Liquid crystal composition, liquid crystal display element, and use of liquid crystal composition in liquid crystal display element

Abstract

The present invention provides a liquid crystal composition and an AM element comprising the composition. The liquid crystal composition sufficiently satisfies at least one of the characteristics of a high upper limit temperature, a low lower limit temperature, a small viscosity, a suitable optical anisotropy, a large dielectric anisotropy, a large dielectric constant in the short-axis direction, a large ratio of the dielectric constant in the short-axis direction to the dielectric anisotropy, a large specific resistance, high stability to light and heat, a large elastic constant, etc., or exhibits a proper balance between at least two of the characteristics. A liquid crystal composition comprises a specific compound having a large optical anisotropy as a component A, and may further comprise a specific compound having a large dielectric anisotropy as a component B, a specific compound having a small viscosity or a high upper limit temperature as a component C, or a specific compound having a large dielectric constant in the short-axis direction as a component D.

Description

Liquid crystal compositions, liquid crystal display elements, and uses of liquid crystal compositions in liquid crystal display elements Technical Field

[0001] This invention relates to a liquid crystal composition, a liquid crystal display element containing the composition, and the like. In particular, it relates to a liquid crystal composition with positive dielectric anisotropy, and an active matrix (AM) element containing the composition and having a TN, ECB, OCB, IPS, FFS, or FPA mode. Background Technology

[0002] In liquid crystal display (LCD) elements, classification based on the operating mode of liquid crystal molecules includes phase change (PC), twisted nematic (TN), super twisted nematic (STN), electrically controlled birefringence (ECB), optically compensated bend (OCB), in-plane switching (IPS), vertical alignment (VA), fringe field switching (FFS), and field-induced photo-reactive alignment (FPA). Classification based on the driving method of the element includes passive matrix (PM) and active matrix (AM). PM is further classified into static and multiplex types, while AM ​​is classified into thin-film transistor (TFT) and metal-insulator-metal (MIM) types. TFTs are classified into amorphous silicon and polycrystalline silicon. The latter is classified into high-temperature type and low-temperature type based on the manufacturing process. Based on the light source, it is classified into reflective type that uses natural light, transmissive type that uses backlight, and semi-transmissive type that uses both natural light and backlight.

[0003] Liquid crystal display elements contain a liquid crystal composition having a nematic phase. This composition possesses suitable properties. By improving the properties of this composition, AM elements with good properties can be obtained. The correlation among these properties is summarized in Table 1 below. The properties of the composition are further explained based on commercially available AM ​​elements. 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 about 70°C or higher, and the preferred lower limit temperature of the nematic phase is about -10°C or lower. The viscosity of the composition is related to the response time of the element. For displaying moving images on the element, a short response time is preferred. Ideally, a response time shorter than 1 millisecond is desired. Therefore, a low viscosity of the composition is preferred. Furthermore, a low viscosity at low temperatures is preferred. The elastic constant of the composition is related to the contrast ratio of the element. In the element, for improving contrast ratio, a high elastic constant of the composition is preferred.

[0004] Table 1. Properties of the composition and properties of the AM element

[0005] The optical anisotropy of the composition is related to the contrast ratio of the element. Depending on the element mode, a large or small optical anisotropy, i.e., an appropriate optical anisotropy, is required. The product (Δn×d) of the optical anisotropy of the composition (Δn) and the cell gap (d) of the element is designed to maximize the contrast ratio. The appropriate value of the product depends on the type of operating mode. In elements with modes such as TN, an appropriate value is about 0.45 μm. In this case, a composition with a large optical anisotropy is preferred for elements with a small cell gap. A large dielectric anisotropy of the composition helps to result in a low critical voltage, low power consumption, and high contrast ratio of the element. Therefore, a large dielectric anisotropy is preferred. Dielectric anisotropy is generally frequency-dependent at low temperatures, decreasing as the frequency increases. Therefore, at low temperatures, as the driving frequency increases, the movement of liquid crystal molecules cannot keep up with the frequency changes of the voltage, causing display defects. Therefore, the frequency dependence of dielectric anisotropy at low temperatures should be small. A high resistivity of the composition contributes to a high voltage retention rate and high contrast ratio of the element. Therefore, a composition with a high resistivity in the initial stage is preferred. A composition that retains a high resistivity even after prolonged use is also preferred. The stability of the composition against ultraviolet light and heat is related to the lifespan of the liquid crystal display element. Higher stability results in a longer lifespan for the element. This characteristic is preferred for AM elements used in LCD monitors, LCD televisions, etc.

[0006] Compositions with positive dielectric anisotropy are used in AM elements with TN mode. Compositions with negative dielectric anisotropy are used in AM elements with VA mode. Compositions with either positive or negative dielectric anisotropy are used in polymer sustained alignment (PSA) type AM elements.

[0007] In liquid crystal display elements that display moving images, it is desirable to shorten the response time. Therefore, there is a need for a liquid crystal composition with low viscosity without compromising the temperature range, optical anisotropy, or dielectric anisotropy of the nematic phase.

[0008] In the case of compositions with positive dielectric anisotropy, a shorter response time is particularly desirable. Theoretically, it is known that if the cell gap (d) of the element is narrowed, the response time becomes shorter. In this case, to optimize the product (Δn×d), a liquid crystal composition with relatively high optical anisotropy (Δn) is required. However, generally speaking, liquid crystal compositions with relatively high optical anisotropy (Δn) have relatively high viscosity. Therefore, even if the cell gap is narrowed, it is difficult to improve the response time. Therefore, a liquid crystal composition with both high optical anisotropy and low viscosity is sought.

[0009] To meet the required properties of liquid crystal display elements as described above, various compounds have been studied. In recent years, liquid crystal compositions containing thiophene derivatives or benzothiophene derivatives have been developed (Patent Document 1 and Patent Document 2, etc.). However, these liquid crystal compositions do not adequately achieve a balance between high optical anisotropy and low viscosity, and a composition with an even better balance of properties is sought.

[0010] [Existing Technical Documents]

[0011] [Patent Literature]

[0012] [Patent Document 1] Japanese Patent Application Publication No. 2021-165367

[0013] [Patent Document 2] International Publication No. 2016 / 132998 Summary of the Invention

[0014] [The technical problem that this invention aims to solve]

[0015] The technical problem of the present invention is to provide a liquid crystal composition and a liquid crystal display element, wherein the liquid crystal composition satisfies at least one of the following characteristics: high upper limit temperature of the nematic phase, low lower limit temperature of the nematic phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, large dielectric constant (ε⊥) in the short axis direction, large ratio of dielectric constant to dielectric anisotropy (ε⊥ / Δε) in the short axis direction, large resistivity, high stability to light, high stability to heat, and large elastic constant; and the liquid crystal display element satisfies at least one of the following characteristics: short response time and low critical voltage. Another technical problem is to provide a liquid crystal composition that achieves a suitable balance between at least two of the following characteristics: high upper limit temperature of the nematic phase, low lower limit temperature of the nematic phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, large dielectric constant in the short axis direction, large ratio of dielectric constant in the short axis direction to dielectric anisotropy (ε⊥ / Δε), high resistivity, high stability to light, high stability to heat, and large elastic constant. Yet another technical problem is to provide an AM element with characteristics such as high voltage retention rate, high contrast ratio, and long lifetime.

[0016] [Methods for solving technical problems]

[0017] The present invention relates to a liquid crystal composition, a liquid crystal display element containing the composition, and the use of the liquid crystal composition in a liquid crystal display element, wherein the liquid crystal composition contains at least one compound selected from the compounds represented by formula (1) as component A and has positive dielectric anisotropy.

[0018] In equation (1), R 1 and R 2 It is an alkyl group having 1 to 12 carbon atoms, wherein at least one -CH2- can be substituted with -O- or -S-, and at least one -(CH2)2- can be substituted with -CH=CH-, wherein at least one hydrogen atom can be substituted with a halogen; ring A 1 It is 1,4-cyclohexene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which at least one hydrogen atom is substituted by fluorine or chlorine; Z 1 For single bonds, -(CH2)2-, -CH=CH-, -CF=CF-, -C≡C-, -COO-, -OCO-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -(CH2)4-, -(CH2)2CF2O-, -(CH2)2OCF2-, -CF2O(CH2)2-, -OCF2(CH2)2-, -CH=CH-(CH2)2- or -(CH2)2-CH=CH-; a is 1, 2 or 3.

[0019] [The effects of the invention]

[0020] The advantages of this invention are that it provides a liquid crystal composition and a liquid crystal display element, wherein the liquid crystal composition satisfies at least one of the following characteristics: high upper limit temperature of the nematic phase, low lower limit temperature of the nematic phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, large dielectric constant (ε⊥) in the short axis direction, large ratio of dielectric constant to dielectric anisotropy (ε⊥ / Δε) in the short axis direction, high resistivity, high light stability, high thermal stability, and large elastic constant; and the liquid crystal display element satisfies at least one of the following characteristics: short response time and low critical voltage. Another advantage is that it provides a liquid crystal composition that achieves an appropriate balance between at least two of the following characteristics: high upper limit temperature of the nematic phase, low lower limit temperature of the nematic phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, large dielectric constant in the short axis direction, large ratio of dielectric constant to dielectric anisotropy (ε⊥ / Δε) in the short axis direction, high resistivity, high light stability, high thermal stability, and large elastic constant. Another advantage is that it provides an AM element with characteristics such as high voltage retention, high contrast, and long life. Detailed Implementation

[0021] The usage of terms in this specification is as follows. Sometimes, the terms "liquid crystal composition" and "liquid crystal display element" are abbreviated as "composition" and "element," respectively. "Liquid crystal display element" is a general term for liquid crystal display panels and liquid crystal display modules. "Liquid crystal compound" is a general term for compounds having a liquid crystal phase such as a nematic or laminamatic phase, as well as compounds that, although not having a liquid crystal phase, are mixed in the composition for the purpose of adjusting the temperature range, viscosity, dielectric anisotropy, and other properties of the nematic phase. This compound has, for example, a six-membered ring such as 1,4-cyclohexylene or 1,4-phenylene, and its molecules (liquid crystal molecules) are rod-like. "Polymerizable compound" is a compound added for the purpose of forming a polymer in the composition. Liquid crystal compounds containing alkenyl groups are not classified as polymerizable compounds in this sense.

