm of 60% or more, more preferably 70% or more, even more preferably 75% or more, and particularly preferably 80% or more.

The thickness of the adhesive film is preferably 3 μm or more from the viewpoint of ensuring adhesiveness, more preferably 10 μm or more, even more preferably 20 μm or more, particularly preferably 30 μm or more, and especially preferably 40 μm or more. On the other hand, the upper limit of the thickness of the adhesive film is preferably 175 μm or less from the viewpoint of contributing to the thinning of the optically anisotropic laminate, more preferably 120 μm or less, even more preferably 80 μm or less, and especially preferably 60 μm or less.

The adhesive film-forming composition contains a curable resin and a photopolymerization initiator. The photopolymerization initiator of the adhesive film-forming composition can be any of the photopolymerization initiators listed for the protective layer-forming composition.

The content of the photopolymerization initiator in the composition for forming a tacky adhesive film is not particularly limited. From the viewpoint of sufficiently progressing the polymerization reaction and improving the shape stability of the tacky adhesive film, the content of the photopolymerization initiator in the composition for forming a tacky adhesive film is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 1 part by mass or more, and particularly preferably 2 parts by mass or more, relative to 100 parts by mass of the curable resin. In addition, the upper limit of the content of the photopolymerization initiator in the composition for forming a tacky adhesive film is preferably 15 parts by mass or less, more preferably 10 parts by mass or less, even more preferably 6 parts by mass or less, and particularly preferably 4 parts by mass or less, relative to 100 parts by mass of the curable resin, from the viewpoint of ensuring adhesion.

The curable resin contained in the adhesive film-forming composition has adhesive and/or bonding properties. As the curable resin, various resins that are conventionally known can be used. Examples include acrylic resin, epoxy resin, urethane resin, silicone resin, vinyl acetate resin, nitrile rubber, chloroprene rubber, and styrene butadiene rubber. Among these, acrylic resin is preferred because of its excellent adhesive properties.

The adhesive film may contain an ultraviolet absorbing agent. By containing an ultraviolet absorbing agent, deterioration of the optically anisotropic laminate caused by light can be reduced.
As the ultraviolet absorbing agent, the ultraviolet absorbing agents exemplified in the composition for forming the protective layer can be used.

[Method for producing optically anisotropic laminate]
The method for producing the optically anisotropic laminate of the present invention is not particularly limited, but the following methods (1) to (4) can be mentioned.
(1) A method for producing an optically anisotropic laminate by applying a composition for forming a protective layer to a substrate on which an anisotropic dye film has been formed, and polymerizing the composition using active energy rays to form a protective layer. (2) A method for producing an optically anisotropic laminate by forming a composition for forming a protective layer in a sheet form on a substrate on which an anisotropic dye film has been formed, and polymerizing the composition using active energy rays to form a protective layer. (3) A method for producing an optically anisotropic laminate by transferring a composition for forming a protective layer that has been applied to a substrate on which an anisotropic dye film has not been formed, or formed into a sheet form, to a substrate on which an anisotropic dye film has been formed, and then curing the composition using active energy rays to form a protective layer. (4) A method for producing an optically anisotropic laminate by transferring an anisotropic dye film from a substrate on which an anisotropic dye film has been formed to a composition for forming a protective layer that has been applied to a substrate on which an anisotropic dye film has not been formed, or formed into a sheet form, and then curing the composition using active energy rays to form a protective layer.

From the viewpoint of shortening the process, a method of producing an optically anisotropic laminate is preferred in which a composition for forming a protective layer is applied or formed into a sheet on a substrate on which an anisotropic dye film has been produced, and then polymerized using active energy rays to form a protective layer.
Functional films other than the protective layer can be formed in the same manner as the protective layer.

[Optical elements]
The optical element of the present invention includes the optically anisotropic laminate of the present invention.

In the present invention, the optical element refers to a polarizing element that utilizes the anisotropy of light absorption to obtain linearly polarized light, circularly polarized light, elliptically polarized light, etc., a phase difference element, an optical compensation element, and an element that has functions such as reflection, brightness improvement, refractive anisotropy, and conductive anisotropy. An optical element may have one or more functions. These functions can be appropriately adjusted by selecting the anisotropic dye film formation process and the composition containing the substrate and organic compound (dye or transparent material).

