Liquid crystal composition containing anthraquinone compound and light-control element

Abstract

To provide an anthraquinone compound useful as a dichroic dye for use in a liquid crystal composition and a light-control element, the compound being capable of achieving superior contrast.SOLUTION: A liquid crystal compound comprising two types of anthraquinone compounds.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a novel liquid crystal composition. [Background technology]

[0002] Various light-controlling films have been proposed to control the transmission of external light for purposes such as privacy protection in windows, doors, and partitions in vehicles such as trains and automobiles, and buildings such as business buildings and hospitals (Patent Documents 1 and 2). One such light-controlling film uses liquid crystal. Typically, liquid crystal light-controlling films can block visibility by controlling the transmission and scattering of light depending on whether or not a voltage is applied, but they cannot block light itself, which tends to increase glare due to light scattering. Therefore, attempts have been made to use dyes as materials for light-controlling panels to reduce glare and improve contrast (Patent Documents 3 and 4). When using such light-controlling panels in automotive windows, there is a growing demand for black elements that can block visible light for practical and aesthetic reasons. Such black light-controlling elements are strongly required to have high contrast with and without the application of voltage, to be close to achromatic both with and without the application of voltage, and to exhibit minimal color change during long-term outdoor use, i.e., when exposed to light at high temperatures for extended periods.

[0003] Dichroic dyes are generally used as dyes in liquid crystal light control films. Known light control elements that use liquid crystal compositions containing dichroic dyes include the GH (guest-host) system and the PDLC (polymer-dispersed liquid crystal) system, in which a composition of dye and liquid crystal is dispersed in a polymer. Various dichroic dyes have been proposed for each system (Patent Documents 4, 5, and 6).

[0004] Dichroic dyes commonly used in liquid crystal compositions for light-adjusting devices require not only a dichroic ratio to enhance contrast when used in a device, but also light resistance, UV resistance, heat resistance, and compatibility (solubility) of the dichroic dye with the components of the liquid crystal composition. Despite efforts to improve these properties, none of these have yet met market demands. For example, Patent Documents 4 and 7 disclose dichroic dye compositions suitable for light-adjusting applications. However, both exhibit significant hue changes upon prolonged exposure to light, and are not sufficiently lightfast for outdoor use. Furthermore, the dichroic dye described in Patent Document 7 has poor practicality due to its low dichroic ratio. Therefore, there is a strong demand for a light-adjusting device that achieves both of these properties. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 63-501512 [Patent Document 2] Japanese Patent Application Publication No. 03-47392 [Patent Document 3] Japanese Patent Application Publication No. 2018-205746 [Patent Document 4] Japanese Patent Application Laid-Open No. 2011-190314 [Patent Document 5] Japanese Patent Application Publication No. 62-5941 [Patent Document 6] WO2021 / 261181 [Patent Document 7] Special Publication No. 03-063589 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a liquid crystal composition that can provide a light-controlling device having a high dichroic ratio, an achromatic color, and excellent light resistance. [Means for solving the problem]

[0007] As a result of extensive research into solving the above problems, the present inventors have found that the above problems can be solved by using two types of dichroic dyes, and have thus completed the present invention.

[0008] Aspects or embodiments of the present invention may be summarized as follows. [1]. A liquid crystal composition containing (A) a dye compound and (B) a liquid crystal material, wherein the dye compound (A) (i) The following general formula (1) [ka] (In the formula, R1 represents a hydrogen atom, a linear or branched alkoxy group having 1 to 12 carbon atoms, a halogen atom, —CO2R8, —OCOR8, —COR8, a cyano group, or a trifluoromethyl group. R4, R5, R 6、 R7 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a halogen atom, -CO2R8, -OCOR8, -COR8, a cyano group, or a trifluoromethyl group. R2 and R3 each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, a linear or branched alkoxy group having 1 to 12 carbon atoms, or a group represented by the following formula (a): [ka] (In formula (a), R9 represents a hydrogen atom or a linear or branched alkyl group having 1 to 8 carbon atoms. When there are multiple R9s, they may be the same or different.) represents a substituent represented by R8 each independently represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a group represented by the following formula (b): [ka] (In formula (b), R 10 represents a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, or a linear or branched alkoxy group having 1 to 8 carbon atoms. 10When there are a plurality of groups, they may be the same or different.) or the following formula (c): [ka] (In formula (c), R 11 represents a hydrogen atom or a linear or branched alkyl group having 1 to 8 carbon atoms. 11 If there are multiple, they may be the same or different.) An anthraquinone compound represented by the formula: (ii) the following general formula (2) [ka] (In the formula, R 12 represents a hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. 13 represents a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, or a linear or branched alkoxy group having 1 to 8 carbon atoms. A liquid crystal composition comprising an anthraquinone compound represented by the formula: [2]. The liquid crystal composition according to [1], wherein the mass ratio of the anthraquinone compound represented by the general formula (1) to the anthraquinone compound represented by the general formula (2) is 2:1 to 1:2. [3]. The liquid crystal composition according to [1] or [2], wherein the concentration of the dye compound (A) contained in the liquid crystal composition relative to the liquid crystal material (B) is 0.5 to 10% by mass. [4]. The liquid crystal composition according to any one of [1] to [3], comprising an anthraquinone compound represented by the general formula (1) and a dichroic dye other than an anthraquinone compound represented by the general formula (2). [5]. A light-adjusting element comprising a pair of opposing substrates, at least one of which is a transparent substrate having a transparent electrode, and the liquid crystal composition according to any one of [1] to [4] sandwiched between the pair of substrates. [6]. The light-adjusting element according to [5] or [6], wherein both of the pair of substrates are transparent substrates having transparent electrodes. [Effects of the Invention]

[0009] By using the liquid crystal composition of the present invention, a light-controlling device having an achromatic color, high contrast and excellent light resistance can be obtained. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below. In the present invention, the term "lower limit value to upper limit value" means that both the lower limit value and the upper limit value are included. In this specification, the "anthraquinone compound" may be simply referred to as the "compound." Also, in this specification, in accordance with common chemical practice, "branched" hydrocarbyl substituents may include "cyclic" hydrocarbyl substituents (i.e., the residue obtained by removing one hydrogen atom from a cyclic hydrocarbyl group).

[0011] The liquid crystal composition of the present invention contains (A) a dye compound and (B) a liquid crystal material. The dye compound (A) contains both at least one anthraquinone compound represented by the following general formula (1) and at least one anthraquinone compound represented by the following general formula (2):

[0012] [ka]

[0013] In the anthraquinone compound represented by general formula (1), R1 represents a hydrogen atom, a linear or branched alkoxy group having 1 to 12 carbon atoms, a halogen atom, —CO2R8, —OCOR8, —COR8, a cyano group, or a trifluoromethyl group. R4, R5, R 6、R7 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a halogen atom, -CO2R8, -OCOR8, -COR8, a cyano group, or a trifluoromethyl group. R2 and R3 each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, a linear or branched alkoxy group having 1 to 12 carbon atoms, or a group represented by the following formula (a):

[0014] [ka]

[0015] (In formula (a), R9 represents a hydrogen atom or a linear or branched alkyl group having 1 to 8 carbon atoms. When there are multiple R9s, they may be the same or different.) represents a substituent represented by

[0016] R8 each independently represents a linear or branched alkyl group having 1 to 12 carbon atoms, or a group represented by the following formula (b):

[0017] [ka]

[0018] (In formula (b), R 10 represents a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, or a linear or branched alkoxy group having 1 to 8 carbon atoms. 10 When a plurality of groups are present, they may be the same or different.

