TWI836006B - Liquid crystal composite, liquid crystal light control device, light control window and smart window - Google Patents

Abstract

The present invention provides a liquid crystal composite that contains a liquid crystal composition and is suitable for light adjustment. The liquid crystal composition satisfies the following requirements: high upper limit temperature, low lower limit temperature, low viscosity, large optical anisotropy, large positive dielectric anisotropy, and high specificity. At least one of the characteristics of high resistance, high stability to light, high stability to heat, large elastic constant, small spiral pitch, or an appropriate balance between at least two of these characteristics, and the present invention The invention provides a liquid crystal dimming element having the liquid crystal composite. A liquid crystal composite, which contains a liquid crystal composition and a polymer. The liquid crystal composition contains a specific compound with large positive dielectric anisotropy and an optically active compound. The liquid crystal composite may further contain a high upper limit temperature or a low temperature. Specific compounds or dichroic pigments with lower temperature limits.

Description

Liquid crystal composite, liquid crystal dimming element, dimming window and smart window

The present invention mainly relates to a liquid crystal dimming element. More specifically, the present invention relates to a liquid crystal dimming element having a liquid crystal composite composed of a polymer and a liquid crystal component having negative dielectric anisotropy.

There are methods that utilize light scattering in liquid crystal dimming elements. Such elements are used in building materials such as window glass or room partitions, automotive parts, etc. In these elements, not only hard substrates such as glass substrates are used, but also soft substrates such as plastic films are used. For the liquid crystal composition sandwiched by these substrates, the arrangement of the liquid crystal molecules is changed by adjusting the applied voltage. By this method, the light passing through the liquid crystal composition can be controlled, so liquid crystal dimming elements are widely used in displays, optical shutters, dimming windows (Patent Document 1), smart windows (Patent Document 2), etc.

An example of a liquid crystal light modulating element is a light scattering mode polymer dispersion type element. The liquid crystal composition is dispersed in the polymer. This component has the following characteristics. The components are easy to manufacture. It is easy to control the film thickness over a large area, so large-screen components can be produced. No polarizing plate is required, so a vivid display is achieved. The field of view is wide due to the use of light scattering. Since this element has such excellent properties, it is expected to be used in dimmable glass, projection displays, large-area displays, and the like.

Another example is a polymer network type liquid crystal dimming element. In this type of element, a liquid crystal component exists in a three-dimensional network of a polymer. This component is continuous, which is different from the polymer dispersion type. This type of element also has the same characteristics as the polymer dispersion type element. There are also liquid crystal dimming elements that are a mixture of polymer network type and polymer dispersion type.

A liquid crystal composition with appropriate characteristics is used in a liquid crystal dimming element. By improving the characteristics of the composition, an element with good characteristics can be obtained. The correlation between the characteristics of the two is summarized in the following Table 1. The characteristics of the composition are further explained based on the element. The temperature range of the nematic phase is related to the temperature range in which the element can be used. The preferred upper limit temperature of the nematic phase is above about 70°C, and the preferred lower limit temperature of the nematic phase is below about -20°C. The viscosity of the composition is related to the response time of the element. In order to control the transmittance of light, a short response time is preferred. The ideal response time is 1 millisecond shorter than that of other elements. Therefore, it is preferred that the viscosity of the composition is small. It is particularly preferred that the viscosity is small at low temperatures. The elastic constant of the composition is related to the response time of the element. In order to achieve a short response time in a device, it is preferred that the elastic constant of the composition be large.

[Table 1] Characteristics of liquid crystal compositions and liquid crystal dimming elements No. Characteristics of liquid crystal compositions Characteristics of LCD dimming components 1 Nematic phase has a wide temperature range Wide usable temperature range 2 Low viscosity Short response time 3 Large optical anisotropy High haze rate 4 Positive or negative dielectric anisotropy is large Low threshold voltage and low power consumption 5 Greater than resistance Great voltage retention 6 Stable to light and heat Long life 7 Large elastic constant Short response time

The optical anisotropy of the composition is related to the haze rate of the liquid crystal dimming element. Haze rate is the ratio of diffused light to total transmitted light. When blocking light, a high haze ratio is preferred. For a large haze ratio, it is preferable that the optical anisotropy is large. The large dielectric anisotropy of the composition contributes to low threshold voltage or low power consumption in the device. Therefore, it is preferable that the dielectric anisotropy is large. A high specific resistance of the composition contributes to a high voltage retention rate in the component. Therefore, a composition having a large specific resistance in the initial stage is preferred. A composition that still has a large specific resistance after long-term use is preferred. The stability of the composition to light or heat or weather resistance is related to the life of the component. When the stability or weather resistance is good, the life span is long. Display defects such as afterimages or drip marks are also related to the life of the components. There is a demand for a device that has high weather resistance and is less likely to cause display defects.

There are normal mode and reverse mode in liquid crystal dimming components. In normal mode, the element is opaque when no voltage is applied, and becomes transparent when voltage is applied. This model is suitable for room partitions. In reverse mode, the device is transparent when no voltage is applied and becomes opaque when voltage is applied. In this mode, it becomes transparent when a component fails, so it is suitable for car windows.

We have tried to improve the liquid crystal dimming element while referring to Patent Documents 3 to 6. [Prior art documents] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 06-273725 [Patent Document 2] International Publication No. 2011-96386 [Patent Document 3] Japanese Patent Application Publication No. Sho 63-278035 [Patent Document 4] Japanese Patent Application Publication No. 01-198725 [Patent Document 5] Japanese Patent Application Publication No. 07-104262 [Patent Document 6] Japanese Patent Application Publication No. 07-175045

[Problem to be solved by the invention] An object of the present invention is to provide a liquid crystal composite suitable for light modulation by combining an optically active compound in a liquid crystal composition. Another subject is to provide a liquid crystal composite suitable for light control including a liquid crystal composition that satisfies the requirements of a high upper limit temperature of the nematic phase, a low lower limit temperature of the nematic phase, low viscosity, and large optical anisotropy. , at least one of the characteristics of large positive dielectric anisotropy, large specific resistance, high stability to light, high stability to heat, large elastic constant, and small spiral pitch. Another subject is to provide a liquid crystal composite including a liquid crystal composition that has an appropriate balance between at least two of these properties and is suitable for light modulation. Another subject is to provide a liquid crystal dimming element having such a liquid crystal composite. Another subject is to provide a liquid crystal dimming element with characteristics such as short response time, large voltage holding rate, low threshold voltage, large haze rate, high weather resistance, and long life. [Means to solve the problem]

The present invention relates to a liquid crystal composite and a liquid crystal dimming element having the liquid crystal composite. The liquid crystal composite includes a liquid crystal composition and a polymer. The liquid crystal composition contains as component A selected from the group consisting of formula (1). At least one compound among the compounds represented and an optically active compound as additive A. In formula (1), R ¹ is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; Ring A is a 1,4-cyclohexyl group, 1, 4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidine- 2,5-diyl, 1,3-dioxane-2,5-diyl or tetrahydropyran-2,5-diyl; Z ¹ is a single bond, ethylidene, vinylidene, or acetylene base, methyleneoxy ^, carbonyloxy or ^{difluoromethyleneoxy} ; X ¹ and alkyl to 12, an alkoxy group with 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine, or an alkenyloxy group with 2 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine; a is 1, 2 , 3 or 4. [Effects of the invention]

An advantage of the present invention is to provide a liquid crystal composite suitable for light modulation by combining an optically active compound in a liquid crystal composition. Another advantage is to provide a liquid crystal composite that contains a liquid crystal composition and is suitable for dimming. The liquid crystal composition satisfies the requirements of high upper limit temperature of the nematic phase, low lower limit temperature of the nematic phase, low viscosity, and large optical anisotropy. , at least one of the characteristics of large positive dielectric anisotropy, large specific resistance, high stability to light, high stability to heat, large elastic constant, and small spiral pitch. Another advantage is to provide a liquid crystal composite that includes a liquid crystal composition that has an appropriate balance between at least two of these properties and is suitable for dimming. Another advantage is to provide a liquid crystal dimming element having such a liquid crystal composite. Another advantage is to provide a liquid crystal dimming element with characteristics such as short response time, large voltage holding rate, low threshold voltage, large haze rate, high weather resistance, and long life.

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

A "liquid crystal composition" is prepared by mixing a plurality of liquid crystal compounds. Additives such as optically active compounds, antioxidants, ultraviolet absorbers, matting agents, pigments, defoaming agents, and polar compounds may be added to the liquid crystal composition as necessary. Even when an additive is added, the ratio of the liquid crystal compound is expressed as a mass percentage (mass %) based on the liquid crystal composition not containing the additive. The proportion of the additive is expressed as a mass percentage based on the liquid crystal composition not containing the additive. That is, the ratio of the liquid crystal compound or the additive is calculated based on the total amount of the liquid crystal compound. Furthermore, "mass %" is sometimes abbreviated to "%".

"Polymerizable composition" is prepared by mixing a polymerizable compound in a liquid crystal composition. That is, the polymerizable composition is a mixture of at least one polymerizable compound and a liquid crystal composition. Additives such as polymerization initiators and polymerization inhibitors are added to the polymerizable compound as needed. The ratio of the polymerization initiator and the polymerization inhibitor is expressed by the mass percentage based on the total amount of the polymerizable compound. In the case of adding additives, the ratio of the polymerizable compound or the liquid crystal composition contained in the polymerizable composition is also expressed by the mass percentage based on the polymerizable composition without the additive. "Liquid crystal composite" is generated by the polymerization treatment of the polymerizable composition. "Liquid crystal dimming element" is an element having a liquid crystal composite, and is a general term for liquid crystal panels and liquid crystal modules used for dimming.

Sometimes, the "upper limit temperature of the nematic phase" is referred to as the "upper limit temperature". Sometimes, the "lower limit temperature of the nematic phase" is referred to as the "lower limit temperature". The expression "increasing dielectric anisotropy" means that its value increases positively in the case of a composition with positive dielectric anisotropy, and that its value increases negatively in the case of a composition with negative dielectric anisotropy. "High voltage retention rate" means that the element has a high voltage retention rate not only at room temperature but also at a temperature close to the upper limit temperature in the initial stage, and that after long-term use, the element has a high voltage retention rate not only at room temperature but also at a temperature close to the upper limit temperature. Sometimes, the characteristics of a composition or element are studied through time change tests.

The compound (1z) will be used as an example to illustrate. In the formula (1z), the symbols α and β surrounded by hexagons correspond to the ring α and the ring β respectively, and represent rings such as six-membered rings and condensed rings. When the subscript 'x' is 2, there are two rings α. The two groups represented by the two rings α may be the same or different. This rule applies to any two rings α when the subscript 'x' is greater than 2. This rule also applies to other notations such as the bonding base Z. A diagonal line cutting across one side of ring β indicates that any hydrogen on ring β may be substituted by a substituent (-Sp-P). The subscript 'y' indicates the number of substituted substituents. When the subscript 'y' is 0, there is no such substitution. When the subscript 'y' is 2 or more, there are multiple substituents (-Sp-P) on ring β. The "may be the same or may be different" rule also applies in this case. Furthermore, this rule also applies when the notation Ra is used for multiple 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 consisting of alkyl, alkoxy and alkenyl. That is, the group represented by Ra and the group represented by Rb may be the same or different.

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

"Main ingredient" refers to the ingredient that accounts for the largest proportion in a mixture or composition. For example, in a mixture of 40% compound (1z), 35% compound (2z) and 25% compound (3z), the main component is compound (1z). When the component is only compound (1z), compound (1z) is also called the main component. When compound (1z) is a single compound, the compound is also called a main component.

The expression "at least one 'A'" means that the number of 'A' is arbitrary. The expression "at least one 'A' may be substituted by 'B'" means that when the number of 'A' is one, the position of 'A' is arbitrary, and when the number of 'A' is two or more, their positions can also be selected without limitation. The expression "at least one -CH ₂ - may be substituted by -O-" is sometimes used. In this case, -CH ₂ -CH ₂ -CH ₂ - can be converted to -O-CH ₂ -O- by replacing a non-adjacent -CH ₂ - with -O-. However, an adjacent -CH ₂ - is not substituted by -O-. The reason is that -OO-CH ₂ - (peroxide) is generated in the substitution.

The alkyl group of the liquid crystal compound is linear or branched, and does not include cyclic alkyl groups. Linear alkyl groups are preferred over branched alkyl groups. The same applies to terminal groups such as alkoxy and alkenyl groups. In order to increase the upper temperature limit, the stereo configuration associated with 1,4-cyclohexylene is preferred to the trans configuration over the cis configuration. Since 2-fluoro-1,4-phenylene is left-right asymmetric, there are left-facing (L) and right-facing (R). The same applies to divalent groups such as tetrahydropyran-2,5-diyl and the like. The same applies to bonding groups such as carbonyloxy (-COO- or -OCO-).

The present invention includes the following items, etc.

Item 1. A liquid crystal composite comprising a liquid crystal composition and a polymer, wherein the liquid crystal composition contains, as component A, at least one compound selected from the compounds represented by formula (1) and, as additive A, an optically active compound. In formula (1), ^R1 is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; Ring A is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; ^Z1 is a single bond, ethylene, ethenylene, ethynylene, methyleneoxy, carbonyloxy, or difluoromethyleneoxy; ^X1 and ^X2 are hydrogen or fluorine; Y ¹ is fluorine, chlorine, cyano, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine, or an alkenyloxy group having 2 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine; a is 1, 2, 3 or 4.

Item 2. The liquid crystal composite according to Item 1, wherein the liquid crystal composition contains, as component A, at least one compound selected from the group consisting of compounds represented by Formula (1-1) to Formula (1-47).

In Formula (1-1) to Formula (1-47), R ¹ is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms, and X ¹ and X ² is hydrogen or fluorine; Y ¹ is fluorine, chlorine, cyano, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine Oxy group, or an alkenyloxy group having 2 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine.

Item 3. A liquid crystal composite as described in Item 1 or Item 2, wherein the proportion of component A is in the range of 5% to 90% based on the liquid crystal composition.

Item 4. The liquid crystal composite according to any one of Items 1 to 3, wherein the liquid crystal composition contains, as component B, at least one compound selected from the compounds represented by formula (2). In formula (2), ^R2 and ^R3 are alkyl groups having 1 to 12 carbon atoms, alkoxy groups having 1 to 12 carbon atoms, alkenyl groups having 2 to 12 carbon atoms, or alkenyl groups having 2 to 12 carbon atoms in which at least one hydrogen atom is substituted with fluorine or chlorine; Ring B and Ring C are 1,4-cyclohexylene, 1,3-phenylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene or pyrimidine-2,5-diyl; ^Z2 is a single bond, ethylene, ethenylene, ethynylene, methyleneoxy or carbonyloxy; and b is 1, 2 or 3.

