Compound, liquid crystal composition, and liquid crystal device

Abstract

To provide a novel compound that has a maximum absorption wavelength in the long-wavelength region and exhibits a high dichroic ratio.SOLUTION: The invention provides a compound represented by the formula (1) in the figure.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a compound, a liquid crystal composition, and a liquid crystal device. [Background technology]

[0002] Liquid crystal materials are not only used in various display elements that display characters, images, and videos, such as those on 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 elements, because they eliminate the need for polarizing plates and enable the production of light control elements 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 type liquid crystal elements have been attracting attention as light control elements for smart windows and smart glass that adjust the degree of external light transmission to improve spatial comfort and convenience. The degree of light transmission / scattering in the liquid crystal layer can be adjusted by applying a voltage.

[0005] However, some liquid crystal materials containing dichroic dyes used in the respective light control elements are not suitable for use in light control 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. Pat. 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. Therefore, 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

[10] .

[0010] [1] The following formula (1) [ka] [In formula (1), A 1 and A 2 are each independently (a) 1,4-cyclohexylene group and 1,3-cyclohexylene group (one -CH 2 - or two or more non-adjacent -CH 2 Each - may be independently replaced by -O- or -S-, and -CH- in these groups is -NR 3 - may be replaced by .) (b) a 1,4-phenylene group and a 1,3-phenylene group (in which 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=s in these groups may be replaced by -N=). and 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; 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, 2- 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 and R 2 each independently represents 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 -CH 2 - or two or more non-adjacent -CH 2 - is independently -NR 3 -, -O-, -S-, -CH=CH-, -CF=CF- or -C≡C-; R 3 is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 20 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; n represents an integer of 1 to 3; A 2 If there are multiple A's, multiple A's 2 may be the same or different, Z 2 If there are multiple Z 2 may be the same or different, R 3 If there are multiple R 3 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:

[0011] [2] The following formula (1A) [ka] [In formula (1A), A 1 , A 2 , Z 1 , Z 2 , R 1 and R 2 has the same meaning as above.] The compound according to [1],

[0012] [3] The above A 1 and the above A 2 are each independently represented by the following formulae (a1), (b1) to (b12), and (d1) to (d4): [ka] [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, there are multiple R e may be the same group or different groups, A 1 In this case, the wavy line indicates a bond to NH, and * indicates Z 1 indicates the bond to A 2 In this case, the wavy line is Z 1 indicates a bond to Z. 2 ] The compound according to [1] or [2], wherein the R is a group selected from the group consisting of groups represented by the following formula:

[0013] [4] The above A 1 is the 1,4-phenylene group or the 1,3-phenylene group, 2 is the 1,4-cyclohexylene group, the 1,4-phenylene group, the naphthalene-2,6-diyl group, or the thiophene-2,5-diyl group.

[0014] [5] The above A 1 wherein R is the 1,4-phenylene group.

[0015] [6] Said Z 1 represents a single bond, -CH=CH-, or an alkylene group having 1 to 10 carbon atoms, and one or more -CH 2 The compound according to any one of [1] to [5], wherein - may be substituted by -O-, -COO- or -OCO-.

[0016] [7] The above A 2 is the 1,4-phenylene group, the naphthalene-2,6-diyl group, or the thiophene-2,5-diyl group, and Z 1 Ga-CH 2 CH 2 -, -COO-, -CH=CH-, -OCH 2 CH 2 -, -OCH 2 CH 2 CH 2 -, -OCO-CH 2 -, -OCO-CH 2 CH 2 -, -CH 2 -COO-, -CH 2 -OCO-, -CH 2 CH 2 The compound according to any one of [1] to [6], which is -OCO- or a single bond.

[0017] [8] R 1 and the above R 2 are each independently the linear or branched alkyl group having 1 to 30 carbon atoms.

[0018] [9] A liquid crystal composition comprising the compound according to any one of [1] to [8].

[0019]

[10] A liquid crystal device comprising a liquid crystal layer formed from the liquid crystal composition according to [9], an electrode, and a substrate supporting the liquid crystal layer and the electrode. Effect of the Invention

[0020] 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 PREFERRED EMBODIMENTS

[0021] Preferred embodiments of the present invention will be described below, however, the present invention is not limited to the following embodiments.

[0022] <Compound> One embodiment of the present invention is a compound represented by the following formula (1) (hereinafter also referred to as "compound (1)"), in which, however, no oxygen atom is directly bonded to another oxygen atom in formula (1). [ka]

[0023] In formula (1), A 1 and A 2 each independently represents a group selected from the group consisting of the following group (a), group (b), group (c) and group (d).

[0024] (a) 1,4-cyclohexylene group and 1,3-cyclohexylene group (one -CH 2 - or two or more non-adjacent -CH 2 Each - may be independently replaced by -O- or -S-, and -CH- in these groups is -NR 3 - may be substituted.)

[0025] Here, R 3 is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 20 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.

[0026] (b) a 1,4-phenylene group and a 1,3-phenylene group (in these groups, one -CH= or two or more non-adjacent -CH= may be replaced by -N=).

[0027] (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=s 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=).

[0028] (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=s in these groups may be replaced by -N=).

[0029] 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.

[0030] The group (a) may be, for example, a group selected from the group consisting of groups represented by the following formulas (a1) to (a6). 1 In the formulae (a1) to (a6), the wavy line indicates a bond to NH, and * indicates Z 1 The bond to the group (a) is shown. 2 In this case, the wavy lines in formulas (a1) to (a6) represent Z 1 indicates a bond to Z. 2 indicates the bond to. [ka]

[0031] 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 line and * in the formulae (b1) to (b12) have the same meanings as above. [ka]

[0032] R in formulas (b2) to (b6) e R 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, there are multiple R e may be the same group or different groups.

