Liquid crystal composition and liquid crystal display element

Abstract

To provide a liquid crystal composition which satisfies at least one characteristic such as: a high upper limit temperature; a low lower limit temperature; a low viscosity, especially a low viscosity at low temperature; a suitable optical anisotropy; a large dielectric anisotropy; a large dielectric constant in short axis direction; a large ratio of the dielectric constant in short axis direction to the dielectric anisotropy; low frequency dependence of the dielectric anisotropy at low temperature; a large specific resistance; high stability to light and heat; and a large elastic constant, or has a suitable balance with regard to at least two of the characteristics, and to provide an AM element including the composition.SOLUTION: A liquid crystal composition comprises: a specific compound having a high upper limit temperature as a component A; a specific compound having a large dielectric anisotropy as a component B; and a specific compound having a large dielectric constant in short axis direction as a component C, and may contain: a specific compound having a low viscosity or a high upper limit temperature as a component D; or a specific compound having a large dielectric constant in short axis direction as a component E.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to liquid crystal compositions, liquid crystal display elements containing the composition, and the like. In particular, it relates to liquid crystal compositions with positive dielectric anisotropy, and AM (active matrix) elements containing the composition and having modes TN, ECB, OCB, IPS, FFS, or FPA. [Background technology]

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

[0003] Liquid crystal display elements contain a liquid crystal composition having a nematic phase. This composition has appropriate properties. By improving the properties of this composition, AM elements with good properties can be obtained. The relationships between these properties are 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 temperature limit of the nematic phase is about 70°C or higher, and the preferred lower temperature limit of the nematic phase is about -10°C or lower. The viscosity of the composition is related to the response time of the element. A short response time is preferred for displaying motion pictures with the element. A response time even shorter than 1 millisecond is desirable. Therefore, a low viscosity in the composition is preferred. A low viscosity at low temperatures is even more preferred. The elastic constant of the composition is related to the contrast of the element. To increase the contrast in the element, a large elastic constant in the composition is preferred.

[0004] TIFF0007894217000001.tif67153

[0005] The optical anisotropy of a composition is related to the contrast ratio of the element. Depending on the mode of the element, either large or small optical anisotropy, i.e., appropriate optical anisotropy, is required. The product of the optical anisotropy of the composition (Δn) and the cell gap of the element (d) (Δn × d) is designed to maximize the contrast ratio. The appropriate value of the product depends on the type of operating mode. For elements of modes such as TN, the appropriate value is approximately 0.45 μm. In this case, a composition with large optical anisotropy is preferred for elements with a small cell gap. Large dielectric anisotropy in a composition contributes to a low threshold voltage, low power consumption, and a large contrast ratio in the element. Therefore, large dielectric anisotropy is preferred. Dielectric anisotropy is generally frequency-dependent at low temperatures and decreases with increasing frequency. For this reason, at low temperatures, as the driving frequency increases, the motion of liquid crystal molecules cannot keep up with the frequency change of the voltage, resulting in display defects. Therefore, it is preferable for the frequency dependence of dielectric anisotropy at low temperatures to be small. A high resistivity in a composition contributes to a high voltage retention rate and a high contrast ratio in the element. Therefore, a composition with high resistivity in the initial stage is preferred. A composition with high resistivity 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. When these stabilities are high, the lifespan of the element is long. Such characteristics are preferred for AM elements used in liquid crystal monitors, liquid crystal televisions, and the like.

[0006] AM elements having a TN mode use compositions with positive dielectric anisotropy. AM elements having a VA mode use compositions with negative dielectric anisotropy. Polymer-sustained alignment (PSA) type AM elements use compositions with positive or negative dielectric anisotropy.

[0007] AM elements in IPS mode or FFS mode use compositions with positive or negative dielectric anisotropy. Generally, it is known that the transmittance is lower when using a composition with positive dielectric anisotropy compared to when using a composition with negative dielectric anisotropy. To improve this, it has been proposed to include a compound with negative dielectric anisotropy in the composition with positive dielectric anisotropy (for example, Patent Document 1).

[0008] It is believed that incorporating a compound with negative dielectric anisotropy increases the dielectric constant (ε⊥) in the short axis direction of the composition, or the ratio of the dielectric constant in the short axis direction to the dielectric anisotropy (ε⊥ / Δε), thereby improving transmittance. On the other hand, a problem arises when a compound with negative dielectric anisotropy is included, as it can lead to a decrease in response.

[0009] Liquid crystal display elements now have a variety of applications, and depending on the application, it is required that good display performance be maintained even under harsh temperature conditions. To achieve this, it is necessary for them to operate appropriately over a wide temperature range and to have excellent response under harsh temperature conditions. Liquid crystal display elements are known to have a decrease in response, especially at low temperatures, and research is being conducted to improve this (for example, Patent Document 2). Patent Document 3 also discloses that a liquid crystal composition containing a tercyclohexyl compound has a nematic phase over a wide temperature range. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2013-166936 [Patent Document 2] Japanese Patent Publication No. 2002-294238 [Patent Document 3] German Patent Application Publication No. 4414647 [Overview of the project] [Problems that the invention aims to solve]

[0011] The object of the present invention is to provide a liquid crystal composition that satisfies at least one of the following characteristics: a high upper limit temperature of the nematic phase, a low lower limit temperature of the nematic phase, low viscosity, especially low viscosity at low temperatures, appropriate optical anisotropy, large dielectric anisotropy, large dielectric constant in the short axis direction (ε⊥), large ratio of dielectric constant in the short axis direction to dielectric anisotropy (ε⊥ / Δε), small frequency dependence of dielectric anisotropy at low temperatures, large resistivity, high stability against light, high stability against heat, and large elastic constants; and a liquid crystal display element that satisfies at least one of the following characteristics: a short response time, especially a short response time at low temperatures, and a low threshold voltage, especially a low threshold voltage at low temperatures. Another challenge is to provide a liquid crystal composition having a suitable balance between at least two of the following properties: a high upper temperature limit for the nematic phase, a low lower temperature limit for the nematic phase, low viscosity, especially low viscosity at low temperatures, appropriate optical anisotropy, large dielectric anisotropy, large dielectric constant in the short axis direction, a large ratio of dielectric constant in the short axis direction to dielectric anisotropy (ε⊥ / Δε), small frequency dependence of dielectric anisotropy at low temperatures, large resistivity, high stability to light, high stability to heat, and large elastic constants. Another challenge is to provide an AM element having properties such as a large voltage retention rate, a large contrast ratio, and a long lifetime. [Means for solving the problem]