Item 5. The liquid crystal composite according to any one of Items 1 to 4, wherein the liquid crystal composition contains, as component B, at least one compound selected from the group consisting of compounds represented by Formula (2-1) to Formula (2-23).

In Formula (2-1) to Formula (2-23), R ² and R ³ are 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, or Alkenyl group having 2 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine.

Item 6. A liquid crystal composite as described in Item 4 or Item 5, wherein the proportion of component B is in the range of 5% to 90% based on the liquid crystal composition.

Item 7. The liquid crystal composite according to any one of Items 1 to 6, wherein the liquid crystal composition contains at least one compound selected from the compounds represented by Formula (3) as component C. In formula (3), R ⁴ and R ⁵ are hydrogen, 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, or an alkenyl group having 2 to 12 carbon atoms. base; ring D and ring F are 1,4-cyclohexylene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,4-phenylene, at least one hydrogen Fluorine- or chlorine-substituted 1,4-phenylene, naphthalene-2,6-diyl, at least one hydrogen substituted with fluorine or chlorine-substituted naphthalene-2,6-diyl, chroman-2,6-diyl , or chroman-2,6-diyl in which at least one hydrogen is substituted by fluorine or chlorine; ring E 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-difluorochrome Orthoalkyl-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-tetrafluoroindane-2,5-diyl; Z ³ and Z ⁴ are single bonds, ethyl or ethylene group, methyleneoxy group or carbonyloxy group; c is 0, 1, 2 or 3, d is 0 or 1, and the sum of c and d is less than 3.

Item 8. The liquid crystal composite according to any one of Items 1 to 7, wherein the liquid crystal composition contains as component C a compound selected from the group consisting of compounds represented by Formula (3-1) to Formula (3-35) at least one compound.

In Formula (3-1) to Formula (3-35), R ⁴ and R ⁵ are hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms. Or an alkenyloxy group having 2 to 12 carbon atoms.

Item 9. The liquid crystal composite according to Item 7 or 8, wherein the proportion of component C is in the range of 3% to 25% based on the liquid crystal composition.

Item 10. The liquid crystal composite according to any one of Items 1 to 9, wherein the polymer is derived from a precursor whose main component is the compound represented by Formula (4). In formula (4), P ¹ and P ² are polymerizable groups; Z ⁵ is an alkylene group having 1 to 20 carbon atoms. In the alkylene group, at least one hydrogen can pass through an alkyl group having 1 to 5 carbon atoms or fluorine. , chlorine or P ³ substituted, at least one -CH ₂ - can be substituted by -O-, -CO-, -COO-, -OCO-, -NH- or -N(R ⁶ )-, at least one -CH ₂ CH ₂ - may be substituted by -CH=CH- or -C≡C-, and at least one -CH ₂ - may be substituted by a carbocyclic saturated aliphatic compound, a heterocyclic saturated aliphatic compound, a carbocyclic saturated aliphatic compound, or a carbocyclic saturated aliphatic compound. Substitution with divalent radicals generated by removing two hydrogens from unsaturated aliphatic compounds, heterocyclic unsaturated aliphatic compounds, carbocyclic aromatic compounds or heterocyclic aromatic compounds. Among these divalent radicals , with a carbon number of 5 to 35, and at least one hydrogen may be substituted by R ⁶ or P ^3. Here, R ⁶ is an alkyl group with a carbon number of 1 to 12. In the alkyl group, at least one -CH ₂ - may be substituted by - O-, -CO-, -COO- or -OCO- substituted, P ³ is a polymerizable group.

Item 11. The liquid crystal composite according to Item 10, wherein P ¹ , P ² , and P ³ are groups selected from the polymerizable groups represented by Formula (P-1) to Formula (P-6). In formula (P-1) to formula (P-6), M ¹ , M ² and M ³ are hydrogen, 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 atom is substituted with fluorine or chlorine.

Item 12. The liquid crystal composite according to Item 10, wherein at least one of P ¹ , P ² , and P ³ is an acryloxy group or a methacryloxy group.

Item 13. The liquid crystal composite according to any one of Items 1 to 9, wherein the polymer is derived from a precursor whose main component is a compound represented by formula (5). In formula (5), ^M4 and ^M5 are hydrogen or methyl; ^Z6 is an alkylene group having 21 to 80 carbon atoms, in which at least one hydrogen may be substituted by an alkylene group having 1 to 20 carbon atoms, fluorine or chlorine, at least one _-CH2- may be substituted by -O-, -CO-, -COO-, -OCO-, -NH- or -N( ^R6 )-, and at least one _-CH2CH2- may be substituted by -CH=CH- or -C≡C-. Here, ^R6 is an _alkylene group having 1 to 12 carbon atoms, in which at least one _-CH2- may be substituted by -O-, -CO-, -COO- or -OCO-.

Item 14. The liquid crystal composite according to any one of Items 1 to 9, wherein the polymer is derived from a precursor whose main component is the compound represented by Formula (6). In formula (6), M ⁶ is hydrogen or methyl; Z ⁷ is a single bond or an alkylene group with 1 to 5 carbon atoms. In the alkylene group, at least one hydrogen may be substituted by fluorine or chlorine, and at least one -CH ₂ - can be substituted by -O-, -CO-, -COO- or -OCO-; R ⁷ is an alkyl group with 1 to 40 carbon atoms. In the alkyl group, at least one hydrogen can be substituted with fluorine or chlorine, and at least one -CH ₂ - may be substituted by -O-, -CO-, -COO- or -OCO-, and at least one -CH ₂ - may be substituted by a carbocyclic saturated aliphatic compound or a heterocyclic saturated aliphatic compound. A divalent radical substitution generated by removing two hydrogens from a compound, a carbocyclic unsaturated aliphatic compound, a heterocyclic unsaturated aliphatic compound, a carbocyclic aromatic compound or a heterocyclic aromatic compound, In these divalent radicals, the number of carbon atoms is 5 to 35, and at least one hydrogen can be substituted by an alkyl group having 1 to 12 carbon atoms. In the alkyl group, at least one -CH ₂ - can be substituted by -O-, -CO- , -COO- or -OCO- substitution.

Item 15. A liquid crystal composite as described in Item 14, wherein in formula (6), ^M6 is hydrogen or methyl; ^Z7 is a single bond or an alkylene group having 1 to 5 carbon atoms, in which at least one hydrogen can be replaced by fluorine or chlorine, and at least one _-CH2- can be replaced by -O-, -CO-, -COO- or -OCO-; ^R7 is an alkyl group having 1 to 40 carbon atoms, in which at least one hydrogen can be replaced by fluorine or chlorine, and at least one _-CH2- can be replaced by -O-, -CO-, -COO- or -OCO-.

Item 16. The liquid crystal composite according to any one of Items 1 to 9, wherein the polymer is derived from a precursor whose main component is represented by Formula (7), Formula (8) or Formula (9) represented compound. In formula (7), formula (8) and formula (9), ring G, ring I, ring J, ring K, ring L and ring M are 1,4-cyclohexylene group, 1,4-phenylene group, 1,4-cyclohexenyl, pyridine-2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene-2,6-diyl or fluorene-2,7-diyl group, where at least one hydrogen can pass through fluorine, chlorine, cyano, hydroxyl, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl with 1 to 5 carbon atoms, Substituted by an alkoxy group with 1 to 5 carbon atoms, an alkoxycarbonyl group with 2 to 5 carbon atoms, or an alkyl group with 1 to 5 carbon atoms; Z ⁸ , Z ¹⁰ , Z ¹² , Z ¹³ and Z ¹⁷ are single bonds, -O -, -COO-, -OCO- or -OCOO-; Z ⁹ , Z ¹¹ , Z ¹⁴ and Z ¹⁶ are single bonds, -OCH ₂ -, -CH ₂ O-, -COO-, -OCO-, -COS -, -SCO-, -OCOO-, -CONH-, -NHCO-, -CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CF ₂ CF ₂ -, -CH=CHCOO-, - OCOCH=CH-, -CH ₂ CH ₂ COO-, -OCOCH ₂ CH ₂ -, -CH=CH-, -N=CH-, -CH=N-, -N=C(CH ₃ )-, -C (CH ₃ )=N-, -N=N- or -C≡C-; Z ¹⁵ is a single bond, -O- or -COO-; Y ² is hydrogen, fluorine, chlorine, trifluoromethyl, trifluoro Methoxy, cyano, alkyl with 1 to 20 carbons, alkenyl with 2 to 20 carbons, alkoxy with 1 to 20 carbons or alkoxycarbonyl with 2 to 20 carbons; f and h are Integers from 1 to 4; k and m are integers from 0 to 3, and the sum of k and m is 1 to 4; e, g, i, j, l and n are integers from 0 to 20; M ⁷ to M ¹² are hydrogen or methyl.

Item 17. The liquid crystal composite according to any one of Items 1 to 16, wherein the additive A is at least one selected from the optically active compounds represented by Formula (10-1) to Formula (10-7) compound. In formulas (10-1) to formula (10-7), R ⁸ to R ¹⁶ are hydrogen, fluorine, chlorine, cyano, -SF ₅ or an alkyl group having 1 to 10 carbon atoms. Among the alkyl groups, at least one -CH ₂ - can be substituted by -O-, -COO- or -OCO-, at least one -CH ₂ CH ₂ - can be substituted by -CH=CH- or -C≡C-, among these groups, at least one is hydrogen Can be substituted by fluorine or chlorine; Ring N, Ring P, Ring Q, Ring T, Ring U, Ring X, Ring Y and Ring Z are 1,4-cyclohexylene, 1,4-phenylene, 1,3 -Dioxane-2,5-diyl, tetrahydropyran-2,5-diyl, tetrahydropyran-3,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5 -Diyl or bicyclo[2.2.2]octane-1,4-diyl, in these rings, at least one hydrogen can be substituted by fluorine or chlorine; Ring R, Ring S, Ring V and Ring W are 5,6 ,7,8-tetralin-1,2-diyl or naphthalene-1,2-diyl; Z ¹⁸ to Z ²⁵ are single bonds or an alkylene group with 1 to 20 carbon atoms, in the alkylene group, At least one -CH ₂ - may be substituted by -O-, -CO-, -COO- or -OCO-, and at least one -CH ₂ CH ₂ - may be substituted by -CH=CH- or -C≡C-, which In the group, at least one hydrogen may be substituted by fluorine or chlorine; X ³ to X ⁸ are hydrogen or fluorine; p, q, r, s, t, u, v and w are 1, 2 or 3.

Item 18. The liquid crystal composite as described in any one of Items 1 to 17, wherein the proportion of the additive A is in the range of 0.03% to 25% based on the liquid crystal composition.

Item 19. The liquid crystal composite according to any one of Items 1 to 18, wherein a helical pitch of the liquid crystal composition is less than 10 μm.

Item 20. The liquid crystal composite according to any one of Items 1 to 19, wherein the liquid crystal composition contains a dichroic dye as Additive B.

Item 21. The liquid crystal composite according to Item 20, wherein the additive B is selected from the group consisting of benzothiadiazoles, diketopyrrolopyrroles, azo compounds and anthraquinones at least one dichroic pigment in the anthraquinones.

Item 22. The liquid crystal composite according to Item 20 or Item 21, wherein the proportion of Additive B is in the range of 0.01% to 25% based on the liquid crystal composition.

Item 23. The liquid crystal composite according to any one of Items 1 to 22, wherein based on the liquid crystal composite, the proportion of the polymer is in the range of 3% to 40%, and the proportion of the liquid crystal composition is in the range of 97% to 60% range.

Item 24. The liquid crystal composite according to any one of Items 1 to 22, wherein based on the liquid crystal composite, the proportion of the polymer is in the range of 10% to 70%, and the proportion of the liquid crystal composition is in the range of 90% to 30% range.

Item 25. A liquid crystal dimming element, wherein the dimming layer is a liquid crystal composite as described in any one of items 1 to 24, and the dimming layer is sandwiched by a pair of transparent substrates, and the transparent substrates have transparent electrodes.

Item 26. The liquid crystal dimming element according to item 25, wherein the transparent substrate is a glass plate or an acrylic plate.

Item 27. A liquid crystal dimming element as described in Item 25, wherein the transparent substrate is a plastic film.

Item 28. The liquid crystal dimming element according to any one of Items 25 to 27, which has the liquid crystal composite according to any one of Items 1 to 24, and has an illumination intensity (180 W/m ² ), The haze change rate before and after the weather resistance test conducted under the conditions of irradiation time (100 hours) and tank temperature (35°C) is 20% or less.

Item 29. A dimming window using the liquid crystal dimming element according to any one of Items 25 to 28.

Item 30. A smart window using a liquid crystal dimming element as described in any one of Items 25 to 28.

Item 31. A use of a liquid crystal composite, wherein the liquid crystal composite is the liquid crystal composite as described in any one of Items 1 to 24, and is used in a liquid crystal dimming element.

Item 32. Use of a liquid crystal composite, which is the liquid crystal composite according to any one of Items 1 to 24, which is used in a liquid crystal dimming element whose transparent substrate is a plastic film.

Item 33. Use of a liquid crystal composite, the liquid crystal composite being the liquid crystal composite according to any one of Items 1 to 24, which is used in a dimming window.

Item 34. Use of a liquid crystal composite, the liquid crystal composite being the liquid crystal composite according to any one of Items 1 to 24, which is used in smart windows.

The present invention also includes the following items. (a) The liquid crystal composite as described above, wherein the liquid crystal composition contains, as component A, at least one compound in which Y ¹ is fluorine in the compound (1) described in item 1. (b) The liquid crystal composite as described above, wherein the liquid crystal composition contains, as component A, at least one compound in which Y ¹ is a cyano group in the compound (1) described in item 1.

The present invention also includes the following items. (c) The liquid crystal composite as described above, wherein the liquid crystal composition contains as component A selected from the group consisting of compound (1-1), compound (1-2), compound (1-3), and compound described in item 2 (1-9), compound (1-13), compound (1-16), compound (1-21), compound (1-22), compound (1-23), compound (1-24), compound ( At least one compound among compound (1-27), compound (1-28), compound (1-33), compound (1-36), compound (1-41) and compound (1-42).