[0019] [ka]

[0020] (In formula (c), R 11 represents a hydrogen atom or a linear or branched alkyl group having 1 to 8 carbon atoms. 11When a plurality of groups are present, they may be the same or different. represents a substituent represented by the formula:

[0021] [ka]

[0022] (In the anthraquinone compound represented by the general formula (2), R 12 represents a hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. 13 represents a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, or a linear or branched alkoxy group having 1 to 8 carbon atoms.

[0023] Specific examples of the linear or branched alkoxy group having 1 to 12 carbon atoms represented by R1 in general formula (1) include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an iso-propoxy group, an n-butoxy group, an iso-butoxy group, a sec-butoxy group, a t-butoxy group, an n-pentyloxy group, an iso-pentyloxy group, a neo-pentyloxy group, a t-pentyloxy group, a hexyloxy group, a heptyloxy group, and an octyloxy group. A linear or branched alkoxy group having 1 to 4 carbon atoms is preferred, and a linear alkoxy group having 1 to 4 carbon atoms is more preferred.

[0024] In the general formula (1), examples of the halogen atom that can be represented by R1 and R4 to R7 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred.

[0025] Specific examples of R1 in the general formula (1) include a hydrogen atom, a linear or branched alkoxy group having 1 to 12 carbon atoms, a halogen atom, -COR, -OCOR, -COR, a cyano group, or a trifluoromethyl group, with an alkoxy group, a halogen atom, -COR, a cyano group, or a trifluoromethyl group being preferred, and a linear or branched alkoxy group, a halogen atom, or -COR being more preferred.

[0026] Specific examples of the linear or branched alkyl group having 1 to 4 carbon atoms represented by R4 to R7 in the general formula (1) include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an isopropyl group, an isobutyl group, a sec-butyl group, and a t-butyl group, and an isobutyl group, a sec-butyl group, and a t-butyl group are preferred.

[0027] In the general formula (1), examples of the linear or branched alkoxy group having 1 to 4 carbon atoms represented by R4 to R7 include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an iso-propoxy group, an n-butoxy group, an iso-butoxy group, a sec-butoxy group, and a t-butoxy group.

[0028] Specific examples of R4 to R7 in general formula (1) include, independently of one another, a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a halogen atom, —COR, —COR, —COR, a cyano group, or a trifluoromethyl group, of which a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, —COR, a cyano group, or a trifluoromethyl group is preferred, and a hydrogen atom, an alkyl group, a halogen atom, —COR, or a cyano group is more preferred.

[0029] Among the linear or branched alkyl groups having 1 to 12 carbon atoms represented by R8 in general formula (1), specific examples of linear groups include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, and an n-dodecyl group. Of these, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group are preferred, and a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group are more preferred. Specific examples of the branched chain include an isopropyl group, an isobutyl group, a sec-butyl group, a t-butyl group, an isopentyl group, an isohexyl group, a t-pentyl group, a 2-methylpentyl group, a 2-methylhexyl group, a 2-methylheptyl group, a 3-methylbutyl group, a 3-methylpentyl group, a 3-methylhexyl group, a 3-methylheptyl group, a 2-ethylpropyl group, a 2-ethylbutyl group, a 2-ethylhexyl group, a 2-propylhexyl group, a 2-butylhexyl group, a 2-pentylhexyl group, and a 2-pentylheptyl group, and an isobutyl group, a sec-butyl group, and a t-butyl group are preferred.

[0030] Among the linear or branched alkyl groups having 1 to 12 carbon atoms represented by R2 and R3 in general formula (1), specific examples of the linear alkyl groups include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, and an n-dodecyl group. Of these, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, and an n-heptyl group are preferred, an n-butyl group, an n-pentyl group, an n-hexyl group, and an n-heptyl group are more preferred, and an n-butyl group and an n-heptyl group are particularly preferred. Specific examples of the branched chain include an isopropyl group, an isobutyl group, a sec-butyl group, a t-butyl group, an isopentyl group, an isohexyl group, a t-pentyl group, a 2-methylpentyl group, a 2-methylhexyl group, a 2-methylheptyl group, a 3-methylbutyl group, a 3-methylpentyl group, a 3-methylhexyl group, a 3-methylheptyl group, a 2-ethylpropyl group, a 2-ethylbutyl group, a 2-ethylhexyl group, a 2-propylhexyl group, a 2-butylhexyl group, a 2-pentylhexyl group, and a 2-pentylheptyl group, and an isobutyl group, a sec-butyl group, and a t-butyl group are preferred.

[0031] Specific examples of the linear or branched alkoxy group having 1 to 12 carbon atoms represented by R2 and R3 in general formula (1) include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an iso-propoxy group, an n-butoxy group, an iso-butoxy group, a sec-butoxy group, a t-butoxy group, an n-pentyloxy group, an iso-pentyloxy group, a neo-pentyloxy group, a t-pentyloxy group, a hexyloxy group, a heptyloxy group, and an octyloxy group. A linear or branched alkoxy group having 1 to 7 carbon atoms is preferred, and a linear alkoxy group having 1 to 7 carbon atoms is more preferred.

[0032] In the formulas (a) to (c), R9 to R 11Among the linear or branched alkyl groups having 1 to 8 carbon atoms represented by the formula (I), specific examples of the linear group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, and an n-octyl group. Of these, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, and an n-heptyl group are preferred, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group are more preferred, and an n-propyl group, an n-butyl group, and an n-pentyl group are particularly preferred. Specific examples of the branched chain include an isopropyl group, an isobutyl group, a sec-butyl group, a t-butyl group, an isopentyl group, an isohexyl group, a t-pentyl group, a 2-methylpentyl group, a 2-methylhexyl group, a 2-methylheptyl group, a 3-methylbutyl group, a 3-methylpentyl group, a 3-methylhexyl group, a 3-methylheptyl group, a 2-ethylpropyl group, a 2-ethylbutyl group, and a 2-ethylhexyl group, and an isobutyl group, a sec-butyl group, and a t-butyl group are preferred.

[0033] In the formula (b), R 10 Specific examples of the linear or branched alkoxy group having 1 to 8 carbon atoms represented by the formula (I) include a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, an iso-butoxy group, a sec-butoxy group, a t-butoxy group, an n-pentyloxy group, an iso-pentyloxy group, a neo-pentyloxy group, a t-pentyloxy group, a hexyloxy group, a heptyloxy group, and an octyloxy group. A linear or branched alkoxy group having 1 to 4 carbon atoms is preferred, and a linear alkoxy group having 1 to 4 carbon atoms is more preferred.

[0034] The compound represented by the above formula (1) can be synthesized by a conventionally known method described in, for example, JP-A-62-5941, JP-A-2017-518413, JP-A-58-196260, etc.