[0033] The group (c) may be, for example, a group selected from the group consisting of groups represented by the following formulae (c1) to (c14). The wavy lines and * in the formulae (c1) to (c14), and R in the formulae (c2) to (c6) and (c8) to (d14) e has the same meaning as above. [ka]

[0034] The group (d) may be, for example, a group selected from the group consisting of groups represented by the following formulae (d1) to (d10). The wavy lines and * in the formulae (d1) to (d10), and R e has the same meaning as above. [ka]

[0035] In one embodiment, in order to easily obtain a higher dichroic ratio, A 1 and A 2 are preferably each independently selected from the group consisting of the groups represented by the above formulas (a1), (b1) to (b12), and (d1) to (d4), and more preferably the groups represented by the formulas (a1), (b1) to (b3), (b12), and (d1).

[0036] In another embodiment, from the viewpoint of compatibility with the liquid crystal composition, A 1 is a 1,4-phenylene group or a 1,3-phenylene group, or A 2 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 is a 1,4-phenylene group or a 1,3-phenylene group, 2 More preferably, A is a 1,4-cyclohexylene group, a 1,4-phenylene group, a naphthalene-2,6-diyl group, or a thiophene-2,5-diyl group. 1 More preferably, A is a 1,4-phenylene 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.

[0037] A 2 If there are multiple A's, multiple A's 2 may be the same or different from each other.

[0038] 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. 2 - may be replaced by -O-, -COO- or -OCO-. A hydrogen atom present in the alkylene group may be replaced by a fluorine atom.

[0039] 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 part of the alkylene group is replaced with any of the above-mentioned groups, the above carbon number means the total number of carbon atoms including the number of carbon atoms in the substituent.

[0040] The alkylene group having 1 to 10 carbon atoms is, for example, -CH 2 O-, -OCH 2 -, -CF 2 O-, -OCF 2 -, -COO-, -OCO-, -CH 2 CH 2 -, -CF 2 CF 2 -, -OCH 2 CH 2 -, -OCH 2 CH 2 CH 2-, -OCO-CH 2 -, -OCO-CH 2 CH 2 -, -CH 2 -COO-, -CH 2 -OCO-, -CH 2 CH 2 -OCO-, -OCH 2 CH 2 It may be O-, etc.

[0041] Z 1 and Z 2 From the viewpoint of dichroism and compatibility with the liquid crystal composition, represents a single bond or -CH=CH-, or represents an unsubstituted alkylene group or one or more -CH 2 From the same viewpoint, Z is preferably an alkylene group substituted with -O-, -COO- or -OCO-. 1 and Z 2 -CH 2 CH 2 -, -COO-, -CH=CH-, -OCH 2 CH 2 -, -OCH 2 CH 2 CH 2 -, -OCO-CH 2 -, -OCO-CH 2 CH 2 -, -CH 2 -COO-, -CH 2 -OCO-, -CH 2 CH 2 More preferably, A is -OCO- or a single bond. 2 is a 1,4-phenylene group, a naphthalene-2,6-diyl group, or a thiophene-2,5-diyl group; Z 1 Ga-CH 2 CH 2 -, -COO-, -CH=CH-, -OCH 2 CH 2 -, -OCH 2 CH 2 CH 2 -, -OCO-CH 2 -, -OCO-CH 2 CH 2-, -CH 2 -COO-, -CH 2 -OCO-, -CH 2 CH 2 Particularly preferred is -OCO- or a single bond. 2 Z directly bonded to 2 is preferably a single bond.

[0042] Z 2 If there are multiple Z 2 may be the same or different from each other.

[0043] In formula (1), R 1 and R 2 each independently represents 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 -CH 2 - or two or more non-adjacent -CH 2 - is independently -NR 3 In this case, R may be replaced by -, -O-, -S-, -CH=CH-, -CF=CF- or -C≡C-. 3 has the same meaning as above.

[0044] R 3 If there are multiple R 3 may be the same or different from each other.

[0045] R 1 and R 2 From the viewpoint of compatibility with the liquid crystal composition, it is preferable that R is each independently a linear or branched alkyl group (including substituted alkyl groups) having 1 to 30 carbon atoms. 1 and R 2 and each are preferably an unsubstituted linear or branched alkyl group having 1 to 30 carbon atoms. When a part of the alkyl group is substituted with any of the above groups, the above carbon number means the total number of carbon atoms including the number of carbon atoms in the substituent.

[0046] R 1 The number of carbon atoms in R is preferably 1 to 20, and more preferably 1 to 8. 1 Particularly preferred examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, and a 2-methylbutyl group.

[0047] R 2 The number of carbon atoms in R is preferably 2 to 16, and more preferably 4 to 12. 2 Particularly preferred specific 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.

[0048] In formula (1), n ​​represents an integer of 1 to 3. n is preferably 1 or 2, and more preferably 1.

[0049] From the viewpoint of easily obtaining a higher dichroic ratio, compound (1) is preferably a compound represented by the following formula (1A). [ka]

[0050] In formula (1A), A 1 , A 2 , Z 1 , Z 2 , R 1 and R 2 is A in the above formula (1). 1 , A 2 , Z 1 , Z 2 , R 1 and R 2 is synonymous with.