The present invention also includes the following items. (d) The liquid crystal composite as described above, wherein the liquid crystal composition contains, as component B, at least one compound selected from the group consisting of compound (2-1), compound (2-2), compound (2-3), compound (2-4), compound (2-6), compound (2-9), compound (2-10), compound (2-12), compound (2-13), compound (2-14), compound (2-16), compound (2-17), compound (2-19) and compound (2-21) described in item 5.

The present invention also includes the following items. (e) The liquid crystal composite as described above, wherein the liquid crystal composition contains as component C selected from the group consisting of compound (3-1), compound (3-5), compound (3-6), and compound described in item 8 At least one compound among (3-7), compound (3-8), compound (3-12), compound (3-14), compound (3-19) and compound (3-34).

The present invention also includes the following items. (f) The liquid crystal composite as described above, wherein the proportion of the polymer is in the range of 3% to 40% and the proportion of the liquid crystal component is in the range of 97% to 60% based on the liquid crystal composite. (g) The liquid crystal composite as described above, wherein the proportion of the polymer is in the range of 4% to 20% and the proportion of the liquid crystal component is in the range of 96% to 80% based on the liquid crystal composite. (h) The liquid crystal composite as described above, wherein the proportion of the polymer is in the range of 5% to 10% and the proportion of the liquid crystal component is in the range of 95% to 90% based on the liquid crystal composite.

The present invention also includes the following items. (i) The liquid crystal composite as described above, wherein based on the liquid crystal composite, the proportion of the polymer is in the range of 10% to 70%, and the proportion of the liquid crystal composition is in the range of 90% to 30%. (j) The liquid crystal composite as described above, wherein based on the liquid crystal composite, the proportion of the polymer is in the range of 20% to 60%, and the proportion of the liquid crystal composition is in the range of 80% to 40%. (k) The liquid crystal composite as described above, wherein based on the liquid crystal composite, the proportion of the polymer is in the range of 30% to 40%, and the proportion of the liquid crystal composition is in the range of 70% to 60%.

The present invention also includes the following items: (1) The liquid crystal composite as described above, wherein the precursor of the liquid crystal composite is a polymerizable composition, and the polymerizable composition contains a liquid crystal composition, a polymerizable compound, and a photopolymerization initiator as an additive C.

We have attempted to improve liquid crystal dimming elements. In order to improve liquid crystal dimming elements, we considered an approach of using a chiral nematic composition instead of the nematic composition listed in Table 1. The reason is that we expect that a liquid crystal composite composed of a polymer combined in a chiral nematic composition that is a mixture of a nematic composition and an optically active compound can be used in a liquid crystal dimming element. We have studied the possibility and completed the present invention.

The present invention relates to a liquid crystal composite comprising a polymer and a liquid crystal composition having a chiral nematic phase, and a liquid crystal dimming element having the composite. In order to be suitable for a dimming element, an optically active compound (chiral agent) is added to the nematic liquid crystal composition. The chiral nematic liquid crystal composition is prepared in the following manner. The liquid crystal composite comprises a chiral nematic liquid crystal composition and a polymer. The types of compounds suitable as components constituting the liquid crystal composite are not reported in the literature. We have found that a certain liquid crystal composite exhibits a focal conic state, a planar state, a homeotropic state, etc. depending on the conditions, and is suitable for a dimming element.

The present invention is described in the following order. First, the liquid crystal composite is described. Second, the liquid crystal composition is described. Third, the main characteristics of the liquid crystal compound and the main effects of the compound on the liquid crystal composition or element are described. Fourth, the combination or preferred ratio of the liquid crystal compounds is described. Fifth, the preferred form of the liquid crystal compound is described. Sixth, the preferred liquid crystal compound is shown. Seventh, the preferred form of the polymerizable compound and an example thereof are described. Eighth, the preferred form of the optically active compound and an example thereof are described. Ninth, the synthesis method of the component compounds is described. Tenth, the additives that can be added to the polymerizable composition are described. Finally, the liquid crystal dimming element is described.

First, the liquid crystal composite will be explained. The precursor of the liquid crystal composite is a polymeric composition. Liquid crystal composites are produced by polymerization of polymerizable compositions. The polymerizable composition is a mixture of a polymerizable compound and a liquid crystal composition. An optically active compound as additive A is added to the liquid crystal composition. The polymerizable composition is put into the element and polymerized. The polymer produced by polymerization undergoes phase separation to provide a liquid crystal composite. Elements having a liquid crystal composite are classified into polymer stable alignment type, polymer network type, and polymer dispersion type based on the polymerization of the polymer.

When the proportion of polymer is small, elements with polymer sustained alignment are generated. Call it PSA component for short. Example 1 of International Publication No. 2012-050178 describes "adding a monomer so that it becomes 0.5 wt% with respect to a liquid crystal material" (paragraph 0105). As can be seen from this description, in the PSA element, a small amount of the polymerizable compound is added to the liquid crystal material (liquid crystal composition). 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 device is shortened.

When the polymer ratio is large, a polymer dispersion type element is generated. In this type of element, the liquid crystal composition is dispersed in the polymer like droplets. Each droplet is microencapsulated and not continuous. The liquid crystal molecules are arranged along the inner wall of the capsule, so they are in a random state. Since the refractive index of the polymer is different from that of the liquid crystal molecules, the incident light is scattered. The element is opaque. When a voltage is applied to the element, the refractive index of the liquid crystal molecules changes. If the refractive index is the same as that of the polymer, the incident light passes through the element and the element becomes transparent.

On the other hand, when the proportion of the polymer is moderate, a polymer network type element is generated. In this type of element, the polymer has a three-dimensional grid structure, and the liquid crystal composition is surrounded by the grid and is continuous. The liquid crystal molecules are in a random state and the components are opaque. When a voltage is applied to the element, the liquid crystal molecules are aligned in the direction of the electric field, so the element becomes transparent. In order to efficiently cause light scattering, the ratio of the liquid crystal composition based on the liquid crystal composite is preferably large. When the droplet or grid is large, the driving voltage is low. Therefore, from the viewpoint of low driving voltage, the proportion of the polymer is preferably small. When the droplet or grid is small, the response time is short. Therefore, from the viewpoint of a short response time, a large proportion of the polymer is appropriate.

In order to scatter incident light, the preferred ratio of the polymer is in the range of about 3% to about 40% based on the liquid crystal composite. The more preferred ratio is in the range of about 4% to about 20% based on the liquid crystal composite. The particularly preferred ratio is in the range of about 5% to about 10% based on the liquid crystal composite. Since the sum of the polymer and the liquid crystal composition is 100%, the ratio of the liquid crystal composition can be easily calculated. Furthermore, 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.

In order to improve the adhesion between the dimming layer (liquid crystal composite) and the substrate, the preferred ratio of the polymer is in the range of about 10% to about 70% based on the liquid crystal composite. The more preferred ratio is in the range of about 20% to about 60% based on the liquid crystal composite. The particularly preferred ratio is in the range of about 30% to about 40% based on the liquid crystal composite.

When the polymer ratio is in the range of about 3% to about 70%, a polymer network type device or a polymer dispersion type device is generated. The polymer network type and the polymer dispersion type are mixed according to the polymer ratio. In these devices, unlike PSA devices, a polarizing plate is not required. In the polymer network type device, an alignment film is used as needed.

The method for preparing a liquid crystal composite from a polymerizable composition is as follows. First, a polymerizable composition is sandwiched between a pair of substrates. The clamping is performed by a vacuum injection method or a liquid crystal dripping method at a temperature higher than the upper limit temperature of the polymerizable composition. In devices produced by these methods, display defects such as flow marks and drip marks may occur. Flow marks are traces of polymeric composition flowing through components. Drop marks are traces left after dropping the polymerizable composition. It is preferable to suppress such display defects. Then, the polymerizable compound is polymerized by heat or light. It is preferred to irradiate ultraviolet rays during polymerization. Through polymerization, the polymer undergoes phase separation from the polymerizable composition. Thereby, a light modulation layer (liquid crystal composite) is formed between the substrates.

Second, the liquid crystal composition is explained. The composition contains a variety of liquid crystal compounds. The composition may also contain additives. Additives include optically active compounds, antioxidants, ultraviolet absorbers, matting agents, pigments, defoaming agents, polymerization initiators, polymerization inhibitors, polar compounds, etc. From the viewpoint of a liquid crystal compound, this composition is classified into composition A and composition B. Composition A may contain not only a liquid crystal compound selected from the group consisting of compound (1), compound (2) and compound (3), but also other liquid crystal compounds, additives, and the like. "Other liquid crystal compounds" are liquid crystal compounds different from compound (1), compound (2), and compound (3). Such compounds are mixed into the composition for the purpose of further adjusting the properties.

The composition B substantially contains only a liquid crystal compound selected from the group consisting of compound (1), compound (2) and compound (3). "Substantially" means that although the composition B may contain additives, it does not contain other liquid crystal compounds. The number of components of the composition B is smaller than that of the composition A. From the perspective of cost reduction, the composition B is superior to the composition A. From the perspective of further adjusting the properties by mixing other liquid crystal compounds, the composition A is superior to the composition B.

Third, the main characteristics of the liquid crystal compound and the main effects of the compound on the liquid crystal composition or element are explained. The main properties of the component compounds are summarized in Table 2. In Table 2, L refers to large or high, M refers to medium, and S refers to small or low. The symbols L, M, and S are classifications based on qualitative comparisons between component compounds, and the symbol 0 (zero) means less than S.

[Table 2] Characteristics of liquid crystal compounds Compound Compound (1) Compound (2) Compound (3) Upper limit temperature S～L S～L S～L Viscosity M～L S～M M～L Optical anisotropy M～L S～L M～L Dielectric anisotropy S～L 0 M～L ¹⁾ Specific resistance L L L 1) The value of dielectric anisotropy is negative, and the sign indicates the magnitude of the absolute value

The main effects of component compounds on the properties of the composition are as follows. Compound (1) increases dielectric anisotropy. Compound (2) increases the upper limit temperature or lowers the lower limit temperature. Compound (3) increases the dielectric constant in the short axis direction of liquid crystal molecules.

Fourth, the combination or preferred ratio of liquid crystal compounds is described. Preferred combinations are component A + component B, component A + component C, or component A + component B + component C. Particularly preferred combinations are component A + component B or component A + component B + component C. It is also possible to combine a specific one or two compounds selected from component A with component B (or component C). The same is true for component B or component C.

In order to improve the dielectric anisotropy, the preferred proportion of component A is about 5% or more, and in order to reduce the lower limit temperature, the preferred proportion of component A is about 90% or less. A particularly preferred ratio is in the range of about 10% to about 85%. A particularly optimal ratio is in the range of about 20% to about 80%.

In order to increase the upper temperature limit or reduce the lower temperature limit, the preferred ratio of component B is about 5% or more, and in order to increase the dielectric anisotropy, the preferred ratio of component B is about 90% or less. A particularly preferred ratio is in the range of about 10% to about 85%. A particularly preferred ratio is in the range of about 20% to about 80%.

In order to increase the dielectric constant in the short axis direction of the liquid crystal molecules, the preferred proportion of component C is about 3% or more. In order to reduce the lower limit temperature, the preferred proportion of component C is about 25% or less. A particularly preferred ratio is in the range of about 5% to about 20%. A particularly optimal ratio is in the range of about 5% to about 15%.

Fifth, the preferred form of the liquid crystal compound is described. In formula (1), formula (2) and formula (3), ^R1 is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms. In order to improve the stability to light or heat, ^R1 is preferably an alkyl group having 1 to 12 carbon atoms.

^R2 and ^R3 are alkyl groups having 1 to 12 carbon atoms, alkoxy groups having 1 to 12 carbon atoms, alkenyl groups having 2 to 12 carbon atoms, or alkenyl groups having 2 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine. In order to increase the upper temperature limit or lower the lower temperature limit, preferably ^R2 or ^R3 is an alkenyl group having 2 to 12 carbon atoms, and in order to increase the stability to light or heat, preferably ^R2 or ^R3 is an alkyl group having 1 to 12 carbon atoms.

R ⁴ and R ⁵ are hydrogen, 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, or an alkenyloxy group having 2 to 12 carbon atoms. In order to improve the stability to light or heat, the preferred R ⁴ or R ⁵ is an alkyl group with 1 to 12 carbon atoms. In order to improve the dielectric constant in the short axis direction of the liquid crystal molecules, the preferred R ⁴ or R ⁵ It is an alkoxy group having 1 to 12 carbon atoms.

Preferred alkyl groups are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl or octyl. In order to reduce the viscosity, particularly preferred alkyl groups are methyl, ethyl, propyl, butyl or pentyl.

Preferred alkoxy groups are methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy or heptyloxy. In order to reduce the viscosity, particularly preferred alkoxy groups 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. For reducing viscosity, particularly preferred alkenyl groups are vinyl, 1-propenyl, 3-butenyl or 3-pentenyl. The preferred stereoconfiguration of -CH=CH- in these alkenyl groups depends on the position of the double bond. In order to reduce viscosity and other reasons, among alkenyl groups such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, 3-pentenyl, and 3-hexenyl, the preferred trans configuration. Among alkenyl groups such as 2-butenyl, 2-pentenyl, and 2-hexenyl, the cis configuration is preferred.

Preferred alkenyloxy groups are vinyloxy, allyloxy, 3-butenyloxy, 3-pentenyloxy or 4-pentenyloxy. In order to reduce the viscosity, particularly preferred alkenyloxy groups are allyloxy or 3-butenyloxy.

Preferred examples of the alkyl group in which at least one hydrogen is substituted with fluorine or chlorine are fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, 5-fluoropentyl, 6-fluorohexyl, 7-fluoroheptyl or 8-fluorooctyl. In order to improve the dielectric anisotropy, particularly preferred examples are 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl or 5-fluoropentyl.

Preferable examples of alkenyl groups in which at least one hydrogen is substituted by fluorine or chlorine are 2,2-difluorovinyl, 3,3-difluoro-2-propenyl, and 4,4-difluoro-3-butenyl. , 5,5-difluoro-4-pentenyl or 6,6-difluoro-5-hexenyl. For reducing viscosity, particularly preferred examples are 2,2-difluorovinyl or 4,4-difluoro-3-butenyl.

Ring A is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl or tetrahydropyran-2,5-diyl. In order to improve the optical anisotropy, the preferred ring A is 1,4-phenylene or 2-fluoro-1,4-phenylene. In order to increase the upper limit temperature, the stereo configuration associated with 1,4-cyclohexylene is the trans configuration is better than the cis configuration. Tetrahydropyran-2,5-diyl is or , preferably .

