CN112867965A

CN112867965A - Liquid crystal composite and liquid crystal light-adjusting element

Info

Publication number: CN112867965A
Application number: CN201980068821.XA
Authority: CN
Inventors: 斋藤将之; 藤田浩章
Original assignee: JNC Corp; JNC Petrochemical Corp
Current assignee: JNC Corp; JNC Petrochemical Corp
Priority date: 2018-10-30
Filing date: 2019-07-30
Publication date: 2021-05-28
Also published as: JPWO2020090173A1; WO2020090173A1; TW202028437A

Abstract

The present invention provides a liquid crystal composite suitable for dimming, which contains a liquid crystal composition satisfying at least one of characteristics such as a high upper limit temperature, a low lower limit temperature, a low viscosity, a large optical anisotropy, and a large negative dielectric anisotropy, or having an appropriate balance between at least two of these characteristics, and a liquid crystal dimming element having the liquid crystal composite. A liquid crystal composite comprising a liquid crystal composition containing a specific compound having a large negative dielectric anisotropy and a polymer, the liquid crystal composite may further contain a specific compound having a high upper limit temperature or a low lower limit temperature.

Description

Liquid crystal composite and liquid crystal light-adjusting element

Technical Field

The present invention generally relates to a liquid crystal light adjusting device. More specifically, the present invention relates to a liquid crystal light control element having a liquid crystal composite in which a polymer and a liquid crystal composition are combined.

Background

A method of scattering light or the like is used for the liquid crystal light control element. Such an element is used in a building material such as a window glass or a partition of a room, a vehicle-mounted part, or the like. In these devices, a soft substrate such as a plastic film is used in addition to a hard substrate such as a glass substrate. In the liquid crystal composition sandwiched between these substrates, the arrangement of liquid crystal molecules is changed by adjusting the applied voltage. In this way, since light transmitted through the liquid crystal composition can be controlled, the liquid crystal light control element is widely used in a display, an optical shutter, a light control window (conventional document 1), a smart window (conventional document 2), and the like.

An example of the liquid crystal light control element is a polymer dispersed type of light scattering mode. The liquid crystal composition is dispersed in the polymer. The element has the following features. The element is easy to manufacture. Since the film thickness can be easily controlled over a large area, a device with a large screen can be manufactured. A polarizing plate is not required, and thus a vivid display can be achieved. The angle of view is wide due to light scattering. The element has such excellent properties and is expected to be used for a light control glass, a projection display, a large-area display, and the like.

Another example is a polymer network (polymer network) type liquid crystal dimming element. In this type of element, the liquid crystal composition is present in a three-dimensional network of polymers. The composition is continuous, unlike the polymer dispersed type. This type of device also has the same characteristics as the polymer dispersed device. There are also liquid crystal light control elements in which a polymer network type and a polymer dispersion type are mixed.

A liquid crystal composition having appropriate characteristics is used for the liquid crystal light control element. By improving the properties of the composition, elements with good properties can be obtained. The correlation between the properties of both is summarized in the following Table 1. The properties of the composition are further illustrated on an element basis. The temperature range of the nematic phase is associated with the temperature range in which the element can be used. The upper limit temperature of the nematic phase is preferably about 70 ℃ or higher, and the lower limit temperature of the nematic phase is preferably about-20 ℃ or lower. The viscosity of the composition correlates to the response time of the element. In order to control the transmittance of light, the response time is preferably short. Ideally shorter than 1 millisecond of response time. Therefore, it is preferable that the viscosity of the composition is small. Further, it is preferable that the viscosity at low temperature is low.

TABLE 1 characteristics of liquid crystal compositions and liquid crystal dimming elements

Numbering	Characteristics of liquid Crystal composition	Characteristics of liquid crystal light-adjusting element
			1	Wide temperature range of nematic phase	Wide temperature range
2	Low viscosity	Short response time
			3	Large optical anisotropy	High haze
4	Large positive or negative dielectric anisotropy	Low threshold voltage and low power consumption
			5	Has large specific resistance	High voltage holding ratio
6	Is stable to light and heat	Long service life
			7	Large elastic constant	Short response time

The optical anisotropy of the composition is correlated with the haze ratio of the liquid crystal dimming element. The haze ratio is a ratio of diffused light to total transmitted light. When light is blocked, the haze ratio is preferably large. It is preferable for a large haze ratio that the optical anisotropy is large. The large dielectric anisotropy of the composition contributes to a low threshold voltage or a low power consumption in the device. Therefore, the dielectric anisotropy is preferably large. The large specific resistance of the composition contributes to a large voltage holding ratio in the device. Thus, a composition having a large specific resistance in the initial stage is preferable. Preferred are compositions having a large specific resistance even after long-term use. The stability or weatherability of the composition to light or heat is correlated to the lifetime of the element. When the stability or weather resistance is good, the life is long. Poor display such as afterimages or drip marks are also associated with the life of the element. An element having high weather resistance and less prone to display defects is desired.

The liquid crystal dimming element has a normal mode (normal mode) and a reverse mode (reverse mode). In the normal mode, it is opaque when no voltage is applied and becomes transparent when a voltage is applied. In the reverse mode, it is transparent when no voltage is applied and becomes opaque when a voltage is applied. An element that becomes transparent in the reverse mode when a failure occurs in the element is expected to be used in a window of an automobile or the like.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. H06-273725

Patent document 2: international publication No. 2011-

Patent document 3: japanese patent laid-open No. 63-278035

Patent document 4: japanese patent laid-open No. Hei 01-198725

Patent document 5: japanese patent laid-open publication No. Hei 07-104262

Patent document 6: japanese patent laid-open publication No. Hei 07-175045

Disclosure of Invention

Problems to be solved by the invention

The present invention addresses the problem of providing a liquid crystal composite suitable for dimming, which contains a liquid crystal composition that satisfies at least one of the characteristics of a high upper limit temperature of a nematic phase, a low lower limit temperature of the nematic phase, a low viscosity, a large optical anisotropy, a large negative dielectric anisotropy, a large specific resistance, a high stability to light, a high stability to heat, and a large elastic constant. Another object is to provide a liquid crystal composite suitable for dimming, which contains a liquid crystal composition having an appropriate balance between at least two of these characteristics. Still another object is to provide a liquid crystal light control element having such a liquid crystal composite. Still another object is to provide a liquid crystal light-controlling element having characteristics such as a short response time, a high voltage holding ratio, a low threshold voltage, a high haze ratio, a high weather resistance, and a long life.

Means for solving the problems

The present invention relates to a liquid crystal light control element or the like having a liquid crystal composite body which comprises a liquid crystal composition containing at least one compound selected from compounds represented by the formula (1) as a first component and a polymer and has an illuminance of 180W/m²And a haze change rate of 20% or less before and after a weather resistance test conducted under conditions in which the irradiation time is 100 hours and the in-cell temperature is 35 ℃.

In the formula (1), R¹And R²Is hydrogen, alkyl group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, alkenyl group having 2 to 12 carbon atoms, alkenyloxy group having 2 to 12 carbon atoms, or alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine; ring A and ring C are 1, 4-cyclohexylene, 1, 4-cyclohexenylene, tetrahydropyran-2, 5-diyl, 1, 4-phenylene in which at least one hydrogen is substituted by fluorine or chlorine, naphthalene-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine, chroman-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine, or chroman-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine; ring B is 2, 3-difluoro-1, 4-phenylene, 2-chloro-3-fluoro-1, 4-phenylene, 2, 3-difluoro-5-methyl-1, 4-phenylene, 3,4, 5-trifluoronaphthalene-2, 6-diyl, 7, 8-difluorochromane-2, 6-diyl, 3,4,5, 6-tetrafluorofluorene-2, 7-diyl, 4, 6-difluorodibenzofuran-3, 7-diyl, 4, 6-difluorodibenzothiophene-3, 7-diyl, or 1,1,6, 7-tetrafluoroindan-2, 5-diyl; z¹And Z²Is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy; a is 0, 1,2, or 3, b is 0 or 1; and the sum of a and b is 3 or less.

ADVANTAGEOUS EFFECTS OF INVENTION

The present invention is advantageous in that it provides a liquid crystal composite suitable for light control, which contains a liquid crystal composition that satisfies at least one of characteristics such as a high upper limit temperature of a nematic phase, a low lower limit temperature of the nematic phase, a low viscosity, a large optical anisotropy, a large negative dielectric anisotropy, a large specific resistance, a high stability to light, a high stability to heat, and a large elastic constant. Another advantage resides in providing a liquid crystal composite suitable for dimming that contains a liquid crystal composition having a proper balance between at least two of these characteristics. Still another advantage is to provide a liquid crystal dimming device having such a liquid crystal composite. Still another advantage is to provide a liquid crystal light modulating element having characteristics such as a short response time, a large voltage holding ratio, a low threshold voltage, a large haze ratio, a high weather resistance, and a long lifetime.

Detailed Description

In this specification, terms such as "liquid crystal compound", "polymerizable compound", "liquid crystal composition", "polymerizable composition", "liquid crystal composite", and "liquid crystal light control element" are used. The "liquid crystalline compound" is a general term for compounds having a liquid crystal phase such as a nematic phase or a smectic phase, and compounds which do not have a liquid crystal phase but are added to the composition for the purpose of adjusting the characteristics such as the temperature range, viscosity, and dielectric anisotropy of the nematic phase. The compound has a six-membered ring such as 1, 4-cyclohexylene or 1, 4-phenylene, and its molecular structure is rod-like (rod like). The "polymerizable compound" is a compound added for the purpose of forming a polymer in the liquid crystal composition. The liquid crystalline compound having an alkenyl group is not classified into a polymerizable compound in terms of its meaning.

The "liquid crystal composition" is prepared by mixing a plurality of liquid crystalline compounds. Additives such as optically active compounds, antioxidants, ultraviolet absorbers, pigments, antifoaming agents, and polar compounds may be added to the liquid crystal composition as required. Even in the case where an additive is added, the proportion of the liquid crystalline compound is represented by a mass percentage (mass%) based on the mass of the liquid crystal composition containing no additive. The proportion of the additive is represented by mass percentage based on the mass of the liquid crystal composition containing no additive. That is, the ratio of the liquid crystalline compound or the additive is calculated based on the total mass of the liquid crystalline compound.

The "polymerizable composition" is prepared by mixing a polymerizable compound into a liquid crystal composition. That is, the polymerizable composition is a mixture of at least one polymerizable compound and the liquid crystal composition. To the polymerizable compound, additives such as a polymerization initiator and a polymerization inhibitor are added as necessary. The ratio of the polymerization initiator and the polymerization inhibitor is represented by mass percentage based on the mass of the polymerizable compound. In the case where an additive is added, the proportion of the polymerizable compound or the liquid crystal composition contained in the polymerizable composition is also represented by a mass percentage based on the polymerizable composition containing no additive. The "liquid crystal composite" is produced by polymerization treatment of the polymerizable composition. The "liquid crystal light control element" is a generic name of a liquid crystal panel and a liquid crystal module having a liquid crystal composite and used for light control.

The "upper limit temperature of the nematic phase" may be simply referred to as "upper limit temperature". The "lower limit temperature of the nematic phase" may be simply referred to as "lower limit temperature". The expression "increase in dielectric anisotropy" means that the value increases positively in a composition having positive dielectric anisotropy, and increases negatively in a composition having negative dielectric anisotropy. The "large voltage holding ratio" means that the device has a large voltage holding ratio not only at room temperature but also at a temperature close to the upper limit temperature in the initial stage, and also has a large voltage holding ratio not only at room temperature but also at a temperature close to the upper limit temperature after long-term use. The properties of the composition or the element are sometimes investigated by time-varying tests.