[0022] Liquid crystal compositions are prepared by mixing various liquid crystal compounds. Additives such as optically active compounds or polymerizable compounds are added to the liquid crystal composition as needed. Even when additives are added, the proportion of the liquid crystal compound is expressed as a mass percentage (mass %) based on the mass of the liquid crystal composition excluding the additive. The proportion of the additive is expressed as a mass percentage (mass %) based on the mass of the liquid crystal composition excluding the additive. That is, the proportion of liquid crystal compound or additive is calculated based on the total mass of the liquid crystal compound. The proportions of polymerization initiators and polymerization inhibitors are exceptionally expressed based on the mass of the polymerizable compound.

[0023] Sometimes the "upper limit temperature of the nematic phase" is abbreviated as "upper limit temperature." Sometimes the "lower limit temperature of the nematic phase" is abbreviated as "lower limit temperature." The expression "improved dielectric anisotropy" means a positive increase in dielectric anisotropy for compositions with positive anisotropy, and a negative increase in dielectric anisotropy for compositions with negative anisotropy. "High voltage retention rate" means that the device maintains a high voltage retention rate not only at room temperature but also at temperatures close to the upper limit temperature in the initial stage, and continues to maintain a high voltage retention rate not only at room temperature but also at temperatures close to the upper limit temperature after prolonged use. Sometimes, time-varying tests are used to study the characteristics of compositions or devices.

[0024] Let's take compound (1z) as an example. In formula (1z), the codes for α and β, enclosed by hexagons, correspond to ring α and ring β, respectively, and represent six-membered rings, condensed rings, etc. When the subscript 'x' is 2, there are two rings α. The two groups represented by the two rings α can 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 codes such as bonding groups Z. The diagonal line that cuts across one side of ring β indicates that any hydrogen on ring β can be replaced by a substituent (-Sp-P). The subscript 'y' indicates the number of substituents. When the subscript 'y' is 0, this substitution does not exist. When the subscript 'y' is 2 or more, there are multiple substituents (-Sp-P) on ring β. In this case, the rule of "can be the same or different" also applies. Furthermore, this rule also applies when the code Ra is used in multiple compounds.

[0025] In formula (1z), for example, the statement "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. Here, the group represented by Ra and the group represented by Rb may be the same or different.

[0026] Sometimes, at least one compound selected from the compounds represented by formula (1z) is abbreviated 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 formulas. The statement "at least one compound selected from the compounds represented by formula (1z) and formula (2z)" means at least one compound selected from the group consisting of compounds (1z) and compounds (2z).

[0027] The statement "at least one 'A'" means that the number of 'A's is arbitrary. The statement "at least one 'A' can be replaced by 'B'" means that when there is only one 'A', the position of 'A' is arbitrary; when there are two or more 'A's, their positions can also be chosen without restriction. Sometimes the statement "at least one -CH2- can be replaced by -O-" is used. In this case, -CH2-CH2-CH2- can be converted to -O-CH2-O- by the substitution of a non-adjacent -CH2- with -O-. However, there is no case where an adjacent -CH2- is substituted by -O-. The reason is that -OO-CH2- (peroxide) is formed in this substitution.

[0028] The alkyl groups in liquid crystal compounds are either straight-chain or branched, and do not contain cyclic alkyl groups. Straight-chain alkyl groups are preferred over branched alkyl groups. The same applies to terminal groups such as alkoxy and alkenyl groups. Regarding the stereoconfiguration associated with 1,4-cyclohexene, the trans configuration is preferred over the cis configuration to increase the upper temperature limit. Because 2-fluoro-1,4-phenylene is asymmetrical, both left-facing (L) and right-facing (R) configurations exist.

[0029] The same applies to divalent groups such as tetrahydropyran-2,5-dimethyl. The same also applies to bonding groups such as carbonyloxy groups (-COO- or -OCO-).

[0030] The present invention includes the following items, etc.

[0031] Item 1. A liquid crystal composition comprising at least one compound selected from the compounds represented by formula (1) as component A and having positive dielectric anisotropy.

[0032] In equation (1), R 1 and R 2 It is an alkyl group having 1 to 12 carbon atoms, wherein at least one -CH2- can be substituted with -O- or -S-, and at least one -(CH2)2- can be substituted with -CH=CH-, wherein at least one hydrogen atom can be substituted with a halogen; ring A 1 It is 1,4-cyclohexene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which at least one hydrogen atom is substituted by fluorine or chlorine; Z 1For single bonds, -(CH2)2-, -CH=CH-, -CF=CF-, -C≡C-, -COO-, -OCO-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -(CH2)4-, -(CH2)2CF2O-, -(CH2)2OCF2-, -CF2O(CH2)2-, -OCF2(CH2)2-, -CH=CH-(CH2)2- or -(CH2)2-CH=CH-; a is 1, 2 or 3.

[0033] Item 2. The liquid crystal composition as described in Item 1, comprising at least one compound selected from the compounds represented by formulas (1-1) to (1-11) as component A.

[0034] In equations (1-1) to (1-11), R 1 It is an alkoxy group having 1 to 12 carbon atoms, an alkenyloxy group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine; R 2 It is 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.

[0035] Item 3. The liquid crystal composition as described in Item 1 or Item 2, wherein the proportion of component A is in the range of 1% by mass to 30% by mass.

[0036] Item 4. The liquid crystal composition as described in any one of Items 1 to 3, comprising at least one compound selected from the compounds represented by Formula (2) and Formula (3) as component B.

[0037] In equation (2), R 3 It 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 B is 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; Z 2 It is a single bond, ethylidene, vinylidene, carbonyloxy, or difluoromethyleneoxy; X 1 and X 2 It is hydrogen or fluorine; Y 1 It is fluorine, chlorine, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine, or an alkenyloxy group having 2 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine; b is 1, 2, 3 or 4.

[0038] In equation (3), R 4 It 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; the ring C is 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, or 1,3-dioxane-2,5-diyl; Z 3 It is a single bond, carbonyloxy group, or difluoromethyleneoxy group; X 3 and X 4 It is hydrogen or fluorine; c is 1, 2, 3 or 4.

[0039] Item 5. The liquid crystal composition as described in any one of Items 1 to 4, comprising at least one compound selected from the compounds represented by formulas (2-1) to (2-37) and (3-1) to (3-8) as component B.

[0040] In equations (2-1) to (2-37), R 3 It 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;

[0041] In equations (3-1) to (3-8), R 4 It 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; X 3 and X 4 It is either hydrogen or fluorine.

[0042] Item 6. The liquid crystal composition as described in Item 4 or Item 5, wherein the proportion of component B is in the range of 5% by mass to 50% by mass.

[0043] Item 7. The liquid crystal composition as described in any one of items 1 to 6, wherein at least one compound selected from the compounds represented by formula (4) is used as component C.

[0044] In equation (4), R 5 and R 6 It is 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 in which at least one hydrogen atom is substituted by fluorine or chlorine; ring D and ring E are 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene; Z 4It is a single bond, ethylidene, vinylidene, methyleneoxy, or carbonyloxy; d is 1, 2, or 3.

[0045] Item 8. The liquid crystal composition as described in any one of Items 1 to 7, comprising at least one compound selected from the compounds represented by formulas (4-1) to (4-16) as component C.

[0046] In equations (4-1) to (4-16), R 5 and R 6 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is replaced by fluorine or chlorine, or an alkenyl group having 2 to 12 carbon atoms in which at least one hydrogen atom is replaced by fluorine or chlorine.

[0047] Item 9. The liquid crystal composition as described in Item 7 or Item 8, wherein the proportion of component C is in the range of 10% by mass to 85% by mass.

[0048] Item 10. The liquid crystal composition as described in any one of items 1 to 9, comprising at least one compound selected from the compounds represented by formula (5) as component D.

[0049] In equation (5), R 7 and R 8 The alkyl group is 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, an alkenyloxy group having 2 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine; cyclic F and cyclic I are 1,4-cyclohexene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene in which at least one hydrogen atom is substituted by fluorine or chlorine, naphth-2,6-diyl, naphth-2,6-diyl in which at least one hydrogen atom is substituted by fluorine or chlorine, chromoline-2,6-diyl, or an alkyl group having at least one hydrogen atom substituted by fluorine or chlorine. Chlorinated chromoproto-2,6-diyl; ring G is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 1,8-difluorophenanthrene-2,7-diyl, 3,4,5-trifluoronaphthio-2,6-diyl, 7,8-difluorochromoproto-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 5 and Z 6It is a single bond, ethylidene, vinylidene, methyleneoxy, or carbonyloxy; e is 0, 1, 2, or 3, f is 0 or 1; and the sum of e and f is less than 3.

[0050] Item 11. The liquid crystal composition as described in any one of Items 1 to 10, comprising at least one compound selected from the compounds represented by formulas (5-1) to (5-36) as component D.

[0051] In equations (5-1) to (5-36), R 7 and R 8 It is 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, an alkenyloxy group having 2 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is replaced by fluorine or chlorine.

[0052] Item 12. The liquid crystal composition as described in Item 10 or Item 11, wherein the proportion of component D is in the range of 1% by mass to 20% by mass.