[0051] In one embodiment, compound (1) is represented by formula (1A), 1 is a 1,4-phenylene group or a 1,3-phenylene group, 2 is a 1,4-phenylene group, a naphthalene-2,6-diyl group, or a thiophene-2,5-diyl group; Z1 and Z 2 are each independently -CH 2 CH 2 -, -COO-, -CH=CH-, -OCH 2 CH 2 -, -OCH 2 CH 2 CH 2 -, -OCO-CH 2 -, -OCO-CH 2 CH 2 -, -CH 2 -COO-, -CH 2 -OCO-, -CH 2 CH 2 -OCO- or a single bond, R 1 and R 2 are each preferably independently a linear or branched alkyl group having 1 to 30 carbon atoms. 1 and A 2 is a specific group (e.g., R e R 1 and R 2 are each preferably an unsubstituted linear or branched alkyl group having 1 to 30 carbon atoms. Among them, it is particularly preferable that compound (1) is a compound represented by the following formulas (1A-1) to (1A-11). [ka] [ka] [ka] [ka]

[0052] R in formulas (1A-1) to (1A-11) 1 and R 2 is R in the above formula (1). 1 and R 2In formula (1A-11), R e is R in the above formula (b3) e Synonymous with R. 1 and R 2 are preferably each independently an unsubstituted linear or branched alkyl group having 1 to 20 carbon atoms. 2 More preferably, is an n-butyl group.

[0053] The compound (1) can be used, for example, as a liquid crystal material, a light-adjusting material, etc.

[0054] Compound (1) has a high dichroic ratio, and is therefore suitable as a dichroic dye for use in liquid crystal materials. The reason for the high dichroic ratio is not limited to the above, 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.

[0055] 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.

[0056] 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 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 less, or 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.

[0057] (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 in accordance with a known production method. [ka] [ka]

[0058] Here, A in the above formula 1 , A 2 , Z 1 , Z 2 , R 1 , R 2 and n is A in the above formula (1). 1 , A 2 , Z 1 , Z 2 , R 1 、 R 2 and n, X 1 represents a halogen atom. The halogen atom may be a chlorine atom or a bromine atom.

[0059] The conditions of the reaction and post-treatment carried out in the step x can be appropriately set according to the structures of the compound x1 and the compound x2. For example, the compound (1) can be obtained by reacting the compound x1 and the compound x2 in a reaction mixture containing them. The reaction mixture can further contain at least one of a solvent, a base, and a catalyst, as necessary. Examples of the solvent include ethylene glycol, normal butanol, isobutanol, normal pentanol, normal hexanol, N-methyl-pyrrolidone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), toluene, 1,4-dioxane, and ethylene glycol. Examples of the base include sodium carbonate, potassium carbonate, sodium acetate, potassium acetate, sodium hydroxide, potassium hydroxide, pyridine, and triethylamine. Examples of the catalyst 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 (reaction time) for maintaining the reaction temperature may be, for example, 1 to 120 hours. The post-treatment may be performed by a method including, for example, precipitating compound (1), washing the precipitated compound (1), drying the washed compound (1) (for example, 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 mixed solvent thereof to the reaction mixture. Compound (1) can be washed with, for example, methanol, ethanol, water, saturated saline, an aqueous HCl solution (for example, a 5 to 10 w / w% aqueous HCl solution), or the like.

[0060] In one embodiment, Z in compound (1) 1 -R a1 -OCO-R a2 - (R a1 and R a2 each independently represents an alkylene group or a single bond.), compound (1) can also be produced by a method including the following steps a1 and a2.

[0061] 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). [ka] [ka]

[0062] Here, A in the above formula 1 and R 1 is A in the above formula (1). 1 and R 1 is synonymous with R a1 represents an alkylene group or a single bond.

[0063] The conditions of the reaction and post-treatment carried out in step a1 can be appropriately set according to the structures of compound x1 and compound x3. For example, compound x4 can be obtained by reacting compound x1 and compound x3 in a reaction mixture containing them. The reaction mixture can further contain at least one of a solvent, a base, and a catalyst as necessary. As the solvent, base, and catalyst, 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 180° C. The time for which the reaction temperature is maintained (reaction time) can be, for example, 1 to 120 hours. The post-treatment can be carried out by a method including, for example, precipitating compound x4, washing the precipitated compound x4, and drying (for example, drying under reduced pressure) the washed compound x4. Precipitation and washing of compound x4 can be carried out in the same manner as in step x.

[0064] Step a2 is a step of reacting compound x4 with a compound (compound x5) represented by the following formula (x5) to obtain compound (1). [ka]

[0065] Here, A in the above formula (x5) 2 , Z 2 , R 2 , and n is A in the above formula (1). 2 , Z 2 , R 2 , and n are synonymous with R a2 represents an alkylene group or a single bond; X 2 represents a hydroxy group or a halogen atom. The halogen atom may be a chlorine atom or a bromine atom.

[0066] The conditions of the reaction and post-treatment carried out in step a2 can be appropriately set depending on the structures of compound x4 and compound x5, etc. For example, compound x4 and compound x5 can be reacted in a reaction mixture containing them to obtain compound (1).

[0067] X in formula (x5) 2 When is a hydroxy group, the reaction mixture may further contain an acid and / or a solvent as necessary. Examples of the acid include sulfuric acid, benzenesulfonic acid, p-toluenesulfonic acid monohydrate, and the like. Examples of the solvent include toluene, xylene, and the like. The reaction may be carried out while removing water generated by the condensation reaction. The temperature of the reaction mixture (reaction temperature) may be the reflux temperature of the solvent. The time (reaction time) for maintaining the reaction temperature may be, for example, 1 to 72 hours. The post-treatment may be carried out by a method including, for example, neutralizing the reaction mixture by adding an aqueous solution containing a base, dehydrating the organic layer containing compound (1), concentrating the organic layer after dehydration under reduced pressure to obtain a crude product, and purifying the crude product using a silica gel column or the like. The aqueous solution containing a base added during neutralization may be, for example, an aqueous solution of sodium hydrogen carbonate. The organic layer containing compound (1) may be dehydrated by using, for example, magnesium sulfate, or the like.