The compound (1z) is exemplified. In formula (1z), symbols α and β surrounded by hexagons correspond to ring α and ring β, respectively, and represent a six-membered ring, a condensed ring, and the like. Where the subscript 'x' is 2, there are two rings α. The two groups represented by the two rings a may be the same or may also be different. This rule applies to any two rings a where subscript 'x' is greater than 2. This rule also applies to other symbols such as the bonding base Z. The slash across one side of the loop β indicates that any hydrogen on the loop β may be substituted with a substituent (-Sp-P). The subscript 'y' indicates the number of substituents that are substituted. When subscript 'y' is 0, there is no such substitution. When the subscript 'y' is 2 or more, a plurality of substituents (-Sp-P) are present on the ring β. In this case, rules "may be the same or may be different" may also apply. Furthermore, this rule also applies to the use of the notation of Ra in a variety of compounds.

In formula (1z), for example, the expression "Ra and Rb are alkyl, alkoxy, or alkenyl" means that Ra and Rb are independently selected from the group of alkyl, alkoxy, and alkenyl. That is, the group represented by Ra and Rb may be the same or different.

At least one compound selected from the compounds represented by the formula (1z) may be simply referred to as "compound (1 z)". The "compound (1 z)" means one compound, a mixture of two compounds, or a mixture of three or more compounds represented by the formula (1 z). The same applies to the compounds represented by the other formulae. The expression "at least one compound selected from the group consisting of the compounds represented by the formula (1z) and the formula (2 z)" means at least one compound selected from the group consisting of the compound (1z) and the compound (2 z).

The expression of "at least one ' A '" means 'The number of A's is arbitrary. The expression "at least one 'a' may be substituted with 'B' means that the position of 'a' is arbitrary when the number of 'a' is one, and the position thereof may be selected without limitation when the number of 'a' is two or more. Sometimes using "at least one-CH₂-may be substituted by-O-. In this case, -CH₂-CH₂-CH₂Can pass through non-contiguous-CH₂-conversion to-O-CH by-O-substitution₂-O-. However, adjacent-CH₂-is not substituted by-O-. This is because-O-CH is formed in this substitution₂- (peroxides).

The alkyl group of the liquid crystalline compound is linear or branched and does not include a cyclic alkyl group. Straight chain alkyls are preferred over branched alkyls. The same applies to terminal groups such as alkoxy groups and alkenyl groups. In order to increase the upper limit temperature, the steric configuration associated with the 1, 4-cyclohexylene group is a trans configuration rather than a cis configuration. Since 2-fluoro-1, 4-phenylene is asymmetric in the left-right direction, it is present in the left (L) and right (R) directions.

The same applies to divalent radicals such as tetrahydropyran-2, 5-diyl. The same applies to a bonding group (-COO-or-OCO-) such as a carbonyloxy group.

The present invention is as follows.

Item 1. a liquid crystal dimming element having a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from the compounds represented by formula (1) as a first component and a polymer, and having an illuminance of 180W/m²And a haze change rate of 20% or less before and after a weather resistance test conducted under conditions in which the irradiation time is 100 hours and the in-cell temperature is 35 ℃.

Item 2. the liquid crystal dimming element according to item 1, which has a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from the compounds represented by formulae (1-1) to (1-35) as a first component, and a polymer.

In the formula (1)1-1) to formula (1-35), R¹And R²Is hydrogen, alkyl group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, alkenyl group having 2 to 12 carbon atoms, alkenyloxy group having 2 to 12 carbon atoms, or alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine.

Item 3. the liquid crystal dimming element according to item 1 or item 2, wherein the proportion of the first component is in a range of 20 to 90 mass% based on the mass of the liquid crystal composition.

Item 4. the liquid crystal dimming element according to any one of items 1 to 3, which has a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from the compounds represented by formula (2) as a second component, and a polymer.

In the formula (2), R³And R⁴Is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine, or an alkenyl group having 2 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine; ring D and ring E are 1, 4-cyclohexylene, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, or 2, 5-difluoro-1, 4-phenylene; z³Is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy; c is 1,2, or 3.

Item 5. the liquid crystal dimming element according to any one of items 1 to 4, which has a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from the compounds represented by formulae (2-1) to (2-13) as a second component, and a polymer.

In the formulae (2-1) to (2-13), R³And R⁴Is alkyl group having 1 to 12 carbon atoms, carbon numberAn alkoxy group of 1 to 12, an alkenyl group of 2 to 12 carbon atoms, an alkyl group of 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine, or an alkenyl group of 2 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine.

Item 6. the liquid crystal dimming element according to item 4 or item 5, wherein the ratio of the second component is in a range of 10 to 80 mass% based on the mass of the liquid crystal composition.

The liquid crystal dimming element according to any one of claims 1 to 6, wherein the polymer is a polymer derived from a mixture of polymerizable compounds containing a compound represented by formula (3) as a main component.

P¹-Z⁴-P² (3)

In formula (3), Z⁴Is C1-20 alkylene, wherein at least one hydrogen may be substituted by C1-5 alkyl, fluorine, chlorine, or P³Substituted by at least one-CH₂May be substituted by-O-, -CO-, -COO-, -OCO-, -NH-, or-N (R)⁵) -substituted, at least one-CH₂-CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one-CH₂May be substituted by a divalent group generated by removing two hydrogens from a carbocyclic saturated aliphatic compound, a heterocyclic saturated aliphatic compound, a carbocyclic unsaturated aliphatic compound, a heterocyclic unsaturated aliphatic compound, a carbocyclic aromatic compound, or a heterocyclic aromatic compound, in which the number of carbons is 5 to 35, and at least one hydrogen may be substituted by R⁵Or P³Substituted, here, R⁵Is an alkyl group having 1 to 12 carbon atoms, in which at least one-CH group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-; p¹、P²And P³Is a polymerizable group.

Item 8 the liquid crystal dimming element according to item 7, wherein P¹、P²And P³Is a group selected from the polymerizable groups represented by the formulae (P-1) to (P-6).

In formulae (P-1) to (P-6), M¹、M²And M³Hydrogen, fluorine, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 5 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine.

Item 9 the liquid crystal dimming element according to item 7, wherein P¹、P²And P³Is an acryloyloxy group or a methacryloyloxy group.

The liquid crystal dimming element according to any one of claims 1 to 6, wherein the polymer is a polymer derived from a mixture of polymerizable compounds containing a compound represented by formula (4) as a main component.

In formula (4), M⁴And M⁵Is hydrogen or methyl; z⁵Is alkylene group having 21 to 80 carbon atoms, in which at least one hydrogen may be substituted by alkyl group having 1 to 20 carbon atoms, fluorine, or chlorine, and at least one-CH₂May be substituted by-O-, -CO-, -COO-, -OCO-, -NH-, or-N (R)⁵) -substituted, at least one-CH₂-CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, where R is⁵Is an alkyl group having 1 to 12 carbon atoms, in which at least one-CH group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

The liquid crystal dimming element according to any one of claims 1 to 6, wherein the polymer is a polymer derived from a mixture of polymerizable compounds containing a compound represented by formula (5) as a main component.

In formula (5), M⁶Is hydrogen or methyl; z⁶Is a single bond or an alkylene group having 1 to 5 carbon atoms, in which alkylene group at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂May be substituted by-O-, -CO-, -COO-, or-OCO-substitution; r⁶Is an alkyl group having 1 to 40 carbon atoms, in which at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-, at least one-CH₂May be substituted by a divalent group generated by removing two hydrogens from a carbocyclic saturated aliphatic compound, a heterocyclic saturated aliphatic compound, a carbocyclic unsaturated aliphatic compound, a heterocyclic unsaturated aliphatic compound, a carbocyclic aromatic compound, or a heterocyclic aromatic compound, in which the carbon number is 5 to 35, and at least one hydrogen may be substituted by an alkyl group having a carbon number of 1 to 12, in which at least one-CH-group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

Item 12 the liquid crystal dimming element according to item 11, wherein in formula (5), M⁶Is hydrogen or methyl; z⁶Is a single bond or an alkylene group having 1 to 5 carbon atoms, in which alkylene group at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-; r⁶Is an alkyl group having 1 to 40 carbon atoms, in which at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

An item 13 is the liquid crystal dimming element according to any one of items 1 to 6, wherein the polymer is a polymer derived from a mixture of polymerizable compounds containing a compound selected from the group consisting of compounds represented by formula (6), formula (7), and formula (8) as a main component.

In the formulae (6), (7) and (8), the ring F, the ring G, the ring I, the ring J, the ring K and the ring L are 1, 4-cyclohexylene, 1, 4-phenylene, 1, 4-cyclohexenylene, pyridine-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, naphthalene-2, 6-diyl or fluorene-2, 7-diyl, and here, at least one hydrogen may be fluorine, chlorine, cyano, hydroxyl, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, an alkyl group having 1 to 5 carbon atoms or a fluorine-2, 7-diyl group1 to 5 alkoxy, 1 to 5 alkoxycarbonyl, or 1 to 5 alkanoyl; z⁷、Z⁹、Z¹¹、Z¹²And Z¹⁶Is a single bond, -O-, -COO-, -OCO-, or-OCOO-; z⁸、Z¹⁰、Z¹³And Z¹⁵Is a single bond, -OCH₂-、-CH₂O-、-COO-、-OCO-、-COS-、-SCO-、-OCOO-、-CONH-、-NHCO-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CF₂CF₂-、-CH＝CHCOO-、-OCOCH＝CH-、-CH₂CH₂COO-、-OCOCH₂CH₂-、-CH＝CH-、-N＝CH-、-CH＝N-、-N＝C(CH₃)-、-C(CH₃) -N-, -N-, or-C ≡ C-; z¹⁴Is a single bond, -O-or-COO-; x is hydrogen, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, cyano, alkyl of carbon number 1 to 20, alkenyl of carbon number 2 to 20, alkoxy of carbon number 1 to 20, or alkoxycarbonyl of carbon number 1 to 20; e and g are integers from 1 to 4; j and l are integers from 0 to 3; the sum of j and l is 1 to 4; d. f, h, i, k, and m are integers from 0 to 20; m⁷To M¹²Is hydrogen or methyl.

Item 14. the liquid crystal dimming element according to any one of items 1 to 13, wherein a ratio of the liquid crystal composition is in a range of 50% by mass to 95% by mass, and a ratio of the polymer is in a range of 5% by mass to 50% by mass, based on a mass of the liquid crystal composite.

The liquid crystal light-controlling element according to any one of claims 1 to 14, wherein the liquid crystal composite is obtained using a polymerizable composition containing a liquid crystal composition and a polymerizable compound as a precursor, the polymerizable composition containing a photopolymerization initiator as an additive.

The liquid crystal light-adjusting element according to any one of items 1 to 15, wherein the light-adjusting layer is the liquid crystal composite according to any one of items 1 to 15, and the light-adjusting layer is sandwiched by a pair of transparent substrates having transparent electrodes.

Item 17 the liquid crystal dimming element of item 16, wherein the transparent substrate is a glass plate or an acryl plate.

The liquid crystal dimming element according to claim 16, wherein the transparent substrate is a plastic film.

The light modulation window of item 19, using the liquid crystal light modulation element of any one of items 16 to 18.

The smart window of any one of items 16 to 18, wherein the liquid crystal dimming element is used.

Item 21. use of a liquid crystal dimming element according to any one of items 1 to 18 in a dimming window.

Item 22. use of a liquid crystal dimming element according to any one of items 1 to 18 in a smart window.

The present invention also includes the following items. (a) The liquid crystal dimming element according to item 2, which has a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from the group consisting of the compound (1-1), the compound (1-3), the compound (1-6), the compound (1-8), the compound (1-10), the compound (1-14), and the compound (1-34) described in item 2 as a first component, and a polymer.

(b) The liquid crystal dimming element according to item 5, which has a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from the group consisting of the compound (2-1), the compound (2-3), the compound (2-5), the compound (2-6), the compound (2-7), and the compound (2-8) described in item 5 as a second component, and a polymer.

The present invention also includes the following items. (c) The liquid crystal light-controlling element as described above, wherein the ratio of the liquid crystal composition is in the range of 50 to 90 mass% and the ratio of the polymer is in the range of 10 to 50 mass% based on the mass of the liquid crystal composite. (d) The liquid crystal light-controlling element as described above, wherein the ratio of the liquid crystal composition is in the range of 50 to 85 mass% and the ratio of the polymer is in the range of 15 to 50 mass% based on the mass of the liquid crystal composite. (e) The liquid crystal dimming element as described above, wherein the ratio of the liquid crystal composition is in the range of 60 to 80 mass% and the ratio of the polymer is in the range of 20 to 40 mass% based on the mass of the liquid crystal composite.