The optical element of the present invention is preferably used as a polarizing element or a polarizing element combined with other functions, and is more preferably used as a polarizing element.
The optical element of the present invention can be suitably used for applications such as flexible displays because a polarizing element can be obtained by forming an anisotropic dye film on a substrate by coating or the like.

[Polarizing element]
When the optical element of the present invention is used as a polarizing element, the polarizing element may have any other layer as long as it has the optically anisotropic laminate of the present invention.

The layers that can be used in combination with the polarizing element can be provided appropriately in accordance with the manufacturing process, characteristics, and functions, and the positions and order of lamination thereof are not particularly limited.
The layer having an optical function can be formed by the following method.

The layer that functions as a retardation film can be formed by coating or laminating a retardation film onto other layers that make up the polarizing element. The retardation film can be formed, for example, by carrying out the stretching treatment described in JP-A-2-59703 and JP-A-4-230704, or the treatment described in JP-A-7-230007.

The layer that functions as a brightness enhancement film can be formed by coating or laminating the brightness enhancement film onto other layers that make up the polarizing element. The brightness enhancement film can be formed, for example, by forming micropores using the methods described in JP-A-2002-169025 and JP-A-2003-29030, or by superimposing two or more cholesteric liquid crystal layers that have different central wavelengths of selective reflection.

A layer that functions as a reflective film or semi-transparent reflective film can be formed, for example, by coating or laminating a thin metal film obtained by vapor deposition or sputtering onto other layers that make up the polarizing element.

The layer that functions as a diffusion film can be formed, for example, by coating the other layers that make up the polarizing element with a resin solution that contains fine particles.

When the optical element of the present invention is used in various display elements such as LCDs and OLEDs, the optical element of the present invention may be formed directly on the surface of the electrode substrate or the like that constitutes these display elements, or the optical element of the present invention may be used as a component of these display elements.

The present invention will be described in more detail below with reference to examples. The present invention is not limited to the following examples as long as it does not depart from the gist of the present invention.
In the following description, "parts" means "parts by mass".

[Measurement and evaluation method]
Various measurement and evaluation methods in the following examples and comparative examples are as follows.

<Molecular weight M>
The kinetic viscosity η of the silicone resin was substituted into the A. J. Barry formula (the following formula (4)) to determine the molecular weight M of dimethylsiloxane. (Reference: A. J. Barry, J. Appl. physics, 17, 1020, [1946])
log η = 1.00 + 0.0123M ^0.5 (4)
When calculating the kinetic viscosity η from the viscosity μ, the following formula (5) is used (density: ρ).
η = μ / ρ (5)

<Surface free energy>
The surface free energy γ can be calculated by determining the static contact angle of water or diiodomethane at 25° C. with respect to the target surface and using the theoretical formula described in D. K. Owens and R. C. Wendt, J. Appl. Polym. Sci., 13, 1741 (1969).
The static contact angle was measured using a contact angle meter "DropMaster 500" manufactured by Kyowa Interface Science Co., Ltd. The measurement temperature was 25°C, the amount of droplet was 2 μL, and the contact angles of distilled water and diiodomethane were evaluated 1 second after the droplet landed. Five points were measured for each and the average value was calculated. The surface free energy was calculated using the theoretical formula described in the above non-patent document using the average static contact angle calculated.
γ ^d represents the dispersion component (dispersion term) of the surface free energy, and γ ^h represents the polar component (polar term) of the surface free energy.

<Heat resistance evaluation>
In the heat resistance test, the optically anisotropic laminate was heated on a hot plate at 80° C. for 5 minutes, and then removed from the hot plate and placed in a room temperature environment. The appearance of the optically anisotropic laminate after the test was observed and evaluated according to the following criteria.
(Evaluation criteria)
A: Good appearance was maintained.
×: Cloudiness was observed.

<Solvent resistance evaluation>
In a solvent resistance (ethanol) test, ethanol was dropped onto the optically anisotropic laminate, and one minute later, the laminate was wiped off with a cotton swab. After the test, the appearance of the optically anisotropic laminate was observed and evaluated according to the following criteria.
(Evaluation criteria)
A: Good appearance was maintained.
×: Traces of the cotton swab were observed.

