JP7734006B2 - Compound, composition, film, laminate and display device - Google Patents

Description

The present invention relates to compounds, compositions, films, laminates, and display devices.

There is a continuing demand for thinner displays such as image display panels, and further thinner polarizing plates and polarizers, which are one of the components of such displays, are also being demanded. In response to this demand, for example, a thin host-guest polarizer has been proposed, which includes a polarizing film containing a polymerizable liquid crystal compound and a dye compound that exhibits dichroism (see, for example, Patent Documents 1 and 2).

Special Publication No. 2007-510946 JP 2013-37353 A

Further improvements in the dichroic ratio are required for host-guest polarizers. The object of the present invention is to provide a compound with a high dichroic ratio, a composition containing the compound, a film formed from the composition, a laminate including the film, and a light-emitting device including the laminate.

The present invention provides the following [1] to [12].
[1] A composition comprising a compound represented by the following formula (1) and a liquid crystal compound containing at least one of a polymerizable liquid crystal compound and a liquid crystalline polymer compound:
[In formula (1), n represents an integer of 1 or 2.
Ar ¹ , Ar ² and Ar ³ each independently represent a 1,4-phenylene group or a sulfur-containing heterocyclic group, each of which may have a substituent. At least one of Ar ¹ , Ar ² and Ar ³ has at least one hydroxyl group capable of forming an intramolecular hydrogen bond.
^R1 represents an alkylamino group which may have a polymerizable group.
When Ar ¹ does not have a hydroxyl group capable of forming an intramolecular hydrogen bond or has a hydroxyl group at the ortho position of the azo group, R ² represents at least one group selected from the group consisting of an alkanediyl group having 4 to 20 carbon atoms, an alkanediyloxy group having 2 to 20 carbon atoms, an alkanediyloxycarbonyl group having 2 to 20 carbon atoms, an alkanediylcarbonyl group having 2 to 20 carbon atoms, and an alkanediylcarbonyloxy group having 2 to 20 carbon atoms.
When Ar ¹ has a hydroxyl group capable of forming an intramolecular hydrogen bond at the ortho position of R ² , R ² represents a cyclic or chain group having 2 to 20 carbon atoms capable of forming a hydrogen bond with the hydroxyl group.

^R3 represents a polymerizable group or a hydrogen atom.
When n is 2, two Ar ^2s may be the same or different.
[2] The composition according to [1], wherein the polymerizable liquid crystal compound is a polymerizable smectic liquid crystal compound, and the liquid crystalline polymer compound is a smectic liquid crystalline polymer compound.
[3] The composition according to [1] or [2], wherein the polymerizable liquid crystal compound includes a compound represented by the following formula (A):
In formula (A), m represents an integer of 1 to 3.
^X1 , ^X2 , and ^X3 each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group. When m is 2 or 3, multiple ^X1s may be the same or different. At least three selected from the group consisting of ^X1 , ^X2 , and ^X3 represent a divalent 6-membered hydrocarbon ring group.
Y ¹ , Y ² , W ¹ and W ² each independently represent a single bond or a divalent linking group, and when m is 2 or 3, multiple Y ^{1 s} may be the same or different.
^V1 and ^V2 each independently represent an alkanediyl group having 1 to 20 carbon atoms which may have a substituent, in which at least one of _-CH2- constituting the alkanediyl group may be replaced by -O-, -CO-, -S- or -NH-.
^U1 and ^U2 each independently represent a polymerizable group or a hydrogen atom, and at least one of them represents a polymerizable group.
[4] The composition according to any one of [1] to [3], wherein the compound represented by formula (1) has one hydroxyl group capable of forming an intramolecular hydrogen bond.
[5] The composition according to any one of [1] to [4], wherein the compound represented by formula (1) has a hydroxyl group in Ar ¹ capable of forming an intramolecular hydrogen bond with R ³ , or a hydroxyl group in Ar ² capable of forming an intramolecular hydrogen bond with —N═N—.
[6] A compound represented by the following formula (1a):
In formula (1a), k represents an integer of 1 or 2.
Ar ¹¹ , Ar ¹² and Ar ¹³ each independently represent a 1,4-phenylene group or a sulfur-containing heterocyclic group which may have a substituent, and at least one of ^{Ar 11} and Ar ¹² has at least one hydroxyl group capable of forming an intramolecular hydrogen bond.
R ¹¹ represents an alkylamino group which may have a polymerizable group.
When Ar ¹¹ does not have a hydroxyl group capable of forming an intramolecular hydrogen bond or has a hydroxyl group at the ortho position of the azo group, R ¹² represents at least one group selected from the group consisting of an alkanediyl group having 4 to 20 carbon atoms, an alkanediyloxy group having 2 to 20 carbon atoms, an alkanediyloxycarbonyl group having 2 to 20 carbon atoms, an alkanediyloxycarbonyl group having 2 to 20 carbon atoms, and an alkanediylcarbonyloxy group having 2 to 20 carbon atoms.
When Ar ¹¹ has a hydroxyl group capable of forming an intramolecular hydrogen bond at the ortho position of R ¹² , R ¹² represents a cyclic or chain group having 2 to 20 carbon atoms capable of forming a hydrogen bond with the hydroxyl group.
R ¹³ represents a polymerizable group or a hydrogen atom.
When k is 2, two Ar ¹² may be the same or different.
[7] The compound according to [6], wherein the number of hydroxyl groups capable of forming an intramolecular hydrogen bond is 1.
[8] The compound according to [6] or [7], wherein Ar ¹¹ , Ar ¹² and Ar ¹³ are 1,4-phenylene groups which may have a substituent.
[9] The compound according to any one of [6] to [8], wherein Ar ¹¹ has a hydroxyl group capable of forming an intramolecular hydrogen bond with R ¹³ , or Ar ¹² has a hydroxyl group capable of forming an intramolecular hydrogen bond with —N═N—.
[10] A film formed from the composition according to any one of [1] to [5].
[11] A laminate comprising the film according to [10].
[12] A display device comprising the laminate according to [11].

The present invention provides a compound with a high dichroic ratio, a composition containing the compound, a film formed from the composition, a laminate including the film, and a light-emitting device including the laminate.

As used herein, the term "process" refers not only to an independent process, but also to processes that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved. Furthermore, when the composition contains multiple substances corresponding to each component, the content of each component in the composition refers to the total amount of those multiple substances present in the composition, unless otherwise specified. Furthermore, the upper and lower limits of the numerical ranges described in this specification can be arbitrarily selected and combined. Below, embodiments of the present invention are described in detail. The scope of the present invention is not limited to the embodiments described herein, and various modifications can be made without departing from the spirit of the present invention.

<Composition>
The composition according to this embodiment includes a compound represented by formula (1) and a liquid crystalline compound. The liquid crystalline compound includes at least one of a polymerizable liquid crystalline compound and a liquid crystalline polymer compound. The composition is used, for example, as a material for forming a polarizing film. That is, the composition may be a composition for forming a polarizing film. A polarizing plate including a polarizing film obtained using the composition as a forming material can exhibit a high dichroic ratio (DR).

In the compound represented by formula (1), at least one of Ar ¹ , Ar ² , and Ar ³ has at least one hydroxyl group capable of forming an intramolecular hydrogen bond, which increases the number of pseudo-rings due to the intramolecular hydrogen bond, thereby improving the interaction with the host compound, which is thought to result in an increase in the dichroic ratio (DR) of a polarizing film containing the compound represented by formula (1).

In formula (1), Ar ¹ , Ar ² and Ar ³ each independently represent a 1,4-phenylene group or a sulfur-containing heterocyclic group, which may have a substituent, preferably a 1,4-phenylene group, which may have a substituent. Examples of the divalent sulfur-containing heterocyclic group include a benzothiazolediyl group, a thienothiazolediyl group and a thiazolediyl group, and preferably a benzothiazolediyl group.

The substituents in Ar ¹ , Ar ² and Ar ³ may be at least one selected from the group consisting of a halogen atom, a hydroxyl group, a methyl group and a methoxy group, preferably a fluorine atom, a chlorine atom, a hydroxyl group, a methyl group or a methoxy group, more preferably a fluorine atom or a hydroxyl group. The number of substituents in Ar ¹ , Ar ² and Ar ³ is each independently, for example, 0, 1 or 2, preferably 0 or 1.

At least one of Ar ¹ , Ar ² , and Ar ³ has at least one hydroxyl group capable of forming an intramolecular hydrogen bond. The hydroxyl group capable of forming an intramolecular hydrogen bond is preferably present in at least one of Ar ¹ and Ar ² , and more preferably present in at least Ar ¹ .

Functional groups with which a hydroxyl group can form an intramolecular hydrogen bond may be adjacent to each other on the same ring. That is, it is preferable for a hydroxyl group to form an intramolecular hydrogen bond with a functional group located in its ortho position, and it is also preferable for a hydroxyl group to form an intramolecular hydrogen bond in a six-membered ring. Examples of functional groups with which a hydroxyl group can form an intramolecular hydrogen bond include hydroxyl, methoxy, azo, carbonyl, oxycarbonyl (-OC(=O)-), carbonyloxy (-C(=O)O-), 2-pyrrolidinediyl, 2-piperidinediyl, 2-pyrimidinediyl, 2-thiazolediyl, 2-thiazolinediyl, 2-oxazolediyl, and 2-oxazolinediyl. Functional groups with which a hydroxyl group can form an intramolecular hydrogen bond may be, for example, functional groups other than azo groups.

The compound represented by formula (1) preferably has a hydroxyl group capable of forming an intramolecular hydrogen bond in at least one of Ar ¹ and Ar ² , and the hydroxyl group forms an intramolecular hydrogen bond with at least one of ^the azo group connecting Ar ¹ and Ar 2 and R ² , and more preferably has a hydroxyl group capable of forming an intramolecular hydrogen bond in at least Ar ¹ , and the hydroxyl group forms an intramolecular hydrogen bond with R ^2. The number of hydroxyl groups capable of forming an intramolecular hydrogen bond in the compound represented by formula (1) may be, for example, 1. When the hydroxyl group forms an intramolecular hydrogen bond with ^R2 , ^R2 preferably contains -OC(=O)-, a carbonyl group, a 2-pyrrolidinediyl group, a 2-piperidinediyl group, a 2-pyrimidinediyl group, a 2-thiazolediyl group, a 2-thiazolinediyl group, a 2-oxazolediyl group, or a 2-oxazolinediyl group, more preferably contains at least -OC(=O)- or a carbonyl group, and further preferably is an alkanediyloxycarbonyl group having 2 to 20 carbon atoms or an alkanediylcarbonyl group having 2 to 20 carbon atoms.

^R1 represents an alkylamino group which may have a polymerizable group. The alkylamino group in ^R1 may be a monoalkylamino group or a dialkylamino group, preferably a dialkylamino group. Examples of the alkylamino group in ^R1 include a dimethylamino group, a diethylamino group, an ethylmethylamino group, a dipropylamino group, a diisopropylamino group, a monomethylamino group, a monoethylamino group, a monopropylamino group, a monoisopropylamino group, a pyrrolidyl group, a piperidyl group, a morpholinyl group, and an oxazolidinyl group, and may be at least one selected from the group consisting of these. The alkylamino group in ^R1 is preferably a dimethylamino group or a diethylamino group.