The liquid crystal dimming element of the present invention is explained in the following order. First, the structure of the liquid crystal composite will be explained. Second, the structure of the liquid crystal composition will be described. Third, the main characteristics of the liquid crystalline compound and the main effects of the compound on the liquid crystalline composition or the device will be described. Fourth, the combination of components, the preferred ratio of the components, and the basis thereof in the liquid crystal composition will be described. Fifth, a preferred embodiment of the liquid crystalline compound will be described. Sixth, a preferred liquid crystalline compound is shown. Seventh, a preferred embodiment of the polymerizable compound and an example thereof will be described. Eighth, a method for synthesizing the component compound will be explained. Ninth, additives that can be added to the polymerizable composition will be described. Finally, the liquid crystal composite or the element will be explained.

First, the structure of the liquid crystal composite will be explained. The liquid crystal composite is obtained by polymerizing the polymerizable composition. The polymerizable composition is a mixture of a liquid crystal composition and a polymerizable compound. The dielectric anisotropy of the liquid crystal composition is negative. The polymerizable composition provides a liquid crystal composite because a polymer produced by polymerization undergoes phase separation. That is, a liquid crystal composite is produced by combining a polymer and a liquid crystal composition. The liquid crystal composite is suitable for an element which is transparent when no voltage is applied and becomes opaque in a reverse mode when a voltage is applied. The optical anisotropy of the liquid crystal composition is associated with the refractive index of the polymer and the transparency of the liquid crystal dimming element. In general, the optical anisotropy (Δ n) of the liquid crystal composition is preferably large. The optical anisotropy is preferably 0.15 or more, more preferably 0.18 or more.

In the polymer dispersion type device, the liquid crystal composition is dispersed in the polymer as droplets. The individual droplets are separated and not continuous. On the other hand, in the polymer network type element, the polymer has a three-dimensional lattice structure, and the liquid crystal composition is surrounded by the lattice but is continuous. In these elements, the ratio of the liquid crystal composition based on the liquid crystal composite is preferably large in order to efficiently generate light scattering. The driving voltage is lowered by reducing the droplet or the grid, and therefore the proportion of the polymer is preferably large.

The preferable proportion of the liquid crystal composition is in the range of about 50% by mass to about 95% by mass based on the mass of the liquid crystal composite. The preferred ratio also ranges from about 50% to about 90% by mass. Further, the preferable ratio is in the range of about 50% by mass to about 85% by mass. A particularly preferred ratio is in the range of about 60% to about 80% by mass. A particularly preferred ratio is in the range of about 70% to about 80% by mass. The ratio of the polymer can be easily calculated because the total of the liquid crystal composite and the polymer is 100% by mass. The ratio of the polymer based on the liquid crystal composite is the same as the ratio of the polymerizable compound based on the polymerizable composition.

When the ratio of the liquid crystal composition to the polymer is in these ranges, a polymer network type element is produced. When the proportion of the polymer is large, a polymer-dispersed structure is mixed. On the other hand, when the proportion of the polymer is less than about 5% by mass, a polymer-stabilized alignment type element is produced. It is abbreviated as PSA (polymer stabilized alignment) element. In example 1 of International publication No. 2012-050178, "the monomer is added in an amount of 0.5 wt% based on the liquid crystal material" (paragraph 0105). As is clear from the above description, a slight amount of a polymerizable compound is added to a liquid crystal material (liquid crystal composition) in a PSA element.

In the PSA element, the polymer adjusts the pretilt angle of the liquid crystal molecules. By optimizing the pretilt angle, the liquid crystal molecules are stabilized, and the response time of the element is shortened. On the other hand, in the polymer network type element of the reverse mode, liquid crystal molecules are vertically aligned by the action of the alignment film, and thus the element is transparent. When a voltage is applied to the element, liquid crystal molecules are aligned parallel to the substrates. The refractive index of the polymer differs from that of the liquid crystal molecules, thereby causing light scattering and rendering the element opaque. Thus, in the polymer network type element, a polarizing plate is not required unlike the PSA element.

Second, the structure of the liquid crystal composition will be described. The composition contains a plurality of liquid crystalline compounds. The composition may also contain additives. The additive is optically active compound, antioxidant, ultraviolet absorbent, pigment, defoaming agent, polar compound, etc. From the viewpoint of the liquid crystalline compound, the compositions are classified into composition a and composition B. The composition a may further contain other liquid crystalline compounds, additives, and the like in addition to the liquid crystalline compound selected from the compounds (1) and (2). The "other liquid crystalline compound" is a liquid crystalline compound different from the compound (1) and the compound (2). Such compounds are mixed in the composition for the purpose of further adjusting the properties.

The composition B substantially contains only a liquid crystalline compound selected from the compound (1) and the compound (2). "substantially" means that the composition B may contain additives but does not contain other liquid crystalline compounds. The amount of ingredients of composition B is small compared to composition a. From the viewpoint of cost reduction, composition B is superior to composition a. From the viewpoint that the characteristics can be further adjusted by mixing other liquid crystalline compounds, the composition a is superior to the composition B.

Third, the main characteristics of the liquid crystalline compound and the main effects of the compound on the liquid crystalline composition or the device will be described. The main properties of the component compounds based on the effects of the present invention are summarized in Table 2. In the notation of table 2, L means large or high, M means moderate, and S means small or low. The notation L, M, S is a classification based on qualitative comparisons between component compounds, with 0 (zero) meaning extremely small.

TABLE 2 Properties of liquid crystalline Compounds

Compound (I)	Chemical combinationThing (1)	Compound (2)
			Upper limit temperature	S～L	S～L
Viscosity of the oil	M～L	S～M
			Optical anisotropy	M～L	S～L
Dielectric anisotropy	M～L¹⁾	0
			Specific resistance	L	L

1) The value of the dielectric anisotropy is negative, and the symbol indicates the magnitude of the absolute value

The main effects of the component compounds on the properties of the composition are as follows. The compound (1) improves dielectric anisotropy. The compound (2) raises the upper limit temperature or lowers the lower limit temperature.

Fourth, the combination of components, the preferred ratio of the components, and the basis thereof in the liquid crystal composition will be described. A preferred combination of ingredients in the composition is the first ingredient + the second ingredient.

The preferred proportion of the first component is about 20% by mass or more in order to improve the dielectric anisotropy, and about 90% by mass or less in order to lower the lower limit temperature. Further, the preferable ratio is in the range of about 25 mass% to about 85 mass%. A particularly preferred ratio is in the range of about 30% by mass to about 80% by mass.

The preferable ratio of the second component is about 10 mass% or more for increasing the upper limit temperature or decreasing the lower limit temperature, and about 80 mass% or less for increasing the dielectric anisotropy. Further, the preferable ratio is in the range of about 15% by mass to about 75% by mass. A particularly preferred ratio is in the range of about 20% by mass to about 70% by mass.

Fifth, a preferred embodiment of the liquid crystalline compound will be described. In the formulae (1) and (2), R¹And R²Is hydrogen, alkyl group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, alkenyl group having 2 to 12 carbon atoms, alkenyloxy group having 2 to 12 carbon atoms, or alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine. Preferred R is for improving stability to light or heat¹Or R²Is an alkyl group having 1 to 12 carbon atoms, and R is preferably selected to improve dielectric anisotropy¹Or R²Is alkoxy with 1 to 12 carbon atoms.

R³And R⁴Is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms wherein at least one hydrogen is substituted with fluorine or chlorine, or an alkenyl group having 2 to 12 carbon atoms wherein at least one hydrogen is substituted with fluorine or chlorine. For increasing the upper limit temperature or for decreasing the lower limit temperature, R is preferred³Or R⁴R is an alkenyl group having 2 to 12 carbon atoms, and is preferably selected from the group consisting of³Or R⁴Is an alkyl group having 1 to 12 carbon atoms.

Preferred alkyl groups are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or octyl. Further preferred alkyl groups for reducing the viscosity are methyl, ethyl, propyl, butyl, or pentyl groups.

Preferred alkoxy groups are methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, or heptyloxy. Further preferred alkoxy groups for reducing the viscosity are methoxy or ethoxy.

Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl. Further preferable alkenyl groups for reducing the viscosity are vinyl, 1-propenyl, 3-butenyl, or 3-pentenyl. The preferred steric configuration of-CH ═ CH-in these alkenyl groups depends on the position of the double bond. For reasons of viscosity reduction and the like, the trans configuration is preferred among alkenyl groups such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, 3-pentenyl, 3-hexenyl. Among alkenyl groups such as 2-butenyl, 2-pentenyl, 2-hexenyl, the cis configuration is preferred.

Preferred alkenyloxy groups are vinyloxy, allyloxy, 3-butenyloxy, 3-pentenyloxy, or 4-pentenyloxy. Further preferred alkenyloxy groups for reducing the viscosity are allyloxy or 3-butenyloxy.

Preferred examples of alkyl groups in which at least one hydrogen is substituted by fluorine or chlorine are fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, 5-fluoropentyl, 6-fluorohexyl, 7-fluoroheptyl, or 8-fluorooctyl. Further preferable examples are 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl and 5-fluoropentyl for improving the dielectric anisotropy.

Preferred examples of alkenyl groups in which at least one hydrogen is substituted by fluorine or chlorine are 2, 2-difluorovinyl, 3-difluoro-2-propenyl, 4-difluoro-3-butenyl, 5-difluoro-4-pentenyl, or 6, 6-difluoro-5-hexenyl. Further preferable examples for lowering the viscosity are 2, 2-difluorovinyl group or 4, 4-difluoro-3-butenyl group.

Ring A and ring C are 1, 4-cyclohexylene, 1, 4-cyclohexenylene, tetrahydropyran-2, 5-diyl, 1, 4-phenylene in which at least one hydrogen is substituted by fluorine or chlorine, naphthalene-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine, chroman-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine, or chroman-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine. For lowering the lower limit temperature or for raising the upper limit temperature, ring A or ring C is preferably 1, 4-cyclohexylene, and for lowering the lower limit temperature, ring A or ring C is preferably 1, 4-phenylene. Tetrahydropyran-2, 5-diyl as

Or

Preferably, it is

Ring B is 2, 3-difluoro-1, 4-phenylene, 2-chloro-3-fluoro-1, 4-phenylene, 2, 3-difluoro-5-methyl-1, 4-phenylene, 3,4, 5-trifluoronaphthalene-2, 6-diyl, 7, 8-difluorochromane-2, 6-diyl, 3,4,5, 6-tetrafluorofluorene-2, 7-diyl (FLF4), 4, 6-difluorodibenzofuran-3, 7-diyl (DBTF2), 4, 6-difluorodibenzothiophene-3, 7-diyl (DBTF2), or 1,1,6, 7-tetrafluoroindan-2, 5-diyl (InF 4).

The preferred ring B is 2, 3-difluoro-1, 4-phenylene for viscosity reduction and 4, 6-difluorodibenzothiophene-3, 7-diyl for dielectric anisotropy improvement.

And ring D and ring E are 1, 4-cyclohexylene, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, or 2, 5-difluoro-1, 4-phenylene. For increasing the upper temperature limit, the preferred ring D or E is 1, 4-cyclohexylene, and for decreasing the lower temperature limit, the preferred ring D or E is 1, 4-phenylene.

Z¹And Z²Is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy. For lowering the lower limit temperature, Z is preferable¹Or Z²Z is a single bond or ethylene, and is preferably Z for improving dielectric anisotropy¹Or Z²Is a methyleneoxy group. Particularly preferred Z¹Or Z²Is a single bond. Z³Is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy. Preferred Z is Z for improving stability to light or heat³Is a single bond.

a is 1,2, or 3; b is 0 or 1; the sum of a and b is 3 or less. For lowering the lower limit temperature, a is preferably 1, and for raising the upper limit temperature, a is preferably 2 or 3. B is preferably 0 for improving the dielectric anisotropy, and is preferably 1 for lowering the lower limit temperature. c is 1,2, or 3. For lowering the lower limit temperature, c is preferably 1, and for raising the upper limit temperature, c is preferably 2 or 3.

