Dichroic dye and liquid crystal composition thereof

Abstract

To provide a novel dye compound having a maximum absorption wavelength in a long-wavelength region and having a high dichroic ratio, a liquid crystal composition having good solubility in the dye compound, and a light control element having high transmittance.SOLUTION: A liquid crystal material containing a compound represented by the formula (1) in the figure is used in a polymer-dispersed (polymer-network-type) liquid crystal element or a guest-host-type liquid crystal element, thereby eliminating the need for a polarizing plate and making it possible to obtain a light control element having high transmittance at low cost.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a dichroic dye and a liquid crystal composition thereof. [Background technology]

[0002] Liquid crystal materials are not only used in various display elements that display characters, images, and videos, as typified by TVs and smartphones, but are also being put to practical use as light control elements that adjust the transmission of light. Dye compounds with various properties are used for liquid crystal materials depending on the purpose (for example, Patent Document 1).

[0003] Among liquid crystal materials, those containing dichroic dyes are expected to be used as materials for light-control devices because they eliminate the need for polarizing plates and allow for the production of light-control devices with high transmittance at low cost.

[0004] In recent years, in the fields of building materials and transportation, so-called polymer-dispersed (polymer network) liquid crystal elements and guest-host liquid crystal elements have been attracting attention as light-control elements for smart windows and smart glass that adjust the degree of transmittance of external light to improve spatial comfort and convenience. These elements allow the degree of light transmission / scattering in the liquid crystal layer to be adjusted by applying voltage.

[0005] However, some liquid crystal materials containing dichroic dyes used in the respective light-adjusting elements are not suitable for use in light-adjusting elements depending on the components that make them up, and further improvements in performance are required. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 5,578,419 [Patent Document 2] International Publication No. 2022 / 138418 Summary of the Invention [Problem to be solved by the invention]

[0007] Smart windows and smart glass require high light blocking properties to improve comfort and depending on the environment in which they are used, and the required properties of the dichroic dyes used in liquid crystal materials include a long maximum absorption wavelength (e.g., 605 nm or longer) and a high dichroic ratio.

[0008] An object of the present invention is to provide a novel compound having a maximum absorption wavelength in the long wavelength region and a high dichroic ratio, and a liquid crystal composition containing the compound. [Means for solving the problem]

[0009] Some aspects of the present invention provide the following [1] to [9]. [1] The following formula (1)

[0010] [ka]

[0011] [In formula (1), A 1 , A 2 , A 3 and A 4 are each independently (a) a 1,4-cyclohexylene group and a 1,3-cyclohexylene group (in these groups, one -CH- or two or more non-adjacent -CH- groups may each independently be replaced by -O- or -S-, and the -CH- groups in these groups may each independently be replaced by -NR 5 - may be replaced by ). (b) a 1,4-phenylene group and a 1,3-phenylene group (in these groups, one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=), (c) 1,4-cyclohexenylene group, bicyclo[2.2.2]octane-1,4-diyl group, naphthalene-2,6-diyl group, naphthalene-1,4-diyl group, 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 5,6,7,8-tetrahydronaphthalene-1,4-diyl group, decahydronaphthalene-2,6-diyl group, anthracene-2,6-diyl group, anthracene-1,4-diyl group, anthracene-9,10-diyl group, fluorene-2,7-diyl group or phenanthrene-2, 7-diyl group (one -CH= or two or more non-adjacent -CH= present in a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, a 5,6,7,8-tetrahydronaphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, or a phenanthrene-2,7-diyl group may be replaced by -N=), and (d) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group (one -CH= or two or more non-adjacent -CH= groups in these groups may be replaced by -N=). wherein hydrogen atoms present in the groups (a), (b), (c) and (d) may each independently be replaced by a methyl group, an ethyl group, a propyl group, a 2-propyl group, a butyl group, a 2-butyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a cyano group, a nitro group, a fluorine atom or a chlorine atom; However, there exists A 1 , A 2 , A 3 and A 4at least one of the groups (a), (b), (c), and (d) represents a group selected from the group consisting of the following formulae (Ai-1) to (Ai-4) and (Ap-1) to (Ap-4):

[0012] [ka]

[0013] (In the formula, black dots represent bonds, and R i5 and R i6 are each independently a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, or a linear or branched alkyl group having 1 to 30 carbon atoms (a hydrogen atom present in this group may be replaced by a fluorine atom, and one -CH2- or two or more non-adjacent -CH2- present in this group each independently represent -NR 5 It may be replaced by -, -O-, -S-, -CH=CH-, -CF=CF- or -C≡C-.

[0014] [ka]

[0015] (In the formula, the wavy line and * each represent a bond.) Z 1 and Z 2 each independently represent a single bond, -CH=CH-, -CF=CF-, -N=CH-, -CH=N-, -C≡C-, or a linear or branched alkylene group having 1 to 10 carbon atoms, in which one or more -CH- groups in the alkylene group may be replaced by -O-, -COO-, or -OCO-, and a hydrogen atom present in the alkylene group may be replaced by a fluorine atom, R 1 , R 2 , R 3 and R 4are each independently a hydrogen atom, a fluorine atom, or a linear or branched alkyl group having 1 to 30 carbon atoms (a hydrogen atom present in this group may be replaced by a fluorine atom, and one -CH2- or two or more non-adjacent -CH2- groups present in this group each independently represent -NR 5 -, -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF- or -C≡C-; R 5 represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in these groups may each independently be replaced by -O-, -S-, -COO-, -OCO-, or -CO-, and a hydrogen atom in these groups may be replaced by a fluorine atom).

[0016] m represents an integer of 1 to 3; n represents an integer of 1 to 3; A 1 and A 3 If there are multiple A's, multiple A's 1 and A 3 may be the same or different from each other, Z 1 and Z 2 If there are multiple Z 1 and Z 2 may be the same or different from each other, R 5 If there are multiple R 5 may be the same or different from each other, R i5 and R i6 If there are multiple R i5 and R i6 may be the same or different from each other.

[0017] However, in formula (1), oxygen atoms are not directly bonded to each other.] A compound represented by the formula: [2] The above A 1, A 2 , A 3 and A 4 are each independently represented by the following formulas (a1) to (a6), (b1) to (b11), (c1) to (c8), and (d1) to (d4):

[0018] [ka]

[0019] [ka]

[0020] [In the formula, R e represents a methyl group, an ethyl group, a propyl group, a 2-propyl group, a butyl group, a 2-butyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a cyano group, a nitro group, a fluorine atom, or a chlorine atom, R e If there are multiple R e may be the same group or different groups, The wavy line and * indicate bonds.] is a group selected from the group consisting of groups represented by However, there exists A 1 , A 2 , A 3 and A 4 wherein at least one of the formulas (a1) to (a6), (b1) to (b11), (c1) to (c8), and (d1) to (d4) represents a group selected from the group consisting of formulas (Ai-1) to (Ai-4) and formulas (Ap-1) to (Ap-4). [3] Said Z 1 and Z 2 each independently represent a single bond, —CH═CH—, —CF═CF—, —N═CH—, —CH═N—, —C≡C—, —COO—, or —OCO—. [4] R1 , R 2 , R 3 and R 4 are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR 5 The compound according to any one of [1] to [3], wherein each of the groups is selected from the group consisting of -, -O-, -S-, -COO-, -OCO-, and -CH=CH-. [5] The compound according to any one of [1] to [4], wherein m and n each independently represent an integer of 1 or 2. [6] The formula (1) is represented by the following formula (1A):

[0021] [ka]

[0022] [In formula (1A), A a1 , A a2 , A a3 and A a4 are each independently (a1) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may each independently be replaced by -O- or -S-), (b1) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=), (c1) a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, or a phenanthrene-2,7-diyl group, and (d1) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group wherein hydrogen atoms present in the groups (a1), (b1), (c1) and (d1) may each independently be replaced by a methyl group, an ethyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a fluorine atom or a chlorine atom; However, A a2 and A a4 At least one of the groups (a1), (b1), (c1) and (d1) may be replaced by a group represented by the following formula (Ai-1a) to formula (Ai-4a):

[0023] [ka]

[0024] (In the formula, black dots represent bonds, and R i5a and R i6a are each independently a hydrogen atom, a fluorine atom, a chlorine atom, or a linear or branched alkyl group having 1 to 12 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR a5 -, -O-, -S- or -CH=CH- may be replaced by; Z a1 and Z a2 each independently represents a single bond, —CH═CH—, —CF═CF—, —N═CH—, —CH═N—, —C≡C—, —COO—, or —OCO—; R a1 , R a2 , R a3 and R a4are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR a5 -, -O-, -S-, -COO-, -OCO- or -CH=CH-; R a5 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms (in which one -CH2- or two or more non-adjacent -CH2- groups may each independently be replaced by -O-, -S-, -COO- or -OCO-), m a represents an integer of 1 or 2, n a represents an integer of 1 or 2, A a1 and A a3 If there are multiple A's, multiple A's a1 and A a3 may be the same or different from each other, Z a1 and Z a2 If there are multiple Z a1 and Z a2 may be the same or different from each other, R a5 If there are multiple R a5 may be the same or different from each other, R i5a and R i6a If there are multiple R i5a and R i6a may be the same or different from each other.

[0025] However, in formula (1A), oxygen atoms are not directly bonded to each other.] The compound according to any one of [1] to [5], which is a compound represented by the formula: [7] The formula (1) is represented by the following formula (1B):

[0026] [ka]

[0027] [In formula (1B), A b1 , A b2 , A b3 and A b4 are each independently (a1) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may each independently be replaced by -O- or -S-), (b1) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=), (c1) a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, or a phenanthrene-2,7-diyl group, and (d1) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group wherein hydrogen atoms present in the groups (a1), (b1), (c1) and (d1) may each independently be replaced by a methyl group, an ethyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a fluorine atom or a chlorine atom; However, there exists A b1 , A b2 , A b3 and A b4 At least one of the groups (a1), (b1), (c1) and (d1) represents a group selected from the group consisting of the following formulae (Ap-1) to (Ap-4):

[0028] [ka]

[0029] (In the formula, the wavy line and * each represent a bond.) Z b1 and Z b2 each independently represents a single bond, —CH═CH—, —CF═CF—, —N═CH—, —CH═N—, —C≡C—, —COO—, or —OCO—; R b1 , R b2 , R b3 and R b4 are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR b5 -, -O-, -S-, -COO-, -OCO- or -CH=CH-; R b5 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms (in which one -CH2- or two or more non-adjacent -CH2- groups may each independently be replaced by -O-, -S-, -COO- or -OCO-), m b represents an integer of 1 or 2, n b represents an integer of 1 or 2, A b1 and A b3 If there are multiple A's, multiple A's b1 and A b3 may be the same or different from each other, Z b1 and Z b2 If there are multiple Z b1 and Z b2 may be the same or different from each other, R b5 If there are multiple R b5 may be the same or different from each other.