[0053] Item 13. A liquid crystal display element comprising a liquid crystal composition as described in any one of Items 1 to 12.

[0054] Item 14. The liquid crystal display element as described in Item 13, wherein the operating mode is TN mode, ECB mode, OCB mode, IPS mode, FFS mode or FPA mode, and the driving method is active matrix mode.

[0055] Item 15. Use of a liquid crystal composition, said liquid crystal composition being any one of items 1 to 12, in a liquid crystal display element.

[0056] The present invention also includes the following: (a) the composition comprising one, two, or three or more compounds selected from additives such as optically active compounds, antioxidants, UV absorbers, matting agents, pigments, defoamers, polymerizable compounds, polymerization initiators, polymerization inhibitors, and polar compounds. (b) an AM element comprising the composition. (c) the composition further comprising a polymerizable compound, and a polymer-stabilized alignment (PSA) type AM element comprising the composition. (d) a polymer-stabilized alignment (PSA) type AM element comprising the composition, wherein the polymerizable compound in the composition is polymerized. (e) an element comprising the composition and having a PC, TN, STN, ECB, OCB, IPS, VA, FFS, or FPA pattern. (f) a transmissive element comprising the composition. (g) use of the composition as a composition having a nematic phase. (h) use of an optically active composition obtained by adding an optically active compound to the composition.

[0057] The compositions of the present invention will be described in the following order: First, the composition structure will be described. Second, the main characteristics of the component compounds and the main effects of the compounds on the composition or element will be described. Third, the combination of component compounds in the composition, the preferred proportions, and the basis thereof will be described. Fourth, the preferred forms of the component compounds will be described. Fifth, preferred component compounds will be shown. Sixth, additives that can be added to the composition will be described. Seventh, the synthesis method of the component compounds will be described. Finally, the use of the composition will be described.

[0058] First, the composition of the composition will be described. 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, defoamers, polymerizable compounds, polymerization initiators, polymerization inhibitors, polar compounds, etc. From the viewpoint of liquid crystal compounds, the composition is classified as composition A and composition B. In addition to containing liquid crystal compounds selected from compounds (1), (2), (3), (4), and (5), composition A may also contain other liquid crystal compounds, additives, etc. "Other liquid crystal compounds" are liquid crystal compounds that are different from compounds (1), (2), (3), (4), and (5). Such compounds are mixed into the composition for the purpose of further adjusting the properties.

[0059] Composition B substantially contains only liquid crystal compounds selected from compounds (1), (2), (3), (4), and (5). "Substantially" means that composition B may contain additives but not other liquid crystal compounds. Compared to composition A, composition B has fewer components. From a cost reduction perspective, composition B is superior to composition A. From the perspective that properties can be further adjusted by mixing with other liquid crystal compounds, composition A is superior to composition B.

[0060] Second, the main characteristics of the component compounds and their main effects on the composition or component are described. The main characteristics of the component compounds are summarized in Table 2. In the codes of Table 2, L indicates large or high, M indicates moderate, and S indicates small or low. Codes L, M, and S are classifications based on qualitative comparisons between the component compounds, and code 0 (zero) indicates less than S.

[0061] Table 2. Properties of liquid crystal compounds

[0062] 1) The value of dielectric anisotropy is negative, and the code represents the magnitude of the absolute value.

[0063] The main effects of the component compounds are as follows. Compound (1) reduces viscosity, improves optical anisotropy, improves dielectric anisotropy, and increases the upper temperature limit. Compounds (2) and (3) improve dielectric anisotropy. Compound (4) reduces viscosity or increases the upper temperature limit. Compound (5) increases the dielectric constant along the short axis.

[0064] Third, the combination of component compounds in the composition, the preferred ratio, and the basis thereof are explained. Preferred combinations of component compounds in the composition are compound (1) + compound (2) + compound (4), compound (1) + compound (2) + compound (5), compound (1) + compound (3) + compound (4), compound (1) + compound (3) + compound (5), compound (1) + compound (2) + compound (3) + compound (4), compound (1) + compound (2) + compound (3) + compound (5), compound (1) + compound (2) + compound (4) + compound (5), or compound (1) + compound (2) + compound (3) + compound (4) + compound (5). Particularly preferred combinations are compound (1) + compound (2) + compound (4), compound (1) + compound (2) + compound (3) + compound (4), or compound (1) + compound (2) + compound (4) + compound (5).

[0065] To improve optical anisotropy and upper limit temperature, the preferred proportion of compound (1) is about 1% by mass or more, and to lower the lower limit temperature, the preferred proportion of compound (1) is about 30% by mass or less. Further, the preferred proportion is in the range of about 3% by mass to about 20% by mass. The particularly preferred proportion is in the range of about 3% by mass to about 15% by mass.

[0066] To improve dielectric anisotropy, the preferred proportion of component B is about 5% by mass or more; to lower the lower limit temperature, the preferred proportion of component B is about 50% by mass or less. Further, the preferred proportion is in the range of about 10% by mass to about 40% by mass. Particularly preferred is the range of about 10% by mass to about 30% by mass.

[0067] To reduce viscosity or increase the upper temperature limit, the preferred proportion of compound (4) is about 10% by mass or more, and to improve dielectric anisotropy, the preferred proportion of compound (4) is about 85% by mass or less. Further, the preferred proportion is in the range of about 20% by mass to about 85% by mass. Particularly preferred is in the range of about 40% by mass to about 80% by mass.

[0068] To increase the dielectric constant in the short axis direction, the preferred proportion of compound (5) is about 1% by mass or more, and to lower the lower limit temperature, the preferred proportion of compound (5) is about 20% by mass or less. More preferably, the proportion is in the range of about 5% by mass to about 20% by mass. Particularly preferred, the proportion is in the range of about 5% by mass to about 15% by mass.

[0069] Fourth, the preferred forms of the component compounds are described. In formulas (1), (2), (3), (4), and (5), R 1 and R 2 It is an alkyl group having 1 to 12 carbon atoms, wherein at least one -CH2- can be substituted with -O- or -S-, and at least one -(CH2)2- can be substituted with -CH=CH-, wherein at least one hydrogen atom can be substituted with a halogen. To improve optical anisotropy, a preferred R... 1 It is an alkoxy group having 1 to 12 carbon atoms, an alkenyloxy group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms whose at least one hydrogen atom is substituted by fluorine or chlorine. Especially desirable is R. 1 It is an alkoxy group with 1 to 12 carbon atoms. For improved stability, a preferred R... 2 It is 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 best R... 2 It is an alkyl group having 1 to 12 carbon atoms. R 3 It 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. For improved stability, R is preferred. 3It is an alkyl group having 1 to 12 carbon atoms. R 4 It 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. For improved stability, R is preferred. 4 For alkyl groups having 1 to 12 carbon atoms, R is preferred to reduce viscosity. 4 It is an alkenyl group with 2 to 12 carbon atoms. 5 and R 6 It is 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 in which at least one hydrogen atom is substituted by fluorine or chlorine. For improved stability, R is preferred. 5 Or R 6 For alkyl groups having 1 to 12 carbon atoms, R is preferred to reduce viscosity. 5 Or R 6 It is an alkenyl group with 2 to 12 carbon atoms. 7 and R 8 It is 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, an alkenyloxy group having 2 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine. For improved stability, R is preferred. 7 Or R 8 For alkyl groups having 1 to 12 carbon atoms, R is preferred to reduce viscosity. 7 Or R 8 For alkenyl groups with 2 to 12 carbon atoms, a preferred R is used to improve the dielectric constant along the short axis. 7 Or R 8 It is an alkoxy group with 1 to 12 carbon atoms.

[0070] Preferred alkyl groups are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or octyl. Furthermore, to reduce viscosity, preferred alkyl groups are methyl, ethyl, propyl, butyl, or pentyl.

[0071] Preferred alkoxy groups are methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy, or heptoxy. Furthermore, to reduce viscosity, methoxy or ethoxy groups are preferred.

[0072] 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. To reduce viscosity, further preferred alkenyl groups are vinyl, 1-propenyl, 3-butenyl, or 3-pentenyl. The preferred stereoconfiguration of the -CH=CH- group in these alkenyl groups depends on the position of the double bond. For the purpose of reducing viscosity, etc., the trans configuration is preferred among alkenyl groups such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, 3-pentenyl, and 3-hexenyl. The cis configuration is preferred among alkenyl groups such as 2-butenyl, 2-pentenyl, and 2-hexenyl.

[0073] Preferred alkenyloxy groups are vinyloxy, allyloxy, 3-butenyloxy, 3-pentenyloxy, or 4-pentenyloxy. Furthermore, to reduce viscosity, allyloxy or 3-butenyloxy are preferred alkenyloxy groups.

[0074] Preferred examples of alkyl groups in which at least one hydrogen atom is substituted by fluorine or chlorine are fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, 5-fluoropentyl, 6-fluorohexyl, 7-fluoroheptyl, or 8-fluorooctyl. Further preferred examples for reducing viscosity are fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, or 5-fluoropentyl.

[0075] Preferred examples of an alkenyl group in which at least one hydrogen atom is substituted by fluorine or chlorine are 2,2-difluorovinyl, 3,3-difluoro-2-propenyl, 4,4-difluoro-3-butenyl, 5,5-difluoro-4-pentenyl, or 6,6-difluoro-5-hexenyl. For reducing viscosity, 2,2-difluorovinyl or 4,4-difluoro-3-butenyl are even more preferred examples.