Sixth, a preferred liquid crystalline compound is shown. Preferred compound (1) is the compound (1-1) to the compound (1-35) described in the item 2. Of these compounds, it is preferable that at least one of the first components is the compound (1-1), the compound (1-3), the compound (1-6), the compound (1-8), the compound (1-10), the compound (1-14), or the compound (1-34). Preferably, at least two of the first components are a combination of the compound (1-1) and the compound (1-8), the compound (1-1) and the compound (1-14), the compound (1-3) and the compound (1-8), the compound (1-3) and the compound (1-14), the compound (1-3) and the compound (1-34), the compound (1-6) and the compound (1-8), the compound (1-6) and the compound (1-10), or the compound (1-6) and the compound (1-14).

Preferred compounds (2) are the compounds (2-1) to (2-13) described in the item 5. Of these compounds, at least one of the second components is preferably compound (2-1), compound (2-3), compound (2-5), compound (2-6), compound (2-7), or compound (2-8). Preferably, at least two of the second components are a combination of the compound (2-1) and the compound (2-5), the compound (2-1) and the compound (2-6), the compound (2-1) and the compound (2-7), the compound (2-1) and the compound (2-8), the compound (2-3) and the compound (2-5), the compound (2-3) and the compound (2-6), the compound (2-3) and the compound (2-7), or the compound (2-3) and the compound (2-8).

Seventh, a preferred embodiment of the polymerizable compound and an example thereof will be described. The polymer is derived from a polymerizable compound. The polymerizable compound may be used alone or as a mixture of a plurality of compounds. The preferable polymerizable compound is compound (3), compound (4), or compound (5). The preferable polymerizable compound is compound (6), compound (7), or compound (8). The polymerizable compound may be a mixture of compounds selected from the compounds (3) to (8). The polymerizable compound may also be a mixture with a polymerizable compound other than the compounds (3) to (8). Such a mixture contains a compound selected from the group consisting of the compounds (3) to (8) as a main component. Here, the main component means a component occupying the largest proportion in the mixture. For example, in a mixture of 40 mass% of the compound (3), 30 mass% of the compound (4), and 30 mass% of the compound (5), the main component is the compound (3). When the polymerizable compound used is only the compound (3), the compound (3) is also referred to as a main component.

7-1. Compound (3)

In formula (3), Z⁴Is C1-20 alkylene, wherein at least one hydrogen may be substituted by C1-5 alkyl, fluorine, chlorine, or P³Substituted by at least one-CH₂May be substituted by-O-, -CO-, -COO-, -OCO-, -NH-, or-N (R)⁵) -substituted, at least one-CH₂-CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one-CH₂May be substituted by a divalent group generated by removing two hydrogens from a carbocyclic saturated aliphatic compound, a heterocyclic saturated aliphatic compound, a carbocyclic unsaturated aliphatic compound, a heterocyclic unsaturated aliphatic compound, a carbocyclic aromatic compound, or a heterocyclic aromatic compound, in which the number of carbons is 5 to 35, and at least one hydrogen may be substituted by R⁵Or P³And (4) substitution. Here, R⁵Is an alkyl group having 1 to 12 carbon atoms, in which at least one-CH group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

Examples of the divalent group generated by removing two hydrogens from a carbocyclic or heterocyclic saturated aliphatic compound are 1, 4-cyclohexylene, decahydronaphthalene-2, 6-diyl, tetrahydropyran-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, and the like. Examples of the divalent group generated by removing two hydrogens from a carbocyclic or heterocyclic unsaturated aliphatic compound are 1, 4-cyclohexenylene, dihydropyran-2, 5-diyl, and the like. Examples of the divalent group generated by removing two hydrogens from a carbocyclic or heterocyclic aromatic compound are a 1, 4-phenylene group, a 1, 4-phenylene group in which at least one hydrogen is substituted with fluorine, a 1,2,3, 4-tetrahydronaphthalene-2, 6-diyl group, a naphthalene-1, 2-diyl group, a pyrimidine-2, 5-diyl group, and the like.

Preferred Z⁴Is alkylene group having 1 to 20 carbon atoms, in which at least one hydrogen may be substituted by alkyl group having 1 to 5 carbon atoms, at least one-CH₂-may be substituted by-O-at least one-CH₂May be substituted by a divalent group formed by removing two hydrogens from a carbocyclic saturated aliphatic compound or a carbocyclic aromatic compound, and the number of carbons in these divalent groups is from 5 to 35. Further preferred is Z⁴Is alkylene group having 1 to 20 carbon atoms, in which at least one hydrogen may be substituted by alkyl group having 1 to 5 carbon atoms, at least one-CH₂-may be substituted by-O-.

Preferred Z is Z for improving compatibility with the liquid crystal composition⁴Containing a ring structure such as 1, 4-cyclohexylene or 1, 4-phenylene. For easy formation of the lattice structure, Z is preferred⁴Including chain structures such as alkylene groups.

P¹、P²And P³Is a polymerizable group. Preferred polymerizable groups are represented by the formulae (P-1) to (P-6). Further preferred polymerizable groups are represented by the formulae (P-1) to (P-3). P¹、P²And P³It may also be an acryloyloxy group or a methacryloyloxy group.

In formulae (P-1) to (P-6), M¹、M²And M³Hydrogen, fluorine, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 5 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine. For the purpose of enhancing reactivity, M is preferred¹、M²Or M³Is hydrogen or methyl. Further preferred is M¹Hydrogen or methyl, further preferred M²Or M³Is hydrogen.

Examples of the compound (3) include the compounds (3-1) to (3-3).

In formula (3-1), p is an integer of 1 to 6, and in formula (3-2), q is an integer of 5 to 20.

In the case where the compound (3) has a high polymerizability, the polymer surrounding the droplet becomes strong or the mesh becomes dense due to crosslinking. The polymerizable compound preferably has at least one acryloyloxy group (-OCO-CH ═ CH)₂) Or methacryloxy (-OCO- (CH)₃)C＝CH₂). The compound (3) provides a corresponding polymer by polymerization. When the compound (3) is volatile, an oligomer thereof may be used. The preferred polymer is colorless and transparent, and insoluble in the liquid crystal composition. The preferred polymer has excellent adhesion to the substrate of the element, and reduces the driving voltage. In order to enhance this effect, a polymerizable compound different from the compound (3) may be used in combination.

7-2. Compound (4)

In formula (4), M⁴And M⁵Is hydrogen or methyl. For the purpose of enhancing reactivity, M is preferred⁴Or M⁵Is hydrogen.

Z⁵Is alkylene group having 21 to 80 carbon atoms, in which at least one hydrogen may be substituted by alkyl group having 1 to 20 carbon atoms, fluorine, or chlorine, and at least one-CH₂May be substituted by-O-, -CO-, -COO-, -OCO-, -NH-, or-N (R)⁵) -substituted, at least one-CH₂-CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, where R is⁵Is an alkyl group having 1 to 12 carbon atoms, in which at least one-CH group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-. To achieve low voltage drive, Z is preferred⁵Is alkylene group having 21 to 60 carbon atoms, in which at least one hydrogen may be substituted by alkyl group having 1 to 20 carbon atoms, at least one-CH₂-may be substituted by-O-, -COO-, or-OCO-.

To achieve low voltage driving, Z is further preferable⁵Is an alkylene group in which at least one hydrogen is substituted with an alkyl group. When both hydrogens of the alkylene group are substituted with alkyl groups, steric hindrance is preferably prevented. For example, the two alkyl groups are sufficiently separated, or atIn one alkyl group, an alkyl group having 1 to 5 carbon atoms is used. The same applies when at least three hydrogens are substituted with alkyl groups.

An example of the compound (4) is a compound (4-1).

In the formula (4-1), R⁷And R⁹Is alkyl of 1 to 5 carbon atoms, R⁸And R¹⁰Is an alkyl group having 5 to 20 carbon atoms, at least one-CH group being present in the alkyl group₂May be substituted by-O-, -CO-, -COO-, or-OCO-, Z⁷Is alkylene with 13 to 30 carbon atoms, in which at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

Examples of the compound (4-1) include the compound (4-1-1) and the compound (4-1-2).

In the formulae (4-1-1) and (4-1-2), for example, R⁷And R⁹Is ethyl, R⁸And R¹⁰is-CH₂OCOC₉H₁₉、-CH₂OCOC₁₀H₂₁、-CH₂OC₈H₁₇or-CH₂OC₁₁H₂₃。

The compound (4) is diacrylate or dimethacrylate. Z of formula (4)⁵Being an alkylene group or the like, the polymer easily forms a lattice structure. At Z⁵When the molecular chain of (2) is short, the crosslinked sites of the polymer are close to each other, and therefore the size of the lattice becomes small. At Z⁵When the molecular chain length of (2) is long, the crosslinked portion of the polymer is far away, and the degree of freedom of molecular motion is increased, so that the driving voltage is lowered. At Z⁵In the case of the branched structure, the degree of freedom is further improved, and thus the driving voltage is further reduced. In order to enhance this effect, a polymerizable compound different from the compound (4) may be used in combination.

7-3. Compound (5)

In formula (5), M⁶Is hydrogen or methyl. For the purpose of enhancing reactivity, M is preferred⁶Is hydrogen.

Z⁶Is a single bond or an alkylene group having 1 to 5 carbon atoms, in which alkylene group at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-. Preferred Z⁶Is a single bond or an alkylene group having 1 to 5 carbon atoms, in which at least one-CH group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

R⁶Is an alkyl group having 1 to 40 carbon atoms, in which at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-, at least one-CH₂May be substituted by a divalent group generated by removing two hydrogens from a carbocyclic saturated aliphatic compound, a heterocyclic saturated aliphatic compound, a carbocyclic unsaturated aliphatic compound, a heterocyclic unsaturated aliphatic compound, a carbocyclic aromatic compound, or a heterocyclic aromatic compound, in which the carbon number is 5 to 35, and at least one hydrogen may be substituted by an alkyl group having a carbon number of 1 to 12, in which at least one-CH-group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-. Preferred R⁶Is an alkyl group having a carbon number of 5 to 30. Further preferred is R⁶Is a branched alkyl group having 5 to 30 carbon atoms.

Examples of the compound (5) include compounds (5-1) to (5-6).

In the formulae (5-1) to (5-5), R¹¹Is an alkyl group having 5 to 20 carbon atoms, in which at least one-CH group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-, R¹²And R¹³Is an alkyl group having 3 to 10 carbon atoms, in which at least one-CH group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

The compound (5) is acrylate or methacrylate. R in formula (5)⁶With a ringIn the case of the lamellar structure, the affinity with the liquid crystal composition is improved. At R⁶In the case of alkylene, the polymer easily forms a lattice structure. In the polymer, the degree of freedom of molecular movement is increased by the alkylene group, and thus the driving voltage is decreased. In order to further enhance this effect, a polymerizable compound different from the compound (5) may be used in combination.

7-4. Compound (6) to Compound (8)

In formula (6), formula (7), and formula (8), ring F, ring G, ring I, ring J, ring K, and ring L are 1, 4-cyclohexylene, 1, 4-phenylene, 1, 4-cyclohexenylene, pyridine-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, naphthalene-2, 6-diyl, or fluorene-2, 7-diyl, where at least one hydrogen may be substituted with fluorine, chlorine, cyano, hydroxyl, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkoxycarbonyl group having 1 to 5 carbon atoms, or an alkanoyl group having 1 to 5 carbon atoms. In the formula (6), the formula (7) and the formula (8), preferred rings are 1, 4-cyclohexylene, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2-methyl-1, 4-phenylene, 2-methoxy-1, 4-phenylene or 2-trifluoromethyl-1, 4-phenylene. Further preferred rings are 1, 4-cyclohexylene or 1, 4-phenylene.