[0012] The present invention relates to a liquid crystal composition having positive dielectric anisotropy, comprising at least one compound selected from compounds represented by formula (1) as component A, at least one compound selected from compounds represented by formula (2) as component B, and at least one compound selected from compounds represented by formula (3) as component C, and a liquid crystal display element containing this composition. TIFF0007894217000002.tif56107 In equation (1), R 1 R is an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms; 2is an alkenyl having 2 to 12 carbon atoms; Z 1 is a single bond or vinylene; In formula (2), R 3 is an alkyl having 1 to 12 carbon atoms, an alkoxy having 1 to 12 carbon atoms, or an alkenyl having 2 to 12 carbon atoms; ring A is 1,4 - cyclohexylene, 1,4 - phenylene, 2 - fluoro - 1,4 - phenylene, 2,3 - difluoro - 1,4 - phenylene, 2,6 - difluoro - 1,4 - phenylene, pyrimidine - 2,5 - diyl, 1,3 - dioxane - 2,5 - diyl, or tetrahydropyran - 2,5 - diyl; Z 2 is a single bond, ethylene, vinylene, carbonyloxy, or difluoromethyleneoxy; X 1 and X 2 are hydrogen or fluorine; Y 1 is fluorine, chlorine, an alkyl having 1 to 12 carbon atoms in which at least one hydrogen is replaced by fluorine or chlorine, an alkoxy having 1 to 12 carbon atoms in which at least one hydrogen is replaced by fluorine or chlorine, or an alkenyloxy having 2 to 12 carbon atoms in which at least one hydrogen is replaced by fluorine or chlorine; a is 1, 2, 3, or 4; In formula (3), R 4 and R 5is hydrogen, C1 to C12 alkyl, C1 to C12 alkoxy, C2 to C12 alkenyl, or C2 to C12 alkenyloxy; ring B and ring D are 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene with at least one hydrogen replaced by fluorine or chlorine, naphthalene-2,6-diyl, naphthalene-2,6-diyl with at least one hydrogen replaced by fluorine or chlorine, chroman-2, 6-diyl, or chroman-2,6-diyl in which at least one hydrogen is replaced by fluorine or chlorine; ring C is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diyl, 7,8-difluorochroman-2,6-diyl, 3,4,5,6-tetrafluorofluorene-2,7-diyl, or 1,1,6,7-tetrafluoroindan-2,5-diyl; Z 3 and Z 4 b is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy; b is 1, 2, or 3, c is 0 or 1; and the sum of b and c is 2 or 3. [Effects of the Invention]

[0013] The advantages of the present invention are to provide a liquid crystal composition that satisfies at least one of the following characteristics: a high upper limit temperature of the nematic phase, a low lower limit temperature of the nematic phase, low viscosity, especially low viscosity at low temperatures, appropriate optical anisotropy, large dielectric anisotropy, large dielectric constant in the short axis direction (ε⊥), large ratio of dielectric constant in the short axis direction to dielectric anisotropy (ε⊥ / Δε), small frequency dependence of dielectric anisotropy at low temperatures, large resistivity, high stability against light, high stability against heat, and large elastic constants; and a liquid crystal display element that satisfies at least one of the following characteristics: a short response time, especially short response time at low temperatures, and a low threshold voltage, especially low threshold voltage at low temperatures. Another advantage is to provide a liquid crystal composition having a good balance between at least two of the following properties: a high upper temperature limit for the nematic phase, a low lower temperature limit for the nematic phase, low viscosity, especially low viscosity at low temperatures, appropriate optical anisotropy, large dielectric anisotropy, large dielectric constant in the short axis direction, a large ratio of dielectric constant in the short axis direction to dielectric anisotropy (ε⊥ / Δε), small frequency dependence of dielectric anisotropy at low temperatures, large resistivity, high stability to light, high stability to heat, and large elastic constants. Another advantage is to provide an AM element having properties such as a large voltage retention rate, a large contrast ratio, and a long lifetime. [Brief explanation of the drawing]

[0014] [Figure 1] This graph shows the frequency dependence of the dielectric anisotropy at -20°C for the liquid crystal compositions of Comparative Example 1, Example 1, and Example 2. [Modes for carrying out the invention]

[0015] The following terms are used in this specification: The terms "liquid crystal composition" and "liquid crystal display element" may be 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 phase or a smectic phase, and compounds that do not have a liquid crystal phase but are mixed into a composition for the purpose of adjusting properties such as the temperature range, viscosity, and dielectric anisotropy of the nematic phase. These compounds have a six-membered ring, such as 1,4-cyclohexylene and 1,4-phenylene, and their molecules (liquid crystal molecules) are rod-like. "Polymerizable compound" is a compound added to a composition for the purpose of generating a polymer. Liquid crystal compounds having alkenils are not classified as polymerizable compounds in this sense. The term "low temperature" means a temperature of approximately -20°C or lower.

[0016] Liquid crystal compositions are prepared by mixing multiple liquid crystalline compounds. Additives such as optically active compounds and polymerizable compounds are added to these liquid crystal compositions as needed. The proportion of liquid crystalline compounds is expressed as a mass percentage (mass%) based on the mass of the liquid crystal composition without additives, even when additives are added. The proportion of additives is also expressed as a mass percentage (mass%) based on the mass of the liquid crystal composition without additives. In other words, the proportions of liquid crystalline compounds and additives are calculated based on the total mass of the liquid crystalline compounds. The proportions of polymerization initiators and polymerization inhibitors are exceptionally expressed based on the mass of the polymerizable compounds.

[0017] "Upper temperature limit of the nematic phase" is sometimes abbreviated as "upper temperature." "Lower temperature limit of the nematic phase" is sometimes abbreviated as "lower temperature." The expression "increase dielectric anisotropy" means that for compositions with positive dielectric anisotropy, the value increases positively, and for compositions with negative dielectric anisotropy, the value increases negatively. "Large voltage retention rate" means that the element has a large voltage retention rate not only at room temperature but also at temperatures close to the upper temperature limit in the initial stage, and that it maintains a large voltage retention rate not only at room temperature but also at temperatures close to the upper temperature limit after prolonged use. The characteristics of compositions and elements may be examined through time-dependent tests.

[0018] TIFF0007894217000003.tif2071 Let's explain using the compound (1z) above as an example. In formula (1z), the symbols α and β enclosed in hexagons correspond to rings α and β, respectively, representing rings such as a six-membered ring and a fused ring. When the subscript 'x' is 2, there are two rings α. The two groups represented by the two rings α may be the same or different. This rule applies to any two rings α when the subscript 'x' is greater than 2. This rule also applies to other symbols, such as the bonding group Z. A diagonal line across one side of ring β indicates that any hydrogen on ring β may be replaced by a substituent (-Sp-P). The subscript 'y' indicates the number of substitutions. When the subscript 'y' is 0, there are no such substitutions. When the subscript 'y' is 2 or greater, there are multiple substituents (-Sp-P) on ring β. In this case as well, the rule "may be the same or different" applies. Note that this rule also applies when the symbol Ra is used for multiple compounds.

[0019] In formula (1z), for example, the expression "Ra and Rb are alkyl, alkoxy, or alkenyl" means that Ra and Rb are independently selected from the group alkyl, alkoxy, and alkenyl. Here, the group represented by Ra and the group represented by Rb may be the same or different.

[0020] At least one compound selected from the compounds represented by formula (1z) is sometimes abbreviated as "compound (1z)". "Compound (1z)" means one compound represented by formula (1z), a mixture of two compounds, or a mixture of three or more compounds. The same applies to compounds represented by other formulas. The expression "at least one compound selected from the compounds represented by formula (1z) and formula (2z)" means at least one compound selected from the group of compounds (1z) and compounds (2z).