[0076] Ring A 1 It is 1,4-cyclohexene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which at least one hydrogen atom is substituted by fluorine or chlorine. To increase the upper temperature limit, cyclic A is preferred. 1 For 1,4-cyclohexylene, a preferred ring A is preferred to reduce viscosity or improve optical anisotropy. 1 For 1,4-phenylene, to improve dielectric anisotropy, a preferred ring A is... 1 It is a 1,4-phenylene oxide in which at least one hydrogen atom is substituted by fluorine or chlorine.

[0077] Ring B is 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl. To increase the upper temperature limit, ring B is preferably 1,4-cyclohexene; to improve optical anisotropy, ring B is preferably 1,4-phenylene; and to improve dielectric anisotropy, ring B is preferably 2,6-difluoro-1,4-phenylene. Tetrahydropyran-2,5-diyl is:

[0078] The preferred option is:

[0079] The ring C is 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, or 1,3-dioxane-2,5-diyl. To increase the upper temperature limit, the ring C is preferably 1,4-cyclohexene; to improve optical anisotropy, the ring C is preferably 1,4-phenylene; and to improve dielectric anisotropy, the ring C is preferably 2-fluoro-1,4-phenylene or 2,6-difluoro-1,4-phenylene.

[0080] Ring D and ring E are 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene. To reduce viscosity or to increase the upper temperature limit, ring D or ring E is preferably 1,4-cyclohexene; to improve optical anisotropy or to lower the lower temperature limit, ring D or ring E is preferably 1,4-phenylene or 2-fluoro-1,4-phenylene.

[0081] Ring F and ring I are 1,4-cyclohexene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene with at least one hydrogen substituted by fluorine or chlorine, naphth-2,6-diyl, naphth-2,6-diyl with at least one hydrogen substituted by fluorine or chlorine, chromoline-2,6-diyl, or chromoline-2,6-diyl with at least one hydrogen substituted by fluorine or chlorine. Preferred examples of "1,4-phenylene with at least one hydrogen substituted by fluorine or chlorine" are 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, or 2-chloro-3-fluoro-1,4-phenylene. To reduce viscosity, ring F or ring I is preferably 1,4-cyclohexylene; to improve the dielectric constant along the short axis, ring F or ring I is preferably tetrahydropyran-2,5-diyl; and to improve optical anisotropy, ring F or ring I is preferably 1,4-phenylene. The tetrahydropyran-2,5-diyl group in ring F or ring I is:

[0082] The preferred option is:

[0083] Ring G is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 1,8-difluorophenanthrene-2,7-diyl, 3,4,5-trifluoronaphthyl-2,6-diyl, 7,8-difluorochrome-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-tetrafluoroindane-2,5-diyl (InF4).

[0084] To reduce viscosity, the preferred ring G is 2,3-difluoro-1,4-phenylene, and to increase the dielectric constant in the short axis direction, the preferred ring G is 4,6-difluorodibenzothiophene-3,7-diyl.

[0085] Z 1 For single bonds, -(CH2)2-, -CH=CH-, -CF=CF-, -C≡C-, -COO-, -OCO-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -(CH2)4-, -(CH2)2CF2O-, -(CH2)2OCF2-, -CF2O(CH2)2-, -OCF2(CH2)2-, -CH=CH-(CH2)2-, or -(CH2)2-CH=CH-. To reduce viscosity, the preferred Z... 1 It is a single bond. Z 2 It can be a single bond, ethylene, vinylene, carbonyloxy, or difluoromethyleneoxy. For reducing viscosity, Z is preferred. 2 For single bonds, to improve dielectric anisotropy, the preferred Z-axis is... 2 It is a difluoromethyleneoxy group. Z 3 It is a single bond, carbonyl oxy group, or difluoromethylene oxy group. For reducing viscosity, Z is preferred. 3 For single bonds, to improve dielectric anisotropy, the preferred Z-axis is... 3 It is a carbonyloxy group or a difluoromethyleneoxy group. Z 4 It can be a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy. For reducing viscosity, Z is preferred. 4 It is a single bond. Z 5 and Z 6 It can be a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy. For reducing viscosity, Z is preferred. 5 or Z 6 For single bonds, to lower the lower limit temperature, the optimal Z... 5 or Z6 For ethylene, to improve the dielectric constant in the short axis direction, the preferred Z... 5 or Z 6 It is a methylene oxide.

[0086] Divalent groups such as methyleneoxy groups are asymmetrical. Among methyleneoxy groups, -CH2O- is preferred over -OCH2-. Among carbonyloxy groups, -COO- is preferred over -OCO-. Among difluoromethyleneoxy groups, -CF2O- is preferred over -OCF2-.

[0087] X 1 and X 2 It is either hydrogen or fluorine. To improve dielectric anisotropy, X is preferred. 1 or X 2 It is fluorine.

[0088] X 3 and X 4 It is either hydrogen or fluorine. To reduce viscosity or to improve optical anisotropy, X is preferred. 3 or X 4 For hydrogen, in order to improve dielectric anisotropy, the preferred X 3 or X 4 It is fluorine.

[0089] Y 1 It is fluorine, chlorine, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine, or an alkenyloxy group having 2 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine. For improving dielectric anisotropy, the preferred Y... 1 It is fluorine, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine, or an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine. A preferred example of an alkyl group having at least one hydrogen atom substituted by fluorine or chlorine is trifluoromethyl. A preferred example of an alkoxy group having at least one hydrogen atom substituted by fluorine or chlorine is trifluoromethoxy.

[0090] a is 1, 2, or 3. Preferably, a is 1 or 2 to improve optical anisotropy, increase the upper limit temperature, and decrease the lower limit temperature. b is 1, 2, 3, or 4. Preferably, b is 2 to reduce viscosity; preferably, b is 3 to increase the upper limit temperature or to improve dielectric anisotropy. c is 1, 2, 3, or 4. Preferably, c is 1 or 2 to decrease the lower limit temperature. d is 1, 2, or 3. Preferably, d is 1 to reduce viscosity; preferably, d is 2 or 3 to increase the upper limit temperature or to improve optical anisotropy. e is 0, 1, 2, or 3, f is 0 or 1, and the sum of e and f is 3 or less. Preferably, e is 0 or 1 to reduce viscosity; preferably, e is 2 to increase the upper limit temperature. Preferably, f is 0 to reduce viscosity; preferably, f is 1 to increase the upper limit temperature.

[0091] Fifth, preferred component compounds are shown. Preferred compound (1) is compounds (1-1) to (1-11) described in item 2. Among these compounds, in order to improve optical anisotropy or to increase the upper limit temperature, at least one of component A is preferably compound (1-7), compound (1-10) or compound (1-11).

[0092] Preferred compound (2) is compounds (2-1) to (2-37) as described in item 5. Among these compounds, at least one of component B is preferably compound (2-2), compound (2-6), compound (2-7), compound (2-14), compound (2-16), compound (2-17), compound (2-18), compound (2-20), compound (2-24), compound (2-25), compound (2-26), compound (2-28), compound (2-29), compound (2-31), or compound (2-32). To improve dielectric anisotropy, at least one of component B is further preferably compound (2-6), compound (2-16), compound (2-18), compound (2-20), compound (2-24), compound (2-25), compound (2-29), compound (2-31), or compound (2-32).

[0093] The preferred compound (3) is compounds (3-1) to (3-8) as described in item 5. Among these compounds, at least one of component B is preferably compound (3-1), compound (3-2), compound (3-3), compound (3-7), or compound (3-8). In order to reduce viscosity or to improve dielectric anisotropy, at least one of component B is preferably compound (3-1), compound (3-2), or compound (3-7).

[0094] The preferred compound (4) is compounds (4-1) to (4-16) as described in item 8. Among these compounds, at least one of component C is preferably compound (4-1), compound (4-3), compound (4-4), compound (4-7), compound (4-9), compound (4-11), or compound (4-13). In order to reduce viscosity, to increase the upper limit temperature, or to decrease the lower limit temperature, at least one of component C is preferably compound (4-1), compound (4-3), compound (4-7), or compound (4-11).

[0095] Preferred compound (5) is compounds (5-1) to (5-36) as described in item 11. Among these compounds, at least one of component D is preferably compound (5-1), compound (5-2), compound (5-3), compound (5-6), compound (5-8), compound (5-9), compound (5-10), compound (5-14), compound (5-19), or compound (5-36). To improve the dielectric constant in the short axis direction, at least one of component D is preferably compound (5-8) or compound (5-14).

[0096] Sixth, additives that can be added to the composition are described. Such additives include optically active compounds, antioxidants, ultraviolet absorbers, matting agents, pigments, defoamers, polymerizable compounds, polymerization initiators, polymerization inhibitors, polar compounds, etc. Optically active compounds are added to the composition to impart a torsion angle by inducing a helical structure in the liquid crystal molecules. Examples of such compounds are compounds (6-1) to (6-5). A preferred proportion of the optically active compound is about 5% by mass or less. A more preferred proportion is in the range of about 0.01% by mass to about 2% by mass.

[0097] To prevent a decrease in resistivity caused by heating in the atmosphere, or to maintain a high voltage retention rate not only at room temperature but also at temperatures close to the upper limit after prolonged use of the component, antioxidants such as compounds (7-1) to (7-3) may be added to the composition.

[0098] Compound (7-2) is effective in maintaining a high voltage retention rate not only at room temperature but also at temperatures close to the upper limit temperature after prolonged use of the component. To achieve this effect, the preferred proportion of the antioxidant is about 50 ppm or more, and to avoid lowering the upper limit temperature or raising the lower limit temperature, the preferred proportion of the antioxidant is about 600 ppm or less. More preferably, the proportion is in the range of about 100 ppm to about 300 ppm.