Z⁷、Z⁹、Z¹¹、Z¹²And Z¹⁶Is a single bond, -O-, -COO-, -OCO-, or-OCOO-. Z⁸、Z¹⁰、Z¹³And Z¹⁵Is a single bond, -OCH₂-、-CH₂O-、-COO-、-OCO-、-COS-、-SCO-、-OCOO-、-CONH-、-NHCO-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CF₂CF₂-、-CH＝CHCOO-、-OCOCH＝CH-、-CH₂CH₂COO-、-OCOCH₂CH₂-、-CH＝CH-、-N＝CH-、-CH＝N-、-N＝C(CH₃)-、-C(CH₃) N-, -N-, or-C ≡ C-. Z¹⁴Is a single bond, -O-, or-COO-. Among formulae (6) and (7), preferred is Z⁸、Z¹⁰、Z¹³Or Z¹⁵Is a single bond, -OCH₂-、-CH₂O-、-COO-、-OCO-、-CH₂CH₂-、-CH₂CH₂COO-, or-OCOCH₂CH₂-。

X is hydrogen, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, cyano, alkyl having 1 to 20 carbon atoms, alkenyl having 2 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, or alkoxycarbonyl having 1 to 20 carbon atoms.

e and g are integers from 1 to 4; j and l are integers from 0 to 3; the sum of j and l is 1 to 4; d. f, h, i, k, and m are integers from 0 to 20.

M⁷To M¹²Is hydrogen or methyl.

Examples of the compound (6) include the compounds (6-1) to (6-24).

In formulae (6-1) to (6-24), M⁷Is hydrogen or methyl, and d is an integer from 1 to 20.

Examples of the compound (7) include compounds (7-1) to (7-31).

In formulae (7-1) to (7-31), M⁸And M⁹Is hydrogen or methyl, f and h are integers from 1 to 20.

Examples of the compound (8) include compounds (8-1) to (8-10).

In formulae (8-1) to (8-10), M¹⁰、M¹¹And M¹²Is hydrogen or methyl, i, k, and m are integers from 1 to 20.

The compound (6), the compound (7) and the compound (8) have at least one acryloyloxy group (-OCO-CH ═ CH)₂) Or methacryloxy (-OCO- (CH)₃)C＝CH₂). The liquid crystalline compounds have a mesogen (a rigid site exhibiting liquid crystallinity), and these compounds also have a mesogen. Therefore, these compounds are aligned in the same direction together with the liquid crystalline compound by the action of the alignment layer. The orientation is also maintained after polymerization. The liquid crystal composite has high transparency. In order to improve other characteristics, a polymerizable compound different from the compound (6), the compound (7) and the compound (8) may be used in combination.

Eighth, a method for synthesizing the component compound will be explained. These compounds can be synthesized using known methods. A synthesis method is exemplified. The compound (1-1) is synthesized by the method described in Japanese patent laid-open No. Hei 2-503441. The compound (2-1) is synthesized by the method described in Japanese patent laid-open publication No. 59-176221. Antioxidants are already commercially available. The compound (10-1) described later can be obtained from Sigma Aldrich Corporation. The compound (10-2) and the like were synthesized by the method described in the specification of U.S. Pat. No. 3660505. The polymerizable compound may be commercially available or synthesized by a known method.

Compounds not described in the synthesis method can be synthesized by the methods described in the following written description: "Organic Synthesis (Organic Synthesis)" (John Wiley & Sons, Inc.), "Organic reaction (Organic Reactions)" (John Wiley & Sons, Inc.)), "Integrated Organic Synthesis (comparative Organic Synthesis)" (Pergemann Press) "," New Experimental chemistry lecture "(pill-good), and the like. The compositions are prepared by known methods from the compounds obtained in the manner described. For example, the component compounds are mixed and then dissolved in each other by heating.

Ninth, additives that can be added to the polymerizable composition will be described. Such additives include optically active compounds, antioxidants, ultraviolet absorbers, delustering agents, pigments, antifoaming agents, polymerization initiators, polymerization inhibitors, polar compounds, and the like. The additive may be added to the liquid crystal composition, the polymerizable compound, or the mixture thereof without being added to the polymerizable composition.

An optically active compound is added to a liquid crystal composition for the purpose of inducing a helical structure of liquid crystal molecules to impart a twist angle (torsion angle). Examples of such compounds are compound (9-1) to compound (9-5). The preferable proportion of the optically active compound is about 5% by mass or less. Further, the preferable ratio is in the range of about 0.01 to about 2 mass%.

In order to prevent a decrease in specific resistance caused by heating in the atmosphere or to maintain a large voltage holding ratio at room temperature and at a temperature close to the upper limit temperature even after the device is used for a long time, an antioxidant such as the compounds (10-1) to (10-3) may be further added to the composition.

Since the compound (10-2) has low volatility, it is effective for maintaining a large voltage holding ratio not only at room temperature but also at a temperature close to the upper limit temperature after the device is used for a long time. In order to obtain the above effect, the preferable ratio of the antioxidant is about 50ppm or more, and the preferable ratio of the antioxidant is about 600ppm or less so as not to lower the upper limit temperature or not to raise the lower limit temperature. Even more preferred ratios range from about 100ppm to about 300 ppm.

Preferable examples of the ultraviolet absorber are benzophenone derivatives, benzoate derivatives, triazole derivatives and the like. Light stabilizers such as sterically hindered amines are also preferred. Preferable examples of the light stabilizer are compound (11-1) to compound (11-16) and the like. The preferable proportion of these absorbents or stabilizers is about 50ppm or more in order to obtain the above effects, and about 10000ppm or less in order not to lower the upper limit temperature or not to raise the lower limit temperature. Even more preferred ratios range from about 100ppm to about 10000 ppm.

The matting agent is a compound that receives light energy absorbed by the liquid crystalline compound and converts the light energy into thermal energy to prevent decomposition of the liquid crystalline compound. Preferable examples of the matting agent are the compound (12-1) to the compound (12-7) and the like. The preferable proportion of these matting agents is about 50ppm or more in order to obtain the above effects, and about 20000ppm or less in order not to raise the lower limit temperature. Even more preferred ratios range from about 100ppm to about 10000 ppm.

In order to be suitable for a guest-host (GH) mode element, a dichroic dye (dichromatic dye) such as an azo dye or an anthraquinone dye is added to the composition. The preferable ratio of the pigment ranges from about 0.01% by mass to about 10% by mass. In order to prevent foaming, an antifoaming agent such as dimethylsilicone oil or methylphenylsilicone oil is added to the composition. The preferable ratio of the defoaming agent is about 1ppm or more in order to obtain the above effects, and about 1000ppm or less in order to prevent display failure. Even more preferred ratios range from about 1ppm to about 500 ppm.

The polymerizable compound is polymerized by ultraviolet irradiation. The polymerization may be carried out in the presence of a polymerization initiator such as a photopolymerization initiator. The appropriate conditions for carrying out the polymerization, or the appropriate type and amount of initiator, are known to those of ordinary skill in the art to which the invention pertains and are described in the literature. For example, brilliant solid (Irgacure)651 (registered trademark; BASF), brilliant solid (Irgacure)184 (registered trademark; BASF), or Delocur (Darocur)1173 (registered trademark; BASF) as a photopolymerization initiator is suitable for radical polymerization.

When the polymerizable compound is stored, a polymerization inhibitor may be added to prevent polymerization. The polymerizable compound is usually mixed into the liquid crystal composition in a state where the polymerization inhibitor is not removed. Examples of the polymerization inhibitor are hydroquinone, hydroquinone derivatives such as methyl hydroquinone, 4-t-butyl catechol, 4-methoxyphenol, phenothiazine and the like.

The polar compound is an organic compound having polarity. Here, no compound having an ionic bond is contained. Atoms such as oxygen, sulfur, and nitrogen are negatively charged and tend to have a partial negative charge. Carbon and hydrogen are neutral or tend to have a partial positive charge. Polarity arises because part of the charge is distributed unequally among the atoms of different species in the compound. For example, the polar compound has-OH, -COOH, -SH, -NH₂、>NH、>N-, or the like.

The polar group has a non-covalently bonded interaction with the surface of the glass substrate, the metal oxide film, or the like. The compound is adsorbed on the substrate surface by the action of the polar group, and controls the orientation of the liquid crystal molecules. The polar compound may control not only the liquid crystal molecules but also the polymerizable compound. Such an effect is expected for polar compounds.

Finally, the liquid crystal composite or the element will be explained. The method for producing a liquid crystal composite from the polymerizable composition is as follows. First, a polymerizable composition is sandwiched between a pair of substrates. The holding is performed by a vacuum injection method or a liquid crystal dropping method at a temperature higher than the upper limit temperature of the polymerizable composition. In the element manufactured by these methods, display defects such as flow marks and dropping marks may occur. The flow mark is a mark of the flow of the polymerizable composition in the element. The dropping trace is a trace of dropping the polymerizable composition. Such display defects are preferably suppressed. Next, the polymerizable compound is polymerized by heat or light. The polymerization is preferably carried out by irradiating ultraviolet rays. By the polymerization, the polymer phase-separates from the polymerizable composition. Thereby, a light modulation layer is formed between the substrates. The light modulation layer is classified into a polymer dispersion type, a polymer network type, and a mixed existence type of the two.

The device may change with time due to long-term use. The haze ratio may be changed from the initial stage. The change in the haze ratio is preferably small. When the haze change rate is small, a good state of transparency or opacity can be maintained. The haze change rate is preferably 20% or less. Further, the haze change rate is preferably 10% or less or 5% or less.

When the element is used for a long time, flicker (flicker) may occur in a display screen. By inference: the flicker is associated with an afterimage of an image, and is generated by generating a difference between a potential of a positive frame (frame) and a potential of a negative frame when driven with alternating current. The flicker rate (%) can be represented by (| luminance when a positive voltage is applied-luminance when a negative voltage is applied |)/(average luminance) × 100. The flicker rate of the element is preferably in the range of 0% to 1%. The generation of flicker can be suppressed by appropriately selecting the component compounds of the polymerizable composition contained in the element.

When the element is used for a long time, the luminance may be partially lowered. An example of such a display failure is a line afterimage. This is a phenomenon in which the brightness between the electrodes decreases in a stripe shape by repeatedly applying different voltages to the two adjacent electrodes. It is presumed that this phenomenon is caused by accumulation of ionic impurities contained in the liquid crystal composition on the alignment film in the vicinity of the electrode.

Examples of the substrate of the element are glass plates, quartz plates, acrylic plates, and other materials that are not easily deformed. Another example is a flexible transparent plastic film such as an acrylic film or a polycarbonate film. Depending on the application, one of the substrates may be an opaque material such as silicone resin. The substrate has a transparent electrode thereon. An alignment film or the like may be provided over the transparent electrode. Examples of transparent electrodes are Indium Tin Oxide (ITO) or conductive polymers.

As the alignment layer on the substrate, a film of polyimide or polyvinyl alcohol is suitable. For example, the polyimide alignment film can be obtained by coating a polyimide resin composition on a transparent substrate, and thermally hardening at a temperature of 180 ℃ or higher, and if necessary, performing a rubbing treatment by cotton cloth or rayon cloth.

The pair of substrates are opposed to each other so that the transparent electrode layers are positioned inside. Spacers may also be placed in order to make the thickness uniform between the substrates. Examples of spacers are glass particles, plastic particles, alumina particles, photo spacers (photo spacers), etc. The preferred thickness of the light-modulating layer is from about 2 μm to about 50 μm, and more preferably from about 5 μm to about 20 μm. When a pair of substrates is bonded, a general-purpose sealant can be used. An example of the sealant is an epoxy thermosetting composition.

In such an element, a light absorbing layer, a diffusion reflection plate, and the like may be disposed on the back surface of the element as necessary. The functions of mirror reflection, diffuse reflection, regressive reflection, holographic reflection and the like can also be added.

Such an element functions as a light control film or a light control glass. When the element is in the form of a film, the element can be attached to an existing window or can be sandwiched between a pair of glass plates to form a laminated glass. Such elements are used for windows or partitions of conference rooms and corridors arranged on the outside walls. That is, there are applications such as electronic blinds (electronic blinds), light-adjusting windows, and smart windows. Further, the function as an optical switch can be applied to a liquid crystal shutter or the like.