[0021] The expression "at least one 'A'" means that the number of 'A's is arbitrary. The expression "at least one 'A' may be replaced by a 'B'" means that when there is one 'A', its position is arbitrary, and when there are two or more 'A's, their positions can be chosen without restriction. The expression "at least one -CH2- may be replaced by -O-" is sometimes used. In this case, -CH2-CH2-CH2- may be converted to -O-CH2-O- by replacing a non-adjacent -CH2- with -O-. However, adjacent -CH2- will not be replaced by -O-, because this replacement would produce -OO-CH2- (peroxide).

[0022] The alkyl groups in liquid crystalline compounds are linear or branched and do not include cyclic alkyl groups. Linear alkyl groups are preferred over branched alkyl groups. These also apply to terminal groups such as alkoxy and alkenyl groups. For 1,4-cyclohexylene, the trans configuration is preferred over the cis configuration to increase the upper temperature limit. Since 2-fluoro-1,4-phenylene is asymmetric, both left-facing (L) and right-facing (R) configurations exist. TIFF0007894217000004.tif25112 The same applies to divalent groups such as tetrahydropyran-2,5-diyl. The same also applies to binding groups (-COO- or -OCO-) such as carbonyloxy.

[0023] The present invention includes the following items, among others.

[0024] Item 1. A liquid crystal composition having positive dielectric anisotropy, comprising at least one compound selected from compounds represented by formula (1) as component A, at least one compound selected from compounds represented by formula (2) as component B, and at least one compound selected from compounds represented by formula (3) as component C. TIFF0007894217000005.tif56107 In equation (1), R 1 R is an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms; 2 These are alkenyls with 2 to 12 carbon atoms; Z 1 is a single bond or vinylene; In equation (2), R 3 Ring A is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; Ring A is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; Z 2 X is a single bond, ethylene, vinylene, carbonyloxy, or difluoromethyleneoxy; 1 and X 2 is hydrogen or fluorine; Y 1 a is fluorine, chlorine, a C1 to C12 alkyl group in which at least one hydrogen is replaced by fluorine or chlorine, a C1 to C12 alkoxy group in which at least one hydrogen is replaced by fluorine or chlorine, or a C2 to C12 alkenyloxy group in which at least one hydrogen is replaced by fluorine or chlorine; a is 1, 2, 3, or 4; In equation (3), R 4 and R 5is hydrogen, C1 to C12 alkyl, C1 to C12 alkoxy, C2 to C12 alkenyl, or C2 to C12 alkenyloxy; ring B and ring D are 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene with at least one hydrogen replaced by fluorine or chlorine, naphthalene-2,6-diyl, naphthalene-2,6-diyl with at least one hydrogen replaced by fluorine or chlorine, chroman-2, 6-diyl, or chroman-2,6-diyl in which at least one hydrogen is replaced by fluorine or chlorine; ring C is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diyl, 7,8-difluorochroman-2,6-diyl, 3,4,5,6-tetrafluorofluorene-2,7-diyl, or 1,1,6,7-tetrafluoroindan-2,5-diyl; Z 3 and Z 4 b is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy; b is 1, 2, or 3, c is 0 or 1; and the sum of b and c is 2 or 3.

[0025] Item 2. The liquid crystal composition according to Item 1, comprising as component A, at least one compound selected from the compounds represented by formulas (1-1) and (1-2). TIFF0007894217000006.tif3091 In equations (1-1) and (1-2), R 1 These are alkyl groups having 1 to 12 carbon atoms or alkenyl groups having 2 to 12 carbon atoms.

[0026] Item 3. The liquid crystal composition according to item 1 or 2, wherein the proportion of component A is in the range of 1% by mass to 20% by mass.

[0027] Item 4. A liquid crystal composition according to any one of items 1 to 3, comprising, as component B, at least one compound selected from the compounds represented by formulas (2-1) to (2-36). TIFF0007894217000007.tif222122 TIFF0007894217000008.tif224121 TIFF0007894217000009.tif233128 TIFF0007894217000010.tif240125 In equations (2-1) to (2-36), R 3 These are alkyl groups having 1 to 12 carbon atoms, alkoxy groups having 1 to 12 carbon atoms, or alkenyl groups having 2 to 12 carbon atoms.

[0028] Item 5. A liquid crystal composition according to any one of items 1 to 4, wherein the proportion of component B is in the range of 10% by mass to 85% by mass.

[0029] Item 6. A liquid crystal composition according to any one of items 1 to 5, comprising as component C, at least one compound selected from the compounds represented by formulas (3-1) to (3-20). TIFF0007894217000011.tif219132 TIFF0007894217000012.tif224130 In equations (3-1) to (3-20), R 4 and R 5 These are hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyloxy group having 2 to 12 carbon atoms.

[0030] Item 7. A liquid crystal composition according to any one of items 1 to 6, wherein the proportion of component C is in the range of 10% by mass to 50% by mass.

[0031] Item 8. A liquid crystal composition according to any one of items 1 to 7, comprising at least one compound selected from the compounds represented by formula (4) as component D. TIFF0007894217000013.tif20107 In equation (4), R 6 and R 7 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 replaced by fluorine or chlorine; rings E and F are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene; Z 5 is a single bond, ethylene, methyleneoxy, or carbonyloxy; d is 1, 2, or 3; however, d is 2 and there are two Z 5 When the bond is a single bond, ring F is 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene.

[0032] Item 9. A liquid crystal composition according to any one of items 1 to 8, comprising as component D, at least one compound selected from the compounds represented by formulas (4-1) to (4-13). TIFF0007894217000014.tif103102 TIFF0007894217000015.tif114109 In equations (4-1) to (4-13), R 6 and R 7 These are C1 to C12 alkyl groups, C1 to C12 alkoxy groups, C2 to C12 alkenyl groups, or C2 to C12 alkenyl groups in which at least one hydrogen atom is replaced by fluorine or chlorine.

[0033] Item 10. The liquid crystal composition according to item 8 or 9, wherein the proportion of component D is in the range of 10% by mass to 75% by mass.

[0034] Item 11. A liquid crystal composition according to any one of items 1 to 10, comprising at least one compound selected from the compounds represented by formula (5) as component E. TIFF0007894217000016.tif21109 In equation (5), R 8 and R 9 Ring G is hydrogen, a C1-C12 alkyl, a C1-C12 alkoxy, a C2-C12 alkenyl, or a C2-C12 alkenyloxy; ring G is 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene with at least one hydrogen replaced by fluorine or chlorine, naphthalene-2,6-diyl, naphthalene-2,6-diyl with at least one hydrogen replaced by fluorine or chlorine, chroman-2,6-diyl, or with at least one hydrogen replaced by fluorine or chlorine The substituted chroman-2,6-diyl; ring I is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diyl, 7,8-difluorochroman-2,6-diyl, 3,4,5,6-tetrafluorofluorene-2,7-diyl, 4,6-difluorodibenzofuran-3,7-diyl, 4,6-difluorodibenzothiophene-3,7-diyl, or 1,1,6,7-tetrafluoroindan-2,5-diyl;;Z 6 is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy; e is 0 or 1.