[0068] X in formula (x5) 2 When is a halogen atom, the reaction mixture may further contain at least one of a solvent, a base, and a catalyst, if necessary. As the solvent, base, and catalyst, various solvents, bases, and catalysts exemplified in the above step x can be used. The temperature of the reaction mixture (reaction temperature) may be, for example, -10 to 60°C. The time for which the reaction temperature is maintained (reaction time) may be, for example, 1 to 12 hours. The post-treatment may be performed, for example, by a method including washing compound (1), drying the washed compound (1) (for example, drying under reduced pressure), and purifying the crude product obtained after drying using a silica gel column or the like. The washing of compound (1) may be performed in the same manner as in step x.

[0069] In one embodiment, Z in compound (1) 1 -R a1 -OR a2 - (R a1 and R a2 is R in the above formula (x3) a1 and R in the above formula (x5)a2 are synonymous with R a1 and R a2 at least one of which is an alkylene group. In the case where the formula (1) is (a)-(a) or (b), the compound (1) can also be produced by a method including the above step a1 and the following step a3.

[0070] Step a3 is a step of reacting compound x4 with a compound (compound x6) represented by the following formula (x6) to obtain compound (1). [ka]

[0071] Here, A in the above formula (x6) 2 , Z 2 , R 2 , and n is A in the above formula (1). 2 , Z 2 , R 2 , and n are synonymous with R a2 is R in the above formula (x5) a2 is synonymous with X 3 represents a halogen atom. The halogen atom may be a chlorine atom or a bromine atom.

[0072] The conditions of the reaction and post-treatment carried out in step a3 can be appropriately set according to the structures of compound x4 and compound x6. For example, compound (1) can be obtained by reacting compound x4 and compound x6 in a reaction mixture containing them. The reaction mixture can further contain at least one of a solvent, a base, and a catalyst as necessary. As the solvent, base, and catalyst, various solvents, bases, and catalysts exemplified in the above step x can be used. The temperature of the reaction mixture (reaction temperature) can be, for example, 40 to 120° C. The time for which the reaction temperature is maintained (reaction time) can be, for example, 1 to 48 hours. The post-treatment can be carried out by a method including, for example, precipitating compound (1), washing the precipitated compound (1), drying the washed compound (1) (for example, 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 (1) can be carried out in the same manner as in step x.

[0073] In one embodiment, Z in compound (1) 1 -R b1 -COO-R b2 - (R b1 and R b2 each independently represents an alkylene group or a single bond.), compound (1) can also be produced by a method including the following steps b1 and b2.

[0074] Step b1 is a step of reacting compound x1 with a compound represented by the following formula (x7) (compound x7) to obtain a compound represented by the following formula (x8) (compound x8). [ka] [ka]

[0075] Here, A in the above formula 1 and R 1 is A in the above formula (1). 1and R 1 is synonymous with R b1 represents an alkylene group or a single bond; X 4 represents a hydroxy group or a halogen atom. The halogen atom may be a chlorine atom or a bromine atom.

[0076] The conditions of the reaction and post-treatment carried out in step b1 can be appropriately set according to the structures of compound x1 and compound x7. For example, compound x8 can be obtained by reacting compound x1 with compound x7 in a reaction mixture containing them. The reaction mixture can further contain at least one of a solvent, a base, and a catalyst as necessary. As the solvent, base, and catalyst, 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 180° C. The time for which the reaction temperature is maintained (reaction time) can be, for example, 1 to 120 hours. The post-treatment can be carried out, for example, by a method including precipitating compound x8, washing the precipitated compound x8, drying (e.g., drying under reduced pressure) compound x8 after washing, and purifying the crude product obtained after drying using a silica gel column, etc. Precipitation and washing of compound x8 can be carried out in the same manner as in step x.

[0077] Step b2 is a step of reacting compound x8 with a compound (compound x9) represented by the following formula (x9) to obtain compound (1). [ka]

[0078] Here, A in the above formula (x9) 2 , Z 2 , R 2 and n is A in the above formula (1). 2 , Z 2 , R 2 and n, R b2 represents an alkylene group or a single bond.

[0079] The conditions of the reaction and post-treatment carried out in step b2 can be appropriately set depending on the structures of compound x8 and compound x9, etc. For example, compound x8 and compound x9 can be reacted in a reaction mixture containing them under the same conditions as in step a2 to obtain compound (1).

[0080] <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 other than these components.

[0081] 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, based on 100 parts by mass of the total amount of liquid crystal components in the liquid crystal composition, from the viewpoints of light-shielding 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, based on 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, based on 100 parts by mass of the total amount of liquid crystal components in the liquid crystal composition.

[0082] The compound (1) may be contained in the liquid crystal composition as a dichroic dye. In other words, it can be said that the liquid crystal composition contains a dichroic dye containing the compound (1). The liquid crystal composition may contain a dichroic dye other than the compound (1). The number of types of dichroic dyes contained in the liquid crystal composition may be 1 to 6, 1 to 5, or 1 to 4. When a plurality of types of dichroic dyes are used, it is preferable that the plurality of 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 a red dye compound having a maximum absorption wavelength between 500 and 600 nm and a yellow dye compound having a maximum absorption wavelength between 400 and 500 nm, and it is preferable to further contain both the red dye compound and the yellow dye compound.