[0030] However, in formula (1B), oxygen atoms are not directly bonded to each other.] The compound according to any one of [1] to [6], which is a compound represented by the formula: [8] A liquid crystal composition containing the compound according to any one of [1] to [7]. [9] A liquid crystal device comprising a liquid crystal layer formed from the liquid crystal composition according to [8], an electrode, and a substrate supporting the liquid crystal layer and the electrode. [Effects of the Invention]

[0031] According to the present invention, it is possible to provide a novel compound having a maximum absorption wavelength in the long wavelength region and a high dichroic ratio, and a liquid crystal composition containing the compound. DETAILED DESCRIPTION OF THE INVENTION

[0032] Preferred embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments. <Compound> One embodiment of the present invention is a compound represented by the following formula (1) (hereinafter also referred to as "compound (1)"), where in formula (1), oxygen atoms are not directly bonded to each other.

[0033] [ka]

[0034] In formula (1), A 1 , A 2 , A 3 and A 4 each independently represents a group selected from the group consisting of the following group (a), group (b), group (c), and group (d): (a) a 1,4-cyclohexylene group and a 1,3-cyclohexylene group (in these groups, one -CH- or two or more non-adjacent -CH- groups may each independently be replaced by -O- or -S-, and the -CH- groups in these groups may each independently be replaced by -NR 5 - may be replaced by ). where R 5represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in these groups may each independently be replaced by -O-, -S-, -COO-, -OCO-, or -CO-, and a hydrogen atom in these groups may be replaced by a fluorine atom). (b) a 1,4-phenylene group and a 1,3-phenylene group (in these groups, one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=), (c) 1,4-cyclohexenylene group, bicyclo[2.2.2]octane-1,4-diyl group, naphthalene-2,6-diyl group, naphthalene-1,4-diyl group, 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 5,6,7,8-tetrahydronaphthalene-1,4-diyl group, decahydronaphthalene-2,6-diyl group, anthracene-2,6-diyl group, anthracene-1,4-diyl group, anthracene-9,10-diyl group, fluorene-2,7-diyl group, or phenanthrene-2 ,7-diyl group (one —CH= or two or more non-adjacent —CH= present in a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, a 5,6,7,8-tetrahydronaphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, and a phenanthrene-2,7-diyl group may be replaced by —N=). (d) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group (one -CH= or two or more non-adjacent -CH= groups in these groups may be replaced by -N=). The hydrogen atoms present in the groups (a), (b), (c) and (d) may each independently be replaced by a methyl group, an ethyl group, a propyl group, a 2-propyl group, a butyl group, a 2-butyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a cyano group, a nitro group, a fluorine atom or a chlorine atom.

[0035] The group (a) may be, for example, a group selected from the group consisting of groups represented by the following formulae (a1) to (a6), where the wavy line and * each represent a bond.

[0036] [ka]

[0037] The group (b) may be, for example, a group selected from the group consisting of groups represented by the following formulae (b1) to (b12): The wavy lines and * in the formulae (b1) to (b12) have the same meanings as above.

[0038] [ka]

[0039] R in formulas (b2) to (b6) e represents a methyl group, an ethyl group, a propyl group (1-propyl group), a 2-propyl group, a butyl group, a 2-butyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a cyano group, a nitro group, a fluorine atom, or a chlorine atom. e If there are multiple R e may be the same group or different groups.

[0040] The group (c) may be, for example, a group selected from the group consisting of groups represented by the following formulae (c1) to (c8): The wavy lines and * in formulae (c1) to (c8), and R in formulae (c2), (c4), (c5), and (c7) e has the same meaning as above.

[0041] [ka]

[0042] The group (d) may be, for example, a group selected from the group consisting of groups represented by the following formulae (d1) to (d4): The wavy lines and * in the formulae (d1) to (d4) have the same meanings as above.

[0043] [ka]

[0044] In one embodiment, from the viewpoint of easily obtaining a higher dichroic ratio, A 1 , A 2 , A 3 and A 4 are each independently preferably a group selected from the group consisting of groups represented by the above formulae (a1) to (a5), (b1) to (b11), (c1) to (c5), and (d1) to (d4), and more preferably groups represented by the formulae (a1), (b1) to (b3), (c1) to (c3), and (d1).

[0045] In another embodiment, from the viewpoint of compatibility with the liquid crystal composition, A 1 and A 3 is a 1,4-phenylene group or a naphthalene-2,6-diyl group, or A 2 and A 4 is preferably a 1,4-cyclohexylene group, a 1,4-phenylene group, a naphthalene-2,6-diyl group, or a thiophene-2,5-diyl group. 1 and A 3 is a 1,4-phenylene group, and A 2 and A 4 is more preferably a 1,4-cyclohexylene group, a 1,4-phenylene group, a naphthalene-2,6-diyl group, or a thiophene-2,5-diyl group. 2is more preferably a 1,4-phenylene group, a naphthalene-2,6-diyl group, or a thiophene-2,5-diyl group, and particularly preferably a 1,4-phenylene group. Although some of these groups may be substituted with the above-mentioned specific groups, it is preferable that all of the groups are unsubstituted.

[0046] A 1 and A 3 If there are multiple A's, multiple A's 1 and A 3 may be the same or different from each other.

[0047] A 1 , A 2 , A 3 and A 4 At least one of the groups (a), (b), (c) and (d) represents a group selected from the group consisting of formulas (Ai-1) to (Ai-4) and formulas (Ap-1) to (Ap-4) below.

[0048] [ka]

[0049] (In the formula, black dots represent bonds, and R i5 and R i6 are each independently a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, or a linear or branched alkyl group having 1 to 30 carbon atoms (a hydrogen atom present in this group may be replaced by a fluorine atom, and one -CH2- or two or more non-adjacent -CH2- present in this group each independently represent -NR 5 It may be replaced by -, -O-, -S-, -CH=CH-, -CF=CF- or -C≡C-.

[0050] [ka]

[0051] (In the formula, the wavy line and * each represent a bond.) By having at least one group selected from the group consisting of the above formulas (Ai-1) to (Ai-4) and formulas (Ap-1) to (Ap-4), the solubility in the liquid crystal composition is improved due to a moderate breakdown in symmetry, and the extension of the conjugated system in the molecule allows the absorption wavelength to be exhibited in a longer wavelength region.

[0052] The group selected from the group consisting of the above formulae (Ap-1) to (Ap-4) is preferably bonded to the aromatic ring via the bond on the * side, from the viewpoint of effectively widening the electronic conjugation in the molecule and shifting the maximum absorption wavelength to a longer wavelength region.

[0053] From the viewpoint of improving solubility and having a maximum absorption wavelength in the long wavelength region, R i5 and R i6 At least one of the groups is preferably a fluorine atom, a chlorine atom, a cyano group, or a linear or branched alkyl group having 1 to 30 carbon atoms, and is also preferably a methyl group, an ethyl group, a propyl group, a 2-propyl group, a butyl group, a 2-butyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a cyano group, a nitro group, a fluorine atom, or a chlorine atom. In particular, from the viewpoint of shifting the maximum absorption wavelength to a longer wavelength, an electron-donating group is preferred.

[0054] R i5 and R i6 If there are multiple R i5 and R i6 may be the same or different from each other.

[0055] In formula (1), Z 1 and Z 2 each independently represents a single bond, -CH=CH-, -CF=CF-, -N=CH-, -CH=N-, -N=N-, -C≡C-, or an alkylene group having 1 to 10 carbon atoms. One or more -CH2- in the alkylene group may be replaced by -O-, -COO-, or -OCO-. A hydrogen atom present in the alkylene group may be replaced by a fluorine atom.

[0056] The alkylene group having 1 to 10 carbon atoms may be linear or branched, but is preferably linear from the viewpoint of the alignment of the liquid crystal composition. The number of carbon atoms in the alkylene group is preferably 2 to 6, and more preferably 2 to 4. When a portion of the alkylene group is substituted with any of the above-mentioned groups, the number of carbon atoms refers to the total number of carbon atoms including the number of carbon atoms in the substituent.

[0057] The alkylene group having 1 to 10 carbon atoms may be, for example, -CH2O-, -OCH2-, -CF2O-, -OCF2-, -COO-, -OCO-, -CH2CH2-, -CF2CF2-, -OCH2CH2-, -OCH2CH2CH2-, -OCO-CH2-, -OCO-CH2CH2-, -CH2-COO-, -CH2-OCO-, -CH2CH2-OCO-, -OCH2CH2O-, and the like.

[0058] Z 1 and Z 2 From the viewpoint of dichroism and compatibility with the liquid crystal composition, Z is preferably a single bond or -CH=CH-, or, among the alkylene groups having 1 to 10 carbon atoms, an unsubstituted alkylene group or an alkylene group in which one or more -CH2- groups are substituted with -O-, -COO- or -OCO-. 1 and Z 2 is more preferably -CH2CH2-, -COO-, -CH=CH-, -OCH2CH2-, -OCH2CH2CH2-, -OCO-CH2-, -OCO-CH2CH2-, -CH2-COO-, -CH2-OCO-, -CH2CH2-OCO-, or a single bond. 1 and A 3 is a 1,4-phenylene group, a naphthalene-2,6-diyl group, or a thiophene-2,5-diyl group, and Z 1 and Z 2is particularly preferably -CH2CH2-, -COO-, -CH=CH-, -OCH2CH2-, -OCH2CH2CH2-, -OCO-CH2-, -OCO-CH2CH2-, -CH2-COO-, -CH2-OCO-, -CH2CH2-OCO-, or a single bond.