[0035] Specific preferred examples of the compound represented by the general formula (1) include the following, but the present invention is not limited to these.

[0036] [ka] TIFF2025133092000012.tif91170

[0037] In the general formula (2), R 12 The alkyl group having 1 to 12 carbon atoms represented by may be either a straight chain or a branched chain. Specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an isopentyl group, a neo-pentyl group, a t-pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a 2-ethylhexyl group, a 2-propylhexyl group, a 2-butylhexyl group, a 2-pentylhexyl group, and a 2-pentylheptyl group. 12 When R is a linear alkyl group, it preferably has 4 to 10 carbon atoms, more preferably 7 to 10 carbon atoms. 12 When is a branched alkyl group, it preferably has 3 to 6 carbon atoms, and more preferably 3 or 4 carbon atoms.

[0038] R in Equation (2) 12 The alkoxy group having 1 to 12 carbon atoms represented by may be either a straight chain or a branched chain. Specific examples thereof include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an iso-propoxy group, an n-butoxy group, an iso-butoxy group, a sec-butoxy group, a t-butoxy group, an n-pentyloxy group, an iso-pentyloxy group, a neo-pentyloxy group, a t-pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, a dodecyloxy group, a 2-ethylhexyloxy group, a 2-propylhexyloxy group, a 2-butylhexyloxy group, a 2-pentylhexyloxy group, and a 2-pentylheptyloxy group. A linear or branched alkoxy group having 1 to 8 carbon atoms is preferred, a linear or branched alkoxy group having 5 to 8 carbon atoms is more preferred, and a linear alkoxy group having 5 to 8 carbon atoms is even more preferred.

[0039] R in Equation (2) 12 As the alkyl group, a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 6 carbon atoms, or a linear or branched alkoxy group having 1 to 8 carbon atoms is preferred, a linear alkyl group having 4 to 10 carbon atoms, a branched alkyl group having 3 or 4 carbon atoms, or a linear or branched alkoxy group having 5 to 8 carbon atoms is more preferred, and a linear alkyl group having 7 to 10 carbon atoms or a linear alkoxy group having 5 to 8 carbon atoms is even more preferred.

[0040] In the general formula (2), R 13 The alkyl group having 1 to 8 carbon atoms represented by may be either a straight chain or a branched chain. Specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an isopentyl group, a neo-pentyl group, a t-pentyl group, a hexyl group, a heptyl group, an octyl group, and a 2-ethylhexyl group. A straight chain or branched chain alkyl group having 1 to 4 carbon atoms is preferred, and a branched chain alkyl group having 3 or 4 carbon atoms is more preferred.

[0041] R in Equation (2) 13 The alkoxy group having 1 to 8 carbon atoms represented by may be either linear or branched. Specific examples thereof include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an iso-propoxy group, an n-butoxy group, an iso-butoxy group, a sec-butoxy group, a t-butoxy group, an n-pentyloxy group, an iso-pentyloxy group, a neo-pentyloxy group, a t-pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, and a 2-ethylhexyloxy group, and a linear alkoxy group having 1 to 4 carbon atoms is more preferred.

[0042] R in Equation (2) 13 As the alkyl group, a linear or branched alkyl group having 1 to 8 carbon atoms is preferable, a linear or branched alkyl group having 1 to 4 carbon atoms is more preferable, and a branched alkyl group having 3 or 4 carbon atoms is even more preferable.

[0043] Specific preferred examples of the compound represented by the general formula (2) include the following, but the present invention is not limited to these.

[0044] [ka]

[0045] The anthraquinone compound represented by general formula (1) can be synthesized, for example, based on the method described in US Patent Application Publication No. 2004 / 087692. More specifically, the anthraquinone compound represented by general formula (1) can be synthesized by reacting an anthraquinone compound represented by the following formula (m), which has been synthesized by a conventional method as described in, for example, JP-A-63-72760, with an iodobenzene derivative represented by the following formula (n), in a solvent such as N-methyl-2-pyrrolidone, at 140 to 160° C. under basic conditions such as potassium carbonate, in the presence of a copper catalyst such as copper powder. The compound represented by the general formula (1-1) according to the modified embodiment described below can also be synthesized in a similar manner.

[0046] [ka]

[0047] In some modified embodiments, part or all of the anthraquinone compound represented by general formula (1) may be replaced with a compound represented by the following general formula (1-1): General formula (1-1) is a compound represented by the following general formula (1) in which R, R 4、 This corresponds to the case where any of the hydrogen atoms, linear alkoxy groups having 1 to 12 carbon atoms or branched alkoxy groups having 3 to 12 carbon atoms, halogen atoms, —COR, —OCOR, —COR, cyano groups, or trifluoromethyl groups of R5, R6, and R7 is replaced with a linear alkyl group having 1 to 12 carbon atoms or a branched alkyl group having 3 to 12 carbon atoms.

[0048] [ka]

[0049] In formula (1-1), R1 represents a hydrogen atom, a linear alkyl group having 1 to 12 carbon atoms, a branched alkyl group having 3 to 12 carbon atoms, a linear alkoxy group having 1 to 12 carbon atoms, a branched alkoxy group having 3 to 12 carbon atoms, a halogen atom, -CO2R8, -OCOR8, -COR8, a cyano group, or a trifluoromethyl group. 6、 R7 each independently represent a hydrogen atom, a linear alkyl group having 1 to 12 carbon atoms or a branched alkyl group having 3 to 12 carbon atoms, a linear alkoxy group having 1 to 12 carbon atoms or a branched alkoxy group having 3 to 12 carbon atoms, a halogen atom, -CO2R8, -OCOR8, -COR8, a cyano group, or a trifluoromethyl group. R2 and R3 each independently represent a hydrogen atom, a linear alkyl group having 1 to 12 carbon atoms or a branched alkyl group having 3 to 12 carbon atoms, a linear alkoxy group having 1 to 12 carbon atoms or a branched alkoxy group having 3 to 12 carbon atoms, or a group represented by the following formula (a):

[0050] [ka]

[0051] (In formula (a), R9 represents a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, or a branched alkyl group having 3 to 8 carbon atoms. When there are multiple R9s, they may be the same or different.) represents a substituent represented by the formula: R8 each independently represents a linear alkyl group having 1 to 12 carbon atoms or a branched alkyl group having 3 to 12 carbon atoms,

[0052] [ka]

[0053] (In formula (b), R 10represents a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, or a linear alkoxy group having 1 to 8 carbon atoms or a branched alkoxy group having 3 to 8 carbon atoms. 10 When a plurality of groups are present, they may be the same or different. [ka]

[0054] (In formula (c), R 11 represents a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, or a branched alkyl group having 3 to 8 carbon atoms. 11 When a plurality of are present, they may be the same or different.