At least one hydrogen atom of the alkylamino group represented by ^R1 may be substituted with a polymerizable group. Examples of the polymerizable group include a (meth)acrylate group ((meth)acryloyloxy group), a vinylphenyl group, a vinyl group, and an epoxy group. The polymerizable group is preferably a radically polymerizable group, and a (meth)acrylate group is particularly preferred. When ^R1 has a polymerizable group, the number thereof is, for example, 1 or 2, and preferably 1.

Examples of ^R2 include cyclic or chain groups having 2 to 20 carbon atoms that can form an intramolecular hydrogen bond with a hydroxyl group, alkanediyloxycarbonyl groups having 2 to 20 carbon atoms, alkanediylcarbonyl groups having 2 to 20 carbon atoms, alkanediyl groups having 4 to 20 carbon atoms, alkanediyloxy groups having 2 to 20 carbon atoms, and alkanediylcarbonyloxy groups having 2 to 20 carbon atoms, and it is preferable that R2 contains at least one selected from the group consisting of these.

When Ar ¹ does not have a hydroxyl group capable of forming an intramolecular hydrogen bond or has a hydroxyl group at the ortho position of the azo group connecting Ar ¹ and Ar ² , R ² represents at least one group selected from the group consisting of an alkanediyl group having 4 to 20 carbon atoms, an alkanediyloxy group having 2 to 20 carbon atoms, an alkanediyloxycarbonyl group having 2 to 20 carbon atoms, an alkanediylcarbonyl group having 2 to 20 carbon atoms, and an alkanediylcarbonyloxy group having 2 to 20 carbon atoms.

Examples of alkanediyl groups having 4 to 20 carbon atoms include alkanediyl groups formed by removing one hydrogen atom from an unsubstituted (unsubstituted) linear or branched alkyl group having 4 to 20 carbon atoms, such as n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, or n-decyl. The alkanediyl group preferably has 4 to 16 carbon atoms, and more preferably 4 to 12 carbon atoms.

One or more hydrogen atoms constituting the alkyl group having 4 to 20 carbon atoms may be substituted with a halogen atom (e.g., a fluorine atom), a hydroxy group, an amino group, or a substituted amino group. Examples of substituted amino groups include amino groups substituted with one or two alkyl groups having 1 to 20 carbon atoms, such as N-methylamino, N-ethylamino, N,N-dimethylamino, and N,N-diethylamino. Examples of alkyl groups in which one or more hydrogen atoms are substituted with a halogen atom, hydroxy group, amino group, or the like include haloalkyl groups having 4 to 20 carbon atoms, such as fluorobutyl and octafluorobutyl; hydroxyalkyl groups having 4 to 20 carbon atoms, such as hydroxybutyl, hydroxypentyl, and hydroxyhexyl; and alkyl groups having 4 to 20 carbon atoms and an unsubstituted or substituted amino group, such as aminobutyl and 2-(N,N-dimethylamino)butyl.

Examples of alkanediyloxy groups having 2 to 20 carbon atoms include alkanediyloxy groups formed by removing one hydrogen atom from an unsubstituted, linear or branched alkoxy group having 2 to 20 carbon atoms, such as ethoxy, n-propoxy, isopropyloxy, n-butoxy, isobutyloxy, tert-butoxy, n-pentyloxy, isopentyloxy, neopentyloxy, n-hexyloxy, n-heptyloxy, n-octyloxy, n-nonyloxy, and n-decyloxy. The alkanediyloxy group preferably has 2 to 16 carbon atoms, and more preferably 2 to 12 carbon atoms.

One or more hydrogen atoms constituting the alkoxy group having 2 to 20 carbon atoms may be substituted with a halogen atom (e.g., a fluorine atom), a hydroxy group, an amino group, or a substituted amino group. Substituted amino groups are the same as those described above. Examples of alkoxy groups in which one or more hydrogen atoms are substituted with a halogen atom, hydroxy, amino group, or the like include haloalkoxy groups having 2 to 20 carbon atoms, such as tetrafluoroethoxy and octafluorobutoxy; hydroxyalkoxy groups having 2 to 20 carbon atoms, such as 2-hydroxyethoxy; and alkoxy groups having 2 to 20 carbon atoms and an unsubstituted or substituted amino group, such as aminoethoxy and 2-(N,N-dimethylamino)ethoxy.

Examples of alkanediyloxycarbonyl groups having 2 to 20 carbon atoms include alkanediyloxycarbonyl groups formed by removing one hydrogen atom from an unsubstituted alkoxycarbonyl group having 2 to 20 carbon atoms, such as a methoxycarbonyl group, ethoxycarbonyl group, n-propoxycarbonyl group, isopropoxycarbonyl group, n-butoxycarbonyl group, isobutoxycarbonyl group, tert-butoxycarbonyl group, n-pentyloxycarbonyl group, isopentyloxycarbonyl group, neopentyloxycarbonyl group, n-hexyloxycarbonyl group, n-heptyloxycarbonyl group, n-octyloxycarbonyl group, n-nonyloxycarbonyl group, or n-decyloxycarbonyl group. The alkanediyl moiety of the alkanediyloxycarbonyl group preferably has 1 to 16 carbon atoms, and more preferably 1 to 12 carbon atoms.

One or more hydrogen atoms constituting the alkoxycarbonyl group having 2 to 20 carbon atoms may be substituted with a halogen atom (e.g., a fluorine atom), a hydroxy group, an amino group, or a substituted amino group. Substituted amino groups are the same as those described above. Examples of alkoxycarbonyl groups in which one or more hydrogen atoms have been replaced with a halogen atom, hydroxy group, amino group, etc. include haloalkoxycarbonyl groups having 2 to 20 carbon atoms, such as a fluoroethoxycarbonyl group, trifluoroethoxycarbonyl group, tetrafluoroethoxycarbonyl group, and octafluorobutoxycarbonyl group.

Examples of alkanediylcarbonyl groups having 2 to 20 carbon atoms include alkanediylcarbonyl groups formed by removing one hydrogen atom from an unsubstituted alkanoyl group having 2 to 20 carbon atoms, such as an acetyl group, ethylcarbonyl group, n-propylcarbonyl group, isopropylcarbonyl group, n-butylcarbonyl group, isobutylcarbonyl group, tert-butylcarbonyl group, n-pentylcarbonyl group, isopentylcarbonyl group, neopentylcarbonyl group, n-hexylcarbonyl group, n-heptylcarbonyl group, n-octylcarbonyl group, n-nonylcarbonyl group, or n-decylcarbonyl group. The number of carbon atoms in the alkanediylcarbonyl group's alkanediyl moiety is preferably 1 to 16, and more preferably 1 to 12.

One or more hydrogen atoms constituting the alkanoyl group having 2 to 20 carbon atoms may be substituted with a halogen atom (e.g., a fluorine atom), a hydroxy group, an amino group, or a substituted amino group. Substituted amino groups are the same as those described above. Examples of alkanoyl groups in which one or more hydrogen atoms are substituted with a halogen atom, hydroxy group, or the like include haloacyl groups having 2 to 20 carbon atoms, such as a fluoroethoxycarbonyl group, a trifluoroethoxycarbonyl group, a tetrafluoroethylcarbonyl group, and an octafluorobutylcarbonyl group.

Examples of alkanediylcarbonyloxy groups having 2 to 20 carbon atoms include alkanediylcarbonyloxy groups formed by removing one hydrogen atom from an unsubstituted alkanoyloxy group having 2 to 20 carbon atoms, such as acetyloxy group, ethylcarbonyloxy group, n-propylcarbonyloxy group, isopropylcarbonyloxy group, n-butylcarbonyloxy group, isobutylcarbonyloxy group, tert-butylcarbonyloxy group, n-pentylcarbonyloxy group, isopentylcarbonyloxy group, neopentylcarbonyloxy group, n-hexylcarbonyloxy group, n-heptylcarbonyloxy group, n-octylcarbonyloxy group, n-nonylcarbonyloxy group, and n-decylcarbonyloxy group. The number of carbon atoms in the alkanediylcarbonyloxy group is preferably 1 to 16, and more preferably 1 to 12.

One or more hydrogen atoms constituting the alkanoyloxy group having 2 to 20 carbon atoms may be substituted with a halogen atom (e.g., a fluorine atom), a hydroxy group, an amino group, or a substituted amino group. Substituted amino groups are the same as those described above. Examples of alkanoyloxy groups in which one or more hydrogen atoms are substituted with a halogen atom, hydroxy group, or the like include haloacyloxy groups having 2 to 20 carbon atoms, such as a tetrafluoroethylcarbonyloxy group or an octafluorobutylcarbonyloxy group.

At least one of the -CH 2 - groups constituting the alkyl group moiety constituting the alkyl group having 4 to 20 carbon atoms, the alkoxy group having 2 to 20 carbon atoms, the alkoxycarbonyl group having 2 to 20 carbon atoms, the alkanoyl group having ₂ to 20 carbon atoms, or the alkanoyloxy group having 2 to 20 carbon atoms may be substituted with at least one of -O- and -NR ^* -. Here, R ^* represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, and examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a butyl group, and a hexyl group. Examples of the substituted alkyl group having -O- or -NR ^* - inserted between carbon atoms include a 2-ethoxyethyl group, a 2-(2-ethoxyethoxy)ethyl group, and a 2-[2-(ethylamino)ethyl)amino]ethyl group.

When ^Ar1 has a hydroxyl group capable of forming an intramolecular hydrogen bond at the ortho position of ^R2 , ^R2 represents a cyclic or chain-like group having 2 to 20 carbon atoms capable of forming an intramolecular hydrogen bond with the hydroxyl group. ^R2 may preferably be a chain-like group having 2 to 20 carbon atoms capable of forming an intramolecular hydrogen bond with the hydroxyl group. Examples of the cyclic group represented by ^R2 capable of forming an intramolecular hydrogen bond with the hydroxyl group include a 2-pyrrolidinediyl group, a 2-piperidinediyl group, a 2-pyrimidinediyl group, a 2-thiazolediyl group, a 2-thiazolinediyl group, a 2-oxazolediyl group, and a 2-oxazolinediyl group, and it is preferable that the cyclic group contains at least one selected from the group consisting of these. The cyclic group capable of forming an intramolecular hydrogen bond with the hydroxyl group may have a substituent. Examples of the substituent include a halogen atom (e.g., a fluorine atom), a hydroxyl group, an optionally substituted amino group, an alkoxy group, an alkyl group, and an alkylcarbonyl group. When the substituent has an alkyl moiety, it may have, for example, 1 to 10 carbon atoms.

Examples of the chain group represented by ^R2 and capable of forming an intramolecular hydrogen bond with a hydroxyl group include an alkanediyloxycarbonyl group having 2 to 20 carbon atoms and an alkanediylcarbonyl group having 2 to 20 carbon atoms, and it is preferable to include at least one selected from the group consisting of these. The alkanediyloxycarbonyl group having 2 to 20 carbon atoms and the alkanediylcarbonyl group having 2 to 20 carbon atoms are as described above.