[0099] Preferred examples of ultraviolet absorbers include benzophenone derivatives, benzoic acid ester derivatives, triazole derivatives, etc. Preferred examples of triazole derivatives include compounds (8-1) to (8-6), etc. Additionally, light stabilizers such as sterically hindered amines are also preferred. Preferred examples of light stabilizers include compounds (9-1) to (9-16), etc. To obtain the aforementioned effect, the preferred proportion of these absorbers or stabilizers is about 50 ppm or more, and to avoid lowering the upper limit temperature or raising the lower limit temperature, the preferred proportion of these absorbers or stabilizers is about 10,000 ppm or less. More preferably, the proportion is in the range of about 100 ppm to about 10,000 ppm.

[0100] A matting agent is a compound that prevents the decomposition of a liquid crystal compound by accepting the light energy absorbed by the liquid crystal compound and converting it into heat energy. Preferred examples of matting agents are compounds (10⁻¹) to (10⁻⁷). To obtain the aforementioned effect, the preferred proportion of these matting agents is about 50 ppm or more, and to avoid raising the lower limit temperature, the preferred proportion of these matting agents is about 20,000 ppm or less. More preferably, the proportion is in the range of about 100 ppm to about 10,000 ppm.

[0101] To suit components in a guest-host (GH) mode, dichroic dyes such as azo dyes and anthraquinone dyes are added to the composition. The preferred proportion of the dye is in the range of about 0.01% by mass to about 10% by mass. To prevent foaming, defoamers such as dimethyl silicone oil and methylphenyl silicone oil are added to the composition. To achieve the desired effect, the preferred proportion of the defoamer is about 1 ppm or more; to prevent poor display, the preferred proportion of the defoamer is about 1000 ppm or less. More preferably, the proportion is in the range of about 1 ppm to about 500 ppm.

[0102] Polymerizable compounds are used to suit polymerically stable alignment (PSA) type components. Preferred examples of such polymerizable compounds include acrylates, methacrylates, vinyl compounds, vinyloxy compounds, propylene ethers, epoxy compounds (oxetane, oxetane), vinyl ketones, etc. Further preferred examples are derivatives of acrylates or methacrylates. Based on the total mass of the polymerizable compound, a preferred proportion is about 10% by mass or more. A further preferred proportion is about 50% by mass or more. A particularly preferred proportion is about 80% by mass or more. The most desirable proportion is 100% by mass.

[0103] To prevent polymerization, polymerization inhibitors may be added when storing polymerizable compounds. Polymerizable compounds are typically added to the composition with the polymerization inhibitors still attached. Examples of polymerization inhibitors include hydroquinone, hydroquinone derivatives such as methylhydroquinone, 4-tert-butylcatechol, 4-methoxyphenol, and phenothiazine.

[0104] Polar compounds are organic compounds that exhibit polarity. This excludes compounds with ionic bonds. Atoms such as oxygen, sulfur, and nitrogen are electronegative and tend to have a partial negative charge. Carbon and hydrogen are neutral or tend to have a partial positive charge. Polarity arises from the uneven distribution of partial charge among different types of atoms in the compound. For example, polar compounds have at least one partial structure such as -OH, -COOH, -SH, -NH2, >NH, >N-.

[0105] Seventh, the synthesis methods of the component compounds will be described. These compounds can be synthesized by known methods. Examples of synthesis methods are given. An example of the synthesis of compound (1) is described in Example 1. Compounds (2-20) are synthesized using the method described in Japanese Patent Application Publication No. 10-251186. Compounds (3-7) are synthesized using the method described in Japanese Patent Application Publication No. 10-114733. Compound (4-1) is synthesized using the method described in Japanese Patent Application Publication No. 9-77692. Compound (5-1) is synthesized using the method described in Japanese Patent Application Publication No. 2-503441. Antioxidants are commercially available. Compound (7-1) is available from Sigma-Aldrich Corporation. Compounds (7-2), etc., are synthesized using the method described in US Patent No. 3660505.

[0106] Compounds for which no synthetic method is described can be synthesized using methods described in publications such as *Organic Syntheses* (John Wiley & Sons, Inc.), *Organic Reactions* (John Wiley & Sons, Inc.), *Comprehensive Organic Synthesis* (Pergamon Press), and *New Lectures in Experimental Chemistry* (Maruzen). The composition is prepared from compounds obtained in the described manner using known methods. For example, the component compounds are mixed and then dissolved together by heating.

[0107] Finally, the uses of the composition are described. The composition primarily exhibits a lower limit temperature below about -10°C, an upper limit temperature above about 70°C, and an optical anisotropy in the range of about 0.07 to about 0.30. Devices containing this composition have a high voltage retention rate. This composition is suitable for AM devices. This composition is particularly suitable for transmissive AM devices. This composition can be used as a nematic composition and can be used as an optically active composition by adding optically active compounds.

[0108] This composition can be used in AM devices, and further in PM devices. It can be used in AM and PM devices with modes such as PC, TN, STN, ECB, OCB, IPS, FFS, VA, and FPA. It is particularly suitable for AM devices with TN, OCB, IPS, or FFS modes. In AM devices with IPS or FFS modes, the liquid crystal molecules can be aligned parallel or perpendicularly relative to the glass substrate when no voltage is applied. These devices can be reflective, transmissive, or semi-transmissive. Transmissive devices are preferred. It can also be used in amorphous silicon-TFT or polycrystalline silicon-TFT devices. This composition can also be used in nematic curvilinear aligned phase (NCAP) devices fabricated through microencapsulation or in polymer dispersed (PD) devices where a three-dimensional network of polymers is formed in the composition.

[0109] [Example]

[0110] The present invention will be further described in detail with reference to the embodiments. The present invention is not limited to these embodiments. The present invention includes mixtures of the composition of Example 1 and the composition of Example 2. The present invention also includes mixtures of at least two of the compositions of the examples. The synthesized compounds are identified by methods such as nuclear magnetic resonance (NMR) analysis. The properties of the compounds, compositions, and components are determined by the methods described below.

[0111] NMR analysis: A Bruker BioSpin DRX-500 was used for the determination. 1 In the H-NMR determination, the sample was dissolved in a deuterated solvent such as CDCl3, and the determination was performed at room temperature at 500 MHz with a cumulative count of 16. Tetramethylsilane was used as an internal standard. 19In F-NMR measurements, CFC13 was used as an internal standard, and the measurements were performed with a cumulative count of 24. In the description of nuclear magnetic resonance spectra, s refers to a singlet, d to a doublet, t to a triplet, q to a quartet, quintet, sextet, m to multiplet, and br to broad.

[0112] Gas chromatography analysis: A Shimadzu GC-14B gas chromatograph was used for the determination. Helium was used as the carrier gas (2 mL / min). The sample vaporization chamber was set to 280°C, and the detector (flame ionization detector, FID) was set to 300°C. For the separation of component compounds, an Agilent Technologies DB-1 capillary column (30 m in length, 0.32 mm in inner diameter, 0.25 μm in film thickness; dimethylpolysiloxane as the stationary phase; non-polar) was used. The column was held at 200°C for 2 minutes, then heated to 280°C at a rate of 5°C / min. The sample was prepared as an acetone solution (0.1% by mass), and 1 μL of this solution was injected into the sample vaporization chamber. The recorder was a Shimadzu C-R5A chromatography kit (Chromatopac) or equivalent. The obtained gas chromatography chromatograms show the retention time and area of ​​the peaks corresponding to the component compounds.

[0113] The solvent used to dilute the sample can be chloroform, hexane, etc. To separate the component compounds, the following capillary columns can be used: HP-1 (30m length, 0.32mm inner diameter, 0.25μm film thickness) manufactured by Agilent Technologies Inc., Rtx-1 (30m length, 0.32mm inner diameter, 0.25μm film thickness) manufactured by Restek Corporation, and BP-1 (30m length, 0.32mm inner diameter, 0.25μm film thickness) manufactured by SGE International Pty. Ltd., Australia. To prevent overlap of compound peaks, the Shimadzu CBP1-M50-025 capillary column (50m length, 0.25mm inner diameter, 0.25μm film thickness) can be used.

[0114] The proportion of liquid crystal compounds in the composition can be calculated using 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 chromatography pattern corresponds to the proportion of the liquid crystal compounds. When using the capillary column described above, the correction factor for each liquid crystal compound can be considered as 1. Therefore, the proportion of the liquid crystal compounds (mass%) can be calculated based on the area ratio of the peaks.

[0115] Test sample: When determining the properties of a composition or component, the composition is used directly as a test sample.

[0116] Measurement Methods: The characteristics were measured using the methods described below. These methods are mostly those described in the JEITA standard (JEITA·ED-2521B) reviewed and formulated by the Japan Electronics and Information Technology Industries Association (JEITA), or modified versions thereof. No thin-film transistors (TFTs) were installed in the TN element used for measurement.

[0117] (1) Upper limit temperature of nematic phase (NI; °C): The sample is placed on the heating plate of a melting point measuring apparatus equipped with a polarizing microscope and heated at a rate of 1 °C / min. The temperature at which a portion of the sample changes from a nematic phase to an isotropic liquid is measured. Sometimes the upper limit temperature of the nematic phase is abbreviated as "upper limit temperature".

[0118] (2) Lower limit temperature of nematic phase (T) C (℃): Place the sample containing the nematic phase in a glass bottle and store it in a freezer at 0℃, -10℃, -15℃, -20℃, -30℃, and -40℃ for 10 days, then observe the liquid crystal phase. For example, if the sample remains in the nematic phase at -20℃ and changes to a crystalline or lamellar phase at -30℃, then... C It is recorded as <-20℃. Sometimes the lower limit temperature of the nematic phase is abbreviated as "lower limit temperature".

[0119] (3) Viscosity (volume viscosity; η; measured at 20°C; mPa·s): The E-type rotational viscometer manufactured by Tokyo Keiki Co., Ltd. was used for the measurement.