[0035] Item 12. A liquid crystal composition according to any one of items 1 to 11, comprising, as component E, at least one compound selected from the compounds represented by formulas (5-1) to (5-15). TIFF0007894217000017.tif152134 TIFF0007894217000018.tif177131 In equations (5-1) to (5-15), R 8 and R 9 These are hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyloxy group having 2 to 12 carbon atoms.

[0036] Item 13. The liquid crystal composition according to item 11 or 12, wherein the proportion of component E is in the range of 1% by mass to 30% by mass.

[0037] Item 14. A liquid crystal composition according to any one of items 1 to 13, wherein the upper limit temperature of the nematic phase is 70°C or higher, the optical anisotropy at a wavelength of 589 nm (measured at 25°C) is 0.07 or higher, and the dielectric anisotropy at a frequency of 1 kHz (measured at 25°C) is 2.0 or higher.

[0038] Item 15. A liquid crystal composition according to any one of items 1 to 14, for use in liquid crystal display elements with an operating mode of IPS mode or FFS mode.

[0039] Item 16. A liquid crystal display element containing the liquid crystal composition described in any one of items 1 to 14.

[0040] Item 17. A liquid crystal display element according to Item 16, wherein the operating mode of the liquid crystal display element is TN mode, ECB mode, OCB mode, IPS mode, FFS mode, or FPA mode, and the driving method of the liquid crystal display element is an active matrix method.

[0041] Item 18. Use of a liquid crystal composition described in any one of items 1 to 14 in a liquid crystal display element.

[0042] The present invention also includes the following: (a) The above composition containing one, two, or three or more compounds selected from additives such as optically active compounds, antioxidants, ultraviolet absorbers, quenchers, dyes, defoamers, polymerizable compounds, polymerization initiators, polymerization inhibitors, and polar compounds. (b) AM elements containing the above composition. (c) The above composition further containing a polymerizable compound, and a polymer-supported orientation (PSA) type AM element containing this composition. (d) A polymer-supported orientation (PSA) type AM element containing the above composition, wherein the polymerizable compound in the composition is polymerized. (e) An element containing the above composition and having modes of PC, TN, STN, ECB, OCB, IPS, VA, FFS, or FPA. (f) A transmission element containing the above composition. (g) Use of the above composition as a composition having a nematic phase. (h) Use of an optically active composition obtained by adding an optically active compound to the above composition.

[0043] The composition of the present invention will be described in the following order. First, the composition will be described. Second, the main properties of the component compounds and the main effects that these compounds have on the composition and the device will be described. Third, the combination of component compounds in the composition, preferred proportions, and the rationale therefor will be described. Fourth, preferred forms of the component compounds will be described. Fifth, preferred component compounds will be shown. Sixth, additives that may be added to the composition will be described. Seventh, the synthesis method of the component compounds will be described. Finally, the uses of the composition will be described.

[0044] First, the composition will be described. This composition contains multiple liquid crystalline compounds. This composition may also contain additives. Additives include optically active compounds, antioxidants, ultraviolet absorbers, quenchers, dyes, defoamers, polymerizable compounds, polymerization initiators, polymerization inhibitors, polar compounds, etc. This composition is classified into composition A and composition B from the viewpoint of liquid crystalline compounds. Composition A may further contain other liquid crystalline compounds, additives, etc., in addition to liquid crystalline compounds selected from compounds (1), (2), (3), (4), and (5). "Other liquid crystalline compounds" are liquid crystalline compounds different from compounds (1), (2), (3), (4), and (5). Such compounds are mixed into the composition for the purpose of further adjusting the properties.

[0045] Composition B consists substantially of only liquid crystalline compounds selected from compound (1), compound (2), compound (3), compound (4), and compound (5). "Substantially" means that composition B may contain additives, but does not contain other liquid crystalline compounds. Composition B has fewer components than composition A. From the viewpoint of reducing costs, composition B is preferred over composition A. From the viewpoint that properties can be further adjusted by mixing in other liquid crystalline compounds, composition A is preferred over composition B.

[0046] To prepare a liquid crystal composition having a suitable balance between at least two properties such as a high upper temperature limit for the nematic phase, a low lower temperature limit for the nematic phase, low viscosity, appropriate optical anisotropy, high dielectric anisotropy, high resistivity, high stability to light, high stability to heat, and a large elastic constant, it is preferable not to include the compound represented by formula (S) and the compound represented by formula (T). TIFF0007894217000019.tif21107 TIFF0007894217000020.tif22106 In equation (S), R S1 and R S2is a fluorinated alkyl, fluorinated alkenyl, fluorinated alkoxy, fluorine, chlorine, or cyano; ring A S is 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene, 1,4-phenylene in which at least one hydrogen is replaced by fluorine, 1,3-dioxan-2,5-diyl, or tetrahydropyran-2,5-diyl; ring B S These are 2,3-difluoro-1,4-phenylene, 4,6-difluorodibenzofuran-3,7-diyl, or 4,6-difluorodibenzothiophen-3,7-diyl; Z S is a single bond, ethylene, vinylene, methyleneoxy, carbonyloxy, or difluoromethyleneoxy; s is 0, 1, 2, or 3; In equation (T), R T1 and R T2 is alkyl, alkenyl, alkoxy, alkenyloxy, fluorinated alkyl, fluorinated alkenyl, fluorinated alkoxy, fluorine, chlorine, or cyano; ring A T t is 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene, 1,4-phenylene in which at least one hydrogen is replaced by fluorine, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; t is 1 or 2.

[0047] Secondly, the main properties of the component compounds and their main effects on the composition and device are described. The main properties of the component compounds are summarized in Table 2. In the symbols in Table 2, L means large or high, M means medium, and S means small or low. The symbols L, M, and S are classifications based on qualitative comparisons between the component compounds, and the symbol 0 (zero) means smaller than S.

[0048] TIFF0007894217000021.tif65164

[0049] The main effects of the component compounds are as follows: Compound (1) increases the upper temperature limit and elastic constant. Compound (2) increases dielectric anisotropy. Compound (3) increases the dielectric constant in the short axis direction. Compound (4) decreases viscosity or increases the upper temperature limit. Compound (5) increases the dielectric constant in the short axis direction.

[0050] Thirdly, the combinations of component compounds in the composition, preferred proportions, and the rationale for them will be explained. Preferred combinations of component compounds in the composition are compound (1) + compound (2) + compound (3), compound (1) + compound (2) + compound (3) + compound (4), compound (1) + compound (2) + compound (3) + compound (5), or compound (1) + compound (2) + compound (4) + compound (5). A particularly preferred combination is compound (1) + compound (2) + compound (3) + compound (4).

[0051] The preferred proportion of compound (1) is about 1% by mass or more to raise the upper temperature limit and elastic constant, and about 20% by mass or less to lower the lower temperature limit. A more preferred proportion is in the range of about 5% by mass to about 20% by mass. A particularly preferred proportion is in the range of about 5% by mass to about 15% by mass.