[0055] In some embodiments, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 The possible and preferred options that fit the definition of may be those described above for general formula (1). In another embodiment, in the compound of the above general formula (1-1), R1 is preferably a linear alkyl group or a branched alkyl group having 4 to 12 carbon atoms; R2 and R3 are each independently preferably a linear alkoxy group having 1 to 12 carbon atoms or a branched alkoxy group having 3 to 12 carbon atoms, more preferably a linear alkoxy group or a branched alkoxy group having 4 to 12 carbon atoms;It is preferred that at least one of R4, R5, R6, and R7 is a cyano group, and the remaining R4, R5, R6, and R7 are a hydrogen atom, a linear alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 to 4 carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms or a branched alkoxy group having 3 to 4 carbon atoms, a halogen atom, —CO2R8, —OCOR8, —COR8, or a trifluoromethyl group, and it is preferred that at least one of R4 and R5 is a cyano group, and the remaining R4, R5, R6, and R7 are a hydrogen atom, a linear alkyl group having 1 to 4 carbon atoms or a branched alkoxy group having 3 to 4 carbon atoms, a halogen atom, —CO2R8, —OCOR8, —COR8, or a trifluoromethyl group. R4, R5, R6, and R7 are more preferably a hydrogen atom, a linear alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 to 4 carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms or a branched alkoxy group having 3 to 4 carbon atoms, a halogen atom, —CO2R8, —OCOR8, —COR8, or a trifluoromethyl group, and one of R4 and R5 is a cyano group, and the remaining R4, R5, R6, and R7 are each a hydrogen atom, a linear alkyl group having 1 to 4 carbon atoms, or It is even more preferred that R4 and R5 are a branched alkyl group having 3 to 4 carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms, a branched alkoxy group having 3 to 4 carbon atoms, a halogen atom, —CO2R8, —OCOR8, —COR8, or a trifluoromethyl group, and one of R4 and R5 is a cyano group located at the ortho position relative to the cyano group (—CN) shown in the general formula above, and the remaining R4, R5, R6, and R7 are a hydrogen atom, a linear alkyl group having 1 to 4 carbon atoms, or It is even more preferable that it is a branched alkyl group having 3 to 4 carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms, a branched alkoxy group having 3 to 4 carbon atoms, a halogen atom, —COR, —OCOR, —COR, or a trifluoromethyl group, and it is even more preferable that one of R and R is a cyano group located in the ortho position relative to the cyano group (—CN) shown in the general formula above, and the other R, R, R, and R are all hydrogen atoms.

[0056] Suitable specific examples of the compound represented by general formula (1-1) include, but are not limited to, the following.

[0057] [ka]

[0058] The mass ratio of the anthraquinone compounds represented by the general formula (1) and the general formula (2) is not particularly limited, but is usually 10:1 to 1:10, preferably 5:1 to 1:5, and particularly preferably 2:1 to 1:2.

[0059] The content of the anthraquinone compounds represented by the general formulas (1) and (2) in the liquid crystal composition is not particularly limited, but is usually 0.5 to 10 parts by mass, preferably 1 to 8 parts by mass, and more preferably 3 to 8 parts by mass, relative to 100 parts by mass of the liquid crystal material. In the present invention, when a dichroic dye (described below) other than the compounds represented by the general formulas (1) and (2) is used in combination, it is preferable that the total content of the dye compound (A) and the dichroic dye other than the dye compound (A) be in the above range.

[0060] The combination of the anthraquinone compounds represented by the general formula (1) and the general formula (2) is not particularly limited, but a combination of an anthraquinone compound represented by the general formula (1) in which R1 is an alkyl group having 4 to 8 carbon atoms (Nos. 1, 3, 4, 12, 14, and 15) and an anthraquinone compound represented by the general formula (2) in which R5 is an alkyl group having 4 to 10 carbon atoms (Nos. 101, 102, and 105) is preferred.

[0061] The liquid crystal material contained in the composition of the present invention is not particularly limited as long as it is a material (a compound having liquid crystal properties) having liquid crystal properties such as nematic liquid crystal, cholesteric liquid crystal, smectic liquid crystal, etc. Examples of the compound having liquid crystal properties include the liquid crystal compounds described in pages 154 to 192 and 715 to 722 of "Liquid Crystal Device Handbook" (edited by the 142nd Committee of the Japan Society for the Promotion of Science, Nikkan Kogyo Shimbun, 1989), specifically, Schiff base type, azoxy type, biphenyl type, phenylcyclohexane type, ester type, terphenyl type, biphenylcyclohexane type, pyrimidine type, dioxane type, bicyclooctane type, cubane type, etc.

[0062] The liquid crystal composition of the present invention may contain an optically active substance that exhibits or does not exhibit a liquid crystal phase, such as a dichroic dye other than the anthraquinone compounds represented by the general formula (1) or the general formula (2), or cholesteryl noenoate, various additives such as an ultraviolet absorber and an antioxidant, a photocurable compound, a photopolymerization initiator, etc.

[0063] In order to adjust the performance of the light-controlling element, such as contrast, light resistance, and hue, a dichroic dye other than the compounds represented by the general formula (1) and the general formula (2) may be used in combination with the composition of the present invention. The dichroic dye that can be used in combination is not particularly limited, and may be selected from, for example, azo dyes, anthraquinone dyes, perylene dyes, quinophthalone dyes, merocyanine dyes, azomethine dyes, phthaloperylene dyes, indigo dyes, azulene dyes, dioxazine dyes, polythiophene dyes, and the like. Specific examples include those described in "Dichroic dyes for Liquid Crystal Display" (AVI Vashchenko, CRC, 1994). Among these, it is preferable to use an azo dye, an anthraquinone dye, a perylene dye, or a quinophthalone dye in combination, it is more preferable to use an azo dye or an anthraquinone dye in combination, and it is even more preferable to use an anthraquinone dye in combination.

[0064] Suitable specific examples of dichroic dyes other than the anthraquinone compounds represented by general formula (1) and the anthraquinone compounds represented by general formula (2) include, but are not limited to, compounds (anthraquinone dyes) represented by the following general formulas (3-1) to (3-3).

[0065] [ka]

[0066] R in formula (3-1) 15 is not particularly limited, but may be a linear or branched alkyl group having 4 to 7 carbon atoms or a substituent represented by the following formula (d):

[0067] [ka]

[0068] (In formula (d), R 21 represents a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, or a branched alkyl group having 3 to 8 carbon atoms. is preferred.

[0069] R in formula (3-2) 16 and R 17 are not particularly limited, but are preferably each independently a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms, a linear or branched alkoxy group having 4 to 8 carbon atoms (which may be interrupted by an aryl ring), a linear or branched fatty acid ester group having 6 to 18 carbon atoms, or a substituent represented by the above formula (d).

[0070] R in formula (3-3) 18 is not particularly limited, but is preferably a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, or a branched alkyl group having 3 to 8 carbon atoms.

[0071] R 19 and R 20 are not particularly limited, but each independently represents a hydrogen atom or the following formula (e):

[0072] [ka]

[0073] (In formula (e), R 22 represents a linear alkyl group having 1 to 8 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms, a linear alkoxy group having 1 to 8 carbon atoms, or a branched alkoxy group having 3 to 8 carbon atoms. A substituent represented by the following formula is preferred. R 19 and R 20It is more preferable that one of the above is a hydrogen atom and the other is a substituent represented by the above formula (e).