Ring B and ring C are 1,4-cyclohexylene, 1,3-phenylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, and 2,5-difluoro-1 ,4-phenyl or pyrimidine-2,5-diyl. In order to increase the upper limit temperature or to lower the lower limit temperature, the preferred ring B or ring C is 1,4-cyclohexylene group, and in order to lower the lower limit temperature, the preferred ring B or ring C is 1,4-phenylene group.

Ring D and ring F are 1,4-cyclohexylene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,4-phenylene, at least one hydrogen is modified by fluorine or Chlorine-substituted 1,4-phenylene, naphthalene-2,6-diyl, at least one hydrogen substituted with fluorine or chlorine, naphthalene-2,6-diyl, chroman-2,6-diyl or at least Chroman-2,6-diyl with one hydrogen substituted by fluorine or chlorine. In order to lower the lower limit temperature or to raise the upper limit temperature, the preferred ring D or ring F is 1,4-cyclohexylene group. In order to lower the lower limit temperature, the preferred ring D or ring F is 1,4-phenylene group.

Ring E 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 (DBFF2), 4,6-difluorodibenzothiophene-3,7-diyl (DBTF2) or 1,1,6,7-tetrafluoroindan-2,5-diyl (InF4). In order to reduce the viscosity, the preferred ring E is 2,3-difluoro-1,4-phenylene, and in order to increase the dielectric constant of the liquid crystal molecule in the short axis direction, the preferred ring E is 4,6-difluorodibenzothiophene-3,7-diyl.

Z ¹ is a single bond, an ethyl group, a vinyl group, an ethynyl group, a methyleneoxy group, a carbonyloxy group or a difluoromethyleneoxy group. In order to increase the upper limit temperature, Z ¹ is preferably a single bond, and in order to increase the dielectric anisotropy, Z ¹ is preferably a difluoromethyleneoxy group. Particularly preferred Z ¹ is a single bond. Z ² is a single bond, an ethyl group, a vinyl group, an ethynyl group, a methyleneoxy group or a carbonyloxy group. In order to increase the stability to light or heat, preferred Z ² is a single bond. Z ³ and Z ⁴ are single bonds, an ethyl group, a vinyl group, a methyleneoxy group or a carbonyloxy group. In order to reduce viscosity, Z ³ or Z ⁴ is preferably a single bond, in order to reduce the minimum temperature, Z ³ or Z ⁴ is preferably an ethylene group, and in order to increase the dielectric constant in the short axis direction of the liquid crystal molecule, Z ³ or Z ⁴ is preferably a methyleneoxy group. Z ³ or Z ⁴ is particularly preferably a single bond.

Divalent radicals such as methyleneoxy are bilaterally asymmetric. In methyleneoxy, -CH ₂ O- is preferred to -OCH ₂ -. In carbonyloxy, -COO- is preferred to -OCO-. In difluoromethyleneoxy, -CF ₂ O- is preferred to -OCF ₂ -.

a is 1, 2, 3 or 4. In order to lower the lower limit temperature, a is preferably 2, and in order to increase the dielectric anisotropy, a is preferably 3. b is 1, 2 or 3. In order to lower the lower limit temperature, b is preferably 1, and in order to increase the upper limit temperature, b is preferably 2 or 3. c is 0, 1, 2 or 3, d is 0 or 1, and the sum of c and d is 3 or less. To lower the lower limit temperature, c is preferably 1, and to raise the upper limit temperature, c is 2 or 3. In order to reduce the viscosity, the preferred d is 0, and in order to reduce the lower limit temperature, the preferred d is 1.

X ¹ and X ² are hydrogen or fluorine. In order to increase the upper limit temperature, X ¹ or X ² is preferably hydrogen, and in order to increase the dielectric anisotropy, X ¹ or X ² is preferably fluorine.

Y ¹ is fluorine, chlorine, cyano, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen is substituted with fluorine or chlorine, or at least one Alkenyloxy group having 2 to 12 carbon atoms in which hydrogen is substituted by fluorine or chlorine. In order to reduce the viscosity, the preferred Y ¹ is fluorine, and in order to improve the dielectric anisotropy, the preferred Y ¹ is a cyano group.

A preferred example of the alkyl group in which at least one hydrogen is substituted by fluorine or chlorine is trifluoromethyl. A preferred example of the alkoxy group in which at least one hydrogen is substituted by fluorine or chlorine is trifluoromethoxy. A preferred example of the alkenyloxy group in which at least one hydrogen is substituted by fluorine or chlorine is trifluoroethyleneoxy.

Sixth, preferred liquid crystal compounds are shown. Preferred compound (1) is compound (1-1) to compound (1-47) described in item 2. Among these compounds, at least one of the components A is preferably compound (1-1), compound (1-2), compound (1-7), compound (1-9), compound (1-13), compound (1-16), compound (1-17), compound (1-23), compound (1-24), compound (1-28), compound (1-29), compound (1-30), compound (1-33), compound (1-34), compound (1-41) or compound (1-42). Preferably, at least two of the components A are a combination of compound (1-1) and compound (1-2), compound (1-1) and compound (1-9), compound (1-2) and compound (1-9), compound (1-1) and compound (1-16), compound (1-2) and compound (1-16), compound (1-9) and compound (1-16), compound (1-9) and compound (1-24), compound (1-16) and compound (1-24), compound (1-9) and compound (1-41), compound (1-16) and compound (1-41), compound (1-9) and compound (1-42), or compound (1-16) and compound (1-42).

Preferred compound (2) is compound (2-1) to compound (2-23) described in item 5. Among these compounds, it is preferred that at least one of component B is compound (2-1), compound (2-2), compound (2-3), compound (2-6), compound (2-9), compound (2-10), compound (2-11), compound (2-12), compound (2-13), compound (2-16), compound (2-20) or compound (2-21). It is preferred that at least two of component B are a combination of compound (2-2) and compound (2-9), compound (2-2) and compound (2-10), compound (2-2) and compound (2-12), compound (2-9) and compound (2-10), compound (2-9) and compound (2-12) or compound (2-10) and compound (2-12).

Preferred compounds (3) are compounds (3-1) to (3-35) described in item 8. Among these compounds, it is preferred that at least one component C is compound (3-1), compound (3-3), compound (3-6), compound (3-8), compound (3-10), compound (3-14) or compound (3-34). Preferably, at least two types of component C are compound (3-1) and compound (3-8), compound (3-1) and compound (3-14), compound (3-3) and compound (3-8) ), compound (3-3) and compound (3-14), compound (3-3) and compound (3-34), compound (3-6) and compound (3-8), compound (3-6) and compound (3-10) or a combination of compound (3-6) and compound (3-14).

Seventh, a preferred form of the polymerizable compound and an example thereof will be described. The polymerizable compound derives a polymer by polymerization. The precursor of the polymer is a polymerizable compound. The polymerizable compound may be a single compound or a mixture of multiple compounds. Preferred polymerizable compounds are compound (4), compound (5) or compound (6). Preferred polymerizable compounds are compound (7), compound (8) or compound (9). The polymerizable compound may be a mixture of compounds selected from compound (4) to compound (9). The mixture may contain a polymerizable compound different from the compounds (4) to (9). Such a mixture contains compound (4), compound (5) or compound (6) as a main component. Such a mixture contains compound (7), compound (8) or compound (9) as a main component.

7-1. Compound (4) In formula (4), Z ⁵ is an alkylene group having 1 to 20 carbon atoms. In the alkylene group, at least one hydrogen can pass through an alkyl group having 1 to 5 carbon atoms, fluorine, or chlorine. Or P ³ substituted, at least one -CH ₂ - can be substituted by -O-, -CO-, -COO-, -OCO-, -NH- or -N(R ⁶ )-, at least one -CH ₂ CH ₂ - Can be substituted by -CH=CH- or -C≡C-, at least one -CH ₂ - can be substituted by a carbocyclic saturated aliphatic compound, a heterocyclic saturated aliphatic compound, a carbocyclic unsaturated A divalent radical substitution generated by removing two hydrogens from an aliphatic compound, a heterocyclic unsaturated aliphatic compound, a carbocyclic aromatic compound, or a heterocyclic aromatic compound. Among these divalent radicals, carbon The number is 5 to 35, and at least one hydrogen may be substituted by R ⁶ or P ³ . Here, R ⁶ is an alkyl group having 1 to 12 carbon atoms, and in the alkyl group, at least one -CH ₂ - may be substituted by -O-, -CO-, -COO- or -OCO-.

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

Preferred Z ⁵ is an alkylene group with 1 to 20 carbon atoms. In the alkylene group, at least one hydrogen may be substituted by an alkyl group with 1 to 5 carbon atoms, and at least one -CH ₂ - may be substituted with -O-. At least one -CH ₂ - may be substituted by a divalent radical generated by removing two hydrogens from a carbocyclic saturated aliphatic compound or a carbocyclic aromatic compound, wherein the number of carbon atoms in these divalent radicals is 5 to 35. Particularly preferred Z ⁵ is an alkylene group having 1 to 20 carbon atoms. In the alkylene group, at least one hydrogen may be substituted by an alkyl group having 1 to 5 carbon atoms, and at least one -CH ₂ - may be substituted with -O-.

In order to improve the compatibility with the liquid crystal composition, preferred Z ⁵ contains a ring structure such as 1,4-cyclohexylene group or 1,4-phenylene group. In order to easily form a lattice structure, preferred Z ⁵ contains a chain structure such as an alkylene group.

^P1 , ^P2 and ^P3 are polymerizable groups. Preferred polymerizable groups are those of formula (P-1) to (P-6). In these formulas, the wavy lines indicate the positions of the bonds. Particularly preferred polymerizable groups are those of formula (P-1) to (P-3). ^P1 , ^P2 and ^P3 may be acryloxy or methacryloxy.

In formula (P-1) to formula (P-6), ^M1 , ^M2 and ^M3 are hydrogen, 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 atom is substituted by fluorine or chlorine. In order to improve the reactivity, preferably ^M1 , ^M2 or ^M3 is hydrogen or methyl. More preferably ^M1 is hydrogen or methyl, and more preferably ^M2 or ^M3 is hydrogen.

An example of the compound (4) is as follows. In Formula (4-1), p is an integer from 1 to 6, in Formula (4-2), q is an integer from 5 to 20, and in Formula (4-4), r is an integer from 1 to 15.

In the compound (4), when there are many polymerizable groups, the polymer surrounding the droplets becomes strong due to cross-linking, or the network of the polymer becomes dense. Preferred polymerizable compounds have at least one acryloyloxy group (-OCO-CH=CH ₂ ) or methacryloyloxy group (-OCO-(CH ₃ )C=CH ₂ ). Compound (4) provides the corresponding polymer by polymerization. When compound (4) is volatile, its oligomer can be used. The preferred polymer is colorless, transparent, and insoluble in the liquid crystal composition. A preferable polymer has excellent adhesion to the device substrate and reduces the driving voltage. In order to enhance this effect, a polymerizable compound different from compound (4) may be used together.

7-2. Compound (5) In formula (5), M ⁴ and M ⁵ are hydrogen or methyl. In order to improve the reactivity, the preferred M ⁴ or M ⁵ is hydrogen.

Z ⁶ is an alkylene group having 21 to 80 carbon atoms, in which at least one hydrogen atom may be substituted by an alkylene group having 1 to 20 carbon atoms, fluorine or chlorine, at least one -CH ₂ - atom may be substituted by -O-, -CO-, -COO-, -OCO-, -NH- or -N(R ⁶ )-, and at least one -CH ₂ CH ₂ - atom may be substituted by -CH=CH- or -C≡C-. Here, R ⁶ is an alkylene group having 1 to 12 carbon atoms, in which at least one -CH ₂ - atom may be substituted by -O-, -CO-, -COO- or -OCO-. In order to achieve low voltage driving, preferably Z ⁶ is an alkylene group having 21 to 60 carbon atoms, in which at least one hydrogen atom may be substituted by an alkylene group having 1 to 20 carbon atoms, and at least one -CH ₂ - atom may be substituted by -O-, -COO- or -OCO-.

In order to achieve low voltage driving, it is particularly preferred that Z ⁶ is an alkylene group in which at least one hydrogen is substituted by an alkyl group. When both hydrogens of the alkylene group are substituted by alkyl groups, it is preferred to avoid steric hindrance. For example, the two alkyl groups are sufficiently separated, or an alkyl group having 1 to 5 carbon atoms is used in one of the alkyl groups. The same is true when at least three hydrogens are substituted by alkyl groups.

An example of compound (5) is as follows. In formula (5-1), ^R8 and ^R10 are alkyl groups having 1 to 5 carbon atoms, ^R9 and ^R11 are alkyl groups having 5 to 20 carbon atoms, in which at least one _-CH2- may be substituted by -O-, -CO-, -COO- or -OCO-, and ^Z8 is an alkylene group having 10 to 30 carbon atoms, in which at least one _-CH2- may be substituted by -O-, -CO-, -COO- or -OCO-.

An example of the compound (5-1) is as follows. In the formula (5-1-1) and _the formula (5-1-2), for example _, ^R8 and ^R10 are ethyl groups, _and ^R9 _and ^R11 are _{-CH2OCOC9H19 , -CH2OCOC10H21 , -CH2OC8H17 or -CH2OC11H23 .}

Compound (5) is diacrylate or dimethacrylate. Z ⁶ in formula (5) is an alkylene group, etc., so the polymer easily forms a network structure. When the molecular chain of Z ⁶ is short, the cross-linked sites of the polymer are close, so the mesh becomes smaller. When the molecular chain of Z ⁶ is long, the cross-linked sites of the polymer are far away, and the degree of freedom of molecular movement is increased, so the driving voltage is reduced. When Z ⁶ is branched, the degree of freedom is further increased, so the driving voltage is further reduced. In order to enhance this effect, a polymerizable compound different from compound (5) may be used together.

7-3. Compound (6) In formula (6), M ⁶ is hydrogen or methyl. In order to improve the reactivity, the preferred M ⁶ is hydrogen.

^Z7 is a single bond or an alkylene group having 1 to 5 carbon atoms, in which at least one hydrogen atom may be replaced by fluorine or chlorine, and at least one _-CH2- atom may be replaced by -O-, -CO-, -COO- or -OCO-. Preferably, ^Z7 is a single bond or an alkylene group having 1 to 5 carbon atoms, in which at least one _-CH2- atom may be replaced by -O-, -CO-, -COO- or -OCO-.