[Polymerizable liquid crystal compounds/dyes]
Details of the polymerizable liquid crystal compounds and dyes contained in the anisotropic dye films used in the following Examples and Comparative Examples are as follows.

[Polymerizable Liquid Crystal Compound]
A polymerizable liquid crystal compound (I-1) (molecular weight: 828) represented by the following structural formula was synthesized according to the description of JP2020-042305A. In the following structural formula, _C11H22 means that 11 _methylene chains are bonded in a linear chain.

<Dye>
The chemical structures of the dyes (II-1) and (II-2) are shown below.

[Examples of the first invention and comparative examples]
[Example I-1]
<Preparation of composition for forming anisotropic dye film>
To 69.31 parts of cyclopentanone, 28.57 parts of polymerizable liquid crystal compound (I-1), 0.34 parts of dye (II-1) (manufactured by Hayashibara Co., Ltd.), 0.84 parts of dye (II-2) (manufactured by Showa Kako Co., Ltd.), 0.29 parts of IRGACURE (registered trademark) 369 (manufactured by BASF) (maximum absorption wavelength 319 nm), and 0.34 parts of BYK-361N (manufactured by BYK-Chemie) were added, and the mixture was heated and stirred at 80° C., and then filtered using a syringe equipped with a syringe filter (manufactured by Membrane Solutions, PTFE13045, aperture 0.45 μm) to obtain a composition for forming an anisotropic dye film.

<Formation of anisotropic dye film>
The composition for forming an anisotropic dye film was applied by spin coating to a substrate on which a polyimide alignment film (LX1400, Hitachi Chemical DuPont Microsystems, the alignment film was formed by rubbing) had been formed on glass. The substrate was then dried by heating at 120°C for 2 minutes, cooled to the liquid crystal phase, and polymerized at an exposure dose of 500 mJ/ ^cm2 (based on 365 nm) to obtain an anisotropic dye film with a thickness of 3 μm.
When the obtained anisotropic dye film was observed by holding a polarizing plate over the anisotropic dye film, clear light and dark appeared every time the polarizing plate was rotated by 90 degrees, indicating that the film had good polarizing performance.
The surface free energy measured for this anisotropic dye film is shown in Table 1 below.

<Preparation of protective layer forming composition>
As the photocurable silicone resin, the following fluorine-containing photocurable silicone resin X-12-2430C (manufactured by Shin-Etsu Chemical Co., Ltd.) (R-1) was used. This fluorine-containing photocurable silicone resin has a molecular weight M of 24,000.

40 parts of fluorine-containing photocurable silicone resin (R-1), 0.40 parts of photopolymerization initiator Omnirad 369 (manufactured by IGMRESINS), 1.20 parts of BYK-3550 (manufactured by BYK-Chemie), and 60 parts of ethanol were mixed and stirred, and filtered using a syringe equipped with a syringe filter (manufactured by Membrane Solutions, PTFE13045, aperture 0.45 μm) to obtain protective layer forming composition I-1.

<Formation of protective layer>
The protective layer-forming composition I-1 was applied onto the anisotropic dye film by spin coating, and the film was dried by heating at 50°C for 2 minutes. The film was then polymerized at an exposure dose of 500 mj/ ^cm2 (based on 365 nm) to form a protective layer I-1 having a thickness of 2 μm, thereby obtaining an optically anisotropic laminate I-1.
The surface free energy of the protective layer I-1 thus formed is shown in Table 1.

[Example I-2]
A protective layer I-2 was formed on the anisotropic dye film formed in the same manner as in Example I-1, except that the amount of the fluorine-containing photocurable silicone resin (R-1) was changed from 40 parts to 50 parts, and the amount of the photopolymerization initiator Omnirad 369 was changed from 0.40 parts to 0.50 parts, to obtain an optically anisotropic laminate I-2. The surface free energy of the protective layer I-2 formed was as shown in Table 1.

[Example I-3]
A protective layer I-3 was formed on the anisotropic dye film in the same manner as in Example I-1, except that fluorine-free photocurable silicone resin X-40-2761 (manufactured by Shin-Etsu Chemical Co., Ltd.) (R-2) was used as the photocurable silicone resin of the protective layer-forming composition, to obtain an optically anisotropic laminate I-3. The molecular weight M of this fluorine-free photocurable silicone resin (R-2) is 19,000. The surface free energy of the formed protective layer I-3 is as shown in Table 1.