[0083] 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, based on 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 resistance 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, based on 100 parts by mass of the total amount of the liquid crystal components in the liquid crystal composition, from the viewpoints of the 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, based on 100 parts by mass of the total amount of the liquid crystal components in the liquid crystal composition.

[0084] (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). [ka]

[0085] In formula (2), R 11 is an alkyl group having 1 to 10 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 - may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -COO- or -OCO-; R 12 is 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 by a fluorine atom, and one -CH 2 - or two or more non-adjacent -CH 2 Each - may be independently replaced by -CH=CH-, -C≡C-, -O-, -CO-, -COO- or -OCO-; A 11 , A 12 and A13 are each independently (a3) 1,4-cyclohexylene group (one -CH 2 - or two or more non-adjacent -CH 2 - 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, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group (one -CH= or two or more non-adjacent -CH=s present in the naphthalene-2,6-diyl group and the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by -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; Z 11 and Z 12 are each independently a single bond, -CH 2 CH 2 -, -(CH 2 ) 4 -, -OCH 2 -, -CH 2 O-, -COO-, -OCO-, -OCF 2 -, -CF 2 represents O-, -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 11may be the same or different from each other.

[0086] 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, 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, more preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, still more preferably an alkyl group having 2 to 5 carbon atoms or an alkenyl group having 2 to 3 carbon atoms, and particularly preferably an alkyl group having 2 to 5 carbon atoms.

[0087] 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.

[0088] R 12 is preferably a fluorine atom, a cyano group, or an alkyl group having 1 to 5 carbon atoms (wherein one —CH 2 - or two or more non-adjacent -CH 2 - may be replaced by -O-.

[0089] A 11 , A 12 and A 13 Each 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): [ka]

[0090] R i3 , R i4 and R i5Each independently represents a hydrogen atom or a fluorine atom. 12 The wavy line represents the bond to Z. 12 Represents a bond to .

[0091] 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 It is preferable that A is aromatic. In order to improve the response speed, 11 and A 12 From these viewpoints, A is preferably aliphatic. 11 and A 12 each independently represents a trans-1,4-cyclohexylene group (one -CH 2 - or two or more non-adjacent -CH 2 - may be replaced by -O-, and -CH= in this group may be replaced by -N=), or preferably represents 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 (one -CH= or two or more non-adjacent -CH= in these groups may be replaced by -N=).

[0092] Among them, A 11 and A 12 More preferably, each independently represents any one of the following structures: [ka]

[0093] 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 part on the side.

[0094] A 11 and A 12More preferably, each independently represents any one of the following structures: In the following structures, the wavy line and * have the same meaning as above. [ka]

[0095] n 11 is preferably 0, 1 or 2. When emphasis is placed on improving Δε, n 11 is preferably 0 or 1. When the transition temperature (Tni) is important, n 11 is preferably 1 or 2.

[0096] The compound (2) may be used alone or in combination of two or more. For example, the compound (2) may be used in combination of two, three, four, five, six, seven, eight, or nine types, or in combination of ten or more types. There is no particular restriction on the type of compound that can be combined, but they are used in combination according to the desired performance such as solubility at low temperature, transition temperature, electrical reliability, and birefringence.

[0097] 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, the polymerizable compound, and the 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, the polymerizable compound, and the 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, the polymerizable compound, and the polymerization initiator in the liquid crystal composition.

[0098] 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 type liquid crystal compound).

[0099] In one embodiment, compound (2) may be represented by the formula (2): 12 It is preferable to use a compound in which R is a cyano group (hereinafter referred to as a "cyan liquid crystal compound").

[0100] In the cyan liquid crystal compound, Z in formula (2) 11 and Z 12 are each independently a single bond, -COO-, -OCO-, or -CH 2 -CH 2 - is preferable, and a single bond or -COO- is more preferable.

[0101] In the cyan liquid crystal compound, R 11 The number of carbon atoms is preferably 2 to 7, and more preferably 2 to 5.

[0102] In the cyan liquid crystal compound, n in formula (2) 11 is preferably 0 or 1.

[0103] Preferred specific examples of the cyan liquid crystal compound include compounds represented by the following formulas (vi-1) to (vi-11). [ka]

[0104] 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; 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.

[0105] More specific examples of the cyan liquid crystal compound include compounds represented by the following formulas (vi-A) to (vi-G). [ka]

[0106] 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.

[0107] More specific examples of the cyan liquid crystal compound include the compounds represented by the following formulas (2C-1) to (2C-18). [ka] [ka] [ka] [ka] [ka]

[0108] The above cyan liquid crystal compounds may be used alone or in combination of two or more.

[0109] 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. The content of the cyan liquid crystal compound 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.

[0110] In one embodiment, the above-mentioned cyan liquid crystal compound may be used in combination with a compound that does not fall under the category of a cyan liquid crystal compound. The compound that does not fall under the category of a cyan liquid crystal compound may be used alone or in combination of two or more.

[0111] 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 having 1 to 10 carbon atoms (including substituted ones), and Z in formula (2) 12 As specific examples of such compounds, it is preferable to use one or more of the compounds represented by the following formulae (2M-1) to (2M-3). [ka]

[0112] 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.

[0113] The liquid crystal component may contain a liquid crystal compound other than the compound (2). The content of the liquid crystal compound other than the compound (2) is preferably 10 mass % or less based on the total amount of the liquid crystal component in the liquid crystal composition.

[0114] The transition temperature (Tni) of the liquid crystal component (all liquid crystal compounds) 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) means 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 the nematic phase can be maintained even at high temperatures, and the wider the operating temperature range can be.