^R7 is an alkyl group having 1 to 40 carbon atoms, in which at least one hydrogen atom may be replaced by fluorine or chlorine, at least one _-CH2- atom may be replaced by -O-, -CO-, -COO- or -OCO-, at least one _-CH2- atom may be replaced by a divalent group formed by removing two hydrogen atoms 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 carbon atoms is 5 to 35, at least one hydrogen atom may be replaced by an alkyl group having 1 to 12 carbon atoms, in which at least one _-CH2- atom may be replaced by -O-, -CO-, -COO- or -OCO-. Preferably, ^R7 is an alkyl group having 5 to 30 carbon atoms. More preferably, ^R7 is a branched alkyl group having 5 to 30 carbon atoms.

An example of compound (6) is as follows. In formula (6-1) to formula (6-5), R ¹² is an alkyl group having 5 to 20 carbon atoms, in which at least one -CH ₂ - may be substituted by -O-, -CO-, -COO- or -OCO-; R ¹³ and R ¹⁴ are alkyl groups having 3 to 10 carbon atoms, in which at least one -CH ₂ - may be substituted by -O-, -CO-, -COO- or -OCO-.

Compound (6) is acrylate or methacrylate. When R ⁷ in formula (6) has a cyclic structure, the affinity with the liquid crystal composition is improved. When R ⁷ is an alkylene group, the polymer easily forms a network structure. In this polymer, the degree of freedom of molecular motion increases due to the alkylene group, so the driving voltage decreases. In order to further enhance this effect, a polymerizable compound different from compound (6) may be used together.

7-4. Compounds (7) to (9) In formula (7), formula (8) and formula (9), ring G, ring I, ring J, ring K, ring L and ring M are 1,4-cyclohexylene, 1,4-phenylene, 1,4-cyclohexenyl, pyridine-2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene-2,6-diyl or fluorene-2,7-diyl, and at least one hydrogen here may be substituted by fluorine, chlorine, cyano, hydroxyl, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbon atoms, alkoxy having 1 to 5 carbon atoms, alkoxycarbonyl having 2 to 5 carbon atoms or alkyl having 1 to 5 carbon atoms. In formula (7), formula (8) and formula (9), the preferred ring is 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. The particularly preferred ring is 1,4-cyclohexylene or 1,4-phenylene.

Z ⁸ , Z ¹⁰ , Z ¹² , Z ¹³ and Z ¹⁷ are a single bond, -O-, -COO-, -OCO- or -OCOO-. Z ⁹ , Z ¹¹ , Z ¹⁴ and Z ¹⁶ are a single bond, -OCH ₂ -, -CH ₂ O-, -COO-, -OCO-, -COS-, -SCO-, -OCOO-, -CONH-, -NHCO-, -CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CF ₂ CF ₂ -, -CH=CHCOO-, _-OCOCH =CH-, -CH 2 CH ₂ COO-, -OCOCH ₂ CH ₂ -, -CH=CH-, -N=CH-, -CH=N-, -N=C(CH ₃ )-, -C(CH ₃ )=N-, -N=N- or -C≡C-. Z ¹⁵ is a single bond, -O- or -COO-. Preferred Z ⁸ , Z ¹⁰ , Z ¹² , Z ¹³ or Z ¹⁷ is a single bond or -O-. Preferred Z ⁹ , Z ¹¹ , Z ¹⁴ or Z ¹⁶ is a single bond, -OCH ₂ -, -CH ₂ O-, -COO-, -OCO-, -CH ₂ CH ₂ -, -CH ₂ CH ₂ COO- or -OCOCH ₂ CH ₂ -.

^Y2 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 2 to 20 carbon atoms. Preferred ^Y2 is cyano, alkyl or alkoxy.

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

^M7 to ^M12 are hydrogen or methyl.

An example of compound (7) is as follows.

In Formula (7-1) to Formula (7-24), M ⁷ is hydrogen or methyl, and e is an integer from 1 to 20.

An example of the compound (8) is as follows.

In Formula (8-1) to Formula (8-31), M ⁸ and M ⁹ are hydrogen or methyl, and g and i are integers from 1 to 20.

An example of compound (9) is as follows.

In Formula (9-1) to Formula (9-10), M ¹⁰ , M ¹¹ and M ¹² are hydrogen or methyl, and j, l and n are integers from 1 to 20.

Compound (7), compound (8) and compound (9) have at least one acryloyloxy group (-OCO-CH=CH ₂ ) or methacryloyloxy group (-OCO-(CH ₃ )C=CH ₂ ) . Liquid crystalline compounds have mesogens (a rigid portion that induces liquid crystallinity), and these compounds also have mesogens. Therefore, these compounds are aligned in the same direction together with the liquid crystal compound by the action of the alignment film. This alignment is also maintained after polymerization. This kind of liquid crystal composite has high transparency. In order to improve other characteristics, a polymerizable compound different from compound (7), compound (8), and compound (9) may be used together.

Eighth, a preferred form of the optically active compound and an example thereof will be described. In TN mode liquid crystal display elements, optically active compounds can also be used. In this mode, two substrates have alignment films. The rubbing direction is rotated 90 degrees and the substrate is arranged. The optically active compound is added to twist the arrangement of liquid crystal molecules by 90 degrees between the substrates. The spiral pitch is quite larger than 10 μm. On the other hand, the spiral pitch of the liquid crystal dimming element is 10 μm or less. The helical pitch becomes smaller by increasing the amount of optically active compound. Therefore, the optically active compound preferably has a large compatibility with the composition.

Preferred optically active compounds are compounds (10-1) to compounds (10-7). The structures of these compounds are similar to those of compounds having liquid crystallinity. From the viewpoint of high compatibility or small helical pitch, these compounds are preferred. Compound (10-4) and compound (10-5) have an asymmetric axis. Compound (10-6) has an asymmetric carbon.

In formula (10-1) to formula (10-7), R ⁸ to R ¹⁶ are hydrogen, fluorine, chlorine, cyano, -SF ₅ , or an alkyl group having 1 to 10 carbon atoms, in which at least one -CH ₂ - may be substituted by -O-, -COO-, -OCO-, -CH=CH-, or -C≡C-, and in which at least one hydrogen may be substituted by fluorine or chlorine. Preferred R ⁸ to R ¹⁶ are hydrogen, an alkyl group having 1 to 10 carbon atoms, or an alkyl group having 1 to 10 carbon atoms in which at least one -CH ₂ - is substituted by -CH=CH- or -C≡C-. Particularly preferred R ⁸ to R ¹⁶ are alkyl groups having 1 to 10 carbon atoms.

Ring N, ring P, ring Q, ring T, ring U, ring X, ring Y and ring Z are 1,4-cyclohexylene, 1,4-phenylene, 1,3-dioxane-2,5-diyl, tetrahydropyran-2,5-diyl, tetrahydropyran-3,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl or bicyclo[2.2.2]octane-1,4-diyl, and at least one hydrogen in these rings may be substituted by fluorine or chlorine. Preferred ring N, ring P, ring Q, ring T, ring U, ring X, ring Y or ring Z is 1,4-cyclohexylene or 1,4-phenylene. Ring R, Ring S, Ring V and Ring W are 5,6,7,8-tetrahydronaphthalene-1,2-diyl or naphthalene-1,2-diyl. Preferred Ring R, Ring S, Ring V or Ring W is 5,6,7,8-tetrahydronaphthalene-1,2-diyl.

Z ¹⁸ to Z ²⁵ are single bonds or alkylene groups with 1 to 20 carbon atoms. In the alkylene group, at least one -CH ₂ - can be passed through -O-, -CO-, -COO-, -OCO-, - CH=CH- or -C≡C-substituted, at least one hydrogen in these groups may be substituted by fluorine or chlorine. Preferred Z ¹⁸ to Z ²⁵ are single bonds, alkylene groups with 1 to 20 carbon atoms, or at least one -CH ₂ -alkylene group with 1 to 20 carbon atoms substituted by -O-, -COO- or -OCO-. alkyl. Particularly preferred Z ¹⁸ to Z ²⁵ are single bonds, -OCH ₂ -, -COO- or -OCO-.

^X3 to ^X8 are hydrogen or fluorine. In order to increase the helical twisting power (HTP), preferably ^X3 to ^X8 are fluorine.

p, q, r, s, t, u, v and w are 1, 2 or 3. Preferably p, q, r, s, t, u, v or w is 2 or 3.

Based on the liquid crystal composition, the preferred ratio of the optically active compound is in the range of about 0.03% to about 25%. A particularly preferred ratio is in the range of about 0.03% to about 20%. A particularly preferred ratio is in the range of about 0.03% to about 15%. A preferred helical pitch in the liquid crystal composition is 10 μm or less. A particularly preferred helical pitch is 5 μm or less. A particularly preferred helical pitch is 3 μm or less.

An example of the compound (10-1) to the compound (10-7) is as follows.

Ninth, the synthesis method of the component compounds will be explained. These compounds can be synthesized using known methods. Example synthesis method. Compound (1-9) and compound (1-16) were synthesized by the method described in Japanese Patent Application Laid-Open No. 2-233626. Compound (2-1) was synthesized by the method described in Japanese Patent Application Laid-Open No. Sho 59-176221. Compound (3-1) was synthesized by the method described in Japanese Patent Publication No. 2-503441. Antioxidants are already commercially available. Compound (11-1) described below is available from Sigma-Aldrich Corporation. Compound (11-2) and the like are synthesized by the method described in U.S. Patent No. 3660505. The polymerizable compound is commercially available or can be synthesized by known methods.

Compounds whose synthesis methods are not documented can be synthesized by methods described in the following books: "Organic Syntheses" (John Wiley & Sons, Inc.), "Organic Reactions" Reactions" (John Wiley & Sons, Inc.), "Comprehensive Organic Synthesis" (Pergamon Press), "New Experimental Chemistry Lectures" ( Maruzen) etc. The composition is prepared from the compound obtained in the above manner using a known method. For example, the component compounds are mixed and then dissolved in each other by heating.

Tenth, additives that can be added to the polymerizable composition will be described. Such additives include antioxidants, ultraviolet absorbers, matting agents, pigments, defoaming agents, polymerization initiators, polymerization inhibitors, polar compounds, etc. The additive may be added to the liquid crystal composition or the polymerizable compound instead of the polymerizable composition.

The compound ( Antioxidants such as compounds 11-1) to (11-3) are added to the composition.

In order to prevent degradation caused by ultraviolet rays, an ultraviolet absorber may also be added to the composition. Low-volatility compounds are effective for maintaining a high voltage retention rate not only at room temperature but also at a temperature close to the upper limit temperature after the element has been used for a long time. In order to obtain the above effect, the preferred ratio of the antioxidant is about 50 ppm or more, and in order not to reduce the upper limit temperature or to increase the lower limit temperature, the preferred ratio of the antioxidant is about 600 ppm or less. The most preferred ratio is in the range of about 100 ppm to about 300 ppm.

Preferred examples of ultraviolet absorbers are benzophenone derivatives, benzoate derivatives, triazole derivatives, and the like. Also preferred are photostabilizers such as amines having stereohindrance. Preferred examples of photostabilizers are compounds (12-1) to (12-16), and the like. In order to obtain the above-mentioned effect, the preferred ratio of these absorbers or stabilizers is about 50 ppm or more, and in order not to lower the upper limit temperature or to not increase the lower limit temperature, the preferred ratio of these absorbers or stabilizers is about 10,000 ppm or less. A particularly preferred ratio is in the range of about 100 ppm to about 10,000 ppm.

The matting agent is a compound that prevents the decomposition of the liquid crystal compound by receiving light energy absorbed by the liquid crystal compound and converting it into thermal energy. Preferable examples of the matting agent include compounds (13-1) to compounds (13-7) and the like. In order to obtain the above effect, the preferred ratio of the matting agents is about 50 ppm or more. In order not to increase the lower limit temperature, the preferred ratio of the matting agents is about 20,000 ppm or less. Particularly preferred ratios are in the range of about 100 ppm to about 10,000 ppm.

In order to be suitable for guest host (GH) mode components, dichroic dye (dichroic dye) is added to the composition. LCD dimming elements are sometimes used as room dividers. In this case, a pigment is added to the polymerizable composition for the purpose of absorbing specific light. A variety of pigments can be added. Liquid crystal dimming elements are sometimes used to block sunlight. In this case, a black (or blackened) dichroic pigment is added to the liquid crystal composition. Black is produced by mixing cyan, magenta, and yellow dichroic pigments. A black dichroic dye is described in Example 42 of Japanese Patent Application Laid-Open No. 2006-193742. The pigment is prepared by mixing three azo compounds and anthraquinones.

Examples of dichroic pigments are benzothiadiazoles, diketopyrrolopyrroles, azo compounds, azomethine compounds, methine compounds, anthraquinones, merocyanines, naphthoquinones, tetrazines, pyrromethenes, and rylenes such as perylenes or terrylenes.

This dichroic dye has at least some of the following characteristics. a) The dye molecule is linear. b) A skeleton unique to dichroic dyes such as a benzothiadiazole ring or a diketopyrrolopyrrole ring exists in the center of the molecule. c) The benzene ring or thiophene ring constituting the molecule together with the unique skeleton is located on the same plane. d) The side chain is an alkyl group or an alkoxy group. e) There is a conjugated double bond in the center.

Preferred dichroic pigments are benzothiadiazoles, diketopyrrolopyrroles, azo compounds, anthraquinones, and rylene. Particularly preferred dichroic pigments are benzothiadiazoles, diketopyrrolopyrroles, azo compounds, and rylene. The skeletons of these four pigments are shown below. For example, benzothiadiazoles refer to dichroic pigments having a benzothiadiazole ring.

Examples of commercially available dichroic pigments are G-207, G-241, G-305, G-470, G-471, G-472, LSB-278, LSB-335, NKX-1366, NKX-3538, NKX-3540, NKX-3622, NKX-3739, NKX-3742, NKX-3773, NKX-4010, and NKX-4033 manufactured by Nagase Sangyo; and S-428, SI-426, SI-486, M-412, and M-483 manufactured by Mitsui Fine Chemicals.

Based on the liquid crystal composition, the preferred proportion of dichroic pigment is in the range of about 0.01% to about 25%. A particularly preferred ratio is in the range of about 0.02% to about 20%. A particularly preferred ratio is in the range of about 0.03% to about 15%.