[Comparative Example I-1]
A protective layer I-4 was formed on the anisotropic dye film in the same manner as in Example I-1, except that the following photocurable urethane acrylate resin Shikoh UV-7600B (manufactured by Mitsubishi Chemical Corporation) (R-3) was used as the photocurable resin of the protective layer-forming composition, to obtain an optically anisotropic laminate I-4. The weight average molecular weight (Mw) of this photocurable urethane acrylate resin (R-3) was 2000. The surface free energy of the formed protective layer I-4 was as shown in Table 1.

[Evaluation results]
The optically anisotropic laminates I-1 to I-4 produced in Examples I-1 to I-3 and Comparative Example I-1 were evaluated for heat resistance and solvent resistance. The results are shown in Table 1.

From Table 1, it can be seen that the optically anisotropic laminate of the first invention, in which the absolute value of the surface free energy difference between the anisotropic dye layer and the protective layer is 3 mN/ ^m2 or more, is excellent in heat resistance and solvent resistance, and can maintain good appearance and performance in applications such as polarizers.

[Examples of the second invention and comparative examples]
[Example II-1]
<Preparation of composition for forming anisotropic dye film>
To 69.31 parts of cyclopentanone, 28.57 parts of polymerizable liquid crystal compound (I-1), 0.34 parts of dye (II-1) (manufactured by Hayashibara Co., Ltd.), 0.84 parts of dye (II-2) (manufactured by Showa Kako Co., Ltd.), 0.29 parts of IRGACURE (registered trademark) 369 (manufactured by BASF) (maximum absorption wavelength 319 nm), and 0.34 parts of BYK-361N (manufactured by BYK-Chemie) were added, and the mixture was heated and stirred at 80° C., and then filtered using a syringe equipped with a syringe filter (manufactured by Membrane Solutions, PTFE13045, aperture 0.45 μm) to obtain a composition for forming an anisotropic dye film.

<Formation of anisotropic dye film>
The composition for forming an anisotropic dye film was applied by spin coating to a substrate on which a polyimide alignment film (LX1400, Hitachi Chemical DuPont Microsystems, the alignment film was formed by rubbing) had been formed on glass. The substrate was then dried by heating at 120°C for 2 minutes, cooled to the liquid crystal phase, and polymerized at an exposure dose of 500 mJ/ ^cm2 (based on 365 nm) to obtain an anisotropic dye film with a thickness of 3 μm.
When the obtained anisotropic dye film was observed by holding a polarizing plate over the anisotropic dye film, clear light and dark appeared every time the polarizing plate was rotated by 90 degrees, indicating that the film had good polarizing performance.

40 parts of fluorine-containing photocurable silicone resin (R-1), 0.40 parts of photopolymerization initiator Omnirad 369 (manufactured by IGMRESINS), 1.20 parts of BYK-3550 (manufactured by BYK-Chemie), and 60 parts of ethanol were mixed and stirred, and filtered using a syringe equipped with a syringe filter (manufactured by Membrane Solutions, PTFE13045, aperture 0.45 μm) to obtain protective layer forming composition II-1.

<Formation of protective layer>
The protective layer-forming composition II-1 was applied onto the anisotropic dye film by spin coating, and the film was dried by heating at 50°C for 2 minutes. The film was then polymerized at an exposure dose of 500 mj/ ^cm2 (based on 365 nm) to form a protective layer II-1 having a thickness of 2 μm, thereby obtaining an optically anisotropic laminate II-1.

<Surface Free Energy of Film Obtained by Curing Resin Contained in Composition for Forming Protective Layer>
The R-1 resin-containing composition obtained in the same manner as in protective layer-forming composition II-1, except that 1.20 parts of BYK-3550 was changed to 0 parts, was formed into a film on glass by spin coating, and the film was dried by heating at 50°C for 2 minutes, and then polymerized at an exposure dose of 500 mj/ ^cm2 (based on 365 nm) to obtain an R-1 resin layer. The surface free energy of the fluorine-containing photocurable silicone resin (R-1) was determined as the surface free energy of the R-1 resin layer, and is shown in Table 2.