[0059] Z 1 and Z 2 If there are multiple Z 1 and Z 2 may be the same or different from each other.

[0060] In formula (1), R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom or a linear or branched alkyl group having 1 to 30 carbon atoms (a hydrogen atom present in this group may be replaced by a fluorine atom, and one -CH2- or two or more non-adjacent -CH2- present in this group each independently represent -NR 5 may be replaced by -, -O-, -S-, -CH=CH-, -CF=CF- or -C≡C-. 5 has the same meaning as above.

[0061] R 5 If there are multiple R 5 may be the same or different from each other.

[0062] R 1 , R 2 , R 3 and R 4 From the viewpoint of compatibility with the liquid crystal composition, it is preferable that R are each independently a linear or branched alkyl group (including substituted alkyl groups) having 1 to 30 carbon atoms. 1 and R 2 and (b) are preferably unsubstituted linear or branched alkyl groups having 1 to 30 carbon atoms. When a portion of the alkyl group is substituted with any of the above groups, the number of carbon atoms refers to the total number of carbon atoms including the number of carbon atoms in the substituent.

[0063] R 1 and R 2 The number of carbon atoms in R is preferably 1 to 20, and more preferably 1 to 8. 1 Particularly preferred examples include a methyl group, an ethyl group, a propyl group, a butyl group, and a 2-methylbutyl group.

[0064] R 3 and R 4 The number of carbon atoms in R is preferably 2 to 16, and more preferably 4 to 12. 2 Particularly preferred examples include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a 2-ethylhexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tetradecyl group, and a pentadecyl group.

[0065] In formula (1), m and n represent integers of 1 to 3. m and n are preferably 1 or 2, and more preferably 1.

[0066] The compound (1) is preferably a compound represented by the following formula (1A), from the viewpoint of easily obtaining a higher dichroic ratio.

[0067] [ka]

[0068] In formula (1A), A a1 , A a2 , A a3 and A a4 are each independently (a1) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may each independently be replaced by -O- or -S-), (b1) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=), (c1) a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, or a phenanthrene-2,7-diyl group, and (d1) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group wherein hydrogen atoms present in the groups (a1), (b1), (c1) and (d1) may each independently be replaced by a methyl group, an ethyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a fluorine atom or a chlorine atom; However, A a2 and A a4 At least one of the groups (a1), (b1), (c1) and (d1) may be replaced by a group represented by the following formula (Ai-1a) to formula (Ai-4a):

[0069] [ka]

[0070] (In the formula, black dots represent bonds, and R i5a and R i6a are each independently a hydrogen atom, a fluorine atom, a chlorine atom, or a linear or branched alkyl group having 1 to 12 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR a5 -, -O-, -S- or -CH=CH- may be replaced by; Z a1 and Z a2 each independently represents a single bond, —CH═CH—, —CF═CF—, —N═CH—, —CH═N—, —C≡C—, —COO—, or —OCO—; Ra1 , R a2 , R a3 and R a4 are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR a5 -, -O-, -S-, -COO-, -OCO- or -CH=CH-; R a5 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms (in which one -CH2- or two or more non-adjacent -CH2- groups may each independently be replaced by -O-, -S-, -COO- or -OCO-), m a represents an integer of 1 or 2, n a represents an integer of 1 or 2, A a1 and A a3 If there are multiple A's, multiple A's a1 and A a3 may be the same or different from each other, Z a1 and Z a2 If there are multiple Z a1 and Z a2 may be the same or different from each other, R a5 If there are multiple R a5 may be the same or different from each other, R i5a and R i6a If there are multiple R i5a and R i6a may be the same or different from each other.

[0071] However, in formula (1A), oxygen atoms are not directly bonded to each other.

[0072] Among them, it is particularly preferable that the compound (1) is a compound represented by the following formulas (1A-1-1) to (1A-4-4).

[0073] [ka]

[0074] [ka]

[0075] [ka]

[0076] [ka]

[0077] [ka]

[0078] [ka]

[0079] [ka]

[0080] R in formulas (1A-1-1) to (1A-4-4) 1 , R 2 , R 3 and R 4 is R in the above formula (1) 1 , R 2 , R 3 and R 4 is synonymous with R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR5 -, -O-, -S-, -COO-, -OCO- or -CH=CH-), each of which is independently an unsubstituted linear or branched alkyl group having 1 to 20 carbon atoms.

[0081] Compound (1) is preferably a compound represented by the following formula (1B), from the viewpoint of easily obtaining a higher dichroic ratio.

[0082] [ka]

[0083] In formula (1B), A b1 , A b2 , A b3 and A b4 are each independently (a1) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may each independently be replaced by -O- or -S-), (b1) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=), (c1) a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, or a phenanthrene-2,7-diyl group, and (d1) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group wherein hydrogen atoms present in the groups (a1), (b1), (c1) and (d1) may each independently be replaced by a methyl group, an ethyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a fluorine atom or a chlorine atom; However, there exists A b1 , A b2 , A b3 and A b4 At least one of the groups (a1), (b1), (c1) and (d1) represents a group selected from the group consisting of the following formulae (Ap-1) to (Ap-4):

[0084] [ka]

[0085] (In the formula, the wavy line and * each represent a bond.) Z b1 and Z b2 each independently represents a single bond, —CH═CH—, —CF═CF—, —N═CH—, —CH═N—, —C≡C—, —COO—, or —OCO—; R b1 , R b2 , R b3 and R b4 are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR b5 -, -O-, -S-, -COO-, -OCO- or -CH=CH-; R b5 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms (in which one -CH2- or two or more non-adjacent -CH2- groups may each independently be replaced by -O-, -S-, -COO- or -OCO-), m b represents an integer of 1 or 2, n brepresents an integer of 1 or 2, A b1 and A b3 If there are multiple A's, multiple A's b1 and A b3 may be the same or different from each other, Z b1 and Z b2 If there are multiple Z b1 and Z b2 may be the same or different from each other, R b5 If there are multiple R b5 may be the same or different from each other.

[0086] However, in formula (1B), oxygen atoms are not directly bonded to each other.

[0087] Among them, it is particularly preferable that the compound (1) is a compound represented by the following formulas (1B-1-1) to (1B-4-9).

[0088] [ka]

[0089] [ka]

[0090] [ka]

[0091] [ka]

[0092] [ka]

[0093] [ka]

[0094] [ka]

[0095] R in formulas (1B-1-1) to (1B-4-9) 1 , R 2 , R 3 and R 4 is R in the above formula (1) 1 , R 2 , R 3 and R 4 is synonymous with R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one -CH2- or two or more non-adjacent -CH2- groups in this group are each independently -NR 5 -, -O-, -S-, -COO-, -OCO- or -CH=CH-), each of which is independently an unsubstituted linear or branched alkyl group having 1 to 20 carbon atoms.

[0096] Compound (1) can be used, for example, as a liquid crystal material, a light-modulating material, and the like.

[0097] Compound (1) has a high dichroic ratio, making it suitable for use as a dichroic dye in liquid crystal materials. The reason for the high dichroic ratio is not limited to this, but it is presumed that, for example, the increase in the rigid ring structure causes the molecule to elongate in the direction of the transition dipole moment, resulting in a molecular shape closer to that of a rod.

[0098] Compound (1) has a high dichroic ratio. The dichroic ratio of compound (1) is, for example, 3.0 or more, and may be 4.0 or more, or 5.0 or more. The dichroic ratio of compound (1) may be, for example, 3.0 or more and 10.0 or less, 8.0 or less, or 6.0 or less, 4.0 or more and 10.0 or less, 8.0 or less, or 6.0 or less, or 5.0 or more and 10.0 or less, 8.0 or less, or 6.0 or less. The method for measuring the dichroic ratio is as described in the Examples below.

[0099] Compound (1) has a maximum absorption wavelength in the long wavelength region. The maximum absorption wavelength of compound (1) is, for example, 605 nm or more, and may be 630 nm or more or 645 nm or more. Compound (1) may be, for example, a compound having a maximum absorption wavelength between 605 nm or more and 700 nm or less, 680 nm or less, or 660 nm or less, or may be a compound having a maximum absorption wavelength between 630 nm or more and 700 nm or less, 680 nm or less, or 660 nm or more, or may be a compound having a maximum absorption wavelength between 645 nm or more and 700 nm or less, 680 nm or less, or 660 nm or less. The method for measuring the maximum absorption wavelength is as described in the Examples below. (Method of producing the compound) Compound (1) can be produced, for example, by a method including a step x of reacting a compound represented by the following formula (x1) (compound x1) with a compound represented by the following formula (x2) (compound x2) to obtain compound (1). Compound x1 is a known compound or can be produced from a known compound by a known production method.

[0100] [ka]

[0101] [ka]

[0102] Here, R in the above formula 3 , R 4 is R in the above formula (1)3 and R 4 A in the above formula is the same as 2 is A in the above formula (1) 2 and A 4 and R in the above formula 1 is R in the above formula (1) 1 and R 2 is synonymous with X 1 and X 2 represents a halogen atom, which may be a chlorine atom or a bromine atom.