In order to prevent foaming, defoaming agents such as dimethyl silicone oil and methyl phenyl silicone oil are added to the composition. In order to obtain the above-mentioned effect, the preferred ratio of the defoaming agent is about 1 ppm or more, and in order to prevent display defects, the preferred ratio of the defoaming agent is about 1000 ppm or less. Particularly preferred ratios are in the range of about 1 ppm to about 500 ppm.

When the polymerizable compound is polymerized, it is preferable to irradiate it with ultraviolet rays. Examples of ultraviolet irradiation lamps include metal halide lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, and the like. When a photopolymerization initiator is used, the wavelength of ultraviolet rays is preferably within the absorption wavelength region of the photopolymerization initiator. Avoid the absorption wavelength range of liquid crystal compositions. The preferred wavelength is above 330 nm. A particularly preferred wavelength is above 350 nm, for example 365 nm. The reaction can be carried out near room temperature or under heating.

Polymerization can also be carried out in the presence of a polymerization initiator such as a photopolymerization initiator. Suitable conditions for carrying out polymerization or suitable types and amounts of initiators are known to those skilled in the art and are documented in the literature. For example, as photopolymerization initiators, Irgacure 651 (registered trademark; BASF), Irgacure 184 (registered trademark; BASF) or Darocur 1173 ( Registered trademark; BASF) is suitable for free radical polymerization.

When storing the polymerizable compound, a polymerization inhibitor may be added to prevent polymerization. The polymerizable compound is usually mixed in the liquid crystal composition without removing the polymerization inhibitor. Examples of the polymerization inhibitor are hydroquinone, hydroquinone derivatives such as methyl hydroquinone, 4-tert-butyl o-cyclopentylphenol, 4-methoxyphenol, phenothiazine, etc.

Polar compounds are organic compounds that have polarity. Here, compounds having ionic bonds are not included. Atoms such as oxygen, sulfur, and nitrogen are electrically negative and tend to have a partial negative charge. Carbon and hydrogen are neutral or tend to have a partial positive charge. Polarity results from the uneven distribution of partial charges among different kinds of atoms in a compound. For example, the polar compound has at least one partial structure such as -OH, -COOH, -SH, -NH ₂ , >NH, >N-.

The polar group has non-covalent bonding interaction with the surface of the glass substrate, metal oxide film, etc. Polar compounds are adsorbed on the surface of the substrate through the action of polar groups and control the alignment of liquid crystal molecules. Polar compounds not only control liquid crystal molecules, but also sometimes control polymeric compounds. This effect is expected for polar compounds.

Finally, the liquid crystal dimming element is explained. The nematic composition is a mixture of rod-shaped liquid crystal compounds. The chiral nematic composition is prepared by adding an optically active compound (chiral agent) to the nematic composition. The liquid crystal molecules are given a right twist or a left twist by the action of the optically active compound, thereby changing to a focal cone state. In a tiny area, the liquid crystal molecules are arranged in layers, and the directions of the liquid crystal molecules in each layer are twisted in a spiral. The axis of twist in the spiral structure is called the spiral axis. The length corresponding to one period in the spiral structure is called the spiral pitch. The focal cone state is an aggregate of such tiny areas, and the direction of the spiral axis is random.

Figure 1 shows the dimming element in normal mode. The light modulating layer (liquid crystal composite) is sandwiched between two substrates. In the component on the left (not applied), the triangles (liquid crystal molecules) represent tiny regions of the focal conic state, and the curves represent the mesh of the polymer. In the element (applied) on the right, the vertical rod (liquid crystal molecule) shows a homeotropic state.

A polymerizable composition is prepared by mixing a polymerizable compound into a composition in a focal cone state. This composition is put into a display element. This component has an indium tin oxide (ITO) electrode. This component is not aligned. The element is irradiated with ultraviolet rays while applying a voltage, whereby a polymerization reaction proceeds, thereby producing an element having a liquid crystal composite. Because light scatters, the element is opaque. By applying a voltage to the element, the liquid crystal molecules transition from the focal conic state to the vertical state. Since light passes through, the element is transparent. The vertical state returns to the focal conic state as a result of removing the voltage.

Figure 2 shows a dimming element in reverse mode. This element has a horizontal alignment film, which differs from the element of Figure 1 in this respect. Liquid crystal molecules are in a planar state due to the alignment film. The component is transparent. By applying a voltage to this element, the liquid crystal molecules transition into a focal conic state. The element becomes opaque due to the scattering of light. As the voltage is removed, the focal conic state returns to the planar state.

Changes over time may occur due to long-term use of components. The haze rate sometimes changes compared to the initial stage. The change in haze rate should be small. When the haze change rate is small, a good transparent/opaque state can be maintained. The haze change rate is preferably 20% or less. The best haze change rate is less than 10%. The best haze change rate is less than 5%.

The haze change rate is an important factor in the longevity of liquid crystal dimming elements. When testing the weather resistance of the element, the haze change rate before and after is preferably small. In order to achieve a small haze change rate, it is important to select the type of liquid crystal compound and combine it with a specific polymerizable compound to study the ratio of each component compound. In order to obtain better results, it is useful to study the type or amount of additives, polymerization conditions, etc.

If the component is used for a long time, flicker may occur in the display screen. It is speculated that the flicker is related to the ghosting of the image, and when the element is driven with AC, the flicker is caused by a difference between the potential of the positive frame and the potential of the negative frame. The flicker rate (%) can be expressed by (|brightness when a positive voltage is applied - brightness when a negative voltage is applied|)/(average brightness)×100. The flicker rate of the component is preferably in the range of 0% to 1%.

When the device is used for a long time, the brightness may decrease partially. One example of such display failure is line streaking. This is a phenomenon in which the brightness between two adjacent electrodes decreases in a striped manner due to repeated application of different voltages to the two adjacent electrodes. This phenomenon is presumed to be caused by the accumulation of ionic impurities contained in the liquid crystal composition near the electrodes.

This type of light control element has a light control layer (liquid crystal composite) sandwiched between a pair of transparent substrates having transparent electrodes. An example of the substrate is a material that is not easily deformed, such as a glass plate, quartz plate, or acrylic plate. 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 may have transparent electrodes thereon. Examples of transparent electrodes are indium tin oxide (tin-doped indium oxide (ITO)) or conductive polymers. The substrate may also have an alignment film on the transparent electrode.

For alignment films, films such as polyimide or polyvinyl alcohol are suitable. For example, the polyimide alignment film can be made by coating the polyimide resin composition on a transparent substrate and thermally curing it at a temperature above about 180°C, and using cotton or rayon cloth as needed. Obtained by friction treatment.

A pair of substrates are placed facing each other with the transparent electrode layer on the inner side. Spacers may be placed to make the thickness between the substrates uniform. Examples of spacers are glass particles, plastic particles, aluminum oxide particles, photo spacers, etc. The preferred thickness of the dimming layer is about 2 μm to about 50 μm, and more preferably about 5 μm to about 20 μm. When bonding a pair of substrates, a commonly used sealant may be used. An example of a sealant is an epoxy-based thermosetting composition.

In such an element, a light absorbing layer, a diffuse reflection plate, etc. can be disposed on the back side of the element if necessary. Functions such as specular reflection, diffuse reflection, retroreflective reflection, and total image reflection can also be added.

This type of component has the function of a dimming film or dimming glass. When the element is in film form, it can be attached to an existing window or sandwiched between a pair of glass plates to create laminated glass. Such elements are used for windows placed on exterior walls or for partitions between conference rooms and corridors. That is, there are applications such as electronic blinds, dimming windows, and smart windows. Furthermore, the function as an optical switch can be used in a liquid crystal shutter or the like. [Example]

The present invention will be further described in detail through examples. The present invention is not limited by these examples. Composition (M1), composition (M2), etc. are described in Examples. The mixture of the composition (M1) and the composition (M2) is not described in the Examples. However, the mixture is deemed to be disclosed as well. Mixtures of at least two compositions selected from the examples are also deemed to be disclosed. It is reasonable to think that the liquid crystal composite containing these mixtures or the liquid crystal dimming element having the composite belongs to the present invention and has the effects of the present invention. The synthesized compounds are identified by methods such as nuclear magnetic resonance (NMR) analysis. The properties of compounds, compositions and components are measured by the following methods.

NMR analysis: DRX-500 manufactured by Bruker BioSpin was used for the measurement. In the ¹ H-NMR measurement, the sample was dissolved in a deuterated solvent such as CDCl ₃ , and the measurement was performed at room temperature at 500 MHz and 16 cumulative times. Tetramethylsilane was used as an internal standard. In the ¹⁹ F-NMR measurement, CFCl ₃ was used as an internal standard and the measurement was performed at 24 cumulative times. In the description of nuclear magnetic resonance spectra, s means singlet, d means doublet, t means triplet, q means quartet, quin means quintet, sex means sextet, m means multiplet, and br means broad.

Gas chromatography analysis: A GC-14B gas chromatograph manufactured by Shimadzu Corporation was used for the measurement. The carrier gas was helium (2 mL/min). The sample vaporizer was set to 280°C, and the detector (flame ionization detector (FID)) was set to 300°C. When separating the component compounds, a capillary column DB-1 (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm; stationary liquid phase is dimethyl polysiloxane; non-polar) manufactured by Agilent Technologies Inc. was used. The column was kept at 200°C for 2 minutes and then heated to 280°C at a rate of 5°C/min. After the sample was prepared as an acetone solution (0.1%), 1 μL of it was injected into the sample vaporizer. The recording instrument is a C-R5A chromatograph manufactured by Shimadzu Corporation (Chromatopac) or its equivalent. The obtained gas chromatogram shows the retention time and peak area of the peak corresponding to the component compound.

The solvent used to dilute the sample can be chloroform, hexane, etc. In order to separate component compounds, the following capillary column can also be used. HP-1 manufactured by Agilent Technologies Co., Ltd. (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm), Rtx-1 manufactured by Restek Corporation (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm), BP-1 manufactured by Australia's SGE International Pty. Ltd (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm). To prevent overlapping of compound peaks, a capillary column CBP1-M50-025 manufactured by Shimadzu Corporation (length 50 m, inner diameter 0.25 mm, film thickness 0.25 μm) can be used.

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

Measurement sample: When measuring the properties of a composition or a device having the composition, the composition is used directly as a sample. When measuring the properties of a compound, a sample for measurement is prepared by mixing the compound (15%) with a mother liquid crystal (85%). The property value of the compound is calculated using the extrapolation method based on the value obtained by the measurement. (Extrapolated value) = {(measured value of the sample) - 0.85 × (measured value of the mother liquid crystal)}/0.15. When the lamellar phase (or crystal) precipitates at 25°C at this ratio, the ratio of the compound to the mother liquid crystal is changed in the order of 10%: 90%, 5%: 95%, and 1%: 99%. The extrapolation method is used to obtain the values of the upper limit temperature, optical anisotropy, viscosity, and dielectric anisotropy associated with the compound.

The following mother liquid crystals were used.

Measurement method: Use the following method to measure the characteristics. Most of these methods are methods described in the JEITA standards (JEITA·ED-2521B) reviewed and established by the Japan Electronics and Information Technology Industries Association (JEITA), or are modified. method of success. The twisted nematic (TN) element used for measurement did not have a thin film transistor (TFT) installed.

(1) Upper limit temperature of nematic phase (NI; °C): Place a sample on the hot plate of a melting point measuring device including a polarizing microscope, and heat at a rate of 1 °C/min. The temperature at which a part of the sample changes from the nematic phase to an isotropic liquid is measured. The upper limit temperature of the nematic phase is sometimes simply referred to as the "upper limit temperature".

(2) Lower limit temperature of nematic phase (T _C ; ℃): A sample with nematic phase was placed in a glass bottle and stored in a freezer at 0℃, -10℃, -20℃, -30℃ and -40℃ for 10 days, and the liquid crystal phase was observed. For example, when the sample remains in the nematic phase at -20℃ and changes to a crystalline or lamellar phase at -30℃, T _C is recorded as <-20℃. The lower limit temperature of the nematic phase is sometimes referred to as the "lower limit temperature".

(3) Viscosity (volume viscosity; eta; measured at 20°C; mPa·s): An E-type rotational viscometer manufactured by Tokyo Keiki Co., Ltd. was used for measurement.

(4) Viscosity (rotational viscosity; γ1; measured at 25°C; mPa·s): Based on "Molecular Crystals and Liquid Crystals" Issue 259 by M. Imai et al. The measurement was performed using the method described on page 37 (1995). A sample was placed in a TN device with a twist angle of 0° and a distance (cell gap) between two glass substrates of 5 μm. A voltage is applied to the component in steps of 0.5 V in the range of 16 V to 19.5 V. After no voltage was applied for 0.2 seconds, the application was repeated under the conditions of applying only one rectangular wave (rectangular pulse; 0.2 seconds) and no voltage (2 seconds). The peak current and peak time of the transient current generated by this application are measured. The rotational viscosity value is obtained based on these measured values and the calculation formula (10) described on page 40 of the paper by M. Imai et al. The value of the dielectric anisotropy required for this calculation is determined by the method described below using an element that measures the rotational viscosity.

(5) Optical anisotropy (refractive index anisotropy; Δn; measured at 25°C): Measured using light with a wavelength of 589 nm and an Abbe refractometer with a polarizing plate installed on the eyepiece. After rubbing the surface of the main drum in one direction, drop the sample onto the main drum. 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 polarization is perpendicular to the direction of rubbing. The value of optical anisotropy is calculated according to the formula Δn=n∥-n⊥.

(6) Dielectric anisotropy (Δε; measured at 25°C): A sample was placed in a TN element with a distance (cell gap) of 9 μm between two glass substrates and a twist angle of 80 degrees. A sine wave (10 V, 1 kHz) was applied to the element, and the dielectric constant (ε∥) in the long axis direction of the liquid crystal molecules was measured after 2 seconds. A sine wave (0.5 V, 1 kHz) was applied to the element, and the dielectric constant (ε⊥) in the short axis direction of the liquid crystal molecules was measured after 2 seconds. The value of dielectric anisotropy is calculated by the formula Δε=ε∥-ε⊥.