^R3 represents a polymerizable group or a hydrogen atom. Examples of the polymerizable group represented by ^R3 include a (meth)acrylate group ((meth)acryloyloxy group), a vinylphenyl group, a vinyl group, and an epoxy group. The polymerizable group is preferably a radically polymerizable group, and particularly preferably a (meth)acrylate group.

n represents 1 or 2. When n is 2, two Ar ² 's may be the same or different.

The compound represented by formula (1) has at least one hydroxyl group capable of forming an intramolecular hydrogen bond in at least one of Ar ¹ , Ar ² and Ar ^3. The number of hydroxyl groups capable of forming an intramolecular hydrogen bond in the compound represented by formula (1) may be, for example, 1. Examples of intramolecular hydrogen bonds in the compound represented by formula (1) are shown below, but the present invention is not limited to these embodiments. In the following examples, Ar ¹ , Ar ² and Ar ³ are conveniently represented as 1,4-phenylene groups, but the present invention is not limited to this. Furthermore, R ²¹ represents an alkanediyl group having 2 to 20 carbon atoms.

(1) When Ar ¹ has a hydroxyl group capable of forming an intramolecular hydrogen bond The hydroxyl group on Ar ¹ can form a 6-membered cyclic intramolecular hydrogen bond with, for example, an azo group connecting Ar ¹ and Ar ² or with R ^2. Examples of a mode in which the hydroxyl group on Ar ¹ forms an intramolecular hydrogen bond with R ² include the following (a). Examples of a mode in which the hydroxyl group on Ar ¹ forms an intramolecular hydrogen bond with the azo group connecting Ar ¹ and Ar ² include the following (b).

(2) When ^Ar2 has a hydroxyl group capable of forming an intramolecular hydrogen bond The hydroxyl group on ^Ar2 can form a six-membered cyclic intramolecular hydrogen bond, for example, with the azo group linking ^Ar1 and ^Ar2 or the azo group linking ^Ar2 and ^Ar3 . Examples of embodiments in which the hydroxyl group on ^Ar2 forms an intramolecular hydrogen bond with ^the azo group linking Ar1 and ^Ar2 include the following (c). Examples of embodiments in which the hydroxyl group on ^Ar2 forms an intramolecular hydrogen bond with the azo group linking ^Ar2 and ^Ar3 include the following (d).

(3) When ^Ar3 has a hydroxyl group capable of forming an intramolecular hydrogen bond, the hydroxyl group on ^Ar3 can form, for example, a six-membered cyclic intramolecular hydrogen bond with the azo group connecting ^Ar2 and ^Ar3 . Specific examples include the following (e).

From the viewpoint of improving the dichroic ratio, the form of the intramolecular hydrogen bond is preferably any one of (a) to (e), more preferably any one of (a) to (d), and even more preferably any one of (a) and (c).

The presence or absence of an intramolecular hydrogen bond can be determined by measuring ¹ H-NMR. For example, as described in https://www.chem-station.com/yukitopics/nmr-analysis.htm and "Spectroscopic Identification of Organic Compounds (6th Edition)" (1999, Tokyo Kagaku Dojin, pp. 162-165), the protons of a hydroxyl group that forms a hydrogen bond are observed on the lower magnetic field side compared to when no hydrogen bond is formed. The chemical shift of a hydroxyl group that forms an intramolecular hydrogen bond may be, for example, 9.0 ppm or more and 18.0 ppm or less in deuterated chloroform (CDCl ₃ ), and may preferably be 10.0 ppm or more.

In addition, the chemical shift of a hydroxyl group is generally greatly affected by the polarity of the measurement solvent. Specifically, in a highly polar solvent (e.g., DMSO-d ₆ ), there is a large shift toward the low magnetic field. However, when the hydroxyl group forms a hydrogen bond, the influence of the measurement solvent is reduced. The difference between the chemical shift of a hydroxyl group forming an intramolecular hydrogen bond in a highly polar solvent (e.g., DMSO-d ₆ ) and in a low polar solvent (e.g., CDCl ₃ ) may be, for example, 1.0 ppm or less, or may be 0.5 ppm or less.

The maximum absorption wavelength (λmax) of the compound represented by formula (1) may be, for example, 350 nm or more and 650 nm or less, preferably 380 nm or more and 600 nm or less. The maximum absorption wavelength is measured at room temperature (e.g., 25°C) for a chloroform solution of the compound represented by formula (1). The maximum absorption wavelength of the compound represented by formula ( ¹ ) can be adjusted to a desired wavelength by appropriately selecting, for example, the skeletal structure of Ar1, ^Ar2 , and ^Ar3 , the substituents in ^Ar1 , ^Ar2 , ^and Ar3, n, ^R1, etc.

Specific examples of compounds represented by formula (1) include compounds represented by the following formulas (1-1) to (1-78), but the present invention is not limited to these.

From the viewpoint of improving the dichroic ratio, the compound represented by formula (1) is preferably at least one selected from the group consisting of compounds represented by any one of formulas (1-1) to (1-56), more preferably at least one selected from the group consisting of compounds represented by any one of formulas (1-1) to (1-46), even more preferably at least one selected from the group consisting of compounds represented by any one of formulas (1-1) to (1-31), and particularly preferably at least one selected from the group consisting of compounds represented by any one of formulas (1-1) to (1-20).

Method for Producing Compound Represented by Formula (1) The compound represented by formula (1) can be produced by appropriately applying a conventionally known synthesis method. Specifically, the azo structure (—N═N—) in the compound represented by formula (1) can be constructed by converting an aromatic amine compound having a primary amino group into a diazonium salt using sodium nitrite or the like, and then diazo-coupling it with an aromatic compound, for example, with reference to the description of the production example in paragraphs [0220] to [0268] of International Publication WO 2016/136561. Furthermore, an azo structure containing a thiazole structure can be constructed with reference to the description in, for example, J. Mol. Struct., 2011, 987,158.

A compound in which ^R3 is an alkanediyloxy group can be produced as a compound having the desired alkanediyloxy group by, for example, applying an SN2 substitution reaction to a precursor having a hydroxy group. The SN2 substitution reaction may be carried out under conventionally known reaction conditions, or the description in, for example, J. Am. Chem. Soc., 2008, 130, 13079 may be referred to.

When the compound represented by formula (1) contains -OC(=O)- or C(=O)O-, it can be synthesized, for example, by applying a dehydration condensation reaction using a precursor having a carboxy group and a precursor having a hydroxyl group, with reference to Jiang, L.; Lu, X.; Zhang, H.; Jiang, Y.; Ma, D. J. Org. Chem. 2009, 74 (3), 4542-4546. Specific examples include condensation conditions in a solvent in the presence of an esterification condensing agent.

Compounds having a hydroxyl group in Ar ¹ , Ar ² or Ar ³ can be converted to a hydroxyl group by demethylation with reference to literature on the demethylation reaction of salicylic acid type methoxy groups (for example, (Chem. Commun. 2010, 46, 9019-9021.). For example, conditions using a demethylating agent in a solvent can be used. The solvent can be an aprotic polar solvent, which can be a single solvent or a mixed solvent. Examples of the aprotic polar solvent include amide solvents, lactone solvents, nitrogen-containing aromatic solvents, sulfoxide solvents, etc. Examples of the amide solvent include N,N-dimethylacetamide, N-methyl-pyrrolidone, N-methylcaprolactam, N,N-dimethylformamide, N,N-diethylformamide, N,N-diethylacetamide, N-methylpropionamide, dimethylimidazolidinone, etc. Examples of the lactone solvent include γ-butyllactone and β-butyllactone. Examples of aromatic solvents include pyridine and quinoline. Examples of sulfoxide solvents include dimethyl sulfoxide and methylphenyl sulfoxide. Among these, preferred examples include amide solvents such as N-methyl-2-pyrrolidone, and nitrogen-containing aromatic solvents such as pyridine. Of these, a mixed solvent of N-methyl-2-pyrrolidone and pyridine is more preferred. As the demethylating agent, it is preferred to use a lithium salt, and lithium chloride is more preferred. The reaction temperature is, for example, in the range of 0°C to 200°C, preferably in the range of 20°C to 150°C, and more preferably in the range of 50°C to 120°C. After completion of the reaction, the mixture is cooled to room temperature, and a poor solvent such as hydrochloric acid or water is added dropwise to precipitate the demethylated product.

When producing a compound represented by formula (1), if a hydroxyl group in a synthetic intermediate inhibits the desired reaction, the hydroxyl group can be appropriately protected and the protecting group removed after the reaction to allow the desired reaction to occur. Common protecting groups such as acetyl and silyl groups can be used. Well-known reaction conditions for protection and deprotection can be used.

The reaction time in the method for producing the compound represented by formula (1) can also be determined by appropriately sampling the reaction mixture during the reaction and confirming the degree of disappearance of the raw material compounds and the degree of production of the compound represented by formula (1) using known analytical methods such as liquid chromatography and gas chromatography.

The compound represented by formula (1) can be isolated from the reaction mixture after the reaction by known methods such as recrystallization, reprecipitation, extraction, and various types of chromatography, or by an appropriate combination of these procedures.

The composition may further contain at least one other dye compound besides the compound represented by Formula (1), for example, a dichroic dye. Examples of the other dye compound include azo dyes such as monoazo dyes, bisazo dyes, trisazo dyes, tetrakisazo dyes, and stilbene azo dyes. At least one selected from these groups is preferred. The composition may contain one or more of the other dye compounds alone or in combination. For example, when used as a coating-type polarizing plate material, the other dye compound contained in the composition preferably has a maximum absorption wavelength in a wavelength range different from that of the compound represented by Formula (1). For example, when used as a coating-type polarizing plate material, the composition preferably contains a combination of three or more dichroic dyes, including the compound represented by Formula (1), and more preferably a combination of three or more azo dyes. By containing a combination of three or more dye compounds with different maximum absorption wavelengths in the composition, it is possible, for example, to obtain absorption across the entire visible light range by a film formed from the composition.

If the composition contains other coloring compounds, the content thereof is preferably 50 parts by mass or less, more preferably in the range of 0.1 to 10 parts by mass, and even more preferably in the range of 0.1 to 5 parts by mass, per 100 parts by mass of the solid content of the composition. Within the above range, the other coloring compounds can be sufficiently dispersed.

Liquid Crystalline Compound The composition contains a liquid crystal compound including at least one of a polymerizable liquid crystal compound and a liquid crystal polymer compound in addition to the compound represented by formula (1). The composition may contain only one of a polymerizable liquid crystal compound and a liquid crystal polymer compound, or may contain both. The composition may contain two or more types of each of a polymerizable liquid crystal compound and a liquid crystal polymer compound. By containing at least one of a polymerizable liquid crystal compound and a liquid crystal polymer compound, a composition can be formed in which the compound represented by formula (1) is dispersed in the liquid crystal compound.

The liquid crystalline polymer compound may be one that constitutes a thermotropic liquid crystalline polymer or one that constitutes a lyotropic liquid crystalline polymer. The liquid crystalline polymer compound is preferably one that constitutes a thermotropic liquid crystalline polymer, as this allows for precise control of the film thickness.

Liquid crystals are classified into smectic liquid crystals, nematic liquid crystals, and cholesteric liquid crystals depending on the molecular arrangement structure in the liquid crystal state. Of these, smectic liquid crystals are preferred for polarizing film applications. Therefore, the polymerizable liquid crystal compound is preferably a polymerizable smectic liquid crystal compound, and the liquid crystalline polymer compound is preferably a smectic liquid crystalline polymer compound.