[0120] (4) Viscosity (rotational viscosity; γ1; measured at 25°C; mPa·s): The method described in M. Imai et al., "Molecular Crystals and Liquid Crystals," Vol. 259, p. 37 (1995), was used. A sample was placed in a TN element with a torsion angle of 0° and a unit gap (cell gap) of 5 μm between the two glass substrates. A voltage was applied to the element in 0.5V increments within the range of 16V to 19.5V. After 0.2 seconds without voltage application, the voltage was repeatedly applied under conditions of applying only one rectangular wave (rectangular pulse; 0.2 seconds) and no voltage application (2 seconds). The peak current and peak time of the transient current generated by this application were measured. The value of rotational viscosity was obtained based on these measured values ​​and the calculation formula (10) described on p. 40 of M. Imai et al.'s paper. The required dielectric anisotropy value for this calculation is obtained using an element that measures the rotational viscosity and by the method described below.

[0121] (5) Optical anisotropy (refractive index anisotropy; Δn; measured at 25°C): Measurements were performed using light with a wavelength of 589 nm, employing an Abbe refractometer with a polarizing plate mounted on the eyepiece. The sample was dropped onto the main prism after rubbing its surface in one direction. The refractive index n∥ was measured when the direction of polarization was parallel to the direction of rubbing. The refractive index n⊥ was measured when the direction of polarization was perpendicular to the direction of rubbing. The value of optical anisotropy was calculated using the formula Δn = n∥ - n⊥.

[0122] (6) Dielectric anisotropy (Δε; measured at 25°C): A sample was placed in a TN element with a 9 μm gap (cell gap) between two glass substrates and a twist angle of 80 degrees. A sinusoidal wave (10V, 1kHz) was applied to the element, and the dielectric constant (ε∥) of the liquid crystal molecules along the long axis was measured after 2 seconds. A sinusoidal wave (0.5V, 1kHz) was applied to the element, and the dielectric constant (ε⊥) of the liquid crystal molecules along the short axis was measured after 2 seconds. The value of dielectric anisotropy was calculated using the formula Δε = ε∥ - ε⊥.

[0123] (7-1) Critical Voltage (Vth(25); measured at 25°C; V): An LCD5200 luminance meter manufactured by Otsuka Electronics Co., Ltd. was used for the measurement. The light source was a halogen lamp. The sample was placed in an FFS element with a spacing (unit gap) of 3.2 (μm) between two glass substrates. The voltage (32Hz, rectangular wave) applied to the element was increased stepwise from 0V to 10V in units of 0.01V. At this time, light was irradiated onto the element from the vertical direction, and the amount of light transmitted through the element was measured. A voltage-transmittance curve was prepared with the transmittance at the maximum of 100% and the transmittance at the minimum of 0%. The critical voltage is expressed as the voltage at which the transmittance becomes 90%.

[0124] (7-2) Critical voltage (Vth(-30); measured at -30℃; V): same as (7-1) except that it is measured at -30℃.

[0125] (8) Voltage Retention Rate (VHR-9; measured at 25°C; %): The TN element used for the measurement has a polyimide alignment film, and the spacing (unit gap) between the two glass substrates is 5 μm. The element is sealed with an adhesive that hardens by ultraviolet light after the sample is placed in it. The TN element is charged by applying a pulsed voltage (1V, 60 microseconds). The decaying voltage is measured over a period of 1000 milliseconds using a high-speed voltmeter, and the area A between the voltage curve per unit period and the horizontal axis is calculated. Area B is the area before decay. The voltage retention rate is expressed as a percentage of area A relative to area B.

[0126] (9) Voltage retention rate (VHR-10; measured at 60°C; %): The voltage retention rate was measured using the same procedure as described above, except that it was measured at 60°C instead of 25°C. The obtained value is expressed as VHR-10.

[0127] (10) Voltage Retention Rate (VHR-11; measured at 60°C; %): The voltage retention rate was measured after irradiation with ultraviolet light to evaluate the stability against ultraviolet light. The TN element used for the measurement had a polyimide alignment film and a unit spacing of 5 μm. The sample was injected into the element and irradiated with 5 mW / cm². 2 The UV light was applied for 167 minutes. The light source was a black light, F40T10 / BL (peak wavelength 369nm), manufactured by Eyegraphitics, Inc., with a spacing of 5mm between the element and the light source. In the VHR-11 measurement, the attenuation voltage was measured over a period of 1000 milliseconds. The composition with a large VHR-11 exhibits high stability against UV light.

[0128] (11) Voltage Retention Rate (VHR-12; determined at 60°C; %): The thermal stability was evaluated by measuring the voltage retention rate after heating the TN element containing the sample in a thermostat at 120°C for 20 hours. In the VHR-12 determination, the decaying voltage was measured over a period of 1000 milliseconds. Compositions with a large VHR-12 exhibit high thermal stability.

[0129] (12) Voltage Retention Rate (VHR-13; determined at 60°C; %): The thermal stability was evaluated by measuring the voltage retention rate after heating the TN element containing the sample in a thermostat at 100°C for three weeks. In the VHR-13 determination, the decaying voltage was measured over a period of 1000 milliseconds. Compositions with a large VHR-13 exhibit high thermal stability.

[0130] (13) Voltage Retention Rate (VHR-14; measured at 60°C; %): The voltage retention rate was measured after the TN element with the injected sample was placed on the backlight for two weeks to evaluate its stability to the backlight. In the VHR-14 measurement, the decaying voltage was measured over a period of 1000 milliseconds. Compositions with a large VHR-14 exhibit high stability to the backlight.

[0131] (14-1) Response time (τ(25); measured at 25°C; ms): An LCD5200 luminance meter manufactured by Otsuka Electronics Co., Ltd. was used for the measurement. The light source was a halogen lamp. The low-pass filter was set to 5 kHz. The sample was placed in an FFS element with a spacing (cell gap) of 3.2 μm between two glass substrates. A rectangular wave (60 Hz, 5 V, 0.5 s) was applied to the element. At this time, light was irradiated onto the element from the vertical direction, and the amount of light transmitted through the element was measured. When the amount of light reaches its maximum, the transmittance is considered to be 100%, and when the amount of light reaches its minimum, the transmittance is considered 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 as the sum of the rise time and fall time obtained in the manner described above.

[0132] (14-2) Response time (τ(-30); measured at -30°C; ms): Same as (14-1) except that the measurement was performed at -30°C and the application conditions of the rectangular wave were changed (60Hz, 5V, 15 seconds).

[0133] (15) Elastic constant (K; measured at 25°C; pN): An HP4284A LCR meter manufactured by Yokogawa Hewlett Packard Co., Ltd. was used for the measurement. A sample was placed in a horizontal alignment element with a spacing (cell gap) of 20 μm between two glass substrates. A charge of 0 to 20 volts was applied to the element, and the electrostatic capacitance and the applied voltage were measured. The measured electrostatic capacitance (C) and applied voltage (V) values ​​were fitted using equations (2.98) and (2.101) on page 75 of the "Liquid Crystal Device Handbook" (Nikkan Kogyo Shimbun), and the values ​​of K11 and K33 were obtained according to equation (2.99). Next, the values ​​of K11 and K33 obtained were used to calculate K22 using equation (3.18) on page 171 of the "Liquid Crystal Device Handbook". The elastic constant is represented by the average value of K11, K22 and K33 obtained in the manner described above.

[0134] (16) Specific resistance (ρ; measured at 25°C; Ωcm): 1.0 mL of the sample is injected into a container equipped with electrodes. A DC voltage (10V) is applied to the container, and the DC current is measured after 10 seconds. The specific resistance is calculated according to the following formula: (Specific resistance) = {(voltage) × (capacitance of the container)} / {(DC current) × (dielectric constant of vacuum)}.

[0135] (17) Pitch (P; measured at room temperature; μm): The pitch is measured using the wedge method (see page 196 of "LCD Handbook" (published in 2000, Maruzen)). The sample is injected into the wedge unit and left to stand at room temperature for 2 hours. The spacing (d2-d1) of the discclination lines is then observed using a polarizing microscope (Nikon, MM40 / 60 series). The pitch (P) is calculated using the following formula, which expresses the angle of the wedge unit as θ: P = 2 × (d2-d1) × tanθ.

[0136] (18) Dielectric constant in the short axis direction (ε⊥; measured at 25°C): The sample was placed in a TN element with a spacing (cell gap) of 9 μm between two glass substrates and a twist angle of 80 degrees. A sine wave (0.5V, 1kHz) 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.

[0137] (19) Frequency dependence of dielectric anisotropy (F10; measured at -20°C): A sample was placed in a TN element with a spacing (cell gap) of 9 μm between two glass substrates and a twist angle of 80 degrees. A sine wave (0.5V, 100Hz, 200Hz, 500Hz, 800Hz, 1kHz, 2kHz, 5kHz, 8kHz, 10kHz, 20kHz, 50kHz, 80kHz, 100kHz) was applied to the element, and the dielectric constant (ε⊥) of the liquid crystal molecules in the short axis direction was measured after 2 seconds. The frequency at which the dielectric anisotropy decreased by 10% relative to the dielectric anisotropy at 100Hz was defined as F10. The larger the F10, the smaller the frequency dependence.