[0115] 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.

[0116] (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 is polymerized to form a polymer network that disperses the liquid crystal component. According to the liquid crystal composition, a polymer-dispersed type (polymer network type) liquid crystal can be formed by polymerizing the polymerizable compound. Therefore, the liquid crystal composition can be called a polymer-dispersed type (polymer network type) liquid crystal forming composition. In addition, 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) type liquid crystal material.

[0117] The polymerizable compound is a compound having a polymerizable group, and has radical polymerizability, cationic polymerizability, or anionic polymerizability. The polymerizable compound is preferably a (meth)acrylate. Here, "(meth)acrylate" means at least one of an acrylate and a corresponding methacrylate.

[0118] (Polymerization initiator) The polymerization initiator is used to polymerize the polymerizable compound. The polymerization initiator is preferably a photopolymerization initiator used when polymerization is performed by light irradiation. As the photopolymerization initiator, it is sufficient to use one that generates an active species corresponding to the polymerizability of the polymerizable compound, and for example, a photoradical polymerization initiator or a photocationic polymerization initiator can be used. As the photopolymerization initiator, a publicly known and commonly used one can be used.

[0119] (Additive ingredients) To the liquid crystal composition, a polymerization inhibitor, an antioxidant, a light stabilizer, a chain transfer agent, a pigment, a particle having a particle diameter of less than 1 μm, a chiral compound, or an alignment material can be added within a range that does not impair practical electro-optical properties and adhesion when a liquid crystal element is produced. Among these, it is preferable to use at least one selected from the group consisting of a polymerization inhibitor, an antioxidant, a light stabilizer, a particle having a particle diameter of less than 1 μm, and a pigment. As these additives, publicly known and commonly used ones can be used, and for example, the compounds described in International Publication No. 2022 / 138418 can be used in the same amount.

[0120] <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 above dichroic dye, a polymer network derived from the above polymerizable compound, and a liquid crystal component containing the above compound (2). The polymer network is composed of a polymer of the above polymerizable component (a polymer containing each of the polymerizable compounds exemplified as the polymerizable component as a monomer unit). The content of the above first to fourth components relative to the total amount of the polymerizable components in the liquid crystal composition can be read as the content of the monomer units derived from each component relative to the total amount (total mass) of the polymer in the liquid crystal layer. In addition, the content of the above polymerizable component relative to the total amount of the liquid crystal composition can be read as the content of the polymer relative to the total amount of the liquid crystal layer.

[0121] The liquid crystal layer contains a polymer network and a liquid crystal component, and can therefore be called a layer made of polymer-dispersed (polymer network) liquid crystal (polymer-dispersed liquid crystal layer). The 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 network structure of a polymer, a structure in which droplets of the liquid crystal component are dispersed in a polymer, or a structure in which both are mixed. The 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 the continuous phase of the liquid crystal component, or a structure in which both are mixed, but it is preferable that the layer has a structure in which a three-dimensional network structure of the polymer component is formed in the continuous phase of the liquid crystal component. 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, 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, so the liquid crystal layer can also be called a phase-separated liquid crystal layer.

[0122] The liquid crystal layer can be obtained, for example, by a method including coating a liquid crystal composition on a substrate. When the liquid crystal composition includes a polymerizable component, the method may further include polymerizing the polymerizable component after coating the liquid crystal component.

[0123] <Liquid crystal elements and light control elements> Another embodiment of the present invention is a liquid crystal element including at least a liquid crystal layer, an electrode, and a substrate supporting the liquid crystal layer and the electrode. Since the liquid crystal layer is the liquid crystal layer of the above embodiment (polymer dispersion type (polymer network type) liquid crystal layer), this liquid crystal element is a so-called polymer dispersion type (polymer network type) liquid crystal element.

[0124] The liquid crystal element can be in a light scattering state by the polymer network derived from the polymerizable compound and the liquid crystal molecules (liquid crystal components) present in the gaps therebetween when no voltage is applied. On the other hand, when a voltage is applied, the liquid crystal molecules are aligned perpendicularly to the substrate, so that the liquid crystal element can be in a light transmitting state. In this way, 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 is aligned together with the liquid crystal molecules when a voltage is applied, a color corresponding to the absorption wavelength of the dichroic dye can be expressed when no voltage is applied, and a light blocking state can be achieved when no voltage is applied by combining a plurality of dichroic dyes. For this reason, the liquid crystal element can be used as a liquid crystal light control element incorporated in a device that requires a light control function, or as a liquid crystal display element used in a display for displaying images.

[0125] The liquid crystal element is preferably used, for example, in building materials, light control glass, smart windows for vehicles, or light control 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, and the like. More specifically, the liquid crystal element can be used in products such as architectural light control elements such as windows, skylights, roofs, walls, partitions, partitions, and doors, transportation light control elements such as doors, windows, doors, helmets, and sunroofs, decorative light control elements such as sunglasses, glasses, sun visors, watches, mirrors, and reflectors, and display members such as flexible liquid crystal display elements, reflective liquid crystal display elements, transparent liquid crystal display elements, and variable diffusion films. EXAMPLES

[0126] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the compositions of the following examples and comparative examples, "parts" means "parts by mass".

[0127] <Example 1> (Synthesis of compound a-1) [ka] 1-Bromo-4-methylamino-anthracene-9,10-dione (10 g), potassium acetate (9.3 g), 2-(4-aminophenyl)ethanol (8.6 g), and xylene (20 mL) were reacted in a 200 mL eggplant flask at 120° C. for 4 hours. After the reaction solution was allowed to cool, methanol (20 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol and a 5 w / w% HCl aqueous solution in that order, and dried under reduced pressure to obtain a compound represented by the above formula (a-1) as compound a-1. The yield was 11.1 g, which was 95%.