By using polymerizable liquid crystal compounds exhibiting smectic liquid crystallinity and polymer compounds exhibiting smectic liquid crystallinity, polarizing films with high orientational order can be formed. The liquid crystal state exhibited by the polymerizable liquid crystal compounds and liquid crystalline polymer compounds is preferably a smectic phase (smectic liquid crystal state), and from the viewpoint of achieving a higher degree of orientational order, a high-order smectic phase (high-order smectic liquid crystal state) is more preferable. Here, high-order smectic phase refers to smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic I phase, smectic J phase, smectic K phase, and smectic L phase. Of these, smectic B phase, smectic F phase, and smectic I phase are more preferred. Polarizing films with high orientational order exhibit Bragg peaks derived from higher-order structures such as hexatic and crystalline phases in X-ray diffraction measurements. The Bragg peak refers to a peak derived from the planar periodic structure of molecular orientation. The periodic spacing (order period) of a polarizing film obtained from the composition is preferably 0.3 nm or more and 0.6 nm or less. The polymerizable liquid crystal compound or liquid crystalline polymer compound may be a polymerizable smectic liquid crystal compound or a smectic liquid crystalline polymer compound that exhibits a Bragg peak derived from a higher-order structure in X-ray diffraction measurement.

Polymerizable Liquid Crystal Compound A polymerizable liquid crystal compound is a compound that has at least one polymerizable group in the molecule and can exhibit a liquid crystal phase by orienting. The polymerizable liquid crystal compound is preferably a compound that can exhibit a liquid crystal phase by orienting alone. The polymerizable group refers to a functional group that can participate in a polymerization reaction, and is preferably a radically polymerizable group.

The polymerizable liquid crystal compound is not particularly limited as long as it has at least one polymerizable group and preferably exhibits smectic liquid crystal properties, and known polymerizable liquid crystal compounds can be used. Specific examples of preferred polymerizable liquid crystal compounds include compounds represented by the following formula (A) (hereinafter also referred to as "polymerizable liquid crystal compound (A)"):

In formula (A), k is an integer of 1 to 3. ^{X 1} , X ² , and X ³ each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group. When k is 2 or 3, multiple X 1s may be the same or different. At least three selected from the group consisting of X ¹ , X ² , and X ³ represent a divalent 6-membered hydrocarbon ring group. ^{Y 1} , Y ² , W ¹ , and W ² each independently represent a single bond or a divalent linking group. When k is 2 or 3, Y ^1s may be the same or different. ^{V 1} and V ² each independently represent an alkanediyl group having 1 to 20 carbon atoms which may have a substituent. At least one of the -CH ₂ -s constituting the alkanediyl group may be substituted with -O-, -CO-, -S-, or -NH-. U ¹ and U ² each independently represent a polymerizable group or a hydrogen atom, and at least one of them represents a polymerizable group.

Examples of the divalent aromatic groups represented by X ¹ , X ² , and X ³ include a 1,4-phenylene group and a 1,4-naphthylene group (naphthalene-1,4-diyl group). Examples of the divalent alicyclic hydrocarbon groups include a cyclohexane-1,4-diyl group. At least one of the divalent aromatic groups and divalent alicyclic hydrocarbon groups represented by X ¹ , X ² , and X ³ may have a substituent. Examples of the substituent include an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, or an n-butyl group, a cyano group, or a halogen atom. At least one of the -CH ₂ - groups constituting the divalent alicyclic hydrocarbon group may be substituted with -O-, -S-, or -NR-. Here, R represents an alkyl group having 1 to 6 carbon atoms or a phenyl group.

Examples of the divalent 6-membered hydrocarbon ring group for X ¹ , X ² and X ³ include an optionally substituted 1,4-phenylene group and an optionally substituted cyclohexane-1,4-diyl group.

The divalent aromatic group for X ¹ , X ² and X ³ is preferably a 1,4-phenylene group which may have a substituent, more preferably an unsubstituted 1,4-phenylene group. The divalent alicyclic hydrocarbon group is preferably a cyclohexane-1,4-diyl group which may have a substituent, more preferably a trans-cyclohexane-1,4-diyl group which may have a substituent, and even more preferably an unsubstituted trans-cyclohexane-1,4-diyl group.

^Y1 and ^Y2 each independently represent a single bond or a divalent linking group. The divalent linking group is, for example, at least one selected from the group consisting _{of -CH2CH2-} , _-CH2O- , -(C=O)O-, -O(C=O)O-, -N=N-, ^-CRa = ^CRb- , -C≡C-, and ^-CRa =N-. Here, ^Ra and ^Rb each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ^Y1 is preferably _-CH2CH2- , _{- (} C=O)O-, or a single bond. ^Y2 is preferably _-CH2CH2- or _-CH2O- .

^W1 and ^W2 each independently represent a single bond or a divalent linking group. The divalent linking group is, for example, at least one selected from the group consisting of -O-, -S-, -(C=O)O-, and -O(C=O)O-. ^W1 and ^W2 each independently represent, preferably, a single bond or -O-.

^V1 and ^V2 each independently represent an alkanediyl group having 1 to 20 carbon atoms which may have a substituent, in which at least one of _-CH2- constituting the alkanediyl group may be replaced by -O-, -CO-, -S- or -NH-.

Examples of the alkanediyl group represented by ^V1 and ^V2 include a methylene group, 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, an octane-1,8-diyl group, a decane-1,10-diyl group, a tetradecane-1,1-diyl group, and an icosane-1,20-diyl group. ^V1 and ^V2 are preferably alkanediyl groups having 2 to 12 carbon atoms, and more preferably alkanediyl groups having 6 to 12 carbon atoms.

Optional substituents on the optionally substituted alkanediyl group having 1 to 20 carbon atoms include a cyano group and a halogen atom. The alkanediyl group is preferably an unsubstituted alkanediyl group, and more preferably an unsubstituted, linear alkanediyl group.

^U1 and ^U2 each independently represent a polymerizable group or a hydrogen atom, and at least one represents a polymerizable group. ^U1 and ^U2 are preferably polymerizable groups. It is preferable that both ^U1 and ^U2 are polymerizable groups, and it is preferable that both are radically polymerizable groups. The polymerizable group represented by ^U1 and the polymerizable group represented by ^U2 may be different from each other, but it is preferable that they are the same type of group. Examples of the polymerizable group in ^U1 and ^U2 include the same polymerizable groups as those exemplified above as the polymerizable group possessed by the polymerizable liquid crystal compound. Among them, the polymerizable group represented by ^U1 and ^U2 is preferably at least one selected from the group consisting of a vinyloxy group, an acryloyloxy group, a methacryloyloxy group, an oxiranyl group, and an oxetanyl group, and an acryloyloxy group is more preferable.

Specific examples of the polymerizable liquid crystal compound (A) include compounds represented by the following formulas (A-1) to (A-17). When the polymerizable liquid crystal compound (A) has a cyclohexane-1,4-diyl group, the cyclohexane-1,4-diyl group is preferably a trans type.

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

The polymerizable liquid crystal compound (A) can be produced by methods described in known publications, such as Lub et al. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996) and Japanese Patent No. 4719156.

Liquid crystalline polymer compound The liquid crystalline polymer compound may be a compound obtained by polymerizing the polymerizable liquid crystal compound (hereinafter also referred to as a polymer of the polymerizable liquid crystal compound), or may be any other liquid crystalline polymer compound, and is preferably a polymer of the polymerizable liquid crystal compound.

The polymer of the polymerizable liquid crystal compound may use two or more of the polymerizable liquid crystal compounds as raw material monomers. Furthermore, the polymer of the polymerizable liquid crystal compound may contain a monomer other than the polymerizable liquid crystal compound as a raw material monomer.

The content of the polymerizable liquid crystal compound in the polymer of the polymerizable liquid crystal compound is typically 1 mol % or more and 100 mol % or less relative to the total amount of structural units derived from the polymerizable liquid crystal compound that constitute the polymer of the polymerizable liquid crystal compound. From the viewpoint of increasing the orientation of the polymer of the polymerizable liquid crystal compound, the content is preferably 30 mol % or more and 100 mol % or less, more preferably 50 mol % or more and 100 mol %, and even more preferably 80 mol % or more and 100 mol % or less.

The other liquid crystalline polymer compounds include polymer compounds having liquid crystalline groups. For example, polymer compounds that serve as the backbone include polyolefins such as polyethylene and polypropylene; cyclic olefin resins such as norbornene polymers; polyalkylene ethers; polyvinyl alcohols; polymethacrylates; polyacrylic esters; and the like. These polymer compounds have liquid crystalline groups. Among these, polymethacrylates and polyacrylic esters having liquid crystalline groups are preferred.

The other liquid crystalline polymer compounds may contain two or more types of liquid crystalline groups. The liquid crystalline groups may be contained in the main chain of the polymer compound that forms the parent skeleton, in the side chain of the polymer compound that forms the parent skeleton, or in both the main chain and the side chain of the polymer compound that forms the parent skeleton. Examples of liquid crystalline groups include groups formed by removing one hydrogen atom from a compound having at least two six-membered hydrocarbon ring structures, or groups formed by removing two hydrogen atoms from such a compound.

The content of liquid crystalline groups in the other liquid crystalline polymer compounds is typically 1 mol% or more and 100 mol% or less relative to the total amount of structural units constituting the polymer compound that forms the backbone of the other liquid crystalline polymer compounds. From the viewpoint of increasing the alignment of the other liquid crystalline polymer compounds, the content is preferably 30 mol% or more and 100 mol% or less, more preferably 50 mol% or more and 100 mol% or less, and even more preferably 80 mol% or more and 100 mol% or less.

When two or more types of polymerizable liquid crystal compounds are combined in a composition, it is preferable that at least one of them is polymerizable liquid crystal compound (A), and more preferably two or more of them are polymerizable liquid crystal compound (A). By combining two or more types of polymerizable liquid crystal compounds, it may be possible to temporarily maintain a liquid crystal phase even at temperatures below the liquid crystal-crystalline phase transition temperature. The total content of polymerizable liquid crystal compound (A) in the composition is preferably 40% by mass or more, more preferably 60% by mass or more, based on the total mass of all polymerizable liquid crystal compounds in the composition. All of the polymerizable liquid crystal compounds may be polymerizable liquid crystal compound (A). When the content of polymerizable liquid crystal compound (A) is within the above range, the polymerizable liquid crystal compounds are likely to align with a high degree of orientational order, and the compound represented by formula (1) is oriented in accordance with this order, resulting in a polarizing film with excellent polarization performance.

From the viewpoint of increasing the alignment of the polymerizable liquid crystal compound and the liquid crystalline polymer compound, the total content of the polymerizable liquid crystal compound and the liquid crystalline polymer compound in the composition is, for example, 50 parts by mass or more, preferably 70 parts by mass or more and 99.9 parts by mass or less, more preferably 70 parts by mass or more and 99.5 parts by mass or less, even more preferably 80 parts by mass or more and 99 parts by mass or less, particularly preferably 80 parts by mass or more and 94 parts by mass or less, and even more preferably 80 parts by mass or more and 90 parts by mass or less, per 100 parts by mass of the solid content of the composition.