[0103] The conditions for the reaction and post-treatment carried out in step x can be appropriately set depending on the structures of compound x1 and compound x2. For example, compound (1) can be obtained by reacting compound x1 with compound x2 in a reaction mixture containing these. The reaction mixture can further contain one or more of a solvent, a base, and a catalyst, as necessary. Examples of solvents include ethylene glycol, n-butanol, isobutanol, n-pentanol, n-hexanol, N-methyl-pyrrolidone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), toluene, 1,4-dioxane, and ethylene glycol. Examples of bases include sodium carbonate, potassium carbonate, sodium acetate, potassium acetate, sodium hydroxide, potassium hydroxide, pyridine, and triethylamine. Examples of catalysts include palladium chloride, palladium acetate, bis(dibenzylideneacetone)palladium, tris(dibenzylideneacetone)dipalladium, tetrakis(triphenylphosphine)palladium, dichlorobis(triphenylphosphine)palladium, bis(di-tert-butyl(4-dimethylaminophenyl)phosphine)dichloropalladium, copper powder, copper acetate monohydrate, copper chloride, copper bromide, copper iodide, copper sulfate pentahydrate, and tin chloride. Two or more of these solvents, bases, and catalysts may be used in combination. The temperature of the reaction mixture (reaction temperature) may be, for example, 100 to 180°C. The time for which the reaction temperature is maintained (reaction time) may be, for example, 1 to 120 hours. Post-treatment can be performed, for example, by a method including precipitating compound (1), washing the precipitated compound (1), drying the washed compound (1) (e.g., drying under reduced pressure), and purifying the crude product obtained after drying using a silica gel column or the like. Compound (1) can be precipitated by adding, for example, methanol, ethanol, water, or a mixture thereof to the reaction mixture. Compound (1) can be washed with, for example, methanol, ethanol, water, saturated saline, or an aqueous HCl solution (for example, a 5 to 10 w / w % aqueous HCl solution).

[0104] In one embodiment, Z in compound (1) 1 When is a group represented by -C≡C-, compound (1) can also be produced by the method of step a1 shown below.

[0105] Step a1 is a step of reacting compound x1 with a compound represented by the following formula (x3) (compound x3) to obtain a compound represented by the following formula (x4) (compound x4).

[0106] [ka]

[0107] [ka]

[0108] Here, R in the above formula 3 , R 4 is R in the above formula (1) 3 and R 4 A in the above formula is the same as 2 is A in the above formula (1) 2 and A 4 and R in the above formula 1 is R in the above formula (1) 1 and R 2 is synonymous with.

[0109] The conditions for the reaction and post-treatment in step a1 can be appropriately set depending on the structures of compounds x1 and x3. For example, compound x4 can be obtained by reacting compounds x1 and x3 in a reaction mixture containing these compounds. The reaction mixture can further contain one or more of a solvent, a base, and a catalyst, as needed. Examples of the solvent, base, and catalyst include those exemplified in step x. The temperature of the reaction mixture (reaction temperature) can be, for example, 60 to 140°C. The time for maintaining the reaction temperature (reaction time) can be, for example, 1 to 120 hours. The post-treatment can be performed, for example, by a method including precipitating compound x4, washing the precipitated compound x4, and drying (e.g., drying under reduced pressure) the washed compound x4. Precipitation and washing of compound x4 can be performed in the same manner as in step x to obtain compound (1).

[0110] In one embodiment, Z in compound (1) 1 Ga-T a1 A group represented by -COO- (T a1 represents an alkylene group or an alkenyl group. When the formula (1) is (a), compound (1) can also be produced by a method including steps a2 and a3 shown below.

[0111] Step a2 is a step of reacting a compound represented by the following formula (x5) (compound x5) with (meth)acrylic acid to obtain a compound represented by the following formula (x6) (compound x6).

[0112] [ka]

[0113] [ka]

[0114] Here, A in the above formula 2 is A in the above formula (1) 2 and A 4and R in the above formula 1 is R in the above formula (1) 1 and R 2 is synonymous with. T a1 represents an alkylene group or an alkenyl group.

[0115] The conditions for the reaction and post-treatment carried out in step a2 can be appropriately set depending on the structures of compound x5 and compound x6. The reaction mixture can further contain one or more of a solvent, a base, and a catalyst, as needed. The various solvents, bases, and catalysts exemplified in step x can be used. The temperature of the reaction mixture (reaction temperature) can be, for example, 100 to 120°C. The time for which the reaction temperature is maintained (reaction time) can be, for example, 1 to 48 hours. Furthermore, the alkenyl group can be converted to an alkyl group by catalytic hydrogen reduction using palladium carbon. Post-treatment can be carried out by a method including purifying the crude product obtained after drying using a silica gel column or the like.

[0116] Step a3 is a step of reacting a compound represented by the following formula (x7) (compound x7) with a compound represented by the above formula (x6) (compound x6) to obtain a compound (compound x8).

[0117] [ka]

[0118] [ka]

[0119] Here, R in the above formula 3 , R 4 is R in the above formula (1) 3 and R 4 A in the above formula is the same as 2 is A in the above formula (1) 2 and A 4 and R in the above formula 1is R in the above formula (1) 1 and R 2 is synonymous with.

[0120] The conditions for the reaction and post-treatment carried out in step a3 can be appropriately set depending on the structures of compounds x6 and x7. For example, compound x6 and compound x7 can be reacted under esterification conditions to give compound (x8). The temperature of the reaction mixture (reaction temperature) may be, for example, 0 to 80°C. The time for which the reaction temperature is maintained (reaction time) may be, for example, 1 to 120 hours. Post-treatment can be performed, for example, by a method including precipitating compound x8, washing the precipitated compound x7, drying the washed compound x8 (e.g., drying under reduced pressure), and purifying the crude product obtained after drying using a silica gel column or the like. Precipitation and washing of compound x8 can be performed in the same manner as in step x. <Liquid Crystal Composition> One embodiment of the present invention is a liquid crystal composition containing compound (1). The liquid crystal composition contains compound (1) and a liquid crystal component, and may further contain other components in addition to these components.

[0121] The content of compound (1) may be 0.1 parts by mass or more, 0.5 parts by mass or more, or 1 part by mass or more, relative to 100 parts by mass of the total amount of liquid crystal components in the liquid crystal composition, from the viewpoints of light-blocking property and light resistance when the voltage is off. The content of compound (1) may be 15 parts by mass or less, 8 parts by mass or less, or 5 parts by mass or less, relative to 100 parts by mass of the total amount of liquid crystal components in the liquid crystal composition, from the viewpoints of solubility and transparency when the voltage is on. From these viewpoints, the content of compound (1) may be 0.1 to 15 parts by mass, 0.5 to 8 parts by mass, or 1 to 5 parts by mass, relative to 100 parts by mass of the total amount of liquid crystal components in the liquid crystal composition.

[0122] Compound (1) may be contained in the liquid crystal composition as a dichroic dye. In other words, the liquid crystal composition may contain a dichroic dye containing compound (1). The liquid crystal composition may contain a dichroic dye other than compound (1). The number of types of dichroic dyes contained in the liquid crystal composition may be 1 to 6, or may be 1 to 5, or 1 to 4. When multiple types of dichroic dyes are used, it is preferable that the multiple types of dichroic dyes have different maximum absorption wavelengths. This makes it possible to adjust the color to a desired color, such as black. The liquid crystal composition may further contain at least one selected from the group consisting of red dye compounds having a maximum absorption wavelength in the range of 500 to 600 nm and yellow dye compounds having a maximum absorption wavelength in the range of 400 to 500 nm, and preferably further contains both the red dye compound and the yellow dye compound.

[0123] The content (total amount) of the dichroic dye may be 0.2 parts by mass or more, 0.5 parts by mass or more, or 1.0 parts by mass or more, relative to 100 parts by mass of the total amount of the liquid crystal components in the liquid crystal composition, from the viewpoints of light-blocking property and light fastness when the voltage is off. The content (total amount) of the dichroic dye may be 15 parts by mass or less, 13 parts by mass or less, or 10 parts by mass or less, relative to 100 parts by mass of the total amount of the liquid crystal components in the liquid crystal composition, from the viewpoints of solubility of the dichroic dye and transparency when the voltage is off. From these viewpoints, the content (total amount) of the dichroic dye may be 0.2 to 15 parts by mass, 0.5 to 15 parts by mass, or 0.3 to 13 parts by mass, relative to 100 parts by mass of the total amount of the liquid crystal components in the liquid crystal composition. (liquid crystal component) The liquid crystal component is a component consisting of one or more liquid crystal compounds. The liquid crystal component includes a compound (2). The compound (2) is, for example, a non-polymerizable liquid crystal compound and is represented by the following formula (2).

[0124] [ka]

[0125] In formula (2), R 11represents an alkyl group having 1 to 10 carbon atoms (a hydrogen atom present in this group may be replaced by a fluorine atom, and one -CH2- or two or more non-adjacent -CH2- groups present in this group may each independently be replaced by -CH=CH-, -C≡C-, -O-, -CO-, -COO-, or -OCO-), R 12 represents a halogen atom, a cyano group, an isothiocyanate group, or an alkyl group having 1 to 10 carbon atoms (a hydrogen atom present in the alkyl group may be replaced with a fluorine atom, and one -CH- or two or more non-adjacent -CH- groups present in the alkyl group may each independently be replaced with -CH=CH-, -C≡C-, -O-, -CO-, -COO-, or -OCO-), A 11 , A 12 and A 13 are each independently (a3) a 1,4-cyclohexylene group (in which one —CH— or two or more non-adjacent —CH— groups may be replaced by —O—), (b3) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=); and (c3) a 1,4-cyclohexenyl group, a tetrahydropyran-2,5-diyl group, a 1,3-dioxane-2,5-diyl group, a decahydronaphthalene-2,6-diyl group, a pyridine-2,5-diyl group, a pyrimidine-2,5-diyl group, a pyrazine-2,5-diyl group, a naphthalene-2,6-diyl group, or a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group (one -CH= or two or more non-adjacent -CH= groups in the naphthalene-2,6-diyl group and the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced with -N=). wherein hydrogen atoms present in the groups (a3), (b3) and (c3) may each independently be replaced by a cyano group, a methyl group, a trifluoromethyl group, a trifluoromethyloxy group, a fluorine atom or a chlorine atom; Z11 and Z 12 each independently represents a single bond, -CH2CH2-, -(CH2)4-, -OCH2-, -CHO-, -COO-, -OCO-, -OCF2-, -CF2O-, -CH=NN=CH-, -CH=CH-, -CF=CF- or -C≡C-; n 11 represents an integer from 0 to 3, A 11 and Z 11 If there are multiple A's, multiple A's 11 may be the same or different, and multiple Z 11 may be the same or different from each other.

[0126] R 11 is preferably an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, or an alkenyloxy group having 2 to 8 carbon atoms, is preferably an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms, is more preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, is still more preferably an alkyl group having 2 to 5 carbon atoms or an alkenyl group having 2 to 3 carbon atoms, and is particularly preferably an alkyl group having 2 to 5 carbon atoms.