[0074] Suitable, non-limiting examples of anthraquinone dyes that can be used as dichroic dyes other than the anthraquinone compounds represented by general formula (1) and the anthraquinone compounds represented by general formula (2) are shown in Tables 1 to 4 below.

[0075] [Table 1]

[0076] [Table 2]

[0077] [Table 3]

[0078] [Table 4]

[0079] Suitable, non-limiting examples of azo dyes used as dichroic dyes other than the anthraquinone compounds represented by general formula (1) and the anthraquinone compounds represented by general formula (2) include compounds represented by the following general formula (4).

[0080] [ka]

[0081] A1 is not particularly limited, but may be a hydrogen atom, -CO2A3, a linear or branched alkyl group having 4 to 8 carbon atoms, or a substituent represented by the following formula (f), (g), or (h):

[0082] [ka]

[0083] (In formula (f), A4 represents a linear alkoxy group having 1 to 8 carbon atoms or a branched alkoxy group having 3 to 8 carbon atoms. Also, in formulas (g) and (h), A5 represents a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms.) is preferred. Furthermore, A3 in formula (4) is preferably a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms.

[0084] A2 is not particularly limited, but may be a substituent represented by the following formula (i), (j) or (k):

[0085] [ka]

[0086] (In formula (i), A6 represents a linear alkyl group having 1 to 8 carbon atoms. In formulas (j) and (k), A7 and A8 each independently represent a 1,4-phenylene group or a 1,4-naphthalenediyl group, A9 represents a linear alkoxy group having 1 to 8 carbon atoms, L1 represents -N=N- or -N=CH-, and L2 represents -O- or -O-CO-.) is preferred.

[0087] Suitable, non-limiting specific examples of azo dyes that can be used as dye compounds other than the anthraquinone compounds represented by general formula (1) and the anthraquinone compounds represented by general formula (2) are shown in Tables 6 and 7.

[0088] [Table 5]

[0089] [Table 6]

[0090] When a dichroic dye other than the anthraquinone compound represented by the general formula (1) and the compound represented by the general formula (2) is used in combination, the content of the compounds represented by the general formula (1) and the general formula (2) in the total dichroic dye is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more.

[0091] The combination of the anthraquinone compounds represented by the general formula (1), the general formula (2), the general formula (3-1), the general formula (3-2), and the general formula (3-3) is not particularly limited, but a preferred combination is an anthraquinone compound represented by the general formula (1) in which R1 is an alkyl group having 4 to 8 carbon atoms (Nos. 1, 3, 4, 12, 14, and 15), an anthraquinone compound represented by the general formula (2) in which R5 is an alkyl group having 4 to 10 carbon atoms (Nos. 101 and 102), an anthraquinone compound represented by the general formula (3-1) No. 202, and an anthraquinone compound represented by the general formula (3-2) Nos. 213, 215, and 220.

[0092] The liquid crystal composition may further contain light stabilizers such as benzotriazoles, benzophenones, and hindered amines, antioxidants such as phosphites and hindered phenols, thermal polymerization inhibitors, thiol compounds, photosensitizers, photosensitizers, chain transfer inhibitors, polymerization inhibitors, adhesion promoters, antifoaming agents, crosslinking agents, surfactants, thermosetting accelerators, thermoplastic resins, thermosetting resins, thickeners such as urethane diacrylate, etc. Furthermore, spherical or cylindrical spacers made of silica, glass, plastic, ceramic, etc. may be added to control the cell gap as a light-controlling element. In this case, the cell gap can be set in the range of 2 to 100 μm.

[0093] For example, a photocurable compound and a photopolymerization initiator can be added to a liquid crystal composition, as exemplified in Patent Document 4. By photocuring a liquid crystal composition containing these components, the polymer and the liquid crystal substance are phase-separated, and a film having a light-controlling layer can be obtained.

[0094] In this case, the photocurable compound having a functional group polymerizable by the action of a photopolymerization initiator is not particularly limited, but examples thereof include compounds having a (meth)acrylate group, compounds having a vinyl group, and compounds having an allyl group. Compounds having a (meth)acrylate group are preferred. The photocurable compound may be used alone or as a mixture of two or more. It is more preferred to use both a mono(meth)acrylate compound having one (meth)acrylate group in one molecule and a di(meth)acrylate compound having two (meth)acrylate groups in one molecule in combination. In this specification, the term "(meth)acrylate" means "methacrylate and / or acrylate."

[0095] The mono(meth)acrylate compound is preferably a mono(meth)acrylate having a linear or branched alkyl group having 5 to 13 carbon atoms, and specific examples thereof include linear alkyl mono(meth)acrylates such as pentyl(meth)acrylate, hexyl(meth)acrylate, heptyl(meth)acrylate, octyl(meth)acrylate, nonyl(meth)acrylate, decyl(meth)acrylate, undecyl(meth)acrylate, dodecyl(meth)acrylate, and tridecyl(meth)acrylate, and branched alkyl mono(meth)acrylates such as 2-methylhexyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, 2-propylhexyl(meth)acrylate, 2-methylheptyl(meth)acrylate, 2-ethylheptyl(meth)acrylate, and 2-propylheptyl(meth)acrylate.

[0096] Suitable examples of the di(meth)acrylate compound include 1,4-butanediol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,7-heptanediol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,11-undecanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, and 1,13-tridecanediol di(meth)acrylate.

[0097] The photopolymerization initiator that can be contained in the liquid crystal composition is not particularly limited as long as it is a compound that can polymerize a photocurable compound by irradiation with light. As the photopolymerization initiator, one that remains in the cured liquid crystal composition after irradiation with light and does not cause deterioration of the dichroic dye, etc. is preferred. The photopolymerization initiator may be used alone or as a mixture of two or more types. As the photopolymerization initiator, for example, alkylphenone-based photopolymerization initiators such as Darocur 1173, Irgacure 651, and Irgacure 184, and phosphine oxide-based photopolymerization initiators such as Irgacure TPO are preferably used.

[0098] The light-adjusting element comprises a pair of substrates, at least one of which is a transparent substrate having a transparent electrode, and a layer of the liquid crystal composition according to any of the above embodiments or a photocured product thereof sandwiched between them. Examples of the substrate include inorganic transparent materials such as glass and quartz, and colorless, transparent, or opaque materials such as metals, metal oxides, semiconductors, ceramics, and plastic plates and films. The electrodes are formed on the substrate by applying a thin film of, for example, a metal oxide, metal, semiconductor, or organic conductive material to the entire surface or a portion of the substrate using a known coating method, printing method, or vapor deposition method such as sputtering. To obtain a particularly large-area light-adjusting element, it is desirable to use an electrode substrate in which an ITO (indium oxide, tin oxide) electrode is formed on a transparent polymer film such as PET using a vapor deposition method such as sputtering or a printing method, from the standpoints of productivity and processability. Wiring may be provided on the substrate to connect the electrodes or the electrodes to the outside. For example, the substrate may be a segment-drive electrode substrate, a matrix-drive electrode substrate, or an active-matrix drive electrode substrate. Furthermore, the electrode surface provided on the substrate may be covered entirely or partially with a protective film or alignment film made of organic compounds such as polyimide, polyamide, silicon, and cyanide compounds, inorganic compounds such as SiO2, TiO2, and ZrO2, or mixtures thereof.