[Example II-2]
A protective layer II-2 was formed on the anisotropic dye film formed in the same manner as in Example II-1, except that the amount of the fluorine-containing photocurable silicone resin (R-1) was changed from 40 parts to 50 parts, and the amount of the photopolymerization initiator Omnirad 369 was changed from 0.40 parts to 0.50 parts, to obtain an optically anisotropic laminate II-2.

[Example II-3]
A protective layer II-3 was formed on the anisotropic dye film in the same manner as in Example II-1, except that a fluorine-free photocurable silicone resin X-40-2761 (manufactured by Shin-Etsu Chemical Co., Ltd.) (R-2) was used as the photocurable silicone resin of the protective layer-forming composition, to obtain an optically anisotropic laminate II-3. The molecular weight M of this fluorine-free photocurable silicone resin (R-2) is 19,000.
The R-2 resin layer was obtained in the same manner as in Example II-1, except that the photocurable silicone resin (R-1) was replaced with the fluorine-free photocurable silicone resin (R-2). The surface free energy of the fluorine-free photocurable silicone resin (R-2) was determined as the surface free energy of the R-2 resin layer, and is shown in Table 2.

[Comparative Example II-1]
A protective layer II-4 was formed on the anisotropic dye film in the same manner as in Example II-1, except that the photocurable urethane acrylate resin Shikoh UV-7600B (manufactured by Mitsubishi Chemical Corporation) (R-3) was used as the photocurable resin of the protective layer-forming composition, to obtain an optically anisotropic laminate II-4. The weight average molecular weight (Mw) of this photocurable urethane acrylate resin (R-3) is 2000.
The R-3 resin layer was obtained in the same manner as in Example II-1, except that the photocurable silicone resin (R-1) was replaced with the photocurable urethane acrylate resin (R-3). The surface free energy of the photocurable urethane acrylate resin (R-3) was determined as the surface free energy of the R-3 resin layer, and is shown in Table 2.

[Evaluation results]
The optically anisotropic laminates II-1 to II-4 produced in Examples II-1 to II-3 and Comparative Example II-1 were evaluated for heat resistance and solvent resistance. The results are shown in Table 2.

From Table 2, it can be seen that the optically anisotropic laminate of the second invention, in which the surface free energy of the film obtained by curing the curable resin contained in the composition for forming a protective layer is 45 mN/ ^m2 or less, has excellent heat resistance and solvent resistance, and can maintain good appearance and performance in applications such as polarizers.

[Examples of the third invention and comparative examples]
[Example III-1]
<Preparation of composition for forming anisotropic dye film>
To 69.31 parts of cyclopentanone, 28.57 parts of polymerizable liquid crystal compound (I-1), 0.34 parts of dye (II-1) (manufactured by Hayashibara Co., Ltd.), 0.84 parts of dye (II-2) (manufactured by Showa Kako Co., Ltd.), 0.29 parts of IRGACURE (registered trademark) 369 (manufactured by BASF) (maximum absorption wavelength 319 nm), and 0.34 parts of BYK-361N (manufactured by BYK-Chemie) were added, and the mixture was heated and stirred at 80° C., and then filtered using a syringe equipped with a syringe filter (manufactured by Membrane Solutions, PTFE13045, aperture 0.45 μm) to obtain a composition for forming an anisotropic dye film.

40 parts of fluorine-containing photocurable silicone resin (R-1), 0.40 parts of photopolymerization initiator Omnirad 369 (manufactured by IGMRESINS), 1.20 parts of BYK-3550 (manufactured by BYK-Chemie), and 60 parts of ethanol were mixed and stirred, and filtered using a syringe equipped with a syringe filter (manufactured by Membrane Solutions, PTFE13045, aperture 0.45 μm) to obtain protective layer forming composition III-1.

<Formation of protective layer>
The protective layer-forming composition III-1 was applied onto the anisotropic dye film by spin coating, and the film was dried by heating at 50°C for 2 minutes. The film was then polymerized at an exposure dose of 500 mj/ ^cm2 (based on 365 nm) to form a protective layer III-1 having a thickness of 2 μm, thereby obtaining an optically anisotropic laminate III-1.