[0127] R 11 When reliability is important, R is preferably an alkyl group. 11 In order to stabilize the nematic phase, the total number of carbon atoms and oxygen atoms is preferably 5 or less, and the structure is preferably linear.

[0128] R 12 is preferably a fluorine atom, a cyano group, or an alkyl group having 1 to 5 carbon atoms (in the alkyl group, one -CH2- or two or more non-adjacent -CH2- may be replaced by -O-).

[0129] A 11 , A 12 and A 13Each of A preferably independently represents a group selected from the group consisting of the above group (a3) ​​and group (b3). 13 is preferably a group (b3), and more preferably a group having a structure represented by the following formula (b3-1):

[0130] [ka]

[0131] R i3 , R i4 and R i5 each independently represents a hydrogen atom or a fluorine atom. 12 The wavy line represents the bond to Z. 12 Represents a bond to .

[0132] A 13 When A is the group (b3), in the case where it is required to increase the refractive index anisotropy (Δn), 11 and A 12 is preferably aromatic. In order to improve the response speed, A 11 and A 12 is preferably aliphatic. 11 and A 12 preferably each independently represent a trans-1,4-cyclohexylene group (in this group, one -CH- or two or more non-adjacent -CH- groups may be replaced with -O-, and in this group, -CH= may be replaced with -N=), or a 1,4-phenylene group, a 2-fluoro-1,4-phenylene group, a 3-fluoro-1,4-phenylene group, a 3,5-difluoro-1,4-phenylene group, or a 2,3-difluoro-1,4-phenylene group (in these groups, one -CH= or two or more non-adjacent -CH= groups may be replaced with -N=).

[0133] Among them, A 11 and A 12 More preferably, each independently represents one of the following structures:

[0134] [ka]

[0135] The bond represented by the wavy line in the above structure is R 11 The bond on the side is R 12 It is the connecting hand on the side.

[0136] A 11 and A 12 More preferably, each independently represents one of the following structures: In the following structures, the wavy line and * have the same meanings as above.

[0137] [ka]

[0138] n 11 is preferably 0, 1 or 2. When emphasis is placed on improving Δε, n 11 is preferably 0 or 1. When importance is placed on the transition temperature (Tni), n 11 is preferably 1 or 2.

[0139] The compound (2) may be used singly or in combination of two or more. For example, two, three, four, five, six, seven, eight, or nine types of compound (2) may be used in combination, or even ten or more types may be used in combination. There is no particular limitation on the types of compounds that can be combined, and they are used in combination depending on the desired performance, such as solubility at low temperature, transition temperature, electrical reliability, and birefringence.

[0140] When the liquid crystal composition further contains a polymerizable compound and a polymerization initiator, the content of compound (2) may be 25% by mass or more, 35% by mass or more, or 45% by mass or more based on the total amount of the liquid crystal component, polymerizable compound, and polymerization initiator in the liquid crystal composition, from the viewpoints of scattering properties and low-voltage driving. The content of compound (2) may be 80% by mass or less, 70% by mass or less, or 60% by mass or less based on the total amount of the liquid crystal component, polymerizable compound, and polymerization initiator in the liquid crystal composition, from the viewpoints of scattering properties and reliability. From these viewpoints, the content of compound (2) may be 25 to 80% by mass, 35 to 70% by mass, or 45 to 60% by mass based on the total amount of the liquid crystal component, polymerizable compound, and polymerization initiator in the liquid crystal composition.

[0141] The compound (2) is a liquid crystal compound having a positive dielectric anisotropy (Δε) at 25° C. (so-called p-type liquid crystal compound) or a liquid crystal compound having a dielectric anisotropy (Δε) of approximately 0 (so-called non-polar liquid crystal compound).

[0142] In one embodiment, compound (2) may be a compound represented by the formula (2): 12 is a cyano group (hereinafter referred to as a "cyan liquid crystal compound").

[0143] In the cyan liquid crystal compound, Z in formula (2) 11 and Z 12 are each independently preferably a single bond, -COO-, -OCO-, or -CH2-CH2-, and more preferably a single bond or -COO-.

[0144] In the cyan liquid crystal compound, R 11 The number of carbon atoms is preferably 2 to 7, and more preferably 2 to 5.

[0145] In the cyan liquid crystal compound, n in formula (2) 11 is preferably 0 or 1.

[0146] Specific preferred examples of the cyan liquid crystal compound include compounds represented by the following formulas (vi-1) to (vi-11).

[0147] [ka]

[0148] In the above formulas (vi-1) to (vi-11), R 51 represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and Y 11 ~Y 64 Each of Y independently represents a hydrogen atom or a fluorine atom. 11 ~Y 64 may all represent hydrogen atoms, or one or more of them may represent a fluorine atom.

[0149] More specific examples of the cyan liquid crystal compound include compounds represented by the following formulas (vi-A) to (vi-G).

[0150] [ka]

[0151] In the above formulas (vi-A) to (vi-G), R 511 represents an alkyl group having 2 to 7 carbon atoms or an alkoxy group having 2 to 7 carbon atoms, and preferably represents an alkyl group having 2 to 5 carbon atoms or an alkoxy group having 2 to 5 carbon atoms.

[0152] More specific examples of the cyan liquid crystal compound include compounds represented by the following formulas (2C-1) to (2C-18).

[0153] [ka]

[0154] [ka]

[0155] [ka]

[0156] [ka]

[0157] [ka]

[0158] The cyan liquid crystal compounds may be used singly or in combination of two or more.

[0159] The content of the cyan liquid crystal compound may be 5% by mass or more, 10% by mass or more, 15% by mass or more, 20% by mass or more, or 25% by mass or more, based on the total amount of the liquid crystal components in the liquid crystal composition, and may be 100% by mass or less, 97% by mass or less, or 95% by mass or less, based on the total amount of the liquid crystal components in the liquid crystal composition.

[0160] In one embodiment, the cyan liquid crystal compound may be used in combination with a compound that does not fall under the category of cyan liquid crystal compounds. The compounds that do not fall under the category of cyan liquid crystal compounds may be used alone or in combination of two or more.

[0161] Examples of compounds that do not fall under the category of cyan liquid crystal compounds include compounds (2) in which R 12 is an alkyl group (including substituted ones) having 1 to 10 carbon atoms, and Z in formula (2) 12 is —COO—. Specific examples of such compounds include one or more of the compounds represented by the following formulae (2M-1) to (2M-3).

[0162] [ka]

[0163] The content of the compounds not corresponding to the cyan liquid crystal compounds may be 20% by mass or more, 30% by mass or more, 40% by mass or more, or 60% by mass or more based on the total amount of the liquid crystal components in the liquid crystal composition. The content of the cyan liquid crystal compounds may be 90% by mass or less, 80% by mass or less, or 70% by mass or less based on the total amount of the liquid crystal components in the liquid crystal composition.

[0164] The liquid crystal component may contain a liquid crystal compound other than compound (2). The content of the liquid crystal compound other than compound (2) is preferably 10 mass % or less based on the total amount of the liquid crystal component in the liquid crystal composition.

[0165] The transition temperature (Tni) of the liquid crystal component (total liquid crystal compound) is preferably 95°C or higher, more preferably 100 to 150°C, and even more preferably 130 to 140°C. Here, the transition temperature (Tni) refers to the temperature (upper limit temperature) at which the liquid crystal component (liquid crystal phase) undergoes a phase transition from a nematic phase to an isotropic phase. The higher the transition temperature (Tni), the more likely it is that the nematic phase can be maintained even at high temperatures, and the wider the operating temperature range can be.

[0166] The refractive index anisotropy (Δn) of the liquid crystal component at 25° C. and 589 nm is preferably from 0.15 to 0.35, more preferably from 0.18 to 0.32, and even more preferably from 0.20 to 0.30. (Polymerizable component) The liquid crystal composition may or may not contain a polymerizable component. The polymerizable component is a component consisting of one or more polymerizable compounds. When the liquid crystal composition contains a polymerizable component, the polymerizable compound in the liquid crystal composition polymerizes to form a polymer network that disperses the liquid crystal component. According to the liquid crystal composition, polymerizable compounds can be polymerized to form polymer-dispersed (polymer network) liquid crystals. Therefore, the liquid crystal composition can be called a polymer-dispersed (polymer network) liquid crystal-forming composition. Furthermore, since the liquid crystal composition contains a liquid crystal component that serves as a host and a dichroic dye that serves as a guest, it can also be called a guest-host (GH) liquid crystal material.

[0167] The polymerizable compound is a compound having a polymerizable group, and has radical polymerizability, cation polymerizability, or anion polymerizability. The polymerizable compound is preferably a (meth)acrylate. Here, "(meth)acrylate" means at least one of an acrylate and its corresponding methacrylate. (Polymerization initiator) The polymerization initiator is used to polymerize the polymerizable compound. The polymerization initiator is preferably a photopolymerization initiator used when polymerization is carried out by light irradiation. As the photopolymerization initiator, one that generates an active species corresponding to the polymerizability of the polymerizable compound may be used, and for example, a photoradical polymerization initiator or a photocationic polymerization initiator may be used. As the photopolymerization initiator, a known and commonly used one may be used. (additive ingredients) To the liquid crystal composition, polymerization inhibitors, antioxidants, light stabilizers, chain transfer agents, pigments, particles with a particle size of less than 1 μm, chiral compounds, or alignment materials can be added as long as the practical electro-optical properties and adhesion when a liquid crystal element is produced are not impaired. Among these, it is preferable to use at least one selected from the group consisting of polymerization inhibitors, antioxidants, light stabilizers, particles with a particle size of less than 1 μm, and pigments. These additives can be known and commonly used, and for example, the compounds described in WO 2022 / 138418 can be used in the same amount. <Liquid crystal layer> Another embodiment of the present invention is a liquid crystal layer formed from the liquid crystal composition of the above embodiment. When the liquid crystal composition contains a polymerizable component, the liquid crystal layer contains the dichroic dye, a polymer network derived from the polymerizable compound, and a liquid crystal component containing the compound (2). The polymer network is composed of a polymer of the polymerizable component (a polymer containing, as a monomer unit, each of the polymerizable compounds exemplified as the polymerizable component). The content of the first to fourth components relative to the total amount of polymerizable components in the liquid crystal composition can be interpreted as the content of monomer units derived from each component relative to the total amount (total mass) of polymers in the liquid crystal layer. Furthermore, the content of the polymerizable component relative to the total amount of the liquid crystal composition can be interpreted as the content of polymer relative to the total amount of the liquid crystal layer.