(7) Threshold voltage (Vth; measured at 25°C; V): An LCD5100 luminance meter manufactured by Otsuka Electronics Co., Ltd. was used for measurement. The light source is a halogen lamp. A sample was placed in a normally white mode TN element with a distance (cell gap) of 0.45/Δn (μm) between two glass substrates and a twist angle of 80 degrees. The voltage (32 Hz, rectangular wave) applied to this element is increased from 0 V to 10 V in steps of 0.02 V. At this time, the element is irradiated with light from the vertical direction, and the amount of light transmitted through the element is measured. A voltage-transmittance curve is created in which the transmittance is 100% when the light amount reaches the maximum and the transmittance is 0% when the light amount is the minimum. The threshold voltage is expressed as the voltage when the transmittance reaches 90%.

(8) Voltage holding rate (VHR; measured at 25°C; %): The TN element used in the measurement has a polyimide alignment film, and the distance (cell gap) between two glass substrates is 5 μm. A sample is placed in the TN element and sealed with an adhesive cured by ultraviolet rays. The TN element was placed in a constant temperature bath at 60°C and charged by applying a pulse voltage (1 V, 60 microseconds, 3 Hz). Use a high-speed voltmeter to measure the attenuated voltage during 166.6 milliseconds, and find the area A between the voltage curve per unit period and the horizontal axis. Area B is the area without attenuation. The voltage retention rate is expressed as the percentage of area A relative to area B.

(9) Voltage holding rate (UV-VHR; measured at 25°C; %): A TN element with a sample placed in it was irradiated with 5 milliwatt ultraviolet rays for 166.6 minutes using black light as a light source. The voltage holding rate is measured to evaluate the stability against ultraviolet rays. The structure of the TN element and the method of measuring the voltage holding ratio are described in Measurement (8). Compositions with a large UV-VHR have great stability against ultraviolet rays. The UV-VHR is preferably 90% or more, more preferably 95% or more.

(10) Voltage holding ratio (heating VHR; measured at 25°C; %): After heating a TN device containing a sample in a constant temperature bath at 120°C for 20 hours, the voltage holding ratio is measured to evaluate thermal stability. The structure of the TN device or the method for measuring the voltage holding ratio is described in measurement (8). A composition having a large heating VHR has great thermal stability. The heating VHR is preferably 90% or more, and more preferably 95% or more.

(11) Response time (τ; measured at 25°C; ms): The LCD5100 model luminance meter manufactured by Otsuka Electronics Co., Ltd. was used for measurement. The light source is a halogen lamp. The low-pass filter is set to 5 kHz. A sample was placed in a TN element in normally white mode with a distance (cell gap) of 5.0 μm between two glass substrates and a twist angle of 80 degrees. Apply a square wave (60 Hz, 5 V, 0.5 seconds) to the element. At this time, the element is irradiated with light from the vertical direction, and the amount of light transmitted through the element is measured. When the amount of light reaches the maximum, the transmittance is deemed to be 100%, and when the amount of light reaches the minimum, the transmittance is deemed to be 0%. Rise time (τr: rise time; milliseconds) is the time required for the transmittance to change from 90% to 10%. Fall time (τf: fall time; milliseconds) is the time required for the transmittance to change from 10% to 90%. The response time is expressed by the sum of the rise time and fall time found in the manner described.

(12) Elastic constant (K; measured at 25°C; pN): The measurement was performed using an HP4284A inductance-capacitance-resistance (LCR) meter manufactured by Yokogawa-Hewlett-Packard Co., Ltd. The sample was placed in a horizontally aligned element in which the distance between two glass substrates (cell gap) was 20 μm. A charge ranging from 0 V to 20 V was applied to the element, and the electrostatic capacitance and applied voltage were measured. The measured electrostatic capacitance (C) and applied voltage (V) values were fitted using equations (2.98) and (2.101) in the "Liquid Crystal Device Handbook" (Nikkan Kogyo Shimbun, p. 75), and the values of K11 and K33 were obtained from equation (2.99). Next, K22 is calculated using the previously determined values of K11 and K33 in formula (3.18) on page 171 of the "Liquid Crystal Device Handbook" (Nikkan Kogyo Shimbun Co., Ltd.). The elastic constant is represented by the average value of K11, K22, and K33 determined in the above manner.

(13) Specific resistance (ρ; measured at 25°C; Ωcm): Place 1.0 mL of sample into a container equipped with an electrode. A DC voltage (10 V) was applied to the container, and the DC current after 10 seconds was measured. The specific resistance is calculated from the following formula. (Specific resistance) = {(voltage) × (capacitance of the container)}/{(DC current) × (dielectric constant of vacuum)}

(14) Helical pitch (P; measured at room temperature; μm): Helical pitch is measured using the wedge method. Refer to page 196 of "LCD Handbook" (published in 2000, Maruzen). The sample was placed in a wedge-shaped cell and left to stand at room temperature for 2 hours. The distance between the disclination lines (disclination lines) was observed using a polarizing microscope (Nikon Co., Ltd., trade name: MM40/60 series). d2-d1). The spiral pitch (P) is calculated from the following equation in which the angle of the wedge-shaped unit is expressed as θ. P=2×(d2-d1)×tanθ.

(15) Dielectric constant in the short axis direction (ε⊥; measured at 25°C): Place the test into a TN element with a distance (cell gap) of 9 μm between two glass substrates and a twist angle of 80 degrees. Like. A sine wave (0.5 V, 1 kHz) was applied to the element, and the dielectric constant (ε⊥) in the short axis direction of the liquid crystal molecules was measured after 2 seconds.

(16) Pretilt angle (degrees): A spectroscopic ellipsometer M-2000U (manufactured by J. A. Woollam Co., Inc.) was used to measure the pretilt angle.

(17) Alignment stability (liquid crystal alignment axis stability): Evaluate changes in the liquid crystal alignment axis on the electrode side of fringe field switching (FFS) elements. Measure the liquid crystal alignment angle ϕ on the electrode side before applying stress (before), then apply a square wave of 4.5 V, 60 Hz to the device for 20 minutes, buffer for 1 second, and measure the electrode side again after 1 second and 5 minutes. Liquid crystal alignment angle ϕ (after). From these values, the change in the liquid crystal alignment angle (Δϕ; degrees) after 1 second and 5 minutes is calculated using the following formula. Δϕ(degree)=ϕ(after)-ϕ(before) These determinations are based on J. Hilfiker, B. Johs, C. Herzinger, J. F. Elman, E. Mumba This is done with reference to "Thin Solid Films" by E. Montbach, D. Bryant and P. J. Bos, 455-456 (2004) 596-600. It can be said that the smaller Δϕ is, the smaller the change rate of the liquid crystal alignment axis is, and the liquid crystal molecules are more stable.

(18) Flicker rate (measured at 25°C; %): When measured, a multimedia display tester (multimedia display tester) 3298F manufactured by Yokogawa Electric Co., Ltd. was used. The light source is a light emitting diode (LED). A sample was placed in a normally black mode device with a distance (cell gap) of 3.5 μm between two glass substrates and an anti-parallel rubbing direction. The component is sealed using UV-hardened adhesive. 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. While applying this voltage to the element, the sensor unit is brought close to the element and the displayed flicker rate is read.

(19) Line Image Sticking Parameter (LISP; %): Line afterimage is produced by applying electrical stress to components. Measure the brightness of the area where the line afterimage exists and the brightness of the remaining area (reference area). The ratio of brightness reduction due to line afterimage is calculated, and the size of the line afterimage is expressed by this ratio.

19a) Measurement of brightness: An image of the component was taken using an imaging colorimeter (PM-1433F-0, manufactured by Radiant Zemax). The image was analyzed using software (Prometric 9.1, manufactured by Radiant Zemax) to calculate the brightness of each region of the component. The light source used was an LED backlight with an average brightness of 3500 cd/ ^m2 .

19b) Setting of stress voltage: Place a sample into an FFS device with a matrix structure (16 cells of 4 vertical cells × 4 horizontal cells) with a cell gap of 3.5 μm, and use an adhesive cured with ultraviolet rays to seal the device. seal. Polarizing plates are respectively arranged on the upper surface and lower surface of the element in such a manner that the polarization axes are orthogonal. The element is illuminated with light and a voltage (rectangular wave, 60 Hz) is applied. The voltage was increased step by step in units of 0.1 V within the range of 0 V to 7.5 V, and the brightness of the transmitted light at each voltage was measured. The voltage when the brightness reaches maximum is referred to as V255. The voltage when the brightness reaches 21.6% of V255 (ie, 127 gray levels) is referred to as V127.

19c) Stress conditions: Apply V255 (rectangular wave, 30 Hz) to the stress area at 60°C for 23 hours, and apply 0.5 V (rectangular wave, 30 Hz) to the reference area to display a checkerboard pattern. Then, V127 (rectangular wave, 0.25 Hz) was applied, and the brightness was measured with an exposure time of 4000 milliseconds.

19d) Calculation of line residual images: The calculation uses 4 units in the central part of the 16 units (2 units in the vertical direction × 2 units in the horizontal direction). The 4 units are divided into 25 areas (5 units in the vertical direction × 5 units in the horizontal direction). The average brightness of the 4 areas located at the four corners (2 units in the vertical direction × 2 units in the horizontal direction) is referred to as brightness A. The area formed by removing the areas at the four corners from the 25 areas is a cross shape. In the 4 areas formed by removing the central intersection area from the cross-shaped area, the minimum brightness is referred to as brightness B. The line residual image is calculated by the following formula. (Line residual image) = (Brightness A-Brightness B)/Brightness A×100. The smaller the line residual image, the better.

(20) Face Image Sticking Parameter (FISP); %): A face image sticking is generated by applying electrical stress to the device. The brightness of the area where the face image sticks and the brightness of the rest of the area are measured at 25°C. The ratio of the brightness change caused by the face image sticking is calculated, and the size of the face image sticking is expressed by this ratio.

20a) "Brightness measurement", "Stress voltage setting", and "Stress conditions" shall be in the order described in the "Line residual image" section.

20b) The facial residual image is calculated by the following formula. (Facial residual image) = (Brightness C - Brightness D) / Brightness D × 100. Here, Brightness C is the average brightness of 8 units with V255 applied, and Brightness D is the average brightness of 8 units with 0.5V applied. The facial residual image should be as small as possible. When the dielectric anisotropy of the liquid crystal composition is positive, the facial residual image is represented by P-FISP. When the dielectric anisotropy of the liquid crystal composition is negative, the facial residual image is represented by N-FISP.

(21) Haze rate (%): A haze meter NDH5000 (manufactured by Nippon Denshoku Industries Co., Ltd.) was used to measure the haze rate.

(22) Fog change rate (%): Perform weather resistance test on components. Measure the fog before and after the test, and calculate the fog change rate. The test is conducted in accordance with Japanese Industrial Standards (JIS) K5600-7-7, accelerated weather resistance and accelerated light resistance (xenon lamp method). The measurement is performed using a super xenon weather meter SX75 manufactured by Suga Test Instruments Co., Ltd. The measurement conditions are illumination (UVA; 180 W/m ² ), irradiation time (100 hours), blackboard temperature (63℃±2℃), tank temperature (35℃), and tank relative humidity (40%RH). UVA refers to ultraviolet A.

(23) Characteristics of dimming components When measuring the characteristics of a liquid crystal display element, an element having a glass substrate with a transparent electrode is usually used. On the other hand, in liquid crystal dimming elements, plastic films are sometimes used as substrates. Therefore, a device in which the substrate was made of polycarbonate was produced, and characteristics such as threshold voltage and response time were measured. This measured value was compared with the case of a glass substrate element. As a result, the two measured values were approximately the same. Therefore, the characteristics were measured using glass substrate elements and the results were described.

The following are examples of compositions. Liquid crystal compounds are represented by symbols based on the definitions in Table 3 below. In Table 3, the stereo configuration associated with 1,4-cyclohexylene is trans. The numbers in parentheses after the marked compounds represent the chemical formula to which the compounds belong. The symbol (-) refers to other liquid crystal compounds. Finally, the characteristic values of the compositions are summarized.

[table 3]

The following compositions were used in the examples.

[Composition (M1)] 5-HB-CL (1-1) 12% 3-BB(F)B(F,F)-F (1-24) 6% 3-BB(F,F)XB( F,F)-F (1-28) 20% 3-BB(F)B(F,F)XB(F,F)-F (1-41) 4% 4-BB(F)B(F, F)XB(F,F)-F (1-41) 4% 3-BB(F,F)XB(F)B(F,F)-F (1-42) 13% 1-BB-3 ( 2-3) 10% V-HHB-1 (2-9) 8% 1-BB(F)B-2V (2-12) 3% 2-BB(F)B-2V (2-12) 4% 3-BB(F)B-2V (2-12) 4% 5-HBB(F)B-2 (2-21) 6% 5-HBB(F)B-3 (2-21) 6% NI= 79.2℃; T _C <-20℃; η=39.2 mPa·s; Δn=0.179; Δε=13.2; Vth=1.46 V.

[Composition (M2)] 3-HB-C （1-1） 10% 3-HB(F)-C （1-1） 15% 3-HHB-F （1-9） 4% 2-HHB(F)-F （1-9） 11% 3-HHB(F)-F （1-9） 11% 5-HHB(F)-F （1-9） 10% 3-HHB(F)-C （1-9） 8% 3-BB(F,F)XB(F,F)-F （1-28） 1% 3-HB-O2 （2-2） 10% 3-HHB-1 （2-9） 8% 3-HHB-3 （2-9） 8% 3-HHB-O1 （2-9） 4% NI=95.5℃； _TC ＜-20℃；η=22.3 mPa·s；Δn=0.100；Δε=8.1；Vth=1.50 V.

[Composition (M3)] 2-HHB(F)-F (1-9) 12% 3-HHB(F)-F (1-9) 12% 5-HHB(F)-F (1-9) 11% 3-HHB(F,F)-F (1-9) 10% 3-HHXB(F,F)-F (1-13) 1% 2-HBB(F)-F (1-16) 4.5 % 3-HBB(F)-F (1-16) 4.5% 5-HBB(F)-F (1-16) 9% 3-HBB(F,F)-F (1-16) 18% 3- HB-O2 (2-2) 5% 3-HHB-1 (2-9) 8% 3-HHB-O1 (2-9) 5% NI=101.8℃; T _C <-20℃; η=24.5 mPa ·s; Δn=0.105; Δε=6.1; Vth=1.76 V.

[Composition (M4)] 3-BB(F,F)XB(F,F)-F (1-28) 15% 3-BB(F,F)XB(F,F)-F (1-42) 12% 3-HB-O2 (2-2) 15% 3-HHB-1 (2-9) 8% 3-HHB-3 (2-9) 10% 3-HHB-O1 (2-9) 5% 3-HBB-2 (2-10) 12% 2-BB(F)B-5 (2-12) 8% 3-BB(F)B-5 (2-12) 8% 3-BB(2F,5F)B-3 (2-13) 7% NI=100.5℃； _TC ＜-20℃；η=32.3 mPa·s; Δn=0.162; Δε=6.2; Vth=2.28 V.