[Example III-2]
A protective layer III-2 was formed on the anisotropic dye film formed in the same manner as in Example III-1, except that the amount of the fluorine-containing photocurable silicone resin (R-1) was changed from 40 parts to 50 parts, and the amount of the photopolymerization initiator Omnirad 369 was changed from 0.40 parts to 0.50 parts, to obtain an optically anisotropic laminate III-2.

[Example III-3]
A protective layer III-3 was formed on the anisotropic dye film in the same manner as in Example III-1, except that a fluorine-free photocurable silicone resin X-40-2761 (manufactured by Shin-Etsu Chemical Co., Ltd.) (R-2) was used as the photocurable silicone resin of the protective layer-forming composition, to obtain an optically anisotropic laminate III-3. The molecular weight M of this fluorine-free photocurable silicone resin (R-2) is 19,000.

[Comparative Example III-1]
A protective layer III-4 was formed on the anisotropic dye film in the same manner as in Example III-1, except that the photocurable urethane acrylate resin SHIKO UV-7600B (manufactured by Mitsubishi Chemical Corporation) (R-3) was used as the photocurable resin of the protective layer-forming composition, to obtain an optically anisotropic laminate III-4. The weight average molecular weight (Mw) of this photocurable urethane acrylate resin (R-3) is 2000.

[Evaluation results]
The optically anisotropic laminates III-1 to III-4 produced in Examples III-1 to III-3 and Comparative Example III-1 were evaluated for heat resistance and solvent resistance. The results are shown in Table 3.

From Table 3, it can be seen that the optically anisotropic laminate of the third invention, in which the protective layer is formed from a protective layer-forming composition containing a photocurable silicone resin, has excellent heat resistance and solvent resistance, and can maintain good appearance and performance in applications such as polarizers.

Although the present invention has been described in detail using specific embodiments, it will be apparent to those skilled in the art that various modifications are possible within the scope of the invention.
This application is based on Japanese Patent Application No. 2022-153906, Japanese Patent Application No. 2022-153907, and Japanese Patent Application No. 2022-153908 filed on September 27, 2022, and is incorporated by reference in its entirety.