[0052] The preferred proportion of compound (2) is about 10% by mass or more to increase dielectric anisotropy, and about 85% by mass or less to lower the lower temperature limit. A more preferred proportion is in the range of about 10% by mass to about 70% by mass. A particularly preferred proportion is in the range of about 10% by mass to about 50% by mass.

[0053] The preferred proportion of compound (3) is about 10% by mass or more to increase the dielectric constant in the short axis direction, and about 50% by mass or less to lower the lower limit temperature. A more preferred proportion is in the range of about 10% by mass to about 40% by mass. A particularly preferred proportion is in the range of about 15% by mass to about 40% by mass.

[0054] The preferred proportion of compound (4) is about 10% by mass or more to lower viscosity or raise the upper temperature limit, and about 75% by mass or less to increase dielectric anisotropy. A more preferred proportion is in the range of about 20% by mass to about 70% by mass. A particularly preferred proportion is in the range of about 30% by mass to about 65% by mass.

[0055] The preferred proportion of compound (5) is about 1% by mass or more to increase the dielectric constant in the short axis direction, and about 30% by mass or less to lower the lower limit temperature. A more preferred proportion is in the range of about 1% by mass to about 25% by mass. A particularly preferred proportion is in the range of about 1% by mass to about 20% by mass.

[0056] Fourth, preferred forms of the component compounds will be described. In formulas (1), (2), (3), (4), and (5), R 1 R is an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms. Preferred R 1 The alkyl group has 1 to 12 carbon atoms to increase stability. Particularly preferred R 1 It is propyl. 2 is an alkenyl having 2 to 12 carbon atoms. Preferred R 2 It is vinyl. 3 R 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. Preferred R 3 To increase stability, it is an alkyl group with 1 to 12 carbon atoms. 4 and R 5 R 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, or an alkenyloxy group having 2 to 12 carbon atoms. Preferred R 4 or R 5 The carbon atoms are alkyl groups with 1 to 12 carbon atoms to increase stability, alkenyl groups with 2 to 12 carbon atoms to reduce viscosity, and alkoxy groups with 1 to 12 carbon atoms to increase dielectric anisotropy. 6 and R 7R 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 replaced by fluorine or chlorine. Preferred R 6 or R 7 The carbon atoms are alkenyls with 2 to 12 carbon atoms to lower viscosity or lower the lower limit temperature, and alkyls with 1 to 12 carbon atoms to increase stability. 8 and R 9 R 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, or an alkenyloxy group having 2 to 12 carbon atoms. Preferred R 8 or R 9 The alkyl group has 1 to 12 carbon atoms to increase stability, the alkenyl group has 2 to 12 carbon atoms to reduce viscosity, and the alkoxy group has 1 to 12 carbon atoms to increase dielectric anisotropy.

[0057] Preferred alkyl groups are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or octyl. More preferred alkyl groups are methyl, ethyl, propyl, butyl, or pentyl to reduce viscosity.

[0058] Preferred alkoxys are methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, or heptyloxy. For lower viscosity, even more preferred alkoxys are methoxy or ethoxy.

[0059] Preferred alkenyls 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. More preferred alkenyls are vinyl, 1-propenyl, 3-butenyl, or 3-pentenyl to reduce viscosity. The preferred stereochemistry of the -CH=CH- in these alkenyls depends on the position of the double bond. Trans is preferred for alkenyls such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, 3-pentenyl, and 3-hexenyl, for example, to reduce viscosity. Cis is preferred for alkenyls such as 2-butenyl, 2-pentenyl, and 2-hexenyl.

[0060] Preferred alkenyloxys are vinyloxy, allyloxy, 3-butenyloxy, 3-pentenyloxy, or 4-pentenyloxy. For lower viscosity, even more preferred alkenyloxys are allyloxy or 3-butenyloxy.

[0061] Preferred examples of alkyl groups in which at least one hydrogen atom is replaced by fluorine or chlorine are fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, 5-fluoropentyl, 6-fluorohexyl, 7-fluoroheptyl, or 8-fluorooctyl. Even more preferred examples are 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, or 5-fluoropentyl to increase dielectric anisotropy.

[0062] Preferred examples of alkenyls in which at least one hydrogen atom is replaced 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. Even more preferred examples are 2,2-difluorovinyl or 4,4-difluoro-3-butenyl for reducing viscosity.

[0063] Ring A is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl. Preferred ring A is 1,4-cyclohexylene to raise the upper temperature limit, 1,4-phenylene to increase optical anisotropy, and 2,6-difluoro-1,4-phenylene to increase dielectric anisotropy. Tetrahydropyran-2,5-diyl is TIFF0007894217000022.tif1123 or TIFF0007894217000023.tif1123 Preferably TIFF0007894217000024.tif1123 That is the case.

[0064] Rings B, D, and G are 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene with at least one hydrogen replaced by fluorine or chlorine, naphthalene-2,6-diyl, naphthalene-2,6-diyl with at least one hydrogen replaced by fluorine or chlorine, chroman-2,6-diyl, or chroman-2,6-diyl with at least one hydrogen replaced by fluorine or chlorine. Preferred examples of "1,4-phenylene with at least one hydrogen replaced by fluorine or chlorine" are 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, or 2-chloro-3-fluoro-1,4-phenylene. Preferred rings B, D, or G are 1,4-cyclohexylene to reduce viscosity, tetrahydropyran-2,5-diyl to increase dielectric anisotropy, and 1,4-phenylene to increase optical anisotropy. Tetrahydropyran-2,5-diyl in rings B, D, and G are TIFF0007894217000025.tif1323 or TIFF0007894217000026.tif1321 Preferably TIFF0007894217000027.tif1321 That is the case.

[0065] Ring C is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diyl, 7,8-difluorochroman-2,6-diyl, 3,4,5,6-tetrafluorofluorene-2,7-diyl (FLF4), or 1,1,6,7-tetrafluoroindan-2,5-diyl (InF4). The preferred ring C is 2,3-difluoro-1,4-phenylene to increase the dielectric constant in the short axis direction.

[0066] Rings E and F are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene. Preferred rings E or F are 1,4-cyclohexylene to lower viscosity or raise the upper temperature limit, and 1,4-phenylene or 2-fluoro-1,4-phenylene to increase optical anisotropy or lower the lower temperature limit.

[0067] Ring I is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diyl, 7,8-difluorochroman-2,6-diyl, 3,4,5,6-tetrafluorofluorene-2,7-diyl (FLF4), 4,6-difluorodibenzofuran-3,7-diyl (DBFF2), 4,6-difluorodibenzothiophene-3,7-diyl (DBTF2), or 1,1,6,7-tetrafluoroindan-2,5-diyl (InF4). TIFF0007894217000028.tif28166 The preferred ring I is 2,3-difluoro-1,4-phenylene to reduce viscosity, and 4,6-difluorodibenzothiophen-3,7-diyl to increase dielectric anisotropy.

[0068] Z 1 Z is a single bond or vinylene. 2 is a single bond, ethylene, vinylene, carbonyloxy, or difluoromethyleneoxy. Preferred Z 2 It is a single bond to reduce viscosity and a difluoromethyleneoxy to increase dielectric anisotropy. 3 , Z 4 , and Z 6 is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy. Preferred Z 3 , Z 4 , or Z 6 It is a single bond to reduce viscosity, ethylene to lower the lower limit temperature, and methyleneoxy to increase dielectric anisotropy. 5 is a single bond, ethylene, methyleneoxy, or carbonyloxy. Preferred Z 5 It has a single bond to reduce viscosity.