[0128] (Synthesis of dichroic dye A) [ka] Compound a-1 (11.1 g), 4-butylbenzoic acid (6.5 g), p-toluenesulfonic acid monohydrate (600 mg), and toluene (150 mL) were added to a 100 mL eggplant flask equipped with a Dean-Stark apparatus, and the mixture was heated under reflux for 72 hours while removing water generated by condensation. The resulting reaction solution was washed four times with 1% aqueous sodium bicarbonate solution (100 mL) to extract the organic layer. The organic layer was dried over magnesium sulfate, and the solvent was distilled off 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 above formula (A) as dichroic dye A. The yield was 11.2 g, and the yield was 65%. The mass spectrum assignments of dichroic dye A are shown below. MS m / z: 532[M + ]

[0129] <Example 2> (Synthesis of compound a-2) [ka] 1-Bromo-4-methylamino-anthracene-9,10-dione (10 g), potassium acetate (9.3 g), 4-amino-m-cresol (4.3 g), and xylene (20 mL) were reacted in a 200 mL eggplant flask at 130° C. for 4 hours. After the reaction solution was allowed to cool, methanol (20 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol and a 5 w / w% HCl aqueous solution in that order, and dried under reduced pressure to obtain a compound represented by the above formula (a-2) as compound a-2. The yield was 10.2 g, which was 90%.

[0130] (Synthesis of dichroic dye B) [ka] Compound a-2 (10.2 g), triethylamine (4.5 g), and dichloromethane (100 mL) were added to a 100 mL eggplant flask equipped with a dropping funnel, and cooled to 5 ° C. in an ice water bath. Then, a solution of 3-(4-butylphenyl)propionyl chloride (6.5 g) dissolved in dichloromethane (15 mL) was slowly dropped. After the dropwise addition was completed, the reaction was allowed to proceed at room temperature for 2 hours. After the reaction was completed, the reaction solution was washed with 10% hydrochloric acid, pure water, and saturated saline, and the solvent was distilled off under reduced pressure. The obtained crude product was purified with a silica gel column (toluene / ethyl acetate = 20: 1) to obtain a compound represented by the above formula (B) as dichroic dye B. The yield was 13.2 g, and the yield was 85%. The mass spectrum assignment of dichroic dye B is shown below. MS m / z: 546[M + ]

[0131] <Example 3> (Synthesis of compound a-3) [ka] 1-Bromo-4-methylamino-anthracene-9,10-dione (10 g), potassium acetate (9.3 g), 3-amino-benzyl alcohol (4 g), and xylene (20 mL) were reacted in a 200 mL eggplant flask at 130° C. for 4 hours. After the reaction solution was allowed to cool, methanol (20 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol and a 5 w / w% HCl aqueous solution in that order, and dried under reduced pressure to obtain a compound represented by the above formula (a-3) as compound a-3. The yield was 10.4 g, which was 92%.

[0132] (Synthesis of dichroic dye C) [ka] Compound a-3 (10.4 g), triethylamine (5 g), and dichloromethane (100 mL) were added to a 100 mL eggplant flask equipped with a dropping funnel, and cooled to 5 ° C. in an ice water bath. Then, a solution of 3-(4-butylphenyl)propionyl chloride (7.0 g) dissolved in dichloromethane (15 mL) was slowly dropped. After the dropwise addition, the reaction was allowed to proceed at room temperature for 2 hours. After the reaction was completed, the reaction solution was washed with 10% hydrochloric acid, pure water, and saturated saline, and the solvent was distilled off under reduced pressure. The obtained crude product was purified with a silica gel column (toluene / ethyl acetate = 20: 1) to obtain a compound represented by the above formula (C) as dichroic dye C. The yield was 13.2 g, and the yield was 85%. The mass spectrum assignment of dichroic dye C is shown below. MS m / z: 518[M + ]

[0133] <Example 4> (Synthesis of compound a-4) [ka] 1-Bromo-4-methylamino-anthracene-9,10-dione (10 g), potassium acetate (9.3 g), 4-amino-phenol (3.3 g), and xylene (60 mL) were reacted in a 200 mL eggplant flask at 130° C. for 4 hours. After the reaction solution was allowed to cool, methanol (20 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol and a 5 w / w% HCl aqueous solution in that order, and dried under reduced pressure to obtain a compound represented by the above formula (a-4) as compound a-4. The yield was 9.7 g, which was 91%.

[0134] (Synthesis of dichroic dye D) [ka] Compound a-4 (9.7 g), 1-(3-bromopropyl)-4-butylbenzene (9.3 g), and N,N-dimethylformamide (100 mL) were added to a 200 mL eggplant flask equipped with a cooling tube, and the mixture was reacted at 90°C for 6 hours. After the reaction was completed, ethyl acetate was added to the reaction solution, which was washed with 10% hydrochloric acid, pure water, and saturated saline, and the solvent was distilled off under reduced pressure. The obtained crude product was purified using a silica gel column (toluene / ethyl acetate = 20:1) to obtain a compound represented by the above formula (D) as dichroic dye D. The yield was 13 g, and the yield was 83%. The mass spectrum of dichroic dye D is shown below. MS m / z: 518[M + ]