The total content of the compounds represented by formula (1) in the composition is typically 0.1 to 50 parts by mass, preferably 0.1 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable liquid crystal compound and the liquid crystalline polymer compound. When the total content of the compounds represented by formula (1) relative to the total amount of the polymerizable liquid crystal compound and the liquid crystalline polymer compound is 50 parts by mass or less, there tends to be less disorder in the orientation of the polymerizable liquid crystal compound, the liquid crystalline polymer compound, and the compound represented by formula (1), and a polarizing film with a high degree of orientational order tends to be obtained.

Polymer Compound The composition may further contain a polymer compound in addition to the compound represented by Formula (1) and the polymerized liquid crystal compound. When the composition contains a polymer compound, the compound represented by Formula (1) may be more easily dispersed in the composition. The polymer compound that may be contained in the composition is not particularly limited as long as it can disperse the compound represented by Formula (1). Acrylic polymers such as polymethyl methacrylate (PMMA) are preferred because they facilitate uniform dispersion of the compound represented by Formula (1). The polymer compound may also be a polymer compound obtained by polymerizing the polymerizable liquid crystal compound described above. The weight-average molecular weight of the polymer compound, in terms of polystyrene, is, for example, 10,000 to 200,000, preferably 20,000 to 150,000.

When the composition contains a polymer compound, its content can be selected appropriately depending on the purpose, etc. The content of the polymer compound is preferably 10 parts by mass or less, more preferably 5.0 parts by mass or less, and even more preferably 3.0 parts by mass or less, per 100 parts by mass of the solid content of the composition.

The composition preferably further contains a liquid medium such as a solvent and a polymerization initiator, and may further contain a photosensitizer, polymerization inhibitor, leveling agent, etc. as needed.

The solvent is preferably a solvent that can completely dissolve the compound represented by formula (1), the polymerizable liquid crystal compound, the liquid crystalline polymer compound, and the polymer compound, and is preferably a solvent that is inactive to the polymerization reaction of the polymerizable liquid crystal compound.

Solvents include alcohol solvents, ester solvents, ketone solvents, aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, nitrile solvents, ether solvents, and chlorine-containing solvents. These solvents may be used alone or in combination of two or more.

When the composition contains a solvent, the solvent content is preferably 50% by mass or more and 98% by mass or less, based on the total amount of the composition. In other words, the solids content of the composition is preferably 2% by mass or more and 50% by mass or less. If the solids content is 50% by mass or less, the viscosity of the composition will be low, and the film obtained from the composition, for example, the film thickness, will tend to be generally uniform and less prone to unevenness. The solids content can be determined taking into account the thickness of the film to be produced.

Polymerization initiator The polymerization initiator is a compound capable of initiating the polymerization reaction of the polymerizable liquid crystal compound. The polymerization initiator is preferably a photopolymerization initiator, since it can initiate the polymerization reaction under lower temperature conditions. Specifically, photopolymerization initiators capable of generating active radicals or acids under the action of light are exemplified, and among these, photopolymerization initiators that generate radicals under the action of light are preferred.

Polymerization initiators include benzoin compounds, benzophenone compounds, alkylphenone compounds, acylphosphine oxide compounds, triazine compounds, iodonium salts, and sulfonium salts. The polymerization initiator can be appropriately selected from known polymerization initiators depending on the purpose. Furthermore, polymerization initiators can be used alone or in combination of two or more.

When the composition contains a polymerization initiator, its content may be determined appropriately depending on the type and amount of the polymerizable liquid crystal compound contained in the composition. The content of the polymerization initiator is, for example, 0.001 parts by mass or more, 0.01 parts by mass or more, 0.1 parts by mass or more, or 0.5 parts by mass or more, and, for example, 30% by mass or less, 10% by mass or less, or 8% by mass or less, relative to 100 parts by mass of the polymerizable liquid crystal compound. The content of the polymerization initiator is preferably 0.001 parts by mass or more and 30 parts by mass or less, more preferably 0.01 parts by mass or more and 10 parts by mass or less, and even more preferably 0.1 parts by mass or more and 8 parts by mass or less, relative to 100 parts by mass of the polymerizable liquid crystal compound. When the content of the polymerization initiator is within the above range, polymerization can be achieved without disturbing the alignment of the polymerizable liquid crystal compound.

Photosensitizer When the composition contains a photopolymerization initiator, the composition may preferably contain at least one photosensitizer. When the composition contains a photopolymerization initiator and a photosensitizer, the polymerization reaction of the polymerizable liquid crystal compound tends to be further accelerated. Examples of the photosensitizer include xanthone compounds such as xanthone and thioxanthone; anthracene compounds such as anthracene and alkoxy-substituted anthracene; phenothiazine and rubrene; and the like. The photosensitizer can be used alone or in combination of two or more.

When the composition contains a photosensitizer, the content of the photosensitizer in the composition may be determined appropriately depending on the type and amount of the photopolymerization initiator and polymerizable liquid crystal compound. The content of the photosensitizer in the composition is preferably 0.1 parts by mass or more and 30 parts by mass or less, more preferably 0.5 parts by mass or more and 10 parts by mass or less, and even more preferably 0.5 parts by mass or more and 8 parts by mass or less, per 100 parts by mass of the polymerizable liquid crystal compound.

Polymerization Inhibitor The composition may contain at least one polymerization inhibitor. Examples of polymerization inhibitors include hydroquinone, alkoxy group-containing hydroquinone, alkoxy group-containing catechol (e.g., butylcatechol), pyrogallol, radical scavengers such as 2,2,6,6-tetramethyl-1-piperidinyloxy radical, thiophenols, β-naphthylamines, and β-naphthols. By including a polymerization inhibitor in the composition, the degree of progress of the polymerization reaction of the polymerizable liquid crystal compound can be controlled.

When the composition contains a polymerization inhibitor, the content of the polymerization inhibitor in the composition is preferably 0.1 parts by mass or more and 30 parts by mass or less, more preferably 0.5 parts by mass or more and 10 parts by mass or less, and even more preferably 0.5 parts by mass or more and 8 parts by mass or less, relative to 100 parts by mass of the polymerizable liquid crystal compound.

Leveling Agent The composition may contain at least one leveling agent. The leveling agent has the function of adjusting the fluidity of the composition and making the coating film obtained by applying the composition flatter, and specific examples thereof include surfactants. The leveling agent is preferably at least one selected from the group consisting of leveling agents containing a polyacrylate compound as a main component and leveling agents containing a fluorine atom-containing compound as a main component. The leveling agents can be used alone or in combination of two or more.

When the composition contains a leveling agent, the content of the leveling agent is preferably 0.05 to 5 parts by mass, and more preferably 0.05 to 3 parts by mass, per 100 parts by mass of the total amount of the polymerizable liquid crystal compound and the liquid crystalline polymer compound. When the content of the leveling agent is within this range, the polymerizable liquid crystal compound and the liquid crystalline polymer compound are more easily horizontally aligned, unevenness is less likely to occur, and a smoother film, such as a polarizing film, tends to be obtained.

When the content of the leveling agent is within the above range, it is easy to horizontally align the polymerizable liquid crystal compound and the liquid crystalline polymer compound, and the resulting film tends to be smoother. If the content of the leveling agent relative to the polymerizable liquid crystal compound and the liquid crystalline polymer compound exceeds the above range, the resulting film tends to be more prone to unevenness.

Antioxidant The composition may contain an antioxidant. The antioxidant is not particularly limited as long as the composition can exhibit the effects of the present invention, and known antioxidants can be used. From the viewpoint of having a high inhibitory effect against light degradation of the compound represented by formula (1), the antioxidant is preferably a so-called primary antioxidant that has the effect of capturing radicals and preventing autoxidation. Therefore, it is more preferable that the antioxidant contained in the composition is at least one selected from the group consisting of phenolic compounds, alicyclic alcohol compounds, and amine compounds. The antioxidant may be used alone or in combination of two or more types.

The content of the antioxidant in the composition is preferably 0.1 parts by mass or more and 15 parts by mass or less, more preferably 0.3 parts by mass or more, even more preferably 0.5 parts by mass or more, more preferably 12 parts by mass or less, and even more preferably 10 parts by mass or less, per 100 parts by mass of the composition. When the content of the antioxidant is at least the above lower limit, photodegradation of the compound represented by formula (1) can be more effectively suppressed. On the other hand, when the content of the antioxidant is at most the above upper limit, the alignment of the polymerizable liquid crystal compound is less likely to be disturbed, and a greater effect of suppressing photodegradation of the compound represented by formula (1) can be expected.

The composition may contain additives other than those mentioned above. Examples of other additives include release agents, stabilizers, colorants such as bluing agents, flame retardants, and lubricants. If the composition contains other additives, the content of the other additives is preferably more than 0% and not more than 20% by mass, and more preferably more than 0% and not more than 10% by mass, based on the solids content of the composition.

The composition can be produced by a conventional method for preparing compositions. For example, it can be prepared by mixing and stirring the compound represented by formula (1), a liquid crystalline compound, and, if necessary, additives such as an antioxidant and a leveling agent.

<Compound>
The compound according to this embodiment is represented by the following formula (1a).

In formula (1a), k represents an integer of 1 or 2. When k is 2, two Ar ¹² may be the same or different.

Ar ¹¹ , Ar ¹² , and Ar ¹³ each independently represent a 1,4-phenylene group or a sulfur-containing heterocyclic group which may have a substituent. At least one of ^{Ar 11} and Ar ¹² has at least one hydroxyl group capable of forming an intramolecular hydrogen bond. Details of Ar ¹¹ , Ar ¹² , and Ar ¹³ are the same as those of Ar ¹ , Ar ² , and Ar ³ in formula (1), respectively, and preferred embodiments are also the same.

R ¹¹ represents an alkylamino group which may have a polymerizable group. Details of R ¹¹ are the same as those of R ¹ in formula (1), and preferred embodiments are also the same.

Examples of ^R12 include a cyclic or chain-like group having 2 to 20 carbon atoms that can form an intramolecular hydrogen bond with a hydroxyl group, an alkanediyloxycarbonyl group having 2 to 20 carbon atoms, an alkanediylcarbonyl group having 2 to 20 carbon atoms, an alkanediyl group having 4 to 20 carbon atoms, an alkanediyloxy group having 2 to 20 carbon atoms, etc., and it is preferable that R12 contains at least one selected from the group consisting of these. The details of ^R12 are the same as those of ^R2 in formula (1), and preferred embodiments are also the same.

R ¹³ represents a polymerizable group or a hydrogen atom. Details of R ¹³ are the same as those of R ³ in formula (1), and preferred embodiments are also the same.

<Membrane>
The film according to this embodiment may be a film containing a compound represented by formula (1) as a forming material, or may be a film obtained by using a composition containing a compound represented by formula (1) and a liquid crystalline compound as a forming material. A film made of the composition may be formed by applying the composition to a substrate and forming a film. Furthermore, when the composition contains a polymerizable liquid crystal compound, a film containing a cured product obtained by polymerizing the polymerizable liquid crystal compound may be formed by applying the composition to a substrate, forming a film, and then polymerizing and curing the polymerizable liquid crystal compound.