Examples

The present invention will be further described in detail by way of examples. The present invention is not limited by these examples. The present invention comprises mixtures of composition (M1) and composition (M2). The invention also includes mixtures of at least two of the compositions of the examples. The synthesized compound is identified by Nuclear Magnetic Resonance (NMR) analysis or the like. The properties of the compounds, compositions and devices were measured by the following methods.

NMR analysis: DRX-500 manufactured by Bruker BioSpin was used for the measurement.¹In the measurement of H-NMR, a sample was dissolved in CDCl₃The measurement was performed at room temperature under the conditions of 500MHz and 16 cumulative times in the deuterated solvent. Tetramethylsilane was used as an internal standard. In that¹⁹In the measurement of F-NMR, CFCl was used₃As an internal standard, measurement was performed 24 times in cumulative number. In the description of the nuclear magnetic resonance spectrum, s means a singlet, d means a doublet, t means a triplet, q means a quartet, quin means a quintet, sex means a sextuple, m means a multiplet, br means a broad peak.

Gas chromatographic analysis: for measurement, a GC-14B gas chromatograph manufactured by Shimadzu corporation was used. The carrier gas was helium (2 mL/min). The sample vaporizer was set at 280 ℃ and the detector (flame ionization detector, FID) was set at 300 ℃. For separation of component compounds, a capillary column DB-1 (length 30m, inner diameter 0.32mm, film thickness 0.25 μm; fixing liquid phase is dimethylpolysiloxane; non-polar) manufactured by Agilent Technologies Inc. was used. After the column was held at 200 ℃ for 2 minutes, the temperature was raised to 280 ℃ at a rate of 5 ℃/min. After preparing the sample into an acetone solution (0.1 mass%), 1. mu.L of the acetone solution was injected into the sample vaporization chamber. The record is a chromatograph module (Chromatopac) model C-R5A manufactured by Shimadzu corporation or an equivalent thereof. The obtained gas chromatogram showed the retention time of the peak and the area of the peak corresponding to the component compound.

As a solvent for diluting the sample, chloroform, hexane, etc. can be used. To separate the constituent compounds, the following capillary column may be used. HP-1 (length 30m, inner diameter 0.32mm, film thickness 0.25 μm) manufactured by Agilent technologies, Inc., Rtx-1 (length 30m, inner diameter 0.32mm, film thickness 0.25 μm) manufactured by Restek Corporation, and BP-1 (length 30m, inner diameter 0.32mm, film thickness 0.25 μm) manufactured by Australian SGE International Pty.Ltd. For the purpose of preventing overlapping of compound peaks, capillary columns manufactured by Shimadzu corporation CBP1-M50-025 (length 50M, inner diameter 0.25mm, film thickness 0.25 μ M) were used.

The ratio of the liquid crystalline compound contained in the composition can be calculated by the following method. The mixture of liquid crystalline compounds was analyzed by gas chromatography (FID). The area ratio of the peaks in the gas chromatogram corresponds to the ratio of the liquid crystalline compound. When the capillary column described above is used, the correction coefficient of each liquid crystalline compound can be regarded as 1. Therefore, the ratio (% by mass) of the liquid crystalline compound can be calculated from the area ratio of the peak.

Measurement of the sample: in determining the properties of the composition or of the element comprising said composition, the composition is used directly as a sample. In order to measure the characteristics of the compound, a sample for measurement was prepared by mixing the compound (15 mass%) in a mother liquid crystal (85 mass%). From the values obtained by the measurement, the characteristic values of the compounds were calculated by extrapolation. (extrapolated value) { (measured value of sample) — 0.85 × (measured value of mother liquid crystal) }/0.15. When a smectic phase (or crystal) precipitates at 25 ℃ in this ratio, the ratio of the compound to the mother liquid crystal is set to 10% by mass: 90% by mass and 5% by mass: 95% by mass and 1% by mass: the order of 99 mass% was changed. The values of the upper limit temperature, optical anisotropy, viscosity, and dielectric anisotropy relating to the compound were obtained by the extrapolation method.

The following mother liquid crystal was used. The proportion of the component compounds is represented by mass%.

The determination method comprises the following steps: the characteristics were measured by the following methods. These methods are mostly described in JEITA standard (JEITA. ED-2521B) examined and established by the society of electronic Information Technology Industries (Japan Electronics and Information Technology Industries Association; referred to as JEITA), or modified. In a Twisted Nematic (TN) cell used for measurement, a Thin Film Transistor (TFT) is not mounted.

(1) Upper limit temperature of nematic phase (NI;. degree. C.): the sample was placed on a hot plate of a melting point measuring apparatus equipped with a polarizing microscope, and heated at a rate of 1 ℃/min. The temperature at which a portion of the sample changes from nematic to isotropic liquid is measured. The upper limit temperature of the nematic phase may be simply referred to as "upper limit temperature".

(2) Lower limit temperature (T) of nematic phase_C(ii) a C): the nematic phase was observed after placing the sample in a glass bottle and keeping the bottle in a freezer at 0 ℃, -10 ℃, -20 ℃, -30 ℃ and-40 ℃ for 10 days. For example, when the sample is kept in a nematic phase at-20 ℃ and changed to a crystalline or smectic phase at-30 ℃, T is set_CIs reported as < -20 ℃. The lower limit temperature of the nematic phase may be simply referred to as "lower limit temperature".

(3) Viscosity (. eta.; measured at 20 ℃ C.; mPas): for the measurement, an E-type rotational viscometer manufactured by tokyo counter gmbh was used.

(4) Viscosity (rotational viscosity; γ 1; measured at 25 ℃; mPas): for the measurement, a rotational viscosity ratio measuring system LCM-2 of Toyang Technica (Toyo technical) Co., Ltd. was used. The sample was injected into a Vertical Alignment (VA) cell having a spacing (cell gap) of 10 μm between two glass substrates. A rectangular wave (55V, 1ms) was applied to the element. The peak current (peak current) and peak time (peak time) of the transient current (transient current) generated by this application are measured. These measured values and the dielectric anisotropy were used to obtain values of rotational viscosity. The dielectric anisotropy was measured by the method described in measurement (6).

(5) Optical anisotropy (refractive index anisotropy; Δ n; measured at 25 ℃): the measurement was performed using a light having a wavelength of 589nm by an Abbe refractometer having a polarizing plate attached to an eyepiece lens. After rubbing the surface of the main prism in one direction, the sample was dropped on the main prism. The refractive index n/is measured when the direction of polarization is parallel to the direction of rubbing. The refractive index n ″) is measured when the direction of the polarized light is perpendicular to the direction of the friction. The value of the optical anisotropy is calculated from the formula Δ n ═ n/n ″.

(6) Dielectric anisotropy (. DELTA.. di-elect cons.; measured at 25 ℃): the value of the dielectric anisotropy is calculated according to the formula Δ ∈/∈ j. The dielectric constants (. epsilon./. epsilon. mu.j) were measured in the following manner.

1) Measurement of dielectric constant (. epsilon. /): a solution of octadecyltriethoxysilane (0.16mL) in ethanol (20mL) was coated on the well-cleaned glass substrate. The glass substrate was rotated by a rotator and then heated at 150 ℃ for 1 hour. A VA device having a gap (cell gap) of 4 μm between two glass substrates was put in a sample, and the device was sealed with an adhesive cured by ultraviolet rays. A sine wave (0.5V, 1kHz) was applied to the cell, and the dielectric constant (. epsilon. /) in the long axis direction of the liquid crystal molecules was measured after 2 seconds.

2) Measurement of dielectric constant (. epsilon. DELTA. -): the polyimide solution was coated on the well-cleaned glass substrate. After the glass substrate is fired, the obtained alignment film is subjected to rubbing treatment. A sample was placed in a TN cell having a cell gap of 9 μm and a twist angle of 80 degrees between two glass substrates. Sine wave (0.5V, 1kHz) was applied to the element, and the dielectric constant (∈ ∈ in the short axis direction of the liquid crystal molecules was measured after 2 seconds.

(7) Threshold voltage (Vth; measured at 25 ℃; V): for measurement, a luminance meter model LCD5100 manufactured by tsukamur electronics gmbh was used. The light source is a halogen lamp. A sample was placed in a VA element of a normally black mode (normal black mode) in which the gap between two glass substrates (cell gap) was 4 μm and the rubbing directions were antiparallel, and the element was sealed with an adhesive cured by ultraviolet light. The voltage applied to the element (60Hz, rectangular wave) was increased stepwise from 0V to 20V in units of 0.02V. At this time, the element was irradiated with light from the vertical direction, and the amount of light transmitted through the element was measured. A voltage-transmittance curve was prepared in which the transmittance was 100% when the light amount reached the maximum and the transmittance was 0% when the light amount was the minimum. The threshold voltage is represented by a voltage at which the transmittance becomes 10%.

(8) Voltage holding ratio (VHR; measured at 25;%): the TN element used for the measurement had a polyimide alignment film and the gap (cell gap) between the two glass substrates was 3.5 μm. The TN cell was injected with a sample, and sealed with an adhesive cured by ultraviolet light. The TN element was placed in a thermostatic bath at 60 ℃ and charged by applying a pulse voltage (1V, 60. mu.s, 3 Hz). The decayed voltage was measured by a high-speed voltmeter for 166.6 milliseconds, and the area a between the voltage curve and the horizontal axis in the unit cycle was determined. The area B is the area when not attenuated. The voltage holding ratio is expressed by a percentage of the area a to the area B.

(9) Voltage holding ratio (UV-VHR; measured at 25;%): the TN cell into which the sample was injected was irradiated with 5 mw ultraviolet light for 166.6 minutes using black light (black light) as a light source. The voltage holding ratio was measured to evaluate the stability to ultraviolet light. The constitution of the TN element and the method for measuring the voltage holding ratio are described in the item (8). Compositions with large UV-VHRs have a large stability to UV light. The UV-VHR is preferably 90% or more, more preferably 95% or more.

(10) Voltage holding ratio (heated VHR; measured at 25;%): the TN cells impregnated with the samples were heated in a thermostatic bath at 120 ℃ for 20 hours, and then the voltage holding ratio was measured to evaluate the stability to heat. The constitution of the TN element and the method for measuring the voltage holding ratio are described in the item (8). Compositions with large heated VHRs have a large stability to heat. The heating VHR is preferably 90% or more, and more preferably 95% or more.

(11) Response time (. tau.; measured at 25 ℃ C.; ms): for measurement, a luminance meter model LCD5100 manufactured by tsukamur electronics gmbh was used. The light source is a halogen lamp. The Low-pass filter (Low-pass filter) is set to 5 kHz. A sample was placed in a VA element of a normally black mode (normal black mode) in which the gap between two glass substrates (cell gap) was 4 μm and the rubbing directions were antiparallel. The element is sealed using an adhesive cured with ultraviolet rays. A square wave (60Hz, 10V, 0.5 sec) was applied to the element. At this time, the element was irradiated with light from the vertical direction, and the amount of light transmitted through the element was measured. The transmittance was regarded as 100% when the light amount reached the maximum, and 0% when the light amount was the minimum. The response time is represented by the time (fall time; millisecond) required for the transmittance to change from 90% to 10%.

(12) Elastic constant (K11: splay (splay) elastic constant, K33: bend (bend) elastic constant; measured at 25 ℃; pN): for the measurement, an EC-1 elastic constant measuring instrument manufactured by Toyang Technica (Toyo technical) Co., Ltd was used. A VA device having a gap (cell gap) of 20 μm between two glass substrates was used as a sample. A charge of 20V to 0V was applied to the element, and the electrostatic capacitance and the applied voltage were measured. The value of the elastic constant was obtained from the equation (2.100) by fitting the measured electrostatic capacitance (C) to the value of the applied voltage (V) using the equations (2.98) and (2.101) on page 75 of the handbook of liquid crystal devices (journal industries, press).