[0138] [Synthesis example 1]

[0139] Synthesis of compound (1-7-1)

[0140] Step 1: Synthesis of compound (S-2)

[0141] Under nitrogen atmosphere, compound (S-1) (50 g) and tetrahydrofuran (THF) (1000 ml) were added to the reactor and cooled to -60°C. Lithium n-butyl (1.6 M; hexane and cyclohexane solution; 220 ml) was added dropwise, and the mixture was stirred for 2 hours. Then, sulfur powder (10.6 g) was added, and the mixture was stirred for 2 hours while restoring the temperature to 25°C. Bromoacetaldehyde diethyl acetal (65.4 g) was added, and the mixture was refluxed for 2 hours. The reaction mixture was injected into water and extracted with toluene. The organic layer was washed with water and dried with anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (toluene) to obtain compound (S-2) (84 g). Furthermore, compound (S-1) is sold and used by Combi-Blocks (Order Number: QJ-5097) and others.

[0142] Step 2: Synthesis of compound (S-3)

[0143] Under nitrogen atmosphere, compound (S-2) (75 g), polyphosphoric acid (100 g), and toluene (1000 ml) were added to a reactor and heated under reflux for 3 hours. The reaction mixture was then injected into water and extracted with toluene. The organic layer was washed with water and dried with anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (volume ratio, toluene:heptane = 2:3) to obtain compound (S-3) (42.0 g).

[0144] Step 3: Synthesis of compound (S-4)

[0145] Under nitrogen atmosphere, compound (S-3) (42 g) and THF (500 ml) were added to the reactor and cooled to -60°C. Lithium diisopropylamide (LDA) (1 M; hexane, THF solution; 196 ml) was added dropwise, and the mixture was stirred for 2 hours. Iodine (54.7 g) was then added, and the mixture was stirred for 2 hours while restoring the temperature to 25°C. The reaction mixture was injected into water and extracted with toluene. The organic layer was washed with water and dried with anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (volume ratio, toluene:heptane = 2:3) to obtain compound (S-4) (60.0 g). Furthermore, compound (S-5) was sold and used by Combi-Blocks (Order Number: FA-1772), etc.

[0146] Step 4: Synthesis of compound (1-7-1)

[0147] Under nitrogen atmosphere, compounds (S-4) (3g), (S-5) (2.8g), and toluene (80ml) were added to a reactor. Then, water (50ml), ethanol (50ml), Pd(PPh3)4 (0.3g), tetra-n-butyl ammonium bromide (TBAB) (0.28g), and potassium carbonate (2.4g) were added, and the mixture was heated to reflux for 6 hours. After the reaction, the mixture was extracted with toluene, washed with water, dried with anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain a light brown solid. This solid was prepared into a solution, subjected to silica gel column chromatography (heptane:toluene = 3:2 by volume ratio), and recrystallized (with ethanol) to obtain compound (1-7-1) (3.9g) as colorless crystals.

[0148] 1 H-NMR (δppm; CDCl3): 7.70(t,1H),7.64(d,1H),7.53(d,2H),7.44(d,1H),7.42(d,1H),7.3 1(d,1H),7.28(d,2H),4.27(q,2H),2.64(t,2H),1.69(sex,2H),1.44(t,3H),0.98(t,3H).

[0149] [Synthesis example 2]

[0150] Synthesis of compound (1-7-2)

[0151] Under nitrogen atmosphere, compounds (S-4) (3g), (S-6) (2.8g), and toluene (80ml) were added to a reactor, followed by water (50ml), ethanol (50ml), Pd(PPh3)4 (0.3g), TBAB (0.28g), and potassium carbonate (2.4g). The mixture was heated under reflux for 6 hours. After the reaction, the mixture was extracted with toluene, washed with water, dried with anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain a light brown solid. This solid was prepared into a solution, subjected to silica gel column chromatography (heptane:toluene = 3:2 by volume ratio), and recrystallized (with ethanol) to obtain compound (1-7-2) (4.0g) as colorless crystals. Furthermore, compound (S-6) was sold and used by Alfa Chemistry (Order Number: ACM163129144), etc.

[0152] 1 H-NMR (δppm; CDCl3): 7.70(t,1H),7.64(d,1H),7.53(d,2H),7.44(d,1H),7.42(d,1H),7.31(d,1H),7.28(d, 2H),4.27(q,2H),2.66(t,2H),1.64(quint,2H),1.44(t,3H),1.36(quint,2H),1.35(sex,2H),0.91(t,3H).

[0153] [Synthesis example 3]

[0154] Synthesis of compound (1-7-3)

[0155] Step 1: Synthesis of compound (S-8)

[0156] Under nitrogen atmosphere, compound (S-7) (5g) and THF (100ml) were added to the reactor and cooled to -60°C. Butyllithium (1.6M; hexane and cyclohexane solution; 24ml) was added dropwise, and the mixture was stirred for 2 hours. Then, sulfur powder (12g) was added, and the mixture was stirred for 2 hours while restoring the temperature to 25°C. Bromoacetaldehyde diethanolamide (7.4g) was added, and the mixture was refluxed for 2 hours. The reaction mixture was injected into water and extracted with toluene. The organic layer was washed with water and dried with anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (toluene) to obtain compound (S-8) (8.2g). Furthermore, compound (S-7) was sold and used by Combi-Blocks (Order Number: QC-7388), etc.

[0157] Step 2: Synthesis of compound (S-9)

[0158] Under nitrogen atmosphere, compound (S-8) (8.2 g), polyphosphoric acid (10 g), and toluene (100 ml) were added to a reactor and heated under reflux for 3 hours. The reaction mixture was then injected into water and extracted with toluene. The organic layer was washed with water and dried with anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (volume ratio, toluene:heptane = 2:3) to obtain compound (S-9) (4.2 g).

[0159] Step 3: Synthesis of compound (S-10)

[0160] Under nitrogen atmosphere, compound (S-9) (4.2 g) and THF (50 ml) were added to the reactor and cooled to -60°C. LDA (1 M; hexane, THF solution; 20 ml) was added dropwise, and the mixture was stirred for 2 hours. Iodine (5.7 g) was then added, and the mixture was stirred for 2 hours while restoring the temperature to 25°C. The reaction mixture was injected into water and extracted with toluene. The organic layer was washed with water and dried with anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (volume ratio, toluene:heptane = 2:3) to obtain compound (S-10) (6.1 g).

[0161] Step 4: Synthesis of compound (1-7-3)

[0162] Under nitrogen atmosphere, compounds (S-10) (6.1 g), (S-5) (6.0 g), and toluene (160 ml) were added to a reactor, followed by water (100 ml), ethanol (100 ml), Pd(PPh3)4 (0.5 g), TBAB (0.7 g), and potassium carbonate (5.0 g). The mixture was heated under reflux for 6 hours. After the reaction was complete, the mixture was extracted with toluene, washed with water, dried with anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain a light brown solid. The solid was then dissolved and subjected to silica gel column chromatography (heptane:toluene = 3:2 by volume) and recrystallization (ethanol) to obtain compound (1-7-3) (7.1 g) as colorless crystals.

[0163] 1 H-NMR (δppm; CDCl3): 7.72(t,1H),7.70(d,1H),7.54(d,2H),7.48(d,1H),7.4 4(d,1H),7.42(d,1H),7.29(d,2H),2.65(t,2H),1.70(sex,2H),0.99(t,3H).

[0164] [Synthesis Example 4]

[0165] Synthesis of compound (1-10-1)

[0166] Under nitrogen atmosphere, compound (S-4) (3g), compound (S-11) (2.8g), and toluene (80ml) were added to a reactor, followed by water (50ml), ethanol (50ml), Pd(PPh3)4 (0.3g), TBAB (0.28g), and potassium carbonate (2.4g). The mixture was heated under reflux for 6 hours. After the reaction, the mixture was extracted with toluene, washed with water, dried with anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain a light brown solid. This solid was prepared into a solution, subjected to silica gel column chromatography (heptane:toluene = 3:2 by volume ratio), and recrystallized (with ethanol) to obtain compound (1-10-1) (4.1g) as colorless crystals. Furthermore, compound (S-11) was purchased from A2B Chem (Order Number: AX54239) and used therein.

[0167] 1H-NMR (δppm; CDCl3): 7.54(d,1H),7.53(d,1H),7.28(d,1H),7.04(d,1H),7.02(d,1H) ,4.26(q,2H),2.49(t,1H),1.89(t,4H),1.50-1.18(m,10H),1.05(q,2H),0.91(t,3H).

[0168] [Synthesis Example 5]

[0169] Synthesis of compound (1-11-1)

[0170] Under nitrogen atmosphere, compounds (S-4) (3g), (S-12) (2.8g), and toluene (80ml) were added to a reactor, followed by water (50ml), ethanol (50ml), Pd(PPh3)4 (0.3g), TBAB (0.28g), and potassium carbonate (2.4g). The mixture was heated under reflux for 6 hours. After the reaction, the mixture was extracted with toluene, washed with water, dried with anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain a light brown solid. This solid was prepared into a solution, subjected to silica gel column chromatography (heptane:toluene = 3:2 by volume ratio), and recrystallized (with ethanol) to obtain compound (1-11-1) (4.0g) as colorless crystals. Furthermore, compound (S-12) was sold and used by Aquila Pharmatech (Order Number: AN11274).

[0171] 1 H-NMR (δppm; CDCl3): 7.58(d,1H),7.55(d,1H),7.28(d,1H),7.24(d,1H),7.19(d,1H),6.23(t,1H),4.27(q,2H),2. 42(br,2H),2.35(d,1H),1.94(d,1H),1.9-1.8(m,1H),1.61(sex,1H),1.42(t,3H),1.41-1.25(m,5H),0.93(t,3H).

[0172] The comparative compound (C-1) was synthesized as a compound similar to the compound (1-7-1) of the present invention, following the same procedure as described in Example 8 of International Publication No. 2016 / 132998.

[0173] 1H-NMR (δppm; CDCl3): 7.70(t,1H),7.67(dd,1H),7.54(d,2H),7.48(d,1H),7.43(dd,1H),7.41(dd, 1H),7.27(d,2H),7.09(t,1H),4.21(q,2H),2.64(t,2H),1.69(sex,2H),1.47(t,3H),0.98(t,3H).