[0099] The use of a plastic film as a substrate allows for a flexible and lightweight light-control device. Therefore, the light-control device can be sandwiched between a pair of flat or curved glass or hard plastic substrates via an adhesive layer such as polyvinyl butyral, vinyl acetate ester, double-sided tape, or adhesive. Alternatively, the light-control device can be attached to the surface of a single flat or curved glass or hard plastic substrate using double-sided tape or adhesive. The light-control device can also be sandwiched between soft plastic substrates or attached to one or both sides. A protective layer such as a hard coat, an ultraviolet-blocking layer, an infrared-blocking layer, or a half mirror may be provided on the substrate surface opposite the electrode surface of the light-control device, or a color filter or polarizer filter may be laminated thereon. Furthermore, the light-control device may be laminated as an electroluminescent display device, a light-emitting diode display device, an electrochromic display device, or another liquid crystal display device.

[0100] The driving device for applying voltage to the dimming element is a device that can apply DC or AC voltage and that opens or shorts the electrodes when no voltage is applied. This driving device may also be equipped with a voltage application circuit for segment driving, a voltage application circuit for matrix driving, a voltage application circuit for active matrix driving, etc.

[0101] Such a light-adjusting element has a neutral color, little color leakage in the visible light range, and excellent contrast, and is therefore ideal for use in vehicles or as a building material. [Example]

[0102] The present invention will be described in more detail below with reference to examples, but these are illustrative and do not limit the present invention in any way. In the text, "parts" and "%" are by mass unless otherwise specified. The maximum absorption wavelength in the examples is a value measured using a spectrophotometer "UV-3150 manufactured by Shimadzu Corporation."

[0103] Examples using compounds represented by general formula (1) Synthesis Example 1 (Synthesis of the anthraquinone compound represented by No. 1 in the above specific example) To 20 parts of NMP, 0.9 parts of the compound represented by the following formula (5A), 0.02 parts of copper powder, 0.02 parts of copper iodide, 2.0 parts of 1-fluoro-4-iodobenzene, 0.02 parts of potassium carbonate, and 0.15 parts of sodium acetate were added and stirred at 140-150°C for 12 hours. The reaction solution was then cooled to 25°C, and 200 parts of methanol was added. The mixture was further stirred for 1 hour. The reaction product was collected by filtration, washed with methanol, and then dried in a hot air oven at 50°C for 24 hours. The resulting crude product was dissolved in toluene and purified using a column chromatography column with toluene as the developing solvent. The solvent was removed from the purified solution by vacuum distillation, and the mixture was dried in a hot air oven at 50°C for 24 hours to obtain 0.2 parts of the above compound represented by No. 1 as a dark brown solid. The maximum absorption wavelength of this compound in toluene was 651 nm.

[0104] [ka]

[0105] Synthesis Example 2 (Synthesis of anthraquinone compound represented by No. 12 of the above specific example) To 20 parts of NMP, 0.9 parts of the compound represented by formula (5A), 0.02 parts of copper powder, 0.02 parts of copper iodide, 2.0 parts of 4-butoxy-1-iodobenzene, 0.02 parts of potassium carbonate, and 0.15 parts of sodium acetate were added and stirred at 140-150°C for 12 hours. The reaction solution was then cooled to 25°C, and 200 parts of methanol was added. The mixture was further stirred for 1 hour. The reaction product was collected by filtration, washed with methanol, and then dried in a hot air oven at 50°C for 24 hours. The resulting crude product was dissolved in toluene and purified using a column chromatography column with toluene as the developing solvent. The solvent was removed from the purified solution by vacuum distillation, and the mixture was dried in a hot air oven at 50°C for 24 hours to obtain 0.2 parts of the above compound represented by formula (5A) as a dark brown solid. The maximum absorption wavelength of this compound in toluene was 651 nm.

[0106] Synthesis Example 3 (Synthesis of anthraquinone compound represented by No. 14 of the above specific example) To 20 parts of NMP, 0.9 parts of the compound represented by formula (5A), 0.02 parts of copper powder, 0.02 parts of copper iodide, 2.2 parts of ethyl 4-iodo-1-benzoate, 0.02 parts of potassium carbonate, and 0.15 parts of sodium acetate were added and stirred at 140-150°C for 12 hours. The reaction solution was then cooled to 25°C, and 200 parts of methanol was added. The mixture was further stirred for 1 hour. The reaction product was collected by filtration, washed with methanol, and then dried in a hot air oven at 50°C for 24 hours. The resulting crude product was dissolved in toluene and purified using a column chromatography column with toluene as the developing solvent. The solvent was removed from the purified solution by vacuum distillation, and the mixture was dried in a hot air oven at 50°C for 24 hours to obtain 0.2 parts of the above compound represented by formula (5A) as a dark brown solid. The maximum absorption wavelength of this compound in toluene was 654 nm.

[0107] Example 1 (Preparation of Liquid Crystal Composition of the Present Invention) As the (B) liquid crystal material, 0.51 parts of 1-cyano-4'-n-pentylbiphenyl, 0.25 parts of 1-cyano-4'-n-heptylbiphenyl, 0.16 parts of 1-cyano-4'-n-octyloxybiphenyl, and 0.08 parts of 1-cyano-4''-n-pentylterphenyl were mixed with 0.0120 parts of the compound represented by Specific Example No. 1 and 0.0180 parts of the compound represented by Specific Example No. 101 as the (A) dye compound, and the resulting mixture was stirred on a hot plate at 70°C for 1 hour to prepare a liquid crystal composition of the present invention (the content of the (A) dye compound relative to the total amount of the (B) liquid crystal material was approximately 3.0% by mass).

[0108] Example 2 (Preparation of Liquid Crystal Composition of the Present Invention) As (B) liquid crystal materials, 0.51 parts of 1-cyano-4'-n-pentylbiphenyl, 0.25 parts of 1-cyano-4'-n-heptylbiphenyl, 0.16 parts of 1-cyano-4'-n-octyloxybiphenyl, and 0.08 parts of 1-cyano-4''-n-pentylterphenyl, and as (A) dye compounds, 0.0104 parts of compound represented by specific example No. 1, 0.0147 parts of compound represented by specific example No. 101, and 0.0049 parts of compound represented by specific example No. 202 were stirred on a hot plate at 70°C for 1 hour to prepare a liquid crystal composition of the present invention (the content of the (A) dye compound relative to the total amount of the (B) liquid crystal material was approximately 3.0% by mass).

[0109] Example 3 (Preparation of Liquid Crystal Composition of the Present Invention) As the (B) liquid crystal material, 0.51 parts of 1-cyano-4'-n-pentylbiphenyl, 0.25 parts of 1-cyano-4'-n-heptylbiphenyl, 0.16 parts of 1-cyano-4'-n-octyloxybiphenyl, and 0.08 parts of 1-cyano-4''-n-pentylterphenyl were mixed with 0.0104 parts of the compound represented by Specific Example No. 12, 0.0147 parts of the compound represented by Specific Example No. 101, and 0.0049 parts of the compound represented by Specific Example No. 220 as the (A) dye compounds, and the mixture was stirred on a hot plate at 70°C for 1 hour to prepare a liquid crystal composition of the present invention (the content of the (A) dye compound relative to the total amount of the (B) liquid crystal material was approximately 3.0% by mass).