(13) Specific resistance (. rho.; measured at 25 ℃ C.;. omega. cm): 1.0mL of the sample was placed in a container equipped with an electrode. A DC voltage (10V) was applied to the vessel, and a DC current after 10 seconds was measured. The specific resistance is calculated by the following equation. (specific resistance) { (voltage) × (capacitance of container) }/{ (direct current) × (dielectric constant of vacuum) }

(14) Pretilt angle (degrees): an spectroscopic ellipsometer M-2000U (manufactured by j.a. woollam co., Inc.) was used for measurement of the pretilt angle.

(15) Alignment stability (liquid crystal alignment axis stability): changes in the liquid crystal alignment axis on the electrode side of a Fringe Field Switching (FFS) element were evaluated. The liquid crystal alignment angle phi (before) on the electrode side before applying stress was measured. After applying a square wave of 4.5V and 60Hz for 20 minutes to the element, the cell was buffered for 1 second, and the liquid crystal alignment angle φ (hereinafter) on the electrode side was measured again after 1 second and 5 minutes. From these values, the change Δ Φ (deg.) of the liquid crystal alignment angle after 1 second and 5 minutes was calculated using the following equation. Δ φ (deg.) φ (after) - φ (before)

These measurements are carried out with reference to "Solid Films" (Thin Solid Films) ", 455-456, (2004) -596-600 of J.Hilfekf (J.Hilfaker), B.Jones (B.John), C.Herzinger (C.Herzinger), J.F.Elman (J.F.Elman), E.Monbacil (E.Montbach), D.Bryant (D.Bryant) and P.J.Bos (P.J.Bos). It can be said that the smaller the change (Δ Φ), the smaller the rate of change of the liquid crystal alignment axis, and the more stable the liquid crystal molecules.

(16) Scintillation rate (measured at 25;%): a multimedia display tester (3298F) manufactured by york motor (gang) was used for the measurement. The Light source is a Light Emitting Diode (LED). A sample was placed in an element of a normally black mode (normal black mode) in which the gap between two glass substrates (cell gap) was 3.5 μm and the rubbing directions were antiparallel. The element is sealed using an adhesive that is cured by ultraviolet rays. A voltage is applied to the element, and the voltage at which the amount of light transmitted through the element reaches the maximum is measured. The sensor section is brought close to the element while the voltage is applied to the element, and the displayed flicker rate is read. The flicker rate is preferably small.

(17) Line afterimage (Line Image learning Parameter; LISP;%): line afterimages are generated by applying electrical stress to the elements. The luminance of the region where the line afterimage exists and the luminance of the remaining region (reference region) are measured. The ratio of the reduction in luminance due to the line afterimage is calculated, and the size of the line afterimage is represented by this ratio.

17a) Measurement of luminance: an image of the element was taken using an imaging color luminance meter (PM-1433F-0, manufactured by radial Zemax). The image was analyzed by software (Prometric 9.1, manufactured by radial Imaging) to calculate the brightness of each region of the element. Average luminance of 3500cd/m used in light source²The LED backlight of (1).

17b) Setting of stress voltage: a sample was placed in an FFS cell (16 cells of 4 cells in the vertical direction × 4 cells in the horizontal direction) having a cell gap of 3.5 μm and a matrix structure, and the cell was sealed with an adhesive cured by ultraviolet light. Polarizing plates are disposed on the upper and lower surfaces of the element so that the polarizing axes are orthogonal to each other. Light was irradiated to the element and a voltage (rectangular wave, 60Hz) was applied. The voltage was in the range of 0V to 7.5V, and the luminance of the transmitted light at each voltage was measured while increasing stepwise in units of 0.1V. The voltage at which the luminance reaches the maximum is simply referred to as V255. The voltage at which the luminance reaches 21.6% of V255 (i.e., 127 gradations) is simply referred to as V127.

17c) Conditions of stress: v255 (square wave, 30Hz) was applied to the stress region and 0.5V (square wave, 30Hz) was applied to the reference region at 60 ℃ for 23 hours, and a checkerboard pattern was displayed. Next, V127 (square wave, 0.25Hz) was applied, and the brightness was measured under the condition of an exposure time of 4000 milliseconds.

17d) Calculation of line afterimage: for the calculation, 4 units (vertical 2 units × horizontal 2 units) in the center of 16 units were used. The 4 units were divided into 25 regions (vertical 5 units × horizontal 5 units). The average luminance of four regions (vertical 2 cells × horizontal 2 cells) located at four corners is simply referred to as luminance a. The area formed by removing the four corner areas from the 25 areas is a cross. Of the four regions obtained by removing the central intersection region from the cross-shaped region, the minimum value of the luminance is simply referred to as luminance B. The line residual image is calculated according to the following equation. (line afterimage) (luminance a-luminance B)/luminance a × 100. The line afterimage is preferably small.

(18) Face Image learning Parameter (FISP)%): the surface residual image is generated by applying an electrical stress to the element. The luminance of the region where the surface afterimage exists and the luminance of the remaining region were measured at 25 ℃. The ratio of the luminance change due to the surface afterimage is calculated, and the size of the surface afterimage is represented by this ratio. 18a) The "measurement of luminance", "setting of stress voltage", and "condition of stress" are in the order described in the item "line afterimage".

18b) The surface residual image is calculated according to the following expression. (surface afterimage) (luminance C-luminance D)/luminance D × 100. Here, the luminance C is an average luminance of 8 cells to which V255 is applied out of 16 cells, and the luminance D is an average luminance of 8 cells to which 0.5V is applied. The surface afterimage is preferably small. When the dielectric anisotropy of the liquid crystal composition is positive, the surface residual image is represented by P-FISP. When negative, the surface residual image is expressed by N-FISP.

(19) Haze ratio (%): a haze meter NDH5000 (manufactured by japan electro-chromatic industries, ltd.) was used to measure the haze ratio.

(20) The haze change rate (%). A weather resistance test of the element was conducted. The haze was measured before and after the test, and the haze change rate was calculated. This test was carried out in accordance with Japanese Industrial Standards (JIS) K5600-7-7, weather resistance-promoting property and light resistance-promoting property (xenon lamp method). The measurement conditions were illuminance (UVA; 180W/m)²) The irradiation time (100 hours), the blackboard temperature (63 ℃ C. + -. 2 ℃ C.), the in-tank temperature (35 ℃ C.), and the in-tank relative humidity (40% RH).

Examples of the composition are shown below. The liquid crystalline compound is represented by a symbol based on the definition in table 3 below. In Table 3, the configuration of the 1, 4-cyclohexylene group-related stereo-configuration is trans. The numbers in parentheses following the marked compounds indicate the chemical formula to which the compound belongs. The symbol (-) indicates other liquid crystalline compounds. The ratio (percentage) of the liquid crystalline compound is a mass percentage (mass%) based on the mass of the liquid crystal composition containing no additive. Finally, the values of the properties of the composition are summarized.

TABLE 3 expression of Compounds Using symbols

R-(A₁)-Z₁-·····-Z_n-(A_n)-R’

[ composition (M1) ]

NI＝103.4℃；Tc<-20℃；η＝26.9mPa·s；Δn＝0.107；Δε＝-3.6；Vth＝2.45V；γ1＝181.8mPa·s.

[ composition (M2) ]

NI＝100.7℃；Tc<-20℃；η＝34.3mPa·s；Δn＝0.153；Δε＝-4.6；Vth＝2.23V；γ1＝248.2mPa·s.

[ composition (M3) ]

NI＝92.2℃；Tc<-20℃；η＝41.8mPa·s；Δn＝0.195；Δε＝-3.2；Vth＝2.61V；γ1＝194.0mPa·s.

[ composition (M4) ]

NI＝101.7℃；Tc<-20℃；η＝26.1mPa·s；Δn＝0.102；Δε＝-3.5；Vth＝2.46V；γ1＝174.0mPa·s.

[ composition (M5) ]

NI＝100.8℃；Tc<-20℃；η＝32.9mPa·s；Δn＝0.150；Δε＝-4.5；Vth＝2.29V；γ1＝240.3mPa·s.

[ composition (M6) ]

NI＝95.6℃；Tc<-20℃；η＝41.2mPa·s；Δn＝0.200；Δε＝-3.0；Vth＝2.73V；γ1＝192.4mPa·s.

[ composition (M7) ]

NI＝105.9℃；Tc<-20℃；η＝29.9mPa·s；Δn＝0.143；Δε＝-3.6；Vth＝2.58V；γ1＝226.9mPa·s.

[ composition (M8) ]

NI＝100.7℃；Tc<-20℃；η＝42.4mPa·s；Δn＝0.200；Δε＝-3.1；Vth＝2.75V；γ1＝281.2mPa·s.

[ composition (M9) ]

NI＝97.8℃；Tc<-20℃；η＝29.2mPa·s；Δn＝0.150；Δε＝-3.8；Vth＝2.46V；γ1＝217.0mPa·s.

[ composition (M10) ]

NI＝82.5℃；Tc<-20℃；η＝21.3mPa·s；Δn＝0.117；Δε＝-4.1；Vth＝2.08V；γ1＝130.1mPa·s.

[ composition (M11) ]

NI＝87.6℃；Tc<-20℃；Δn＝0.126；Δε＝-4.5；η＝25.3mPa·s.

[ composition (M12) ]

NI＝81.2℃；Tc<-20℃；Δn＝0.107；Δε＝-3.2；η＝15.5mPa·s.

[ composition (M13) ]

NI＝88.2℃；Tc<-20℃；Δn＝0.115；Δε＝-2.1；η＝18.3mPa·s.

[ composition (M14) ]

NI＝89.9℃；Tc<-20℃；Δn＝0.122；Δε＝-4.2；η＝23.4mPa·s.

[ composition (M15) ]

NI＝77.1℃；Tc<-20℃；Δn＝0.101；Δε＝-3.0；η＝13.9mPa·s.

[ composition (M16) ]

NI＝93.0℃；Tc<-20℃；Δn＝0.124；Δε＝-4.5；η＝25.0mPa·s.

[ composition (M17) ]

NI＝87.5℃；Tc<-20℃；Δn＝0.100；Δε＝-3.4；η＝18.9mPa·s.

[ composition (M18) ]

NI＝76.4℃；Tc<-20℃；Δn＝0.104；Δε＝-3.2；η＝15.6mPa·s.

[ composition (M19) ]

NI＝78.3℃；Tc<-20℃；Δn＝0.103；Δε＝-3.2；η＝17.7mPa·s.

[ composition (M20) ]

NI＝75.9℃；Tc<-20℃；Δn＝0.114；Δε＝-3.9；η＝24.7mPa·s.

[ composition (M21) ]

NI＝72.6℃；Tc<-20℃；Δn＝0.105；Δε＝-2.5；η＝15.7mPa·s.

[ composition (M22) ]

NI＝82.8℃；Tc<-20℃；Δn＝0.118；Δε＝-4.4；η＝22.5mPa·s.

[ composition (M23) ]

NI＝78.1℃；Tc<-20℃；Δn＝0.107；Δε＝-3.2；η＝15.9mPa·s.

[ composition (M24) ]

NI＝88.5℃；Tc<-20℃；Δn＝0.108；Δε＝-3.8；η＝24.6mPa·s.

[ composition (M25) ]

NI＝71.8℃；Tc<-20℃；Δn＝0.103；Δε＝-2.5；η＝14.2mPa·s.

[ composition (M26) ]

NI＝98.8℃；Tc<-20℃；Δn＝0.111；Δε＝-3.2；η＝23.9mPa·s.

[ composition (M27) ]

NI＝77.5℃；Tc<-20℃；Δn＝0.084；Δε＝-2.6；η＝22.8mPa·s.

[ composition (M28) ]

NI＝70.6℃；Tc<-20℃；Δn＝0.129；Δε＝-4.3；η＝27.0mPa·s.

[ composition (M29) ]

NI＝73.5℃；Tc<-20℃；Δn＝0.106；Δε＝-2.7；η＝17.0mPa·s.

[ composition (M30) ]

NI＝86.0℃；Tc<-20℃；Δn＝0.110；Δε＝-3.8；η＝22.9mPa·s.

The polymerizable compound (RM-1) to the polymerizable compound (RM-11) used in the examples are shown below.