[0069] Divalent groups such as methyleneoxy are asymmetrical. In methyleneoxy, -CH2O- is preferred over -OCH2-. In carbonyloxy, -COO- is preferred over -OCO-. In difluoromethyleneoxy, -CF2O- is preferred over -OCF2-.

[0070] X 1 and X 2 X is either hydrogen or fluorine. Preferred X 1 or X 2 The element used is fluorine, which is used to increase dielectric anisotropy.

[0071] Y 1This is fluorine, chlorine, a C1 to C12 alkyl group in which at least one hydrogen is replaced by fluorine or chlorine, a C1 to C12 alkoxy group in which at least one hydrogen is replaced by fluorine or chlorine, or a C2 to C12 alkenyloxy group in which at least one hydrogen is replaced by fluorine or chlorine. Preferred Y 1 To increase dielectric anisotropy, the element is fluorine, a C1 to C12 alkyl group in which at least one hydrogen is replaced with fluorine or chlorine, or a C1 to C12 alkoxy group in which at least one hydrogen is replaced with fluorine or chlorine. A preferred example of an alkyl group in which at least one hydrogen is replaced with fluorine or chlorine is trifluoromethyl. A preferred example of an alkoxy group in which at least one hydrogen is replaced with fluorine or chlorine is trifluoromethoxy.

[0072] a is 1, 2, 3, or 4. Preferred a is 2 to lower viscosity and 3 to increase dielectric anisotropy. b is 1, 2, or 3, c is 0 or 1, and the sum of b and c is 2 or 3. Preferred combinations of b and c are b is 1 and c is 1, or b is 2 and c is 0. d is 1, 2, or 3. Preferred d is 1 to lower viscosity and 2 or 3 to raise the upper temperature limit. e is 0 or 1.

[0073] In equation (4), d is 2 and there are two Z 5 When the bond is a single bond, ring F is 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene.

[0074] Fifth, preferred component compounds are shown. Preferred compound (1) is compound (1-1) and compound (1-2) described in item 2. 1 Compounds in which (1-1) is propyl and R 1 Compounds (1-2) in which the compound is propyl are particularly preferred. Preferably, at least two of component A are a combination of compound (1-1) and compound (1-2).

[0075] Preferred compound (2) is compound (2-1) to compound (2-36) as described in item 4. In these compounds, it is preferable that at least one of component B is compound (2-2), compound (2-8), compound (2-13), compound (2-15), compound (2-16), compound (2-17), compound (2-19), compound (2-23), compound (2-24), compound (2-25), compound (2-27), compound (2-28), compound (2-30), or compound (2-31). It is even more preferable that at least one of component B is compound (2-19) or compound (2-30). It is preferable that at least two of component B are a combination of compound (2-2) and compound (2-19), compound (2-2) and compound (2-24), compound (2-2) and compound (2-25), compound (2-2) and compound (2-30), compound (2-19) and compound (2-24), compound (2-19) and compound (2-25), or compound (2-19) and compound (2-30). It is particularly preferable that at least two of component B are a combination of compound (2-19) and compound (2-30).

[0076] Preferred compound (3) is compound (3-1) to compound (3-20) as described in item 6. In these compounds, it is preferable that at least one of component C is compound (3-1), compound (3-2), compound (3-3), compound (3-7), compound (3-12), compound (3-13), or compound (3-14). It is particularly preferable that at least one of component C is compound (3-1) or compound (3-7). At least one of component C is R 4 Compounds in which C2 is an alkenyl with 2 to 4 carbon atoms (3-1) or R 4 It is particularly preferable that the compound (3-7) is an alkenyl having 2 to 4 carbon atoms. It is preferable that at least two of component C are a combination of compound (3-1) and compound (3-7).

[0077] Preferred compound (4) is compounds (4-1) to (4-13) described in item 9. In these compounds, it is preferred that at least one of component D is compound (4-1), compound (4-3), compound (4-5), compound (4-6), compound (4-7), compound (4-8), or compound (4-10). It is particularly preferred that at least one of component D is compound (4-1), compound (4-5), compound (4-8), or compound (4-10). R 6 and R 7 Compound (4) in which at least one of them is alkenyl having 2 to 4 carbon atoms is preferred. R 6 and R 7 Compound (4-1) in which they are propyl, vinyl, or 1-propenyl is preferred. R 6 is propyl or 1-propenyl and R 7 Compound (4-1) in which is vinyl is particularly preferred. R 7 The proportion of compound (4-1) in which is vinyl is preferably 30% by mass or more, and particularly preferably 40% by mass or more.

[0078] Preferred compound (5) is compounds (5-1) to (5-15) described in item 12. In these compounds, it is preferred that at least one of component E is compound (5-1), compound (5-2), compound (5-3), compound (5-6), or compound (5-7).

[0079] Compound (2) in which ring A is 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, or 1,3-dioxane-2,5-diyl is preferred, and the total proportion of these compounds and compound (3) is preferably 20% by mass or more, and particularly preferably 25% by mass or more.

[0080] Sixth, additives that may be added to the composition will be described. Such additives include optically active compounds, antioxidants, ultraviolet absorbers, quenchers, dyes, defoamers, polymerizable compounds, polymerization initiators, polymerization inhibitors, and polar compounds. Optically active compounds are added to the composition for the purpose of inducing a helical structure in liquid crystal molecules and giving them a twist angle. Examples of such compounds are compounds (6-1) to (6-5). A preferred proportion of optically active compounds 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.

[0081] TIFF0007894217000029.tif169153

[0082] To prevent a decrease in resistivity due to 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 temperature after prolonged use of the element, antioxidants such as compounds (7-1) to (7-3) may be further added to the composition.

[0083] TIFF0007894217000030.tif87126

[0084] Compound (7-2) has low volatility, making it 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 device. The preferred proportion of the antioxidant is approximately 50 ppm or more to obtain its effect, and approximately 600 ppm or less to avoid lowering the upper limit temperature or raising the lower limit temperature. A more preferred proportion is in the range of approximately 100 ppm to approximately 300 ppm.

[0085] Preferred examples of UV absorbers include benzophenone derivatives, benzoate derivatives, and triazole derivatives. Light stabilizers such as sterically hindered amines are also preferred. Preferred examples of light stabilizers include compounds (8-1) to (8-16). The preferred proportion of these absorbers and stabilizers is about 50 ppm or more to obtain their effect, and about 10,000 ppm or less to avoid lowering the upper temperature limit or raising the lower temperature limit. A more preferred proportion is in the range of about 100 ppm to about 10,000 ppm.

[0086] TIFF0007894217000031.tif251139

[0087] TIFF0007894217000032.tif245138

[0088] A quencher is a compound that prevents the decomposition of a liquid crystalline compound by receiving the light energy absorbed by the liquid crystalline compound and converting it into thermal energy. Preferred examples of quenchers are compounds (9-1) to (9-7), etc. The preferred proportion of these quenchers is about 50 ppm or more to obtain their effect, and about 20,000 ppm or less to avoid raising the lower limit temperature. A more preferred proportion is in the range of about 100 ppm to about 10,000 ppm.