[0168] Since the liquid crystal layer contains a polymer network and a liquid crystal component, it can be referred to as a layer made of polymer-dispersed (polymer network) liquid crystal (polymer-dispersed liquid crystal layer). A polymer-dispersed (polymer network) liquid crystal layer has, for example, a structure in which the liquid crystal component forms a continuous layer in a three-dimensional polymer network structure, a structure in which droplets of the liquid crystal component are dispersed in the polymer, or a structure in which both are mixed. A polymer-dispersed (polymer network) liquid crystal layer has a structure in which the liquid crystal component is encapsulated in the polymer component, a structure in which a three-dimensional network structure of the polymer component is formed in a continuous phase of the liquid crystal component, or a structure in which both are mixed. A structure in which a three-dimensional network structure of the polymer component is formed in a continuous phase of the liquid crystal component is preferred. The average particle size of the encapsulated liquid crystal component and the average gap spacing of the three-dimensional network structure of the polymer component are preferably 0.1 μm or more, more preferably 0.2 μm or more, most preferably 0.3 μm or more, and preferably 3 μm or less, more preferably 2 μm or less, and most preferably 1 μm or less. In the liquid crystal layer, the liquid crystal component and the polymer network are phase-separated from each other, and therefore the liquid crystal layer can also be called a phase-separated liquid crystal layer.

[0169] The liquid crystal layer can be obtained, for example, by a method including applying a liquid crystal composition onto a substrate. When the liquid crystal composition includes a polymerizable component, the method may further include polymerizing the polymerizable component after applying the liquid crystal component. <Liquid crystal elements and light control elements> Another embodiment of the present invention is a liquid crystal element comprising at least a liquid crystal layer, electrodes, and a substrate supporting the liquid crystal layer and the electrodes. Since the liquid crystal layer is the liquid crystal layer of the above embodiment (polymer-dispersed (polymer network) liquid crystal layer), this liquid crystal element is a so-called polymer-dispersed (polymer network) liquid crystal element.

[0170] For example, when no voltage is applied, the liquid crystal element can be in a light-scattering state due to the polymer network derived from the polymerizable compound and the liquid crystal molecules (liquid crystal components) present in the voids therein. On the other hand, when a voltage is applied, the liquid crystal molecules are oriented perpendicular to the substrate, thereby enabling the element to be in a light-transmitting state. Thus, the liquid crystal element can change its light-transmitting state depending on whether or not a voltage is applied. In particular, since the liquid crystal layer contains a dichroic dye that aligns with the liquid crystal molecules when a voltage is applied, it can exhibit a color corresponding to the absorption wavelength of the dichroic dye when no voltage is applied. By combining multiple dichroic dyes, the element can also be in a light-blocking state when no voltage is applied. Therefore, the liquid crystal element can be used as a liquid crystal light-control element incorporated into a device requiring a light-control function, or as a liquid crystal display element used in a video display.

[0171] The liquid crystal element is preferably used, for example, in building materials, light-controlling glass, automotive smart windows, or light-controlling units in OLED displays. The liquid crystal element can be used for the same applications as conventional polymer-dispersed liquid crystal display elements, and is particularly preferably used in transmissive displays, flexible displays, etc. More specifically, the liquid crystal element can be used in products such as architectural light-controlling elements such as windows, skylights, roofs, walls, partitions, dividers, and doors; transportation light-controlling elements such as doors, windows, doors, helmets, and sunroofs; decorative light-controlling elements such as sunglasses, eyeglasses, sun visors, watches, mirrors, and reflectors; and display components such as flexible liquid crystal display elements, reflective liquid crystal display elements, transparent liquid crystal display elements, and variable diffusion films. [Example]

[0172] The present invention will be described in further detail below with reference to examples, but the present invention is not limited to these examples. Furthermore, "parts" in the compositions of the following examples and comparative examples means "parts by mass." Example 1 (Synthesis of compound a-1)

[0173] [ka]

[0174] Red-254 (10 g), potassium carbonate (12 g), 1-bromo-2-ethylhexyl (16 g), and 400 mL of acetonitrile were added to a reaction vessel and reacted at 90°C for 12 hours. After the reaction solution was allowed to cool, water (400 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol, and dried under reduced pressure to obtain compound a-1, a compound represented by the above formula (a-1). The yield was 11 g. (Synthesis of dichroic dye A)

[0175] [ka]

[0176] Under an inert gas atmosphere, compound a-1 (11 g), compound a-2 (11.8 g) represented by the above formula (a-2), potassium carbonate (8 g), 1,4-dioxane (150 mL), and water (20 mL) were added to a reaction vessel and stirred. Bis(di-tert-butyl(4-dimethylaminophenyl)phosphine)dichloropalladium(II) (430 mg) was added and the mixture was heated to 90 °C and reacted for 5 hours. After completion of the reaction, the reaction solution was allowed to cool, and water (400 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol, and dried under reduced pressure. The resulting crude product was purified using a silica gel column (toluene / ethyl acetate = 20:1) to obtain the compound represented by the following formula (A) as dichroic dye A. The yield was 12.2 g. The mass spectral assignments for dichroic dye A are shown below. MS m / z: 942 [M + ]

[0177] [ka]

[0178] <Example 2> (Synthesis of dichroic dye B)

[0179] [ka]

[0180] The same procedure as in Example 1 was carried out, except that compound a-3 (13.3 g) represented by the above formula (a-3) was used instead of compound a-2 (11.8 g) in Example 1, to obtain the compound represented by the following (B) as dichroic dye B. The yield was 10.1 g. The mass spectral assignments of dichroic dye B are shown below. MS m / z: 1009 [M + ]

[0181] [ka]

[0182] Example 3 (Synthesis of compound a-4)

[0183] [ka]

[0184] A reaction vessel under an inert atmosphere was charged with 3.2 g of sodium hydride and 150 mL of N-methylpyrrolidinone (NMP). The reaction vessel was cooled to below 10°C, and 3,6-di(2-thienyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione (10 g) was added in two portions and stirred for 1 hour. Then, a solution of 21 g of 1-iodododecane in NMP (50 mL) was slowly added dropwise. After the addition was completed, the reaction was allowed to proceed for 12 hours. After allowing the reaction solution to cool, water (400 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol, and dried under reduced pressure to obtain compound a-4, a compound represented by the above formula (a-4). The yield was 16 g. (Synthesis of compound a-5)

[0185] [ka]

[0186] Under an inert gas atmosphere, compound a-4 (16 g) and 150 mL of dichloromethane were added to a reaction vessel, and 12 g of N-bromosuccinimide was added in three portions at room temperature, followed by stirring and reaction. After completion of the reaction, the organic phase was washed with saturated aqueous ammonium chloride, the solvent was distilled off, and the mixture was dried under reduced pressure. The resulting crude product was purified using a silica gel column (dichloromethane) to obtain compound a-5, a compound represented by the above formula (a-5). The yield was 20 g. (Synthesis of dichroic dye C)

[0187] [ka]

[0188] Under an inert gas atmosphere, compound a-5 (20 g), compound a-6 (16.4 g) represented by the above formula (a-6), potassium carbonate (12 g), 1,4-dioxane (250 mL), and water (40 mL) were added to a reaction vessel and stirred. Bis(di-tert-butyl(4-dimethylaminophenyl)phosphine)dichloropalladium(II) (600 mg) was added and the mixture was heated to 90 °C for 5 hours. After completion of the reaction, the reaction solution was allowed to cool, and water (400 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol, and dried under reduced pressure. The resulting crude product was purified using a silica gel column (toluene / ethyl acetate = 20:1) to obtain the compound represented by the following formula (C) as dichroic dye C. The yield was 21 g. The mass spectral assignments for dichroic dye C are shown below. MS m / z: 1038[M + ]

[0189] [ka]

[0190] Example 4 (Synthesis of dichroic dye D)

[0191] [ka]

[0192] The same procedure as in Example 3 was carried out, except that compound a-7 (13 g) represented by the above formula (a-7) was used instead of compound a-6 (16.4 g) in Example 3, to obtain a compound represented by the following (D) as dichroic dye D. The yield was 21 g. The mass spectral assignments of dichroic dye D are shown below. MS m / z: 924 [M + ]

[0193] [ka]

[0194] <Example 5> (Synthesis of dichroic dye E)

[0195] [ka]

[0196] The same procedure as in Example 3 was carried out, except that compound a-8 (14 g) represented by the above formula (a-8) was used instead of compound a-6 (16.4 g) in Example 3, to obtain a compound represented by the following (E) as dichroic dye E. The yield was 25 g. The mass spectral assignments of dichroic dye E are shown below. MS m / z: 952 [M + ]

[0197] [ka]

[0198] Example 6 (Synthesis of dichroic dye F)

[0199] [ka]

[0200] The same procedure as in Example 3 was carried out, except that compound a-9 (17 g) represented by the above formula (a-9) was used instead of compound a-6 (16.4 g) in Example 3, to obtain a compound represented by the following formula (F) as dichroic dye F. The yield was 22 g. The mass spectral assignments of dichroic dye F are shown below. MS m / z: 892 [M + ]

[0201] [ka]

[0202] Example 7 (Synthesis of compound a-10)

[0203] [ka]