[ example 1]

Production of liquid Crystal light-adjusting element-1

The composition (M1) had negative dielectric anisotropy. A polymerizable composition was prepared by mixing 95% by mass of the composition (M1) and 5% by mass of the polymerizable compound (RM-1). 0.3% by mass of Irgacure 651 (photopolymerization initiator; BASF) was added based on the polymerizable compound. The polymerizable composition was injected into a Vertical Alignment (VA) cell having a spacing (cell gap) of 3.5 μm between two glass substrates. The temperature at the time of injection was 140 ℃. The element was irradiated with 1J of 365nm ultraviolet light to produce an element having a liquid crystal composite. The element is transparent. When a voltage of 45V was applied to the element, the element became opaque when irradiated with light. From this result, the VA element is in the reverse mode.

[ example 2 to example 30]

Using the compositions (M2) to (M30), the polymerizable compounds (RM-1) to (RM-9) and the brilliant good solid (Irgacure)651, VA devices were produced in the same order as in example 1. The results are summarized in Table 4. The VA elements are all in reverse mode.

TABLE 4 fabrication of liquid crystal dimming elements

[ example 31]

Production of liquid Crystal light-adjusting element-2

Next, the two polymerizable compositions are combined. A polymerizable composition was prepared by mixing 90 mass% of the composition (M1) with 5 mass% of the polymerizable compound (RM-8) and 5 mass% of the polymerizable compound (RM-11). 0.3% by mass of Irgacure 651 (photopolymerization initiator; BASF) was added based on the polymerizable compound. The polymerizable composition was injected into a VA device having a spacing (cell gap) of 3.5 μm between two glass substrates. The temperature at the time of injection was 140 ℃. The element was irradiated with 1J of 365nm ultraviolet light to produce an element having a liquid crystal composite. The element is transparent. When a voltage of 45V was applied to the element, the element became opaque when irradiated with light. From this result, the VA element is in the reverse mode.

[ examples 32 to 40]

A VA device was produced in the same manner as in example 31 using the composition (M1), two polymerizable compounds and Irgacure 651. The results are summarized in Table 5. The VA elements are all in reverse mode.

TABLE 5 fabrication of liquid crystal dimming elements

Rate of change of haze

The VA elements fabricated in examples 1 to 9 were disposed in the haze meter such that the elements were perpendicular to the incident light. The haze ratio was measured by applying a voltage ranging from 0V to 60V to the element. Then, the haze ratio after the weather resistance test performed under the conditions described in the measurement method (20) was measured to obtain the haze change ratio. The results are summarized in Table 6.

TABLE 6 measurement of haze Change ratio

Liquid crystal light modulation element	Haze Change Rate (%)
		VA component of example 1	8.8
VA component of example 2	7.5
		VA component of example 3	4.4
VA component of example 4	6.9
		VA component of example 5	6.8
VA component of example 6	8.5
		VA component of example 7	9.4
VA component of example 8	8.1
		VA component of example 9	8.8

As is apparent from the results in tables 4 and 5, the liquid crystal composites of examples 1 to 40 have characteristics suitable for the liquid crystal dimming element of the reverse mode. Table 6 shows the results of the weather resistance test described in JIS. The haze change rate is in the range of 4.4% to 9.4%. All of them are 20% or less. From this result, it is understood that the temporal change of the liquid crystal dimming element is small.

In the measurement of the characteristics of a liquid crystal composition or a liquid crystal display device containing the composition, a device having a glass substrate is generally used. On the other hand, a plastic film may be used as a substrate in a liquid crystal light control element. Therefore, a polycarbonate substrate was prepared, and characteristics such as threshold voltage and response time were measured. This measured value was compared with the case of the element of the glass substrate. As a result, the measured values of both types were almost the same. Therefore, the characteristics such as the threshold voltage and the response time are values measured by an element of the glass substrate.

Industrial applicability

The liquid crystal light control element containing the liquid crystal composite of the present invention has characteristics such as short response time, large voltage holding ratio, low threshold voltage, large haze ratio, high weather resistance, and long life, and is therefore useful for light control windows, smart windows, and the like.

Claims

1. A liquid crystal light control element having a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from compounds represented by the formula (1) as a first component and a polymer, wherein the liquid crystal light control element has an illuminance of 180W/m²And a haze change rate of 20% or less before and after a weather resistance test conducted under conditions in which the irradiation time is 100 hours and the in-cell temperature is 35 ℃.

In the formula (1), R¹And R²Is hydrogen, alkyl group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, carbon atomAn alkenyl group having 2 to 12 carbon atoms, an alkenyloxy group having 2 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine; ring A and ring C are 1, 4-cyclohexylene, 1, 4-cyclohexenylene, tetrahydropyran-2, 5-diyl, 1, 4-phenylene in which at least one hydrogen is substituted by fluorine or chlorine, naphthalene-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine, chroman-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine, or chroman-2, 6-diyl in which at least one hydrogen is substituted by fluorine or chlorine; ring B is 2, 3-difluoro-1, 4-phenylene, 2-chloro-3-fluoro-1, 4-phenylene, 2, 3-difluoro-5-methyl-1, 4-phenylene, 3,4, 5-trifluoronaphthalene-2, 6-diyl, 7, 8-difluorochromane-2, 6-diyl, 3,4,5, 6-tetrafluorofluorene-2, 7-diyl, 4, 6-difluorodibenzofuran-3, 7-diyl, 4, 6-difluorodibenzothiophene-3, 7-diyl, or 1,1,6, 7-tetrafluoroindan-2, 5-diyl; z¹And Z²Is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy; a is 0, 1,2, or 3, b is 0 or 1; and the sum of a and b is 3 or less.

2. The liquid crystal dimming element according to claim 1, which has a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from the group consisting of compounds represented by formulae (1-1) to (1-35) as a first component and a polymer.

In the formulae (1-1) to (1-35), R¹And R²Is hydrogen, alkyl group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, alkenyl group having 2 to 12 carbon atoms, alkenyloxy group having 2 to 12 carbon atoms, or alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine.

3. The liquid crystal dimming element according to claim 1 or 2, wherein the proportion of the first component is in a range of 20 to 90 mass% based on the mass of the liquid crystal composition.

4. The liquid crystal dimming element according to any one of claims 1 to 3, which has a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from the compounds represented by formula (2) as a second component and a polymer.

5. The liquid crystal dimming element according to any one of claims 1 to 4, which has a liquid crystal composite comprising a liquid crystal composition containing at least one compound selected from compounds represented by formulae (2-1) to (2-13) as a second component and a polymer.

In the formulae (2-1) to (2-13), R³And R⁴Is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms wherein at least one hydrogen is substituted with fluorine or chlorine, or an alkenyl group having 2 to 12 carbon atoms wherein at least one hydrogen is substituted with fluorine or chlorine.

6. The liquid crystal dimming element according to claim 4 or 5, wherein the proportion of the second component is in a range of 10 to 80 mass% based on the mass of the liquid crystal composition.

7. The liquid crystal light-modulating element according to any one of claims 1 to 6, wherein the polymer is a polymer derived from a mixture of polymerizable compounds containing a compound represented by formula (3) as a main component.

P¹-Z⁴-P² (3)

8. The liquid crystal dimming element according to claim 7, wherein P¹、P²And P³Is a group selected from the polymerizable groups represented by the formulae (P-1) to (P-6).

9. The liquid crystal dimming element according to claim 7, wherein P¹、P²And P³Is an acryloyloxy group or a methacryloyloxy group.

10. The liquid crystal light-modulating element according to any one of claims 1 to 6, wherein the polymer is a polymer derived from a mixture of polymerizable compounds containing a compound represented by formula (4) as a main component.

11. The liquid crystal light-modulating element according to any one of claims 1 to 6, wherein the polymer is a polymer derived from a mixture of polymerizable compounds containing a compound represented by formula (5) as a main component.

In formula (5), M⁶Is hydrogen or methyl; z⁶Is a single bond or an alkylene group having 1 to 5 carbon atoms, in which alkylene group at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-; r⁶Is an alkyl group having 1 to 40 carbon atoms, in which at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-, at least one-CH₂May be substituted by a divalent group generated by removing two hydrogens from a carbocyclic saturated aliphatic compound, a heterocyclic saturated aliphatic compound, a carbocyclic unsaturated aliphatic compound, a heterocyclic unsaturated aliphatic compound, a carbocyclic aromatic compound, or a heterocyclic aromatic compound, in which the carbon number is 5 to 35, and at least one hydrogen may be substituted by an alkyl group having a carbon number of 1 to 12, in which at least one-CH-group₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

12. The liquid crystal dimming element according to claim 11, wherein in formula (5), M⁶Is hydrogen or methyl; z⁶Is a single bond or an alkylene group having 1 to 5 carbon atoms, in which alkylene group at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-; r⁶Is an alkyl group having 1 to 40 carbon atoms, in which at least one hydrogen may be substituted by fluorine or chlorine, at least one-CH₂-may be substituted by-O-, -CO-, -COO-, or-OCO-.

13. The liquid crystal light-modulating element according to any one of claims 1 to 6, wherein the polymer is a polymer derived from a mixture of polymerizable compounds containing a compound selected from the group consisting of compounds represented by formula (6), formula (7), and formula (8) as a main component.

In formula (6), formula (7), and formula (8), ring F, ring G, ring I, ring J, ring K, and ring L are 1, 4-cyclohexylene, 1, 4-phenylene, 1, 4-cyclohexenylene, pyridine-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, naphthalene-2, 6-diyl, or fluorene-2, 7-diyl, where at least one hydrogen may be substituted with fluorine, chlorine, cyano, hydroxyl, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkoxycarbonyl group having 1 to 5 carbon atoms, or an alkanoyl group having 1 to 5 carbon atoms; z⁷、Z⁹、Z¹¹、Z¹²And Z¹⁶Is a single bond, -O-, -COO-, -OCO-, or-OCOO-; z⁸、Z¹⁰、Z¹³And Z¹⁵Is a single bond, -OCH₂-、-CH₂O-、-COO-、-OCO-、-COS-、-SCO-、-OCOO-、-CONH-、-NHCO-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CF₂CF₂-、-CH＝CHCOO-、-OCOCH＝CH-、-CH₂CH₂COO-、-OCOCH₂CH₂-、-CH＝CH-、-N＝CH-、-CH＝N-、-N＝C(CH₃)-、-C(CH₃) -N-, -N-, or-C ≡ C-; z¹⁴Is a single bond, -O-or-COO-; x is hydrogen, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, cyano, alkyl of carbon number 1 to 20, alkenyl of carbon number 2 to 20, alkoxy of carbon number 1 to 20, or alkoxycarbonyl of carbon number 1 to 20; e and g are integers from 1 to 4; j and l are integers from 0 to 3; the sum of j and l is 1 to 4; d. f, h, i, k, and m are integers from 0 to 20; m⁷To M¹²Is hydrogen or methyl.

14. The liquid crystal dimming element according to any one of claims 1 to 13, wherein the ratio of the liquid crystal composition is in a range of 50 to 95% by mass and the ratio of the polymer is in a range of 5 to 50% by mass based on the mass of the liquid crystal composite.

15. The liquid crystal light-controlling element according to any one of claims 1 to 14, wherein the liquid crystal composite is obtained using, as a precursor, a polymerizable composition containing a liquid crystal composition and a polymerizable compound, the polymerizable composition containing a photopolymerization initiator as an additive.

16. The liquid crystal light-modulating element according to any one of claims 1 to 15, wherein the light-modulating layer is the liquid crystal composite according to any one of claims 1 to 15, and the light-modulating layer is sandwiched between a pair of transparent substrates, and the transparent substrates have transparent electrodes.

17. The liquid crystal dimming element according to claim 16, wherein the transparent substrate is a glass plate or an acryl plate.

18. The liquid crystal dimming element according to claim 16, wherein the transparent substrate is a plastic film.

19. A dimming window using the liquid crystal dimming element according to any one of claims 16 to 18.

20. A smart window using the liquid crystal dimming element according to any one of claims 16 to 18.

21. Use of a liquid crystal dimming element according to any one of claims 1 to 18 in a dimming window.

22. Use of a liquid crystal dimming element according to any one of claims 1 to 18 in a smart window.