[0135] <Example 5> (Synthesis of dichroic dye E) [ka] 1-Bromo-4-methylamino-anthracene-9,10-dione (10 g), potassium acetate (9.3 g), 4-(4-isopentylphenethyl)aniline (10.7 g), and xylene (60 mL) were reacted in a 200 mL eggplant flask at 130° C. for 4 hours. After the reaction solution was allowed to cool, ethanol (40 mL) was added to precipitate a solid. The precipitated solid was collected by filtration, washed with methanol and 5 w / w% HCl aqueous solution in that order, and dried under reduced pressure to obtain a compound represented by the above formula (E) as dichroic dye E. The yield was 11.6 g, and the yield was 75%. The mass spectrum assignments of dichroic dye D are shown below. MS m / z: 502[M + ]

[0136] <Comparative Example 1> As the dichroic dye F, a compound represented by the following formula (F) was prepared. [ka]

[0137] <Comparative Example 2> As the dichroic dye G, a compound represented by the following formula (G) was prepared. [ka]

[0138] <Evaluation 1: Maximum absorption wavelength and dichroic ratio> The maximum absorption wavelengths and dichroic ratios of the dichroic dyes A to G obtained above were measured by the following method. The results are shown in Table 1.

[0139] (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 following structural formula means "% by mass"). Then, two 2 cm x 2 cm glass substrates with an ITO electrode layer, each having an ITO electrode layer and an alignment film for horizontal alignment on the ITO electrode layer, were prepared. The horizontal alignment film was made using AL1051 manufactured by JSR Corporation. Next, the two glass substrates with an ITO electrode layer were arranged so that the ITO electrode layer was on the inside of the cell, and a cell with an injection port was prepared. At this time, the cell thickness was adjusted to 3.5 μm by using plastic particles. A measurement sample was injected into the cell, and the injection port was sealed with a sealant to prepare a test panel (element) for testing. [Composition of Liquid Crystal Composition H] [ka]

[0140] (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 under conditions of 25°C and no applied voltage, thereby determining the maximum absorption wavelength of the dichroic dye.

[0141] (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 is parallel to the linearly polarized light, and the transmittance (A90) at the maximum absorption wavelength when the orientation direction is perpendicular to the linearly polarized light were measured. Using these transmittances, the dichroic ratio (R) was calculated according to the following formula. Dichroic ratio (R) = Transmittance (A0) / Transmittance (A90)

[0142] <Evaluation 2: Solubility> The solubilities of the dichroic dyes A to G obtained above were evaluated by the following method. The results are shown in Table 1.

[0143] Liquid crystal compositions were prepared containing 1% by mass of the dichroic dyes A to E obtained in the examples and the dichroic dyes F to G used as comparative examples in a liquid crystal composition H of 99% by mass. 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 covered with a built-in lid. This was stored in a temperature-controlled thermostatic chamber (manufactured by Espec Corp., SH-241) at 20°C for one week, and the occurrence of crystallization of the liquid crystal composition was visually confirmed every day. If no crystallization had occurred after one week, it was marked with ◯, and if crystallization had occurred after one week, it was marked with ×.

[0144] [Table 1]

Claims

1. The following formula (1) 【Chemistry 1】 [In formula (1), A １ and A ２ are each independently (a) 1,4-cyclohexylene group and 1,3-cyclohexylene group (one —CH 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 ３ - may be replaced.) (b) a 1,4-phenylene group and a 1,3-phenylene group (in which 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= in these groups may be replaced by -N=). and each of the hydrogen atoms present in the groups (a), (b), (c) and (d) may be independently 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; 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, 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 and R ２ each independently represents a hydrogen 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 ３ may be replaced by -, -O-, -S-, -CH=CH-, -CF=CF- or -C≡C-; R ３ is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkenyl group having 2 to 20 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. n represents an integer of 1 to 3; A ２ If there are multiple A's, ２ may be the same or different, Z ２ If there are multiple Z ２ may be the same or different, R ３ When there are multiple R ３ 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 following formula (1A) 【Chemistry 2】 [In formula (1A), A １ , A ２ , Z １ , Z ２ , R １ and R ２ has the same meaning as above.] The compound according to claim 1 ,

3. The above A １ and A ２ are each independently represented by the following formulae (a1), (b1) to (b12), and (d1) to (d4): 【Chemistry 3】 [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, A １ In the case of １ indicates the bond to A ２ In this case, the wavy line is Z １ indicates a bond to Z ２ indicates the bond to . The compound according to claim 1 or 2, wherein the R is a group selected from the group consisting of groups represented by the following formula:

4. The above A １ is the 1,4-phenylene group or the 1,3-phenylene group, ２ is the 1,4-cyclohexylene group, the 1,4-phenylene group, the naphthalene-2,6-diyl group, or the thiophene-2,5-diyl group.

5. The above A １ The compound according to claim 1 or 2, wherein

6. Said Z １ represents a single bond, -CH=CH-, or an alkylene group having 1 to 10 carbon atoms, and one or more -CH ２ The compound according to claim 1 or 2, wherein - may be substituted by -O-, -COO- or -OCO-.

7. The above A ２ is the 1,4-phenylene group, the naphthalene-2,6-diyl group, or the thiophene-2,5-diyl group, and Z １ Ga-CH ２ CH ２ -, -COO-, -CH=CH-, -OCH ２ CH ２ --, --OCH ２ CH ２ CH ２ --, --OCO-CH ２ --, --OCO-CH ２ CH ２ --, --CH ２ -COO-, -CH ２ -OCO-, -CH ２ CH ２ The compound according to claim 1 or 2, which is -OCO- or a single bond.

8. The R １ and the R ２ are each independently a linear or branched alkyl group having 1 to 30 carbon atoms.

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

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

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