[0204] A reaction vessel under an inert atmosphere was charged with 3.2 g of sodium hydride and 150 mL of N-methylpyrrolidinone (NMP). The reaction vessel was cooled to below 10°C, and 10 g of 3,6-di(2-thienyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione was added in two portions and stirred for 1 hour. Then, a solution of 15 g of diethylene glycol 2-bromoethyl methyl ether 2-[2-(2-methoxyethoxy)ethoxy]ethyl bromide in NMP (30 mL) was slowly added dropwise. After the addition was complete, the reaction was allowed to proceed for 12 hours. After allowing the reaction solution to cool, water (400 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol, and dried under reduced pressure to obtain compound a-10, a compound represented by the above formula (a-10). The yield was 13 g. (Synthesis of compound a-11)

[0205] [ka]

[0206] Under an inert gas atmosphere, compound a-10 (13 g) and 150 mL of dichloromethane were added to a reaction vessel, and 10 g of N-bromosuccinimide was added in three portions at room temperature, followed by stirring and reaction. After the reaction was completed, the organic phase was washed with saturated aqueous ammonium chloride, the solvent was distilled off, and the mixture was dried under reduced pressure. The resulting crude product was purified using a silica gel column (dichloromethane) to obtain compound a-11, a compound represented by the above formula (a-11). The yield was 14.5 g. (Synthesis of dichroic dye G)

[0207] [ka]

[0208] Under an inert gas atmosphere, compound a-11 (14.5 g), compound a-12 (19 g) represented by the above formula (a-12), potassium carbonate (9 g), 1,4-dioxane (250 mL), and water (40 mL) were added to a reaction vessel and stirred. Bis(di-tert-butyl(4-dimethylaminophenyl)phosphine)dichloropalladium(II) (500 mg) was added and the mixture was heated to 90 °C for 5 hours. After completion of the reaction, the reaction solution was allowed to cool, and water (400 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with acetone, and dried under reduced pressure. The resulting crude product was purified using a silica gel column (toluene / ethyl acetate = 9:1) to obtain the compound represented by the following formula (G) as dichroic dye G. The yield was 16 g. The mass spectral assignments for dichroic dye B are shown below. MS m / z: 1190[M + ]

[0209] [ka]

[0210] Example 9 (Synthesis of compound a-13)

[0211] [ka]

[0212] Under an inert gas atmosphere, a reaction vessel was charged with 5-bromo-2-propyl-2,3-dihydro-1H-indene (24 g), copper iodide (0.76 g), bistriphenylphosphine palladium dichloride (1.4 g), 200 mL of tetrahydrofuran, and 50 mL of triethylamine, heated to 60 °C, and stirred. Tetramethylsilylacetylene (9.5 g) was then slowly added dropwise, and the reaction was allowed to proceed for 3 hours. After the reaction was complete, water was added and the mixture was extracted with ethyl acetate. The organic phase was washed with saturated brine, and the solvent was concentrated. The concentrated solution was transferred to a reaction vessel, and 200 mL of methanol and potassium carbonate (35 g) were added. The reaction was allowed to proceed for 2 hours at 60 °C. After the reaction was complete, water was added, extracted with toluene, and dried under reduced pressure. The resulting crude product was purified using a silica gel column (hexane) to obtain compound a-13, a compound represented by the above formula (a-13). The yield was 16.5 g. (Synthesis of compound a-14)

[0213] [ka]

[0214] Under an inert gas atmosphere, 1-bromo-2-fluoro-4-iodobenzene (27 g), copper iodide (0.7 g), bistriphenylphosphine palladium dichloride (1.2 g), 200 mL of tetrahydrofuran, and 50 mL of triethylamine were charged into a reaction vessel and stirred at room temperature. A solution of compound a-13 (13 g) in 20 mL of tetrahydrofuran was slowly added dropwise, and the mixture was stirred for 3 hours. After the reaction was completed, water was added and the mixture was extracted with ethyl acetate. The organic phase was washed with saturated brine, and the solvent was concentrated. The concentrated solution was transferred to a 500 mL autoclave, and 50 mL of ethanol, 200 mL of tetrahydrofuran, and 1.5 g of 5% platinum carbon were added, followed by catalytic hydrogenation. After the reaction was completed, the reaction solution was filtered, the filtrate was concentrated, and the resulting crude product was purified using a silica gel column (toluene) to obtain compound a-14, a compound represented by the above formula (a-14). The yield was 27 g. (Synthesis of compound a-15)

[0215] [ka]

[0216] Under an inert gas atmosphere, compound a-14 (27 g), bis-pinacolatodiborane (23 g), potassium acetate (11 g), bistriphenylphosphine palladium dichloride (1.4 g), and 250 mL of N,N-dimethylformamide were charged into a reaction vessel and reacted at 90°C for 5 hours. After the reaction was completed, water was added and the mixture was extracted with ethyl acetate. The organic phase was washed with saturated brine, and the solvent was concentrated. The resulting crude product was purified using a silica gel column (toluene) to obtain compound a-15, a compound represented by the above formula (a-15). The yield was 26 g. (Synthesis of dichroic dye H)

[0217] [ka]

[0218] Under an inert gas atmosphere, compound a-15 (26 g), compound a-16 (26 g) represented by the above formula (a-16), potassium carbonate (13.5 g), 1,4-dioxane (350 mL), and water (50 mL) were added to a reaction vessel and stirred. Bis(di-tert-butyl(4-dimethylaminophenyl)phosphine)dichloropalladium(II) (700 mg) was added and the mixture was heated to 90 °C for 5 hours. After the reaction was completed, the reaction solution was allowed to cool, and water (600 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with acetone, and dried under reduced pressure. The resulting crude product was purified using a silica gel column (toluene / ethyl acetate = 9:1) to obtain the compound represented by the following formula (H) as dichroic dye G. The yield was 24 g. The mass spectral assignments for dichroic dye H are shown below. MS m / z: 1309 [M + ]

[0219] [ka]

[0220] Example 10 (Synthesis of dichroic dye I)

[0221] [ka]

[0222] Under an inert gas atmosphere, compound a-13 (10 g), compound a-17 (15 g) represented by the above formula (a-17), copper iodide (0.4 g), bistriphenylphosphinepalladium dichloride (0.7 g), 200 mL of N,N-dimethylformamide, and 50 mL of triethylamine were added to a reaction vessel, heated to 90°C, and reacted for 5 hours. After completion of the reaction, the reaction solution was allowed to cool, and water (600 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with acetone, and dried under reduced pressure. The resulting crude product was purified using a silica gel column (toluene / ethyl acetate = 9:1) to obtain the compound represented by the following formula (I) as dichroic dye I. The yield was 12 g. The mass spectral assignments of dichroic dye H are shown below. MS m / z: 820 [M + ]

[0223] [ka]

[0224] <Comparative Example 1> As the dichroic dye J, a compound represented by the following formula (J) was prepared.

[0225] [ka]

[0226] <Comparative Example 2> As the dichroic dye K, a compound represented by the following formula (K) was prepared.

[0227] [ka]

[0228] <Evaluation 1: Maximum absorption wavelength and dichroic ratio> The maximum absorption wavelengths and dichroic ratios of the dichroic dyes A to I obtained above were measured by the following method. The results are shown in Table 1. (Preparation of test panels) A measurement sample was prepared by adding 1.0 part by mass of a dichroic dye to 100 parts by mass of a liquid crystal composition H having the following composition (the unit "%" in the structural formula below means "% by mass"). Next, two 2 cm x 2 cm glass substrates with ITO electrode layers each having an ITO electrode layer and a horizontal alignment film formed on the ITO electrode layer were prepared. The horizontal alignment film was fabricated using AL1051 manufactured by JSR Corporation. The two glass substrates with ITO electrode layers were then arranged with the ITO electrode layer facing the inside of the cell to prepare a cell equipped with an injection port. The cell thickness was adjusted to 3.5 μm using plastic particles. A measurement sample was injected into the cell, and a test panel (device) for testing was prepared by sealing the injection port with a sealant. [Composition of Liquid Crystal Composition H]

[0229] [ka]

[0230] (Measurement of maximum absorption wavelength) Using a spectrometer (manufactured by Otsuka Electronics Co., Ltd., "LCD-5200"), the absorption spectrum between 350 and 750 nm was measured using the above test panel at 25°C with no applied voltage, to determine the maximum absorption wavelength of the dichroic dye. (dichroic ratio measurement) Using linearly polarized light as the light source of the transmittance meter, the transmittance (A0) at the maximum absorption wavelength when the orientation direction of the test panel was parallel to the linearly polarized light, and the transmittance (A90) at the maximum absorption wavelength when the orientation direction was perpendicular to the linearly polarized light were measured. Using these transmittances, the dichroic ratio (R) was calculated using the following formula.

[0231] Dichroic ratio (R) = Transmittance (A0) / Transmittance (A90) <Evaluation 2: Solubility> The solubilities of the dichroic dyes A to K obtained above were evaluated by the following method. The results are shown in Table 1.

[0232] Liquid crystal compositions were prepared containing 1% by mass of the dichroic dyes A to I obtained in the examples and the dichroic dyes J to K used as comparative examples in a 99% by mass liquid crystal composition H. 0.5 g of the prepared liquid crystal composition was weighed into a 1 mL sample bottle (manufactured by Maruemu Co., Ltd.), which was then purged with dry nitrogen and capped. The liquid crystal composition was stored in a temperature-controlled thermostatic chamber (manufactured by Espec Corporation, SH-241) at 20°C for one week. Crystalline crystals were visually inspected daily for crystallization. A rating of ◯ was given for no crystallization after one week, a ⊚ was given for no crystallization after two weeks, and an × was given for crystallization after one week.