[0089] TIFF0007894217000033.tif15880

[0090] To adapt the element to GH (guest host) 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, defoaming agents such as dimethyl silicone oil and methylphenyl silicone oil are added to the composition. The preferred proportion of the defoaming agent is about 1 ppm or more to obtain its effect, and about 1000 ppm or less to prevent display defects. A more preferred proportion is in the range of about 1 ppm to about 500 ppm.

[0091] Polymerizable compounds are used to adapt polymer-supported orientation (PSA) type elements. Preferred examples of such polymerizable compounds include acrylates, methacrylates, vinyl compounds, vinyloxy compounds, propenyl ethers, epoxy compounds (oxiran, oxetane), and vinyl ketones. More preferred examples are derivatives of acrylates or methacrylates. A preferred proportion is about 10% by mass or more, based on the total mass of the polymerizable compound. A more preferred proportion is about 50% by mass or more. A particularly preferred proportion is about 80% by mass or more. The most preferred proportion is 100% by mass.

[0092] When storing polymerizable compounds, polymerization inhibitors may be added to prevent polymerization. Polymerizable compounds are usually added to compositions without removing the polymerization inhibitor. Examples of polymerization inhibitors include hydroquinone, hydroquinone derivatives such as methylhydroquinone, 4-t-butylcatechol, 4-methoxyphenol, and phenothiazine.

[0093] Polar compounds are organic compounds that possess polarity. Compounds with ionic bonds are not included here. Atoms such as oxygen, sulfur, and nitrogen tend to be more electronegative and have a partial negative charge. Carbon and hydrogen tend to be neutral or have a partial positive charge. Polarity arises from the uneven distribution of partial charges between different types of atoms in a compound. For example, polar compounds have at least one of the following substructures: -OH, -COOH, -SH, -NH2, >NH, >N-.

[0094] 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. Compound (1-1) is synthesized by the method described in German Patent Application Publication No. 4414647. Compound (2-19) is synthesized by the method described in Japanese Patent Publication No. 10-251186. Compounds (3-1) and (5-1) are synthesized by the method described in Japanese Patent Publication No. 2-503441. Compound (4-1) is synthesized by the method described in Japanese Patent Publication No. 59-176221. Antioxidants are commercially available. Compound (7-1) is available from Sigma-Aldrich Corporation. Compounds (7-2), etc., are synthesized by the method described in U.S. Patent No. 3660505.

[0095] Compounds for which the synthesis method is not described can be synthesized by methods described in textbooks such as *Organic Syntheses* (John Wiley & Sons, Inc.), *Organic Reactions* (John Wiley & Sons, Inc.), *Comprehensive Organic Synthesis* (Pergamon Press), and *New Experimental Chemistry Course* (Maruzen). Compositions are prepared from the compounds obtained in this way by known methods. For example, component compounds are mixed and then dissolved by heating.

[0096] Finally, the uses of the composition will be described. This composition primarily has a lower temperature limit of about -10°C or lower, an upper temperature limit of about 70°C or higher, and an optical anisotropy in the range of about 0.07 to about 0.20. By controlling the proportion of component compounds or by mixing in other liquid crystalline compounds, compositions with an optical anisotropy in the range of about 0.08 to about 0.25 may be prepared. By trial and error, compositions with an optical anisotropy in the range of about 0.10 to about 0.30 may be prepared. 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 composition having a nematic phase, or as an optically active composition by adding optically active compounds.

[0097] This composition can be used in AM elements. Furthermore, it can also be used in PM elements. This composition can be used in AM and PM elements having modes such as PC, TN, STN, ECB, OCB, IPS, FFS, VA, and FPA. Use in AM elements having TN, OCB, IPS, or FFS modes is particularly preferred. In AM elements having IPS or FFS modes, when no voltage is applied, the arrangement of liquid crystal molecules may be parallel or perpendicular to the glass substrate. These elements may be reflective, transmissive, or semi-transmissive. Use in transmissive elements is preferred. It can also be used in amorphous silicon-TFT elements or polycrystalline silicon-TFT elements. It can also be used in NCAP (nematic curvilinear aligned phase) type elements fabricated by microencapsulating this composition, and in PD (polymer dispersed) type elements in which a three-dimensional network polymer is formed in the composition. [Examples]

[0098] The present invention will be described in more detail by way of examples. The present invention is not limited by these examples. The present invention includes a mixture of the composition of Example 1 and the composition of Example 2. The present invention also includes a mixture obtained by mixing at least two of the compositions of the examples. The synthesized compounds were identified by methods such as NMR analysis. The properties of the compounds, compositions, and devices were measured by the methods described below.

[0099] NMR analysis: For the measurement, DRX-500 manufactured by Bruker BioSpin was used. 1 For the measurement of 1H-NMR, the sample was dissolved in a deuterated solvent such as CDCl3, and the measurement was carried out at room temperature under the conditions of 500 MHz and 16 integration times. Tetramethylsilane was used as an internal standard. 19 For the measurement of 19F-NMR, CFCl3 was used as an internal standard and the measurement was carried out with 24 integration times. In the description of the nuclear magnetic resonance spectrum, s means singlet, d means doublet, t means triplet, q means quartet, quin means quintet, sex means sextet, m means multiplet, and br means broad.

[0100] Gas chromatographic analysis: For the measurement, a GC-14B type gas chromatograph manufactured by Shimadzu Corporation was used. The carrier gas was helium (2 mL / min). The sample vaporization chamber was set at 280 °C and the detector (FID) was set at 300 °C. For the separation of the component compounds, a capillary column DB-1 (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm; stationary liquid phase is dimethylpolysiloxane; nonpolar) manufactured by Agilent Technologies Inc. was used. This column was held at 200 °C for 2 minutes and then heated to 280 °C at a rate of 5 °C / min. The sample was prepared as an acetone solution (0.1 mass%) and then 1 μL of it was injected into the sample vaporization chamber. The recorder was a C-R5A type Chromatopac manufactured by Shimadzu Corporation or its equivalent. The obtained gas chromatogram showed the retention time and the area of the peak corresponding to the component compound.

[0101] The solvent used to dilute the sample may be chloroform, hexane, or other solvents. The following capillary columns may be used to separate the component compounds: HP-1 from Agilent Technologies Inc. (length 30m, inner diameter 0.32mm, film thickness 0.25μm), Rtx-1 from Restek Corporation (length 30m, inner diameter 0.32mm, film thickness 0.25μm), and BP-1 from SGE International Pty. Ltd (length 30m, inner diameter 0.32mm, film thickness 0.25μm). To prevent overlapping of compound peaks, a capillary column CBP1-M50-025 from Shimadzu Corporation (length 50m, inner diameter 0.25mm, film thickness 0.25μm) may also be used.