The composition can form a film with a high dichroic ratio, such as a polarizing film. Therefore, the film according to this embodiment is a polarizing film formed from a composition containing a compound represented by formula (1) and a liquid crystalline compound, and includes a polarizing film with a high dichroic ratio. The composition can also form a film with a high degree of orientational order, such as a polarizing film. Therefore, the film according to this embodiment is a polarizing film formed from a composition containing a compound represented by formula (1) and a liquid crystalline compound, and includes a polarizing film with a high degree of orientational order.

Here, a polarizing film with a high degree of orientational order exhibits Bragg peaks derived from higher-order structures such as hexatic and crystalline phases in X-ray diffraction measurement. Therefore, in a polarizing film formed from the composition, the polymerizable liquid crystal compound or liquid crystalline polymer compound is preferably oriented so as to exhibit a Bragg peak in X-ray diffraction measurement, and more preferably has a "horizontal orientation" in which the molecules of the polymerizable liquid crystal compound or liquid crystalline polymer compound are oriented in the direction in which light is absorbed. A high degree of orientational order that exhibits a Bragg peak can be achieved by controlling the type of polymerizable liquid crystal compound or liquid crystalline polymer compound used, the amount of the compound represented by formula (1), etc.

The compound represented by formula (1) and the liquid crystal compound that constitute the composition used to form the film are as described above.

The membrane can be produced, for example, by a method including the following steps.
Step A: forming a coating film of a composition containing a compound represented by formula (1), a liquid crystal compound, and a solvent;
Step B: Removing at least a portion of the solvent from the coating;
Step C: raising the temperature to a temperature at which the liquid crystalline compound undergoes a phase transition to a liquid phase or higher, and then lowering the temperature to cause the liquid crystalline compound to undergo a phase transition to a smectic phase (smectic liquid crystal state); and Step D: polymerizing the polymerizable liquid crystalline compound, if necessary, while maintaining the smectic phase (smectic liquid crystal state).

A coating film of the composition can be formed, for example, by applying the composition onto a substrate, an alignment film (described below), or the like. The composition may also be applied directly onto a retardation film or other layer that constitutes a polarizing plate.

The substrate is usually a transparent substrate. However, when the substrate is not placed on the display surface of a display element, for example, when the laminate from which the substrate has been removed is placed on the display surface of a display element, the substrate does not have to be transparent. A transparent substrate refers to a substrate that is transparent enough to transmit light, particularly visible light, and transparency refers to the property of having a transmittance of 80% or more for light in the wavelength range of 380 nm to 780 nm. Specific examples of transparent substrates include translucent resin substrates.

Resins that can be used to form the translucent resin substrate include polyolefins, cyclic olefin resins, polyvinyl alcohol, polyethylene terephthalate, polymethacrylates, polyacrylic esters, cellulose esters, polyethylene naphthalate, polycarbonates, polysulfones, polyethersulfones, polyetherketones, polyphenylene sulfide, and polyphenylene oxide. From the standpoints of availability and transparency, polyethylene terephthalate, polymethacrylates, cellulose esters, cyclic olefin resins, and polycarbonates are preferred.

The properties required of the substrate vary depending on the film configuration, but typically, a substrate with as little retardation as possible is preferred. Examples of substrates with as little retardation as possible include cellulose ester films with no retardation, such as Zerotack (Konica Minolta Opto, Inc.) and Ztack (Fujifilm Corporation). Unstretched cyclic olefin resin substrates are also preferred. Surfaces of the substrate not laminated with a film may be subjected to hard coating, anti-reflection treatment, anti-static treatment, etc.

The thickness of the substrate is typically 5 μm or more and 300 μm or less, preferably 20 μm or more and 200 μm or less, and more preferably 20 μm or more and 100 μm or less. If the thickness is above the lower limit, the decrease in strength is suppressed and processability tends to be improved.

Methods for applying the composition to a substrate or the like include known methods such as spin coating, extrusion, gravure coating, die coating, bar coating, and applicator coating, and printing methods such as flexography.

Next, at least a portion of the solvent contained in the coating film obtained from the composition is removed by drying or the like to form a dried coating film. Furthermore, if the coating film contains a polymerizable liquid crystal compound, the dried coating film is formed by drying under conditions that do not polymerize the polymerizable liquid crystal compound. Methods for drying the coating film include natural drying, forced air drying, heat drying, and reduced pressure drying.

Furthermore, to cause the liquid crystalline compound to undergo a phase transition to a liquid phase, the temperature is raised to a temperature at which the liquid crystalline compound undergoes a phase transition to a liquid phase or higher, and then the temperature is lowered to cause the liquid crystalline compound to undergo a phase transition to a smectic phase (smectic liquid crystal state). This phase transition may be carried out after the solvent in the coating film has been removed, or may be carried out simultaneously with the removal of the solvent.

When the composition contains a polymerizable liquid crystal compound, a film containing a cured product of the polymerizable liquid crystal compound is formed by polymerizing the polymerizable liquid crystal compound while maintaining its smectic liquid crystal state. Photopolymerization is the preferred polymerization method. The light irradiated onto the dried coating film during photopolymerization is appropriately selected depending on the type of photopolymerization initiator contained in the dried coating film, the type of polymerizable liquid crystal compound (particularly the type and amount of polymerizable groups possessed by the polymerizable liquid crystal compound), and the amount of light. Specific examples include visible light, ultraviolet light, infrared light, X-rays, alpha rays, beta rays, and gamma rays, and actinic electron beams. Among these, ultraviolet light is preferred because it allows for easy control of the polymerization reaction and allows the use of photopolymerization equipment widely used in the field. It is also preferable to select the type of polymerizable liquid crystal compound and photopolymerization initiator contained in the composition so that they can be photopolymerized by ultraviolet light. Furthermore, the polymerization temperature can be controlled by irradiating the dried coating film with light while cooling it with an appropriate cooling means. By using such cooling means, polymerization of the polymerizable liquid crystal compound can be carried out at a lower temperature, allowing for the formation of a suitable film even when a substrate with relatively low heat resistance is used. During photopolymerization, patterned films can also be obtained by performing masking and development.

Examples of light sources for the actinic energy rays include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, halogen lamps, carbon arc lamps, tungsten lamps, gallium lamps, excimer lasers, LED light sources emitting light in the wavelength range of 380 nm to 440 nm, chemical lamps, black light lamps, microwave-excited mercury lamps, and metal halide lamps.

The ultraviolet irradiation intensity may typically be 10 mW/ ^cm2 or more and 3,000 mW/ ^cm2 or less. The ultraviolet irradiation intensity is preferably an intensity in a wavelength region effective for activating the photopolymerization initiator. The light irradiation time may typically be 0.1 seconds or more and 10 minutes or less, preferably 0.1 seconds or more and 5 minutes or less, more preferably 0.1 seconds or more and 3 minutes or less, and even more preferably 0.1 seconds or more and 1 minute or less. When irradiating once or multiple times at such ultraviolet irradiation intensity, the cumulative light amount is preferably 10 mJ/ ^cm2 or more and 3,000 mJ/ ^cm2 or less.

By photopolymerizing the polymerizable liquid crystal compound, the compound polymerizes while maintaining the liquid crystal state of a smectic phase, preferably a highly smectic phase, to form a film. The film obtained by polymerizing the compound while maintaining the liquid crystal state of a smectic phase has the advantage of superior polarization performance, due in part to the action of the dichroic dye, compared to conventional host-guest polarizing films, i.e., films consisting of a nematic liquid crystal state. Furthermore, it has the advantage of superior strength compared to films coated with only a dichroic dye or lyotropic liquid crystal.

The thickness of the film can be selected appropriately depending on the display device to which it is applied, and is preferably 0.5 μm or more and 10 μm or less, more preferably 1 μm or more and 5 μm or less, and even more preferably 1 μm or more and 3 μm or less.

When the film is used as a polarizing film, it is preferably formed on an alignment film. The alignment film has the alignment control power to align the polymerizable liquid crystal compound and liquid crystalline polymer compound in the desired direction. The alignment film preferably has solvent resistance so that it does not dissolve when applied with a composition containing a liquid crystalline compound containing at least one of a polymerizable liquid crystal compound and a liquid crystalline polymer compound, and also has heat resistance during heat treatment to remove the solvent and align the polymerizable liquid crystal compound. Examples of such alignment films include alignment films containing an orienting polymer, photo-alignment films, and groove alignment films with a concave-convex pattern or multiple grooves on the surface. Photo-alignment films are preferred from the standpoint of alignment angle precision and quality.

<Laminate>
The laminate according to this embodiment may include a film containing a compound represented by formula (1) as a forming material, or may include a film formed from a composition containing a compound represented by formula (1) and a liquid crystalline compound. The laminate may include a substrate and a film containing a compound represented by formula (1) as a forming material disposed on the substrate, or may include a substrate, an alignment film disposed on the substrate, and a film containing a compound represented by formula (1) as a forming material disposed on the alignment film. The film containing a compound represented by formula (1) as a forming material may constitute a polarizing film. The substrate may also be a retardation film. The laminate can constitute, for example, a polarizing plate. The laminate can be produced, for example, by forming a film on a substrate according to the above-described film production method.

From the viewpoint of the flexibility and visibility of the display device, the thickness of the laminate is preferably 10 μm or more and 300 μm or less, more preferably 20 μm or more and 200 μm or less, and even more preferably 25 μm or more and 100 μm or less.

When the laminate has a retardation film as the substrate, the thickness of the retardation film can be selected appropriately depending on the display device to which it is applied.

<Display device>
The display device of this embodiment includes the laminate, and the laminate may be a polarizing plate. The display device can be obtained, for example, by bonding the laminate as a polarizing plate to the surface of the display device via an adhesive layer. A display device is a device having a display element, and includes a light-emitting element or a light-emitting device as a light source. Examples of display devices include liquid crystal display devices, organic electroluminescence (EL) display devices, inorganic electroluminescence (EL) display devices, electron emission display devices (e.g., field emission display devices (FEDs) and surface field emission display devices (SEDs)), electronic paper (display devices using electronic ink, electrophoretic elements, etc.), plasma display devices, projection display devices (e.g., grating light valve (GLV) display devices, display devices having digital micromirror devices (DMDs)), and piezoelectric ceramic displays. Liquid crystal display devices include transmissive liquid crystal display devices, semi-transmissive liquid crystal display devices, reflective liquid crystal display devices, direct-view liquid crystal display devices, and projection liquid crystal display devices. These display devices may display two-dimensional images or stereoscopic display devices displaying three-dimensional images. In particular, as the display device, an organic EL display device and a touch panel display device are preferable, and an organic EL display device is particularly preferable.

The present invention will be explained in more detail below using examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" and "%" are by weight. Also, "room temperature" and "RT" refer to 23°C.

Example 1: Synthesis of compound 1-1 To synthesize compound 1-1, first compounds 1-1-a, 1-1-b, and 1-1-c were synthesized, followed by deacetylation to obtain compound 1-1.