[Composition (M5)] 3-HB-CL (1-1) 3% 5-HXB(F,F)-F (1-7) 3% 3-HHB-OCF3 (1-9) 3% 3-HHXB(F,F)-F (1-13) 6% 3-HGB(F,F)-F (1-14) 3% 3-HB(F)B(F,F)-F (1-17) 5% 3-BB(F,F)XB(F,F)-F (1-28) 6% 3-HHBB(F,F)-F (1-29) 6% 5-BB(F)B(F,F)XB(F)B(F,F)-F (1-43) 2% 3-BB(2F,3F)XB(F,F)-F (1-44) 4% 3-HHB(F,F)XB(F,F)-F （1） 4% 3-HBB(2F,3F)XB(F,F)-F （1） 5% 3-HH-V （2-1） 22% 3-HH-V1 （2-1） 10% 5-HB-O2 （2-2） 5% 3-HHEH-3 （2-8） 3% 3-HBB-2 （2-10） 7% 5-B(F)BB-3 （2-11） 3% NI=77.2℃； _TC ＜-20℃；Δn=0.101；Δε=5.8；Vth=1.88 V；η=13.7 mPa·s；γ1=61.3 mPa·s.

The polymerizable compound is suitably selected and used from the following compounds.

The following optically active compounds were used in the examples.

[Example 1] (1) Preparation of a liquid crystal dimming element The composition (M1) has a positive dielectric anisotropy. Based on the composition (M1), an optically active compound (10-4-1) is added at a ratio of 1.0%. The helical pitch is 1.1 μm. A polymerizable compound (RM-15) is mixed with the composition to prepare a polymerizable composition. The ratio is set to polymerizable compound (RM-15)/composition (M1) = 6%/94%. Based on the polymerizable compound, Irgacure 651 (photopolymerization initiator; registered trademark; BASF) is added at a ratio of 5.0%. The polymerizable composition is injected into an element in which the interval (unit gap) between two glass substrates is 10 μm. No alignment treatment is performed in the element. While applying 30 V (60 Hz) to the element, 18 mW/ ^cm2 ultraviolet light was irradiated for 56 seconds using a high-pressure mercury lamp to produce an element having a liquid crystal composite. The element was opaque. When a voltage of 30 V was applied to the element and light was irradiated, it became transparent. From this result, it can be seen that the element is in normal mode.

(2) Haze change rate The element is placed in the haze meter in such a way that the element is perpendicular to the incident light. A voltage in the range of 0 V to 60 V is applied to this element, and the haze rate is measured. Next, the haze rate after the weather resistance test performed under the conditions described in measurement (22) was measured. It was 95.9% before the test and 88.6% after the test. The haze change rate is 7.3%.

[Example 2] (1) Preparation of a liquid crystal dimming element The composition (M2) has a positive dielectric anisotropy. Based on the composition (M2), an optically active compound (10-4-1) is added at a ratio of 0.94%. The helical pitch is 1.0 μm. A polymerizable composition is prepared by mixing a polymerizable compound (RM-1) and a polymerizable compound (RM-5) in the composition. The ratio is set to polymerizable compound (RM-1)/polymerizable compound (RM-5)/composition (M2) = 32%/8%/60%. Based on the mixture of polymerizable compounds, Irgacure 651 (photopolymerization initiator; registered trademark; BASF) is added at a ratio of 0.75%. The polymerizable composition is injected into an element having a spacing (unit gap) of 10 μm between two glass substrates. No alignment treatment is performed in the element. While applying 30 V (60 Hz) to the element, 18 mW/ ^cm2 ultraviolet light was irradiated for 56 seconds using a high-pressure mercury lamp to produce an element having a liquid crystal composite. The element was opaque. When a voltage of 30 V was applied to the element and light was irradiated, it became transparent. From this result, it can be seen that the element is in normal mode.

(2) Haze change rate The haze rate before and after the weather resistance test was measured using the same method as Example 1, and the haze change rate was calculated. The haze change rate is 4.2%.

[Example 3 to Example 5] The haze change rate was calculated using the same method as in Example 2. The results are summarized in Table 4. In Example 3 to Example 5, the optically active compound (10-4-1) was added at a ratio of 1.0% based on the composition. [Table 4] Preparation of Liquid Crystal Dimming Element Embodiment Polymeric composition Liquid crystal dimming element Composition (60%) Polymeric compounds No voltage applied Apply voltage Fog change rate (%) (32%) (8%) 2 M2 RM-1 RM-5 opaque transparent 4.2 (87.4-83.2) 3 M3 RM-1 RM-8 opaque transparent 7.1 (86.2-79.1) 4 M4 RM-2 RM-8 opaque transparent 8.5 (93.6-85.1) 5 M5 RM-2 RM-6 opaque transparent 8.2 (83.8-75.6)

From the above results, it can be seen that the elements of Examples 1 to 5 have normal mode. For these components, the weather resistance test described in Japanese Industrial Standards (JIS) was performed. The haze change rate before and after the test was less than 10%. From this result, it can be seen that the liquid crystal dimming element has a small change with time. Therefore, we came to the conclusion that a liquid crystal composite composed of a combination of a specific chiral nematic composition and a specific polymer can be suitably used in a liquid crystal dimming element. [Industrial availability]

The liquid crystal dimming element containing the liquid crystal composite of the present invention can be used in dimming windows, smart windows, etc.

without

Figure 1 shows the dimming element in normal mode. Figure 2 shows a dimming element in reverse mode.

Claims (12)

A liquid crystal composite comprises a liquid crystal composition and a polymer, wherein the liquid crystal composition contains at least one compound selected from the compounds represented by formula (1) as component A and an optically active compound as additive A, wherein the polymer is derived from a precursor, wherein the main component of the precursor is at least one compound selected from the compounds represented by formula (4-3) to (4-5), formula (5), formula (6-2) to (6-6), formula (7), formula (8-2) to (8-6), formula (8-8) to (8-31) and formula (9), and the additive A is at least one optically active compound selected from the compounds represented by formula (10-4) to (10-6), wherein the proportion of the polymer based on the liquid crystal composite is in the range of 3% to 40%, and the proportion of the additive A based on the liquid crystal composition is in the range of 0.03% to 25%:

In formula (1), ^R1 is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; Ring A is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; ^Z1 is a single bond, ethylene, ethenylene, ethynylene, methyleneoxy, carbonyloxy, or difluoromethyleneoxy; ^X1 and ^X2 are hydrogen or fluorine; Y ¹ is fluorine, chlorine, cyano, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine, or an alkenyloxy group having 2 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine; a is 1, 2, 3 or 4; in formula (4-4), r is an integer from 1 to 15; in formula (5), M ⁴ and M ⁵ are hydrogen or methyl; Z ⁶ is an alkylene group having 21 to 80 carbon atoms, in which at least one hydrogen is substituted by an alkyl group having 1 to 20 carbon atoms, fluorine or chlorine, at least one -CH ₂ - is substituted by -O-, -CO-, -COO-, -OCO-, -NH- or -N(R ⁶ )-, and at least one -CH ₂ CH ₂ - is substituted by -CH=CH- or -C≡C-, wherein R ⁶ is an alkyl group having 1 to 12 carbon atoms, in which at least one -CH ₂ - may be substituted by -O-, -CO-, -COO- or -OCO-; in formula (6-2) to formula (6-5), R ¹³ and R ¹⁴ are alkyl groups having 3 to 10 carbon atoms, in which at least one -CH ₂ - may be substituted by -O-, -CO-, -COO- or -OCO-; in formula (7), ring G and ring I are 1,4-cyclohexylene, 1,4-phenylene, 1,4-cyclohexenyl, pyridine-2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene-2,6-diyl or fluorene-2,7-diyl, wherein at least one hydrogen may be substituted by fluorine, chlorine, cyano, hydroxyl, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbon atoms, alkoxy having 1 to 5 carbon atoms, alkoxycarbonyl having 2 to 5 carbon atoms or alkyl having 1 to 5 carbon atoms; Z ⁸ is a single bond, -O-, -COO-, -OCO- or -OCOO-; Z ⁹ is a single bond, -OCH ₂ -, -CH ₂ O-, -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=N- or -C≡C-; ^Y2 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 2 to 20 carbon atoms; f is an integer from 1 to 4; e is an integer from 0 to 20; M ⁷ is hydrogen or methyl; in formula (8-2) to formula (8-6) and formula (8-8) to formula (8-31), M ⁸ and M ⁹ are hydrogen or methyl; g and i are integers from 1 to 20; in formula (9), ring L and ring M are 1,4-cyclohexyl, 1,4-phenylene, 1,4-cyclohexenyl, pyridine-2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene-2,6-diyl or fluorene-2,7-diyl, wherein at least one hydrogen may be substituted by fluorine, chlorine, cyano, hydroxyl, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbon atoms, alkoxy having 1 to 5 carbon atoms, alkoxycarbonyl having 2 to 5 carbon atoms or alkyl having 1 to 5 carbon atoms; Z ¹³ and Z Z ¹⁷ is a single bond, -O-, -COO-, -OCO- or -OCOO-; Z ¹⁴ and Z ¹⁶ are a single bond, -OCH ₂ -, -CH ₂ O-, -COO-, -OCO-, -COS-, -SCO-, -OCOO-, -CONH-, -NHCO-, -CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CF ₂ CF ₂ -, -CH=CHCOO-, -OCOCH=CH-, -CH ₂ CH ₂ COO-, -OCOCH ₂ CH ₂ -, -CH=CH-, -N=CH-, -CH=N-, -N=C(CH ₃ )-, -C(CH ₃ )=N-, -N=N- or -C≡C-; Z wherein R ¹¹ to R ¹⁵ are hydrogen, fluorine, chlorine, cyano, -SF ⁵ or an alkyl group having 1 to 10 carbon atoms, wherein at least ^one -CH ² - in the alkyl group may be substituted by -O-, _-COO- or -OCO-, and at least _{one -CH 2 CH 2} - may be substituted by -CH=CH- or -C≡C-, in which at least one hydrogen atom may be substituted by fluorine or chlorine; Ring T, Ring U, Ring X, Ring Y and Ring Z are 1,4-cyclohexylene, 1,4-phenylene, 1,3-dioxane-2,5-diyl, tetrahydropyran-2,5-diyl, tetrahydropyran-3,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl or bicyclo[2.2.2]octane-1,4-diyl, in which at least one hydrogen atom may be substituted by fluorine or chlorine; Ring R, Ring S, Ring V and Ring W are 5,6,7,8-tetrahydronaphthalene-1,2-diyl or naphthalene-1,2-diyl; Z ²¹ to Z ²⁵ is a single bond or an alkylene group having 1 to 20 carbon atoms, in which at least one -CH ₂ - may be substituted by -O-, -CO-, -COO- or -OCO-, at least one -CH ₂ CH ₂ - may be substituted by -CH=CH- or -C≡C-, and in which at least one hydrogen may be substituted by fluorine or chlorine; s, t, u, v and w are 1, 2 or 3. The liquid crystal composite according to claim 1, wherein the liquid crystal composition contains as component A at least one compound selected from the compounds represented by formula (1-1) to formula (1-47):

In Formula (1-1) to Formula (1-47), R ¹ is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms, and X ¹ and X ² is hydrogen or fluorine; Y ¹ is fluorine, chlorine, cyano, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine Oxy group, or an alkenyloxy group having 2 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine. The liquid crystal composite as described in claim 1, wherein the proportion of component A is in the range of 5% to 90% based on the liquid crystal composition. The liquid crystal composite according to claim 1, wherein the liquid crystal composition contains, as component B, at least one compound selected from the compounds represented by formula (2):

In formula (2), ^R2 and ^R3 are alkyl having 1 to 12 carbon atoms, alkoxy having 1 to 12 carbon atoms, alkenyl having 2 to 12 carbon atoms, or alkenyl having 2 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine; Ring B and Ring C are 1,4-cyclohexyl, 1,3-phenylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene or pyrimidine-2,5-diyl; ^Z2 is a single bond, ethylene, ethenylene, ethynylene, methyleneoxy or carbonyloxy; and b is 1, 2 or 3. The liquid crystal composite according to claim 1, wherein the liquid crystal composition contains as component B at least one compound selected from the compounds represented by formula (2-1) to formula (2-23):

In Formula (2-1) to Formula (2-23), R ² and R ³ are 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, or Alkenyl group having 2 to 12 carbon atoms in which at least one hydrogen is substituted by fluorine or chlorine. The liquid crystal composite according to claim 1, wherein the liquid crystal composition contains, as component C, at least one compound selected from the compounds represented by formula (3):

In formula (3), ^R4 and ^R5 are hydrogen, 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, or an alkenyloxy group having 2 to 12 carbon atoms; Ring D and Ring F are 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene in which at least one hydrogen atom is substituted with fluorine or chlorine, naphthalene-2,6-diyl, naphthalene-2,6-diyl in which at least one hydrogen atom is substituted with fluorine or chlorine, chromane-2,6-diyl, or chromane-2,6-diyl in which at least one hydrogen atom is substituted with fluorine or chlorine. ,6-diyl; Ring E 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; Z ³ and Z ⁴ are a single bond, ethylene, ethenylene, methyleneoxy or carbonyloxy; c is 0, 1, 2 or 3, d is 0 or 1, and the sum of c and d is 3 or less. The liquid crystal composite according to claim 1, wherein the liquid crystal composition contains, as component C, at least one compound selected from the compounds represented by formula (3-1) to formula (3-35):

In formula (3-1) to formula (3-35), ^R4 and ^R5 are hydrogen, 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, or an alkenyloxy group having 2 to 12 carbon atoms. The liquid crystal composite as described in claim 1, wherein the helical pitch of the liquid crystal composition is less than 10 μm. The liquid crystal composite as described in claim 1, wherein the liquid crystal composition contains a dichroic pigment as additive B. A liquid crystal light modulating element, wherein the light modulating layer is the liquid crystal composite according to claim 1, and the light modulating layer is sandwiched by a pair of transparent substrates, and the transparent substrates have transparent electrodes. A dimming window using the liquid crystal dimming element as described in claim 10. A smart window using the liquid crystal dimming element as described in claim 10.