[0110] Example 4 (Preparation of Liquid Crystal Composition of the Present Invention) As (B) liquid crystal materials, 0.51 parts of 1-cyano-4'-n-pentylbiphenyl, 0.25 parts of 1-cyano-4'-n-heptylbiphenyl, 0.16 parts of 1-cyano-4'-n-octyloxybiphenyl, and 0.08 parts of 1-cyano-4''-n-pentylterphenyl, and as (A) dye compounds, 0.0104 parts of compound No. 14, 0.0147 parts of compound No. 102, and 0.0049 parts of compound No. 213 were stirred on a hot plate at 70°C for 1 hour to prepare a liquid crystal composition of the present invention (the content of the (A) dye compound relative to the total amount of the (B) liquid crystal material was approximately 3.0% by mass).

[0111] Comparative Example 1 (Preparation of Comparative Liquid Crystal Composition) A liquid crystal composition of the present invention (the content of the (A) dye compound relative to the total amount of the (B) liquid crystal material) (the content of the (A) dye compound is approximately 3.0% by mass) was prepared in the same manner as in Example 1, except that the (A) dye compound was changed to 0.0104 parts of a compound represented by the following formula (X) disclosed in WO2022 / 138440, 0.0147 parts of a compound represented by the following formula (Y) disclosed in WO2022 / 158493, and 0.0049 parts of the compound represented by specific example No. 215.

[0112] [ka]

[0113] Comparative Example 2 (Preparation of Comparative Liquid Crystal Composition) A liquid crystal composition of the present invention (the content of the (A) dye compound relative to the total amount of the (B) liquid crystal material) (the content of the (A) dye compound is approximately 3.0% by mass) was prepared in the same manner as in Example 1, except that the (A) dye compound was changed to 0.0104 parts of a compound represented by the following formula (Z) disclosed in JP-B-03-063489, 0.0147 parts of a compound represented by the above formula (Y) disclosed in WO2022 / 158493, and 0.0049 parts of the compound represented by Specific Example No. 215.

[0114] [ka]

[0115] Example 5 (Preparation of light-controlling elements of the present invention and comparative examples) The liquid crystal composition obtained in Example 1 was sealed in a device with a gap of 15 μm between two glass substrates, each having a transparent electrode and having a surface in contact with the liquid crystal that had been subjected to a homogeneous alignment treatment by rubbing a polyamide resin.In the device, when no voltage was applied, the liquid crystal was in a homogeneous alignment state, and the dye molecules were also in a similar alignment state according to the liquid crystal.

[0116] Examples 6 to 8 (Fabrication of the light-adjusting element of the present invention) A light-adjusting element of the present invention was prepared in the same manner as in Example 5, except that the liquid crystal composition obtained in each of Examples 2 to 4 was used instead of the liquid crystal composition obtained in Example 1.

[0117] Comparative Examples 3 and 4 (Fabrication of Comparative Light-Controlling Devices) Comparative light control elements were prepared in the same manner as in Example 5, except that the liquid crystal compositions obtained in Comparative Examples 1 and 2 were used instead of the liquid crystal composition obtained in Example 1.

[0118] [Evaluation method] The physical properties of the light-adjustable elements obtained in Examples 6 to 8 and Comparative Example 4 were measured and evaluated as follows.

[0119] (Transmittance measurement of photochromic element) The transmittance (Kz) of linearly polarized light parallel to the alignment direction and the transmittance (Ky) of linearly polarized light perpendicular to the alignment direction of the light control elements obtained in Examples 6 to 8 and Comparative Example 2 were measured using a spectrophotometer (Hitachi, Ltd. "U-4100") The measurements were carried out over a wavelength range of 400 to 700 nm.

[0120] (Kz(Y) after luminosity correction, Ky(Y) after luminosity correction) For the photochromic elements obtained in Examples 5 to 8 and Comparative Example 4, the transmittance Kz for linearly polarized light parallel to the alignment direction, corrected for luminosity (Kz(Y)(%)), and the transmittance Ky for polarized light perpendicular to the alignment direction, corrected for luminosity (Ky(Y)(%)), were calculated. The luminosity-corrected Kz(Y)(%) and luminosity-corrected Ky(Y)(%) are transmittances corrected to luminosity according to JIS Z 8722:2009 for Ky and Kz at each wavelength, determined at predetermined wavelength intervals dλ (5 nm in this case) in the wavelength range of 400 to 700 nm. Specifically, the Kz and Ky values ​​for each wavelength were calculated by substituting them into the following formulas (I and II). In the formulas (I and II), Pλ represents the spectral distribution of standard light (illuminant C), and yλ represents the 2-degree visual field color matching function.

[0121]

number

[0122] (Calculating the dichroic ratio of a dimming element) For the light-control elements obtained in Examples 5 to 8 and Comparative Example 4, the dichroic ratio after luminosity correction in the range of 400 to 700 nm was calculated by calculating the absorbance ratio from the transmittance Kz (Y) (%) for linearly polarized light parallel to the alignment direction, which was corrected for luminosity, and the transmittance Ky (Y) (%) for polarized light perpendicular to the alignment direction, which was corrected for luminosity, using the following formula (III):

[0123]

number

[0124] [Table 7]

[0125] As shown in Table 7, it was confirmed that the light control devices of Examples 5 to 8 exhibited better dichroic ratios than the light control device of Comparative Example 4.

[0126] (Light resistance test of dimming element) A UV cut filter of 400 nm or less was attached to the light control elements obtained in Examples 5 to 8 and Comparative Example 3, and the light control elements were then subjected to irradiation at an illuminance of 650 W / m at a temperature of 63°C. 2 The light resistance test was carried out by irradiating the light-controlling element with a metal halide lamp for 300 hours. The transmittance in the range of 380 to 780 nm was measured with a spectrophotometer before and after the light resistance test, both when no voltage was applied and when a voltage (48 V) was applied. From the obtained transmission spectrum, the chromaticity (L * , a * , b * The color difference (ΔEab) before and after the light resistance test when no voltage was applied and when a voltage (48 V) was applied was calculated using the following calculation formula (iv): ΔE abThe smaller the value, the smaller the color change before and after the light resistance test, and the more excellent the light resistance. The results are shown in Table 8. ΔE ab (L * , a * , b * )={(ΔL * ) 2 +(Δa * ) 2 +(Δb * ) 2} 1 / 2 (iv)

[0127] [Table 8]

[0128] As shown in Table 8, the light control devices of Examples 5 to 8 had a lower ΔE than the light control device of Comparative Example 3 both when a voltage was applied and when no voltage was applied. ab It was confirmed that the light resistance was small and excellent.

[0129] (Hue a when voltage is applied to the dimming element * value, b * value) The transmittance of the light-controlling elements obtained in Examples 5 to 8 and Comparative Examples 3 and 4 was measured using a spectrophotometer, and the hue a was calculated in accordance with JIS Z 8781-4:2013. * value, b * The values ​​are shown in Table 9.