[0233] [Table 1]

Claims

1. The following formula (1) 【Chemistry 1】 [In formula (1), A １ , A ２ , A ３ and A ４ are each independently (a) 1,4-cyclohexylene group and 1,3-cyclohexylene group (one —CH ) present in these groups ２ - or two or more non-adjacent -CH ２ Each - may be independently replaced by -O- or -S-, and -CH- in these groups may be replaced by -NR ５ - may be replaced with .) (b) a 1,4-phenylene group and a 1,3-phenylene group (in these groups, one —CH= or two or more non-adjacent —CH= groups may be replaced by —N=); (c) 1,4-cyclohexenylene group, bicyclo[2.2.2]octane-1,4-diyl group, naphthalene-2,6-diyl group, naphthalene-1,4-diyl group, 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 5,6,7,8-tetrahydronaphthalene-1,4-diyl group, decahydronaphthalene-2,6-diyl group, anthracene-2,6-diyl group, anthracene-1,4-diyl group, anthracene-9,10-diyl group, fluorene-2,7-diyl group or phenanthrene-2, 7-diyl group (one -CH= or two or more non-adjacent -CH= present in a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, a 5,6,7,8-tetrahydronaphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, or a phenanthrene-2,7-diyl group may be replaced by -N=), and (d) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group (one —CH= or two or more non-adjacent —CH= groups in these groups may be replaced by —N=). wherein hydrogen atoms present in the groups (a), (b), (c) and (d) may each independently be replaced by a methyl group, an ethyl group, a propyl group, a 2-propyl group, a butyl group, a 2-butyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a cyano group, a nitro group, a fluorine atom or a chlorine atom; However, there exists A １ , A ２ , A ３ and A ４ at least one of the following represents a group selected from the group consisting of formulas (Ai-1) to (Ai-4) and formulas (Ap-1) to (Ap-4) instead of the groups (a), (b), (c), and (d): 【Chemistry 2】 (wherein the formula, black dots represent bonds, R ｉ５ and R ｉ６ are each independently a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, or a linear or branched alkyl group having 1 to 30 carbon atoms (a hydrogen atom in this group may be replaced by a fluorine atom, and one —CH ２ - or two or more non-adjacent -CH ２ Each - is independently -NR ５ It may be replaced by -, -O-, -S-, -CH=CH-, -CF=CF- or -C≡C-. 【Transformation 3】 (In the formula, the wavy line and * each represent a bond.) Z １ and Z ２ each independently represents a single bond, -CH=CH-, -CF=CF-, -N=CH-, -CH=N-, -C≡C-, or a linear or branched alkylene group having 1 to 10 carbon atoms, and one or more -CH ２ - may be replaced by -O-, -COO-, or -OCO-, and a hydrogen atom in the alkylene group may be replaced by a fluorine atom; R １ , R ２ , R ３ and R ４ are each independently a hydrogen atom, a fluorine atom, or a linear or branched alkyl group having 1 to 30 carbon atoms (a hydrogen atom in this group may be replaced by a fluorine atom, and one —CH ２ - or two or more non-adjacent -CH ２ Each - is independently -NR ５ may be replaced by -, -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF- or -C≡C-; R ５ represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms (one —CH ２ - or two or more non-adjacent -CH ２ Each - may be independently replaced by -O-, -S-, -COO-, -OCO- or -CO-, and a hydrogen atom in these groups may be replaced by a fluorine atom. m represents an integer of 1 to 3; n represents an integer of 1 to 3; A １ and A ３ If there are multiple A's, １ and A ３ may be the same or different from each other, Z １ and Z ２ If there are multiple Z １ and Z ２ may be the same or different from each other, R ５ If there are multiple R ５ may be the same or different from each other, R ｉ５ and R ｉ６ If there are multiple R ｉ５ and R ｉ６ may be the same or different from each other. However, in formula (1), oxygen atoms are not directly bonded to each other.] A compound represented by the formula:

2. The above A １ , A ２ , A ３ and A ４ are each independently represented by the following formulae (a1) to (a6), (b1) to (b11), (c1) to (c8), and (d1) to (d4): 【Chemistry 4】 【Transformation 5】 [In the formula, R ｅ represents a methyl group, an ethyl group, a propyl group, a 2-propyl group, a butyl group, a 2-butyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a cyano group, a nitro group, a fluorine atom, or a chlorine atom, R ｅ If there are multiple R ｅ may be the same group or different groups, The wavy line and * each represent a bond.] is a group selected from the group consisting of groups represented by However, there exists A １ , A ２ , A ３ and A ４ wherein at least one of the formulas (a1) to (a6), (b1) to (b11), (c1) to (c8), and (d1) to (d4) represents a group selected from the group consisting of formulas (Ai-1) to (Ai-4) and formulas (Ap-1) to (Ap-4).

3. Said Z １ and Z ２ each independently represents a single bond, —CH═CH—, —CF═CF—, —N═CH—, —CH═N—, —C≡C—, —COO—, or —OCO—.

4. The R １ , R ２ , R ３ and R ４ are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one —CH ２ - or two or more non-adjacent -CH ２ Each - is independently -NR ５ The compound according to claim 1 or 2, wherein the aryl group is -, -O-, -S-, -COO-, -OCO- or -CH=CH-.

5. The compound according to claim 1 or 2, wherein m and n each independently represent an integer of 1 or 2.

6. The formula (1) is represented by the following formula (1A): 【Transformation 6】 [In formula (1A), A ａ１ , A ａ２ , A ａ３ and A ａ４ are each independently (a1) 1,4-cyclohexylene group (one —CH ２ - or two or more non-adjacent -CH ２ Each - may be independently replaced by -O- or -S-.) (b1) a 1,4-phenylene group (one -CH= or two or more non-adjacent -CH= groups in the group may be replaced by -N=); (c1) a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, or a phenanthrene-2,7-diyl group, and (d1) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group wherein hydrogen atoms present in the groups (a1), (b1), (c1) and (d1) may each independently be replaced by a methyl group, an ethyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a fluorine atom or a chlorine atom; However, A ａ２ and A ａ４ At least one of the groups (a1), (b1), (c1) and (d1) is a group represented by the following formula (Ai-1a) to formula (Ai-4a): 【Transformation 7】 (wherein the formula, black dots represent bonds, R ｉ５ａ and R ｉ６ａ are each independently a hydrogen atom, a fluorine atom, a chlorine atom, or a linear or branched alkyl group having 1 to 12 carbon atoms (one —CH ２ - or two or more non-adjacent -CH ２ Each - is independently -NR ａ５ and (iii) a group selected from the group consisting of: Z ａ１ and Z ａ２ each independently represents a single bond, —CH═CH—, —CF═CF—, —N═CH—, —CH═N—, —C≡C—, —COO—, or —OCO—, R ａ１ , R ａ２ , R ａ３ and R ａ４ are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one —CH ２ - or two or more non-adjacent -CH ２ Each - is independently -NR ａ５ may be replaced by -, -O-, -S-, -COO-, -OCO- or -CH=CH-; R ａ５ represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms (one —CH ２ - or two or more non-adjacent -CH ２ Each - may be independently replaced by -O-, -S-, -COO- or -OCO-; m ａ represents an integer of 1 or 2, n ａ represents an integer of 1 or 2, A ａ１ and A ａ３ If there are multiple A's, ａ１ and A ａ３ may be the same or different from each other, Z ａ１ and Z ａ２ If there are multiple Z ａ１ and Z ａ２ may be the same or different from each other, R ａ５ If there are multiple R ａ５ may be the same or different from each other, R ｉ５ａ and R ｉ６ａ If there are multiple R ｉ５ａ and R ｉ６ａ may be the same or different from each other. However, in formula (1A), oxygen atoms are not directly bonded to each other.] The compound according to claim 1, which is a compound represented by the formula:

7. The formula (1) is represented by the following formula (1B): 【Transformation 8】 [In formula (1B), A ｂ１ , A ｂ２ , A ｂ３ and A ｂ４ are each independently (a1) 1,4-cyclohexylene group (one —CH ２ - or two or more non-adjacent -CH ２ Each - may be independently replaced by -O- or -S-.) (b1) a 1,4-phenylene group (one -CH= or two or more non-adjacent -CH= groups in the group may be replaced by -N=); (c1) a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, an anthracene-2,6-diyl group, an anthracene-1,4-diyl group, an anthracene-9,10-diyl group, a fluorene-2,7-diyl group, or a phenanthrene-2,7-diyl group, and (d1) a thiophene-2,5-diyl group, a thiophene-2,4-diyl group, a benzothiophene-2,5-diyl group, a benzothiophene-2,6-diyl group, a dibenzothiophene-3,7-diyl group, a dibenzothiophene-2,6-diyl group, or a thieno[3,2-b]thiophene-2,5-diyl group wherein hydrogen atoms present in the groups (a1), (b1), (c1) and (d1) may each independently be replaced by a methyl group, an ethyl group, a methoxy group, an ethoxy group, a methylthio group, an ethylthio group, a dimethylamino group, a diethylamino group, a fluorine atom or a chlorine atom; However, there exists A ｂ１ , A ｂ２ , A ｂ３ and A ｂ４ At least one of the groups (a1), (b1), (c1) and (d1) represents a group selected from the group consisting of the following formulas (Ap-1) to (Ap-4): 【Chemistry 9】 (In the formula, the wavy line and * each represent a bond.) Z ｂ１ and Z ｂ２ each independently represents a single bond, —CH═CH—, —CF═CF—, —N═CH—, —CH═N—, —C≡C—, —COO—, or —OCO—, R ｂ１ , R ｂ２ , R ｂ３ and R ｂ４ are each independently a hydrogen atom, a fluorine atom, a linear or branched alkyl group having 1 to 30 carbon atoms (one —CH ２ - or two or more non-adjacent -CH ２ Each - is independently -NR ｂ５ may be replaced by -, -O-, -S-, -COO-, -OCO- or -CH=CH-; R ｂ５ represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms (one —CH ２ - or two or more non-adjacent -CH ２ Each - may be independently replaced by -O-, -S-, -COO- or -OCO-; m ｂ represents an integer of 1 or 2, n ｂ represents an integer of 1 or 2, A ｂ１ and A ｂ３ If there are multiple A's, ｂ１ and A ｂ３ may be the same or different from each other, Z ｂ１ and Z ｂ２ If there are multiple Z ｂ１ and Z ｂ２ may be the same or different from each other, R ｂ５ If there are multiple R ｂ５ may be the same or different from each other. However, in formula (1B), oxygen atoms are not directly bonded to each other.] The compound according to claim 1, which is a compound represented by the formula:

8. A liquid crystal composition comprising the compound according to claim 1 or 2.

9. A liquid crystal device comprising: a liquid crystal layer formed from the liquid crystal composition according to claim 8; electrodes; and a substrate supporting the liquid crystal layer and the electrodes.

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