Synthesis of Compound 1-1-a
Ethyl 4-aminobenzoate (1.65 g, 10.0 mmol), 35% hydrochloric acid (2.65 mL, 30.0 mmol), and water (25.0 mL) were mixed and cooled to 0 to 5°C, and a solution of sodium nitrite (0.724 g, 1.05 mmol) in water (1.3 mL) was added dropwise. The mixture was then stirred for 1 hour while maintaining the temperature at 0 to 5°C, and a solution of amidosulfuric acid (49.0 mg, 0.505 mmol) in water (0.3 mL) was added to prepare a diazo solution. Meanwhile, 3-aminophenol (2.183 g, 20.0 mmol), sodium acetate (4.14 g, 50.5 mmol), and water (75.0 mL) were mixed and cooled to 0 to 5°C, and the entire amount of the diazo solution prepared earlier was added dropwise. After the dropwise addition, the mixture was heated to room temperature and stirred for 1 hour. The precipitated solid was filtered off to obtain Compound 1-1-a (2.28 g, yield 80%).

Synthesis of Compound 1-1-b Compound 1-1-a (0.856 g, 3.00 mmol), DMAP (N,N-dimethylaminopyridine, 38.0 mg, 0.301 mmol), triethylamine (0.365 g, 3.61 mmol), and chloroform (60.0 mL) were mixed and cooled to 0 to 5°C, and acetic anhydride (0.368 g, 3.60 mmol) was added dropwise. The reaction solution was then warmed to room temperature and stirred for 21 hours. Water was added to the reaction solution to separate the layers, and the organic layer was dried over magnesium sulfate and concentrated. The resulting solid was purified by silica gel column chromatography using chloroform/methanol as a developing solvent to obtain Compound 1-1-b (0.232 g, yield 24%).

Synthesis of Compound 1-1-c
Compound 1-1-b (0.213 g, 0.651 mmol), 35% hydrochloric acid (0.20 mL, 2.10 mmol), acetic acid (3.5 mL), and water (0.9 mL) were mixed and cooled to 0 to 5°C, and a solution of sodium nitrite (67.0 mg, 0.971 mmol) in water (0.1 mL) was added dropwise. The mixture was then stirred for 30 minutes while maintaining the temperature at 0 to 5°C, and a solution of amidosulfuric acid (32.0 mg, 0.330 mmol) in water (0.2 mL) was added to prepare a diazo solution. Meanwhile, N,N-dimethylaniline (0.236 g, 1.95 mmol), sodium acetate (0.320 g, 3.90 mmol), methanol (4.3 mL), and water (4.3 mL) were mixed and cooled to 0 to 5°C, and the entire amount of the diazo solution prepared earlier was added dropwise. After the dropwise addition, the temperature was raised to room temperature, and the precipitated solid was filtered off to obtain compound 1-1-c (0.282 g, yield 94%).

Synthesis of Compound 1-1 Compound 1-1-c (0.260 g, 0.566 mmol), potassium carbonate (0.162 g, 1.17 mmol), methanol (5.0 mL), and tetrahydrofuran (5.0 mL) were mixed and stirred at room temperature for 4 hours. Aqueous ammonium chloride solution was added to the reaction solution to neutralize it, and the organic layer was concentrated, diluted with ethyl acetate, and separated with water and brine. The organic layer was dried over magnesium sulfate and concentrated to obtain a solid. The obtained solid was purified by silica gel column chromatography using chloroform as a developing solvent, and further purified by reprecipitation from chloroform/methanol to obtain Compound 1-1 (0.164 g, yield 69%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) = 13.07 (s, 1H), 8.20 (d, 2H), 8.05 (d, 1H), 7.95-7.92 (m, 4H), 7.59 (dd, 1H), 7.49 (d, 1H), 6.77 (d, 2H), 4.43 (q, 2H), 3.13 (s, 6H), 1.44 (t, 3H).

In compound 1-1, the chemical shift of the hydroxyl group in CDCl ₃ is 13.07 ppm, reflecting the formation of an intramolecular hydrogen bond.

Example 2: Synthesis of compound 1-2 To synthesize compound 1-2, first compound 1-2-a was synthesized, followed by compound 1-2-b, compound 1-2-c, and compound 1-2-d. Compound 1-2 was then obtained by dehydration condensation esterification.

Synthesis of Compound 1-2-a
Sodium bisulfite (78.0 g, 750 mmol) and water (150 mL) were mixed, heated to 70°C, and 37% aqueous formaldehyde solution (44.3 mL, 600 mmol) was added dropwise. After the entire amount was added dropwise, the mixture was cooled to 40°C, and aniline (45.7 mL, 500 mmol) was added dropwise over 1 hour, followed by stirring for 9 hours. The mixture was cooled to 0°C, and the precipitated solid was filtered off to obtain compound 1-2-a (96.0 g, yield 100%).

Synthesis of Compound 1-2-b
4-Amino-2-methoxybenzoic acid (8.36 g, 50.0 mmol), 35% hydrochloric acid (13.2 mL, 150.0 mmol), and water (100 mL) were mixed and cooled to 0 to 5°C, and a solution of sodium nitrite (3.62 g, 52.5 mmol) in water (7.0 mL) was added dropwise. The mixture was then stirred for 4 hours while maintaining the temperature at 0 to 5°C, to prepare a diazo solution. Meanwhile, compound 1-2-a (15.7 g, 75.0 mmol) and water (200 mL) were mixed and cooled to 0 to 5°C, and the entire amount of the diazo solution prepared earlier was added dropwise. After the dropwise addition, the mixture was stirred at 0 to 5°C for 3 hours, then warmed to room temperature and stirred for 16 hours. Sodium hydroxide (24.0 g, 600 mmol) was then added, and the mixture was heated to 90°C and stirred for 2 hours. After cooling to room temperature, hydrochloric acid (52 mL, 589 mmol) was added dropwise, and the precipitated solid was collected by filtration and washed with water to obtain solid Compound 1-2-b, which was subjected to the subsequent diazo coupling without purification.

Synthesis of Compound 1-2-c Compound 1-2-b was mixed with 35% hydrochloric acid (8.8 mL, 100.0 mmol), acetic acid (50.0 mL), and water (50.0 mL) and cooled to 0 to 5°C. To this mixture was added dropwise a solution of sodium nitrite (3.62 g, 52.5 mmol) in water (7.0 mL). The mixture was then stirred for 1 hour while maintaining the temperature at 0 to 5°C, to prepare a diazo solution. Meanwhile, N,N-dimethylaniline (9.08 g, 75.0 mmol), sodium acetate (16.4 g, 200 mmol), methanol (67.0 mL), and water (34.0 mL) were mixed and cooled to 0 to 5°C. The entire amount of the diazo solution prepared earlier was added dropwise. After the dropwise addition, the mixture was stirred at 0 to 5°C for 2 hours, and then the temperature was raised to room temperature. The precipitated solid was collected by filtration and washed with acetonitrile/water to obtain compound 1-2-c (13.9 g, yield based on 4-amino-2-methoxybenzoic acid: 69%).

Synthesis of Compound 1-2-d Compound 1-2-c (13.7 g, 34 mmol), lithium chloride (4.32 g, 100 mmol), N-methyl-2-pyrrolidone (68 mL), and pyridine (22.7 mL) were mixed, heated to 100°C, and stirred for 16 hours. After that, the mixture was cooled to room temperature, and hydrochloric acid (28 mL, 317 mmol) was added dropwise. The precipitated solid was filtered and washed with water to obtain Compound 1-2-d (15.0 g, yield 104%).

Synthesis of Compound 1-2 Compound 1-2-d (6.39 g, 15.0 mmol), 1-butanol (13.8 mL, 150 mmol), DMAP (2.02 g, 16.5 mmol), and tetrahydrofuran (50.0 mL) were mixed, EDC·HCl (4.31 g, 22.5 mmol) was added, and the reaction solution was heated to 50°C and stirred for 4 hours. Water (150 mL) was added to the reaction solution, and the precipitated solid was filtered off and washed with methanol. The obtained solid was purified by silica gel column chromatography using chloroform as a developing solvent and further purified by reprecipitation from chloroform/methanol to obtain compound 1-2 (1.93 g, yield 29%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) = 10.98 (s, 1H), 8.07 (d, 2H), 8.01-7.98 (m, 3H), 7.93 (dd, 2H), 7.52 (d, 1H), 7.45 (dd , 1H), 6.78 (d, 2H), 4.40 (t, 2H), 3.12 (s, 6H), 1.81 (quin, 2H), 1.56-1.47 (m, 2H), 1.01 (t, 3H).

^1H -NMR (400MHz, DMSO- _d6 ): δ (ppm) = 10.78 (br, 1H), 8.08 (d, 2H), 7.99-7.97 (m, 3H), 7.86 (d, 2H), 7.48 (dd, 1H), 7.45 (d , 1H), 6.88 (d, 2H), 4.36 (t, 2H), 3.10 (s, 6H), 1.74 (quin, 2H), 1.50-1.41 (m, 2H), 0.96 (t, 3H)

In compound 1-2, the chemical shift of the hydroxyl group in CDCl ₃ is 10.98 ppm, reflecting the formation of an intramolecular hydrogen bond. Furthermore, the difference in the chemical shift of the hydroxyl group proton (10.78 ppm) between the low-polarity deuterated solvent CDCl ₃ and the high-polarity deuterated solvent DMSO-d ₆ is only 0.2 ppm, also reflecting the formation of an intramolecular hydrogen bond.

Example 3: Synthesis of compound 1-64 Compound 1-64 was obtained by diazo coupling reaction.

Synthesis of Compound 1-64: 4-aminoazobenzene-4'-butylbenzoate (0.595 g, 2.00 mmol), acetic acid (6.00 mL), water (6.00 mL), and 35% hydrochloric acid (0.530 mL, 6.00 mmol) were mixed and cooled to 0°C to 5°C. A solution of sodium nitrite (0.146 g, 2.11 mmol) in water (0.4 mL) was added dropwise to the mixture, and the mixture was stirred for 30 minutes while maintaining the temperature at 0°C to 5°C to prepare a diazo solution. Meanwhile, 3-(dimethylamino)phenol (0.411 g, 2.99 mmol), sodium acetate (0.662 g, 8.07 mmol), water (5.0 mL), and methanol (7.5 mL) were mixed and cooled to 0°C to 5°C. The entire amount of the diazo solution prepared earlier was added dropwise to the mixture, and the mixture was stirred for 1 hour while maintaining the temperature at 0°C to 5°C. The mixture was then warmed to room temperature, and the precipitated solid was collected by filtration. The obtained solid was purified by silica gel column chromatography using chloroform/methanol (99:3) as a developing solvent, and further purified by reprecipitation from chloroform/methanol to obtain compound 1-64 (0.153 g, yield 17%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) = 15.14 (br, 1H), 8.20 (d, 2H), 8.05 (d, 2H), 7.96 (d, 2H), 7.83 (d, 2H), 7.52 (d, 2H), 6.48 (dd, 1H), 6.05 (d, 1H), 4.37 (t, 2H), 3.15 (s, 6H), 1.79 (quin, 2H), 1.56-1.47 (m, 2H), 1.01 (t, 3H).

In compound 1-64, the chemical shift of the hydroxyl group in CDCl ₃ is 15.14 ppm, and it is presumed that an intramolecular hydrogen bond is formed.

Comparative Example 1: Synthesis of Compound C-1 To synthesize Compound C-1, first the above-mentioned Compound 1-2-a was synthesized, followed by dehydration condensation esterification to obtain Compound C-1.