[0130] [Table 9]

[0131] As shown in Table 9, the dimming elements of Examples 5 to 8 have a * value, b * Both values ​​were less than 5, indicating achromaticity. Therefore, it was confirmed that the performance of the photochromic elements of Examples 5 to 8 was significantly improved compared to the photochromic elements of Comparative Examples 3 and 4 in that all of the properties, including dichroism, light resistance, and achromatic color, were well balanced and excellent.

[0132] Reference Example Using Compound Represented by General Formula (1-1) Reference Example 1 (Synthesis of anthraquinone compound represented by No. 1R in the above specific example) To 20 parts of NMP, 0.9 parts of the compound represented by the following formula (6A), 0.02 parts of copper powder, 0.02 parts of copper iodide, 2.4 parts of 1-heptyl-4-iodobenzene, 0.02 parts of potassium carbonate, and 0.15 parts of sodium acetate were added and stirred at 140-150°C for 12 hours. The reaction solution was then cooled to 25°C, and 200 parts of methanol was added. The mixture was further stirred for 1 hour. The reaction product was collected by filtration, washed with methanol, and then dried in a hot air dryer at 50°C for 24 hours. The resulting crude product was dissolved in toluene and purified using a column chromatography column with toluene as the developing solvent. The solvent was removed from the purified solution by distillation under reduced pressure, and the mixture was dried in a hot air dryer at 50°C for 24 hours to obtain 0.2 parts of the above compound represented by No. 1R as a dark brown solid. The maximum absorption wavelength of this compound in toluene was 646 nm.

[0133] [ka]

[0134] Reference Example 2 (Preparation of Reference Liquid Crystal Composition) A reference liquid crystal composition (the content of the (A) dye compound relative to the total amount of the (B) liquid crystal material was approximately 3.0% by mass) was prepared by heating and stirring for 1 hour on a hot plate at 70°C for 1 hour using 0.51 parts of 1-cyano-4'-n-pentylbiphenyl, 0.25 parts of 1-cyano-4'-n-heptylbiphenyl, 0.16 parts of 1-cyano-4'-n-octyloxybiphenyl, and 0.08 parts of 1-cyano-4''-n-pentylterphenyl as (B) liquid crystal materials, and 0.0104 parts of the compound represented by No. 1R, 0.0147 parts of the compound represented by No. 102, and 0.0049 parts of the compound represented by No. 213 as (A) dye compounds.

[0135] Reference example 3 (creating a dimming element for reference) The liquid crystal composition obtained in Reference Example 2 was sealed in a device with a gap of 15 μm between two glass substrates having transparent electrodes and having a surface in contact with the liquid crystal that had been subjected to a homogeneous alignment treatment by rubbing a polyamide resin on the surface that contacts the liquid crystal. In the light-control device, when no voltage was applied, the liquid crystal was in a homogeneous alignment state, and the dye molecules were also in a similar alignment state according to the liquid crystal.

[0136] [Methods for measuring and evaluating the physical properties of photochromic devices] For the light-control element obtained in Reference Example 3, the dichroic ratio was measured and calculated, the color difference was measured and calculated in a light resistance test, and the hue a when voltage was applied was measured and calculated. * value, b * The values ​​were measured and calculated as described above. The light-controlling element obtained in Reference Example 3 had a dichroic ratio of 12.7, and in a light resistance test, the color difference ΔEab when no voltage was applied and the color difference ΔEab when voltage was applied were 0.6 and 0.6, respectively, and the hue a * value and b * The values ​​were -3.0 and 3.2 (both less than 5), respectively. As described above, the photochromic element of Reference Example 3 was found to exhibit a good dichroic ratio, excellent light fastness, and achromatic color. That is, it was confirmed that the photochromic element of Reference Example 3 has significantly improved performance in that it has a well-balanced and excellent overall property of dichroism, light fastness, and achromatic color compared to photochromic elements according to conventional techniques, such as the photochromic elements of Comparative Examples 3 and 4. [Industrial Applicability]

[0137] The light-controlling liquid crystal composition of the present invention can stably maintain a high dye concentration, and by using the composition, a light-controlling device excellent in solubility and contrast can be obtained. The light-controlling device obtained by the present invention can be used for construction materials such as windows, partitions, and doors, automotive materials such as windows and sunroofs, displays that show letters and numbers, and materials for exhibits such as show windows.

Claims

1. A liquid crystal composition containing (A) a dye compound and (B) a liquid crystal material, wherein the dye compound (A) is a compound represented by the following general formula (1): 【Chemical 1】 (In the formula, R １ represents a hydrogen atom, a linear or branched alkoxy group having 1 to 12 carbon atoms, a halogen atom, ２ R ８ , -OCOR ８ , -COR ８ , a cyano group, or a trifluoromethyl group. ４ , R ５ , R ６、 R ７ , each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a halogen atom, —CO ２ R ８ , -OCOR ８ , -COR ８ , a cyano group, or a trifluoromethyl group. ２ , R ３ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, a linear or branched alkoxy group having 1 to 12 carbon atoms, or a group represented by the following formula (a): 【Chemistry 2】 (In formula (a), R ９ represents a hydrogen atom or a linear or branched alkyl group having 1 to 8 carbon atoms. ９ When there are multiple, they may be the same or different.) represents a substituent represented by R ８ each independently represents a linear or branched alkyl group having 1 to 12 carbon atoms, 【Chemistry 3】 (In formula (b), R １０ represents a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, or a linear or branched alkoxy group having 1 to 8 carbon atoms. １０ When a plurality of groups are present, they may be the same or different. 【Chemistry 4】 (In formula (c), R １１ represents a hydrogen atom or a linear or branched alkyl group having 1 to 8 carbon atoms. １１ When there are multiple, they may be the same or different.) An anthraquinone compound represented by the formula: The following general formula (2) 【Chemistry 5】 (In the formula, R １２ represents a hydrogen atom, a linear or branched alkyl group having 1 to 12 carbon atoms, or a linear or branched alkoxy group having 1 to 12 carbon atoms. １３ represents a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, or a linear or branched alkoxy group having 1 to 8 carbon atoms. A liquid crystal composition comprising an anthraquinone compound represented by the formula:

2. 2. The liquid crystal composition according to claim 1, wherein the mass ratio of the anthraquinone compound represented by the general formula (1) to the anthraquinone compound represented by the general formula (2) is 2:1 to 1:

2.

3. 2. The liquid crystal composition according to claim 1, wherein the concentration of the dye compound (A) contained in the liquid crystal composition relative to the liquid crystal material (B) is 0.5 to 10% by mass.

4. 2. The liquid crystal composition according to claim 1, comprising the anthraquinone compound represented by the general formula (1) and a dichroic dye other than the anthraquinone compound represented by the general formula (2).

5. A light-adjusting element comprising a pair of opposing substrates, at least one of which is a transparent substrate having a transparent electrode, and the liquid crystal composition according to claim 1 sandwiched between the pair of substrates.

6. 6. The light-adjusting element according to claim 5, wherein both of the pair of substrates are transparent substrates having transparent electrodes.

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