[0174] Examples of the compositions are shown below. The component compounds are represented by codes based on the definitions in Table 3 below. In Table 3, the stereoconfiguration associated with 1,4-cyclohexylene is the trans configuration. The number in parentheses following the coded compound indicates the chemical formula to which the compound belongs. The code (-) refers to other liquid crystal compounds. The proportion (percentage) of the liquid crystal compounds is a mass percentage (mass %) based on the mass of the liquid crystal composition excluding additives. Finally, the characteristic values ​​of the compositions are summarized.

[0175] Table 3. Representation of compounds using codes R-(A1)-Z1-·····-Z n -(A n )-R′

[0176] [Example 1]

[0177] NI = 79.8℃; T C <-20℃; Δn=0.122; Δε=4.0; γ1=52.2mPa·s; K=11.7pN; τ(25)=17.8ms

[0178] Compositions that do not contain compound (1) and are equivalent to NI were prepared based on the composition of Example 1.

[0179] [Comparative Example 1]

[0180] NI = 78.9℃; T C <-20℃; Δn=0.122; Δε=3.9; γ1=53.7mPa·s; K=11.2pN; τ(25)=18.7ms

[0181] Based on the composition of Example 1, a composition equivalent to NI was prepared by replacing compound (1) with compound (C-1).

[0182] [Comparative Example 2]

[0183] NI = 78.4℃; T C<-10℃;Δn=0.122;Δε=3.8;γ1=52.0mPa·s;K=11.2pN;τ(25)=18.4ms

[0184] [example2]

[0185] NI=79.1℃;T C <-20℃;Δn=0.122;Δε=3.9;γ1=50.4mPa·s;K=11.6pN;τ(25)=17.4ms

[0186] [example3]

[0187] NI=79.5℃;T C <-20℃;Δn=0.122;Δε=4.0;γ1=52.8mPa·s;K=11.8pN;τ(25)=18.0ms

[0188] [example4]

[0189] NI=75.7℃;T C <-15℃;Δn=0.149;Δε=3.0;γ1=39.3mPa·s;K=12.7pN;τ(25)=15.9ms

[0190] [example5]

[0191] NI=105.2℃;T C <-40℃;Δn=0.125;Δε=3.9;γ1=74.8mPa·s;K=16.7pN;τ(25)=24.6ms

[0192] [example 6]

[0193] NI=78.9℃;Tc<-15℃;Δn=0.140;Δε=2.8;γ1=41.4mPa·s;K=11.3pN;τ(25)=11.9ms

[0194] [example7]

[0195] NI=95.3℃;Tc<-25℃;Δn=0.112;Δε=2.2;γ1=52.8mPa·s;K=11.7pN;τ(25)=20.6ms

[0196] [example8]

[0197] NI=80.0℃; Tc<-20℃; Δn=0.133; Δε=2.9; γ1=44.9mPa·s; K=12.0pN; τ(25)=15.4ms

[0198] [Example 9]

[0199] NI=80.4℃; Tc<-15℃; Δn=0.110; Δε=3.9; γ1=44.3mPa·s; K=12.1pN; τ(25)=16.6ms

[0200] [Example 10]

[0201] NI=79.9℃; Tc<-20℃; Δn=0.121; Δε=3.8; γ1=43.0mPa·s; K=12.2pN; τ(25)=16.0ms

[0202] The elastic constant K and response time τ(25) of the composition of Example 1 were 11.7 pN and 17.8 ms, respectively, and the nematic phase was maintained at -20°C with respect to the lower limit temperature. On the other hand, the elastic constant K and response time τ(25) of the composition of Comparative Example 1 were 11.2 pN and 18.7 ms, respectively, and the elastic constant K and response time τ(25) of the composition of Comparative Example 2 were 11.2 pN and 18.4 ms, respectively, and the nematic phase could not be maintained at -20°C with respect to the lower limit temperature. Therefore, it is concluded that the liquid crystal composition of the present invention has excellent properties. Industrial applicability

[0203] The liquid crystal composition of the present invention can be used in liquid crystal monitors, liquid crystal televisions, etc.

Claims

A liquid crystal composition containing, as a component A, at least one compound selected from the group consisting of compounds represented by formula (1) and having a positive dielectric anisotropy; In equation (1), R 1 and R 2 It is an alkyl group having 1 to 12 carbon atoms, wherein at least one -CH2- can be substituted with -O- or -S-, and at least one -(CH2)2- can be substituted with -CH=CH-, wherein at least one hydrogen atom can be substituted with a halogen; ring A 1 It is 1,4-cyclohexene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which at least one hydrogen atom is substituted by fluorine or chlorine; Z 1 For single bonds, -(CH2)2-, -CH=CH-, -CF=CF-, -C≡C-, -COO-, -OCO-, -CF2O-, -OCF2-, -CH2O-, -OCH2-, -(CH2)4-, -(CH2)2CF2O-, -(CH2)2OCF2-, -CF2O(CH2)2-, -OCF2(CH2)2-, -CH=CH-(CH2)2- or -(CH2)2-CH=CH-; a is 1, 2 or 3. The liquid crystal composition according to claim 1, which contains at least one compound selected from the group consisting of compounds represented by formulae (1-1) to (1-11) as component A. In equations (1-1) to (1-11), R 1 It is an alkoxy group having 1 to 12 carbon atoms, an alkenyloxy group having 2 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine; R 2 It is 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 composition according to claim 1 or 2, wherein The proportion of component A ranges from 1% to 30% by mass. The liquid crystal composition according to claim 1, which contains at least one compound selected from the group consisting of compounds represented by formula (2) and formula (3) as component B; In equation (2), R 3 It 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 B is 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; Z 2 It is a single bond, ethylidene, vinylidene, carbonyloxy, or difluoromethyleneoxy; X 1 and X 2 It is hydrogen or fluorine; Y 1 It is fluorine, chlorine, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine, or an alkenyloxy group having 2 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine; b is 1, 2, 3 or 4. In equation (3), R 4 It 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; the ring C is 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, or 1,3-dioxane-2,5-diyl; Z 3 It is a single bond, carbonyloxy group, or difluoromethyleneoxy group; X 3 and X 4 It is hydrogen or fluorine; c is 1, 2, 3 or 4. The liquid crystal composition as claimed in claim 1 or 4, which contains at least one compound selected from the group consisting of the compounds represented by formulae (2-1) to (2-37) and formulae (3-1) to (3-8) as component B; In formulae (2-1) to (2-37), R 3 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 formula (3-1) to formula (3-8), R 4 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; X 3 and X 4 are hydrogen or fluorine. The liquid crystal composition according to claim 4, wherein The proportion of component B ranges from 5% to 50% by mass. The liquid crystal composition as claimed in claim 1 or 4, which contains at least one compound selected from the group consisting of compounds represented by formula (4) as component C. In equation (4), R 5 and R 6 It is 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 in which at least one hydrogen atom is substituted by fluorine or chlorine; ring D and ring E are 1,4-cyclohexene, 1,4-cyclohexenyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene; Z 4 It is a single bond, ethylidene, vinylidene, methyleneoxy, or carbonyloxy; d is 1, 2, or 3. The liquid crystal composition according to claim 1, which contains at least one compound selected from the group consisting of compounds represented by formulae (4-1) to (4-16) as component C. In equations (4-1) to (4-16), R 5 and R 6 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is replaced by fluorine or chlorine, or an alkenyl group having 2 to 12 carbon atoms in which at least one hydrogen atom is replaced by fluorine or chlorine. The liquid crystal composition according to claim 7, wherein The proportion of component C ranges from 10% to 85% by mass. The liquid crystal composition as claimed in claim 1, which contains at least one compound selected from the compounds represented by formula (5) as component D. In equation (5), R 7 and R 8 The alkyl group is 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, an alkenyloxy group having 2 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is substituted by fluorine or chlorine; cyclic F and cyclic I are 1,4-cyclohexene, 1,4-cyclohexenyl, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene in which at least one hydrogen atom is substituted by fluorine or chlorine, naphth-2,6-diyl, naphth-2,6-diyl in which at least one hydrogen atom is substituted by fluorine or chlorine, chromoline-2,6-diyl, or an alkyl group having at least one hydrogen atom substituted by fluorine or chlorine. Chlorinated chromoproto-2,6-diyl; ring G is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 1,8-difluorophenanthrene-2,7-diyl, 3,4,5-trifluoronaphthio-2,6-diyl, 7,8-difluorochromoproto-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 5 and Z 6 It is a single bond, ethylidene, vinylidene, methyleneoxy, or carbonyloxy; e is 0, 1, 2, or 3, f is 0 or 1; and the sum of e and f is less than 3. The liquid crystal composition according to claim 10, which contains at least one compound selected from the group consisting of compounds represented by formulae (5-1) to (5-36) as component D. In equations (5-1) to (5-36), R 7 and R 8 It is 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, an alkenyloxy group having 2 to 12 carbon atoms, or an alkyl group having 1 to 12 carbon atoms in which at least one hydrogen atom is replaced by fluorine or chlorine. The liquid crystal composition according to claim 10, wherein The proportion of component D ranges from 1% to 20% by mass. A liquid crystal display element comprising the liquid crystal composition as described in claim 1. The liquid crystal display element according to Claim 13, wherein The operating modes are torsional nematic mode, electrically controlled birefringence mode, optically compensated bending mode, in-plane switching mode, edge field switching mode, or electric field-induced photoresponse alignment mode, and the driving method is active matrix mode. Use of a liquid crystal composition, the liquid crystal composition as described in claim 1, in a liquid crystal display element.

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