Synthesis of Compound C-1 Compound 1-2-a (0.291 g, 1.01 mmol), 4-n-butylresorcinol (0.199 g, 1.20 mmol), DMAP (76.0 mg, 0.622 mmol), and tetrahydrofuran (10.0 mL) were mixed, EDC·HCl (0.233 g, 1.22 mmol) was added, and the reaction solution was stirred at room temperature for 18 hours. Water was added to the reaction solution, and the precipitated solid was filtered off and washed with methanol. The obtained solid was purified by silica gel column chromatography using chloroform as a developing solvent, and further purified by reprecipitation from water/methanol to obtain Compound C-1 (0.064 g, yield 12%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ (ppm) = 8.18 (t, 1H), 7.92 (d, 2H), 7.73 (dd, 1H), 7.63 (dd, 1H), 7.15 (d, 1H), 6.79-6.72 (m, 4 H), 4.77 (s, 1H), 3.14 (s, 6H), 2.61 (t, 2H), 1.65-1.57 (m, 2H), 1.45-1.36 (m, 2H), 0.96 (t, 3H).

^1H -NMR (400MHz, DMSO- _d6 ): δ (ppm) = 9.64 (br, 1H), 8.19 (t, 1H), 7.87 (d, 2H), 7.76 (dd, 1H), 7.67 (dd, 1H), 7.11 (d, 1H), 6.88 (d, 2H), 6.69 (d, 1H), 6.64 (dd, 1H), 3.12 (s, 6H), 1.53 (quin, 2H), 1.38-1.28 (m, 2H), 0.91 (t, 3H).

Unlike the compounds in the examples, the chemical shift of the hydroxyl group in C-1 in CDCl ₃ is 4.77 ppm, reflecting the absence of intramolecular hydrogen bonds. Furthermore, the difference in the chemical shift of the hydroxyl group proton (9.64 ppm) between the low-polarity deuterated solvent CDCl ₃ and the highly polar deuterated solvent DMSO-d ₆ is large at 4.87 ppm, indicating that the compound is significantly affected by the polarity difference between the deuterated solvents. This also reflects the absence of intramolecular hydrogen bonds.

Example 11: Preparation of composition E11 containing compound 1-1 The following components were mixed and stirred at 80°C for 1 hour to obtain composition E1.
Polymerizable liquid crystal compound (A-6) 75 parts by mass Polymerizable liquid crystal compound (A-7) 25 parts by mass Compound (1-1) 4.0 parts by mass Polymerization initiator: 2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (Irgacure 369; manufactured by BASF Japan Ltd.)
6 parts by mass Leveling agent: polyacrylate compound (BYK-361N; manufactured by BYK-Chemie) 1.2 parts by mass Solvent: o-xylene 250 parts by mass

Polymerizable liquid crystal compound (A-6)

Polymerizable liquid crystal compound (A-7)

The polymerizable liquid crystal compound (A-6) was synthesized by the method described in Lub et al. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996). The polymerizable liquid crystal compound (A-7) was also produced in accordance with this method.

Examples 12 and 13: Preparation of compositions E12 and E13 Compositions E12 and E13 of Examples 12 and 13 were obtained, respectively, in the same manner as in Example 11, except that compounds 1-2 and 1-64 were used instead of compound 1-1.

Comparative Example 1: Preparation of composition C11 Composition C11 of Comparative Example 11 was obtained in the same manner as in Example 11, except that compound C-1, the synthesis method of which was described above, was used instead of compound 1-1.

Manufacture of polarizing plates 1. Formation of alignment film
A glass substrate was used as a transparent substrate. A 2% by mass aqueous solution of polyvinyl alcohol (Polyvinyl Alcohol 1000 fully saponified, manufactured by Wako Pure Chemical Industries, Ltd.) (composition for forming an alignment layer) was applied to the glass substrate by spin coating, and after drying, a film with a thickness of 100 nm was formed. Subsequently, an alignment film was formed by rubbing the surface of the obtained film, thereby obtaining a substrate with an alignment film formed on the glass substrate.

2. Formation of Polarizing Film The composition obtained above was applied by spin coating onto the alignment film of the substrate obtained above, and the applied composition was dried by heating on a hot plate at 120°C for 3 minutes, and then quickly cooled to 70°C or below (the temperature at which the film exhibits a smectic liquid crystal phase upon cooling) to obtain a laminate having a dry film formed on the alignment film.

Next, the dried film was irradiated with ultraviolet light at an exposure dose of 1000 mJ/cm ² (based on 365 nm) using a UV irradiation device (SPOT CURE SP-7; manufactured by Ushio Inc.), thereby polymerizing the polymerizable liquid crystal compound contained in the dried film while maintaining the liquid crystal state of the composition, and a polarizing film was formed from the dried film to obtain a polarizing plate.

<Evaluation>
The dichroic ratio of the resulting polarizing plate was measured as follows. The absorbance (A1) in the transmission axis direction and the absorbance (A2) in the absorption axis direction at the maximum absorption wavelength (λmax) of the polarizing film of the polarizing plate were measured by the double-beam method using a spectrophotometer (Shimadzu Corporation UV-3150) equipped with a folder equipped with a polarizing plate. A mesh that cuts the amount of light by 50% was installed on the reference side of the folder. The ratio (A2/A1) was calculated from the measured values of absorbance (A1) in the transmission axis direction and absorbance (A2) in the absorption axis direction, and this was used as the dichroic ratio (DR). The results are shown in Table 1.

Table 1 shows that a polarizing plate having a film made from a composition containing a compound represented by formula (1) can achieve a high dichroic ratio.

Claims (12)

A composition comprising a compound represented by the following formula (1) and a liquid crystal compound containing at least one of a polymerizable liquid crystal compound and a liquid crystalline polymer compound:
[In formula (1), n represents an integer of 1 or 2.
Ar ¹ , Ar ² and Ar ³ each independently represent a 1,4-phenylene group or a sulfur-containing heterocyclic group, which may have at least one substituent selected from the group consisting of a halogen atom, a hydroxyl group, a methyl group and a methoxy group. At least one of ^{Ar 1} , Ar ² and Ar ³ has at least one hydroxyl group capable of forming an intramolecular hydrogen bond, and the hydroxyl group is directly bonded to the 1,4-phenylene group or the sulfur-containing heterocyclic group.
^R1 represents an alkylamino group which may have a polymerizable group.
When Ar ¹ does not have a hydroxyl group capable of forming an intramolecular hydrogen bond or has a hydroxyl group on the carbon atom adjacent to the carbon atom to which the azo group is bonded, R ² represents at least one group selected from the group consisting of an alkanediyl group having 4 to 20 carbon atoms, an alkanediyloxy group having 2 to 20 carbon atoms, an alkanediyloxycarbonyl group having 2 to 20 carbon atoms, an alkanediylcarbonyl group having 2 to 20 carbon atoms, and an alkanediylcarbonyloxy group having 2 to 20 carbon atoms.
When Ar ¹ has a hydroxyl group capable of forming an intramolecular hydrogen bond on the carbon atom adjacent to the carbon atom to which R ² is bonded, R ² represents a cyclic or chain group having 2 to 20 carbon atoms capable of forming a hydrogen bond with the hydroxyl group.
^R3 represents a polymerizable group or a hydrogen atom.
When n is 2, two Ar ^2s may be the same or different. The composition according to claim 1, wherein the polymerizable liquid crystal compound is a polymerizable smectic liquid crystal compound, and the liquid crystalline polymer compound is a smectic liquid crystalline polymer compound. The composition according to claim 1 or 2, wherein the polymerizable liquid crystal compound comprises a compound represented by the following formula (A):
In formula (A), m represents an integer of 1 to 3.
^X1 , ^X2 , and ^X3 each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group. When m is 2 or 3, multiple ^X1s may be the same or different. At least three selected from the group consisting of ^X1 , ^X2 , and ^X3 represent a divalent 6-membered hydrocarbon ring group.
Y ¹ , Y ² , W ¹ and W ² each independently represent a single bond or a divalent linking group, and when m is 2 or 3, multiple Y ^{1 s} may be the same or different.
^V1 and ^V2 each independently represent an alkanediyl group having 1 to 20 carbon atoms which may have a substituent, in which at least one of _-CH2- constituting the alkanediyl group may be replaced by -O-, -CO-, -S- or -NH-.
^U1 and ^U2 each independently represent a polymerizable group or a hydrogen atom, and at least one of them represents a polymerizable group. The composition according to any one of claims 1 to 3, wherein the compound represented by formula (1) has one hydroxyl group capable of forming an intramolecular hydrogen bond. The composition according to any one of claims 1 to 4, wherein the compound represented by formula (1) has a hydroxyl group in Ar ¹ capable of forming an intramolecular hydrogen bond with R ³ , or a hydroxyl group in Ar ² capable of forming an intramolecular hydrogen bond with -N=N-. A compound represented by the following formula (1a):
In formula (1a), k represents an integer of 1 or 2.
Ar ¹¹ , Ar ¹² , and Ar ¹³ each independently represent a 1,4-phenylene group or a sulfur-containing heterocyclic group which may have at least one substituent selected from the group consisting of a halogen atom, a hydroxyl group, a methyl group, and a methoxy group. At least one of ^{Ar 11} and Ar ¹² has at least one hydroxyl group capable of forming an intramolecular hydrogen bond, and the hydroxyl group is directly bonded to the 1,4-phenylene group or the sulfur-containing heterocyclic group.
R ¹¹ represents an alkylamino group which may have a polymerizable group.
When Ar ¹¹ does not have a hydroxyl group capable of forming an intramolecular hydrogen bond or has a hydroxyl group on the carbon atom adjacent to the carbon atom to which the azo group is bonded, R ¹² represents at least one group selected from the group consisting of an alkanediyl group having 4 to 20 carbon atoms, an alkanediyloxy group having 2 to 20 carbon atoms, an alkanediyloxycarbonyl group having 2 to 20 carbon atoms, an alkanediylcarbonyl group having 2 to 20 carbon atoms, and an alkanediylcarbonyloxy group having 2 to 20 carbon atoms.
When Ar ¹¹ has a hydroxyl group capable of forming an intramolecular hydrogen bond on the carbon atom adjacent to the carbon atom to which R ¹² is bonded, R ¹² represents a cyclic or chain group having 2 to 20 carbon atoms capable of forming a hydrogen bond with the hydroxyl group.
R ¹³ represents a polymerizable group or a hydrogen atom.
When k is 2, two Ar ¹² may be the same or different. The compound according to claim 6, wherein the number of hydroxyl groups capable of forming intramolecular hydrogen bonds is 1. 8. The compound according to claim 6, wherein Ar ¹¹ , Ar ¹² and Ar ¹³ are 1,4-phenylene groups which may have a substituent. The compound according to any one of claims 6 to 8, wherein Ar ¹¹ has a hydroxyl group capable of forming an intramolecular hydrogen bond with R ¹³ , or Ar ¹² has a hydroxyl group capable of forming an intramolecular hydrogen bond with -N=N-. A film formed from the composition described in any one of claims 1 to 5. A laminate comprising the film described in claim 10. A display device comprising the laminate described in claim 11.