Claims

An optically anisotropic laminate in which a protective layer is laminated on an anisotropic dye layer,
the anisotropic dye layer is a layer formed from a composition for forming an anisotropic dye film, which contains a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator;
An optically anisotropic laminate, wherein the absolute value of the difference in surface free energy between the anisotropic dye layer and the protective layer is 3 mN/ m2 or more.
The optically anisotropic laminate according to claim 1, wherein the protective layer is a layer formed from a protective layer-forming composition containing a photocurable silicone resin.
The optically anisotropic laminate according to claim 2, wherein the photocurable silicone resin contains fluorine atoms.
The optically anisotropic laminate according to claim 1, wherein the polymerizable liquid crystal compound is a low molecular weight polymerizable liquid crystal compound that does not have a repeating structure.
2. The optically anisotropic laminate according to claim 1, wherein the polymerizable liquid crystal compound is a compound represented by the following formula (1):
Q 1 -R 1 -A 11 -Y 1 -A 12 -(Y 2 -A 13 ) k -R 2 -Q 2 ... (1)
(In formula (1),
-Q1 represents a hydrogen atom or a polymerizable group;
-Q2 represents a polymerizable group;
-R 1 - and -R 2 - each independently represent a chain organic group;
-A 11 - and -A 13 - each independently represent a partial structure represented by the following formula (2), a divalent organic group, or a single bond;
-A 12 - represents a partial structure represented by the following formula (2) or a divalent organic group;
Each of -Y 1 - and -Y 2 - independently represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C≡C-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -;
One of -A 11 - and -A 13 - is a partial structure represented by the following formula (2) or a divalent organic group:
k is 1 or 2.
When k is 2, two -Y 2 -A 13 - may be the same or different.
-Cy-X 2 -C≡C-X 1 - ... (2)
(In formula (2),
-Cy- represents a hydrocarbon ring group or a heterocyclic group;
-X 1 - represents -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -;
-X 2 - represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -.
An optically anisotropic laminate in which a protective layer is laminated on an anisotropic dye layer,
the anisotropic dye layer is a layer formed from a composition for forming an anisotropic dye film, which contains a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator;
the protective layer is a layer formed from a protective layer-forming composition containing a curable resin,
An optically anisotropic laminate, wherein the surface free energy of a film obtained by curing the curable resin is 45 mN/ m2 or less.
The optically anisotropic laminate according to claim 1, wherein the curable resin is a photocurable silicone resin.
The optically anisotropic laminate according to claim 2, wherein the photocurable silicone resin contains fluorine atoms.
The optically anisotropic laminate according to claim 1, wherein the polymerizable liquid crystal compound is a low molecular weight polymerizable liquid crystal compound that does not have a repeating structure.
2. The optically anisotropic laminate according to claim 1, wherein the polymerizable liquid crystal compound is a compound represented by the following formula (1):
Q 1 -R 1 -A 11 -Y 1 -A 12 -(Y 2 -A 13 ) k -R 2 -Q 2 ... (1)
(In formula (1),
-Q1 represents a hydrogen atom or a polymerizable group;
-Q2 represents a polymerizable group;
-R 1 - and -R 2 - each independently represent a chain organic group;
-A 11 - and -A 13 - each independently represent a partial structure represented by the following formula (2), a divalent organic group, or a single bond;
-A 12 - represents a partial structure represented by the following formula (2) or a divalent organic group;
Each of -Y 1 - and -Y 2 - independently represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C≡C-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -;
One of -A 11 - and -A 13 - is a partial structure represented by the following formula (2) or a divalent organic group:
k is 1 or 2.
When k is 2, two -Y 2 -A 13 - may be the same or different.
-Cy-X 2 -C≡C-X 1 - ... (2)
(In formula (2),
-Cy- represents a hydrocarbon ring group or a heterocyclic group;
-X 1 - represents -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -;
-X 2 - represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -.
An optically anisotropic laminate in which a protective layer is laminated on an anisotropic dye layer,
the anisotropic dye layer is a layer formed from a composition for forming an anisotropic dye film, which contains a dye, a polymerizable liquid crystal compound, and a photopolymerization initiator;
the protective layer is a layer formed from a protective layer-forming composition containing a photocurable resin,
The optically anisotropic laminate, wherein the photocurable resin comprises a photocurable silicone resin.
The optically anisotropic laminate according to claim 1, wherein the molecular weight M of the photocurable silicone resin is 5000 or more.
The optically anisotropic laminate according to claim 1, wherein the photocurable silicone resin contains fluorine atoms.
The optically anisotropic laminate according to claim 1, wherein the polymerizable liquid crystal compound is a low molecular weight polymerizable liquid crystal compound that does not have a repeating structure.
2. The optically anisotropic laminate according to claim 1, wherein the polymerizable liquid crystal compound is a compound represented by the following formula (1):
Q 1 -R 1 -A 11 -Y 1 -A 12 -(Y 2 -A 13 ) k -R 2 -Q 2 ... (1)
(In formula (1),
-Q1 represents a hydrogen atom or a polymerizable group;
-Q2 represents a polymerizable group;
-R 1 - and -R 2 - each independently represent a chain organic group;
-A 11 - and -A 13 - each independently represent a partial structure represented by the following formula (2), a divalent organic group, or a single bond;
-A 12 - represents a partial structure represented by the following formula (2) or a divalent organic group;
Each of -Y 1 - and -Y 2 - independently represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C≡C-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -;
One of -A 11 - and -A 13 - is a partial structure represented by the following formula (2) or a divalent organic group:
k is 1 or 2.
When k is 2, two -Y 2 -A 13 - may be the same or different.
-Cy-X 2 -C≡C-X 1 - ... (2)
(In formula (2),
-Cy- represents a hydrocarbon ring group or a heterocyclic group;
-X 1 - represents -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -;
-X 2 - represents a single bond, -C(=O)O-, -OC(=O)-, -C(=S)O-, -OC(=S)-, -C(=O)S-, -SC(=O)-, -CH 2 CH 2 -, -CH=CH-, -C(=O)NH-, -NHC(=O)-, -CH 2 O-, -OCH 2 -, -CH 2 S-, or -SCH 2 -.
An optical element comprising the optically anisotropic laminate according to any one of claims 1 to 15.