[0102] The proportion of liquid crystalline compounds contained in a composition may be calculated by the following method: Analyze the mixture of liquid crystalline compounds by gas chromatography (FID). The ratio of peak areas in the gas chromatogram corresponds to the proportion of liquid crystalline compounds. When using the capillary column described above, the correction factor for each liquid crystalline compound may be considered as 1. Therefore, the proportion (mass%) of liquid crystalline compounds can be calculated from the ratio of peak areas.

[0103] Measurement Samples: When measuring the properties of a composition or device, the composition was used as the sample. When measuring the properties of a compound, a sample for measurement was prepared by mixing the compound (15% by mass) with a mother liquid crystal (85% by mass). The property values ​​of the compound were calculated from the values ​​obtained by measurement using an extrapolation method. (Extrapolated value) = {(Measured value of sample) - 0.85 × (Measured value of mother liquid crystal)} / 0.15. When the smectic phase (or crystal) precipitated at 25°C in this ratio, the ratio of compound to mother liquid crystal was changed in the order of 10% by mass:90% by mass, 5% by mass:95% by mass, and 1% by mass:99% by mass. The upper temperature limit, optical anisotropy, viscosity, and dielectric anisotropy values ​​for the compound were determined using this extrapolation method.

[0104] The following mother liquid crystals were used. The proportions of the component compounds are shown in mass percent. TIFF0007894217000034.tif6098

[0105] Measurement Method: The characteristics were measured using the following methods. Many of these methods were those described in the JEITA standard (JEITA-ED-2521B), which is deliberated and established by the Japan Electronics and Information Technology Industries Association (JEITA), or modified versions thereof. Thin-film transistors (TFTs) were not attached to the TN elements used for measurement.

[0106] (1) Upper limit temperature of the nematic phase (NI; °C): The sample was placed on a hot plate of a melting point analyzer equipped with a polarizing microscope and heated at a rate of 1 °C / min. The temperature at which a portion of the sample changed from the nematic phase to an isotropic liquid was measured. The upper limit temperature of the nematic phase is sometimes abbreviated as "upper limit temperature".

[0107] (2) Lower limit temperature of the nematic phase (T C ;℃): Samples having a nematic phase were placed in glass bottles and stored in freezers at 0℃, -10℃, -20℃, -30℃, and -40℃ for 10 days, after which the liquid crystal phase was observed. For example, when the sample remained in the nematic phase at -20℃ and changed to a crystalline or smectic phase at -30℃, T C This was written as <-20℃. The lower limit temperature of the nematic phase is sometimes abbreviated as "lower limit temperature".

[0108] (3) Viscosity (bulk viscosity; η; measured at 20°C; mPa·s): An E-type rotational viscometer manufactured by Tokyo Keiki Co., Ltd. was used for measurement.

[0109] (4-1) Viscosity (rotational viscosity; γ1(25); measured at 25℃; mPa·s): The measurement was performed according to the method described in M. Imai et al., Molecular Crystals and Liquid Crystals, Vol. 259, 37 (1995). The sample was placed in a TN element with a twist angle of 0° and a cell gap of 5 μm between the two glass substrates. A voltage was applied to this element in steps of 0.5V in the range of 16V to 19.5V. After a 0.2 second period of no application, the application was repeated under the condition of only one square wave (square pulse; 0.2 seconds) followed by no 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 from these measurements and the calculation formula (10) described on page 40 of the paper by M. Imai et al. The dielectric anisotropy value required for this calculation was determined using the element whose rotational viscosity was measured, and the method described below was used.

[0110] (4-2) Viscosity (rotational viscosity; γ1(-30); measured at -30℃; mPa·s): Same as (4-1), except that it was measured at -30℃.

[0111] (5) Optical anisotropy (refractive index anisotropy; Δn; measured at 25°C): The measurement was performed using light with a wavelength of 589 nm and an Abbe refractometer with a polarizer attached to the eyepiece. After rubbing the surface of the main prism in one direction, the sample was dropped onto the main prism. 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 from the formula Δn = n∥ - n⊥.

[0112] (6) Dielectric Anisotropy (Δε; measured at 25℃): A sample was placed in a TN element with a cell gap of 9 μm between two glass substrates and a twist angle of 80 degrees. A sine wave (10V, 1kHz) was applied to this element, and the dielectric constant (ε∥) in the long axis direction of the liquid crystal molecules was measured after 2 seconds. A sine wave (0.5V, 1kHz) was applied to this element, and the dielectric constant (ε⊥) in the short axis direction of the liquid crystal molecules was measured after 2 seconds. The value of dielectric anisotropy was calculated from the formula Δε = ε∥ - ε⊥.

[0113] (7-1) Threshold voltage (Vth(25); measured at 25℃; V): An LCD5100 luminance meter manufactured by Otsuka Electronics Co., Ltd. was used for measurement. The light source was a halogen lamp. The sample was placed in an FFS element with a cell gap of 3.2 μm between two glass substrates. The voltage (32 Hz, square wave) applied to this element was increased stepwise from 0V to 10V in increments of 0.01V. At this time, light was shone onto the element from a direction perpendicular to it, and the amount of light transmitted through the element was measured. A voltage-transmittance curve was created where the maximum light intensity was 100% transmittance and the minimum light intensity was 0% transmittance. The threshold voltage was expressed as the voltage at which the transmittance reached 90%.

[0114] (7-2) Threshold voltage (Vth(-30); measured at -30℃; V): Same as (7-1) except that it was measured at -30℃.

[0115] (8) Voltage retention rate (VHR-9; measured at 25°C; %): The TN element used for the measurement had a polyimide orientation film, and the gap between the two glass substrates (cell gap) was 5 μm. After placing the sample inside the element, it was sealed with an adhesive that hardens with ultraviolet light. This TN element was charged by applying a pulse voltage (1V for 60 microseconds). The decaying voltage was measured with a high-speed voltmeter for 1000 milliseconds, and the area A between the voltage curve and the horizontal axis in a unit period was determined. Area B was the area when there was no decay. The voltage retention rate was expressed as the percentage of area A to area B.

[0116] (9) Voltage retention rate (VHR-10; measured at 60°C; %): The voltage retention rate was measured using the same procedure as above, except that it was measured at 60°C instead of 25°C. The obtained value was expressed as VHR-10.

[0117] (10) Voltage retention rate (VHR-11; measured at 60°C; %): After irradiation with ultraviolet light, the voltage retention rate was measured to evaluate the stability against ultraviolet light. The TN element used for the measurement had a polyimide oriented film and a cell gap of 5 μm. The sample was injected into this element and irradiated at 5 mW / cm². 2 The samples were irradiated with ultraviolet light for 167 minutes. The light source was a black light manufactured by iGraphics Co., Ltd., model F40T10 / BL (peak wavelength 369nm), and the distance between the element and the light source was 5mm. In the VHR-11 measurement, the voltage decay over 1000 milliseconds was measured. Compositions with a large VHR-11 have high stability against ultraviolet light.

[0118] (11) Voltage retention rate (VHR-12; measured at 60°C; %): After heating the TN element with the sample injected in a constant temperature bath at 120°C for 20 hours, the voltage retention rate was measured to evaluate thermal stability. For VHR-12 measurement, the voltage that decayed over 1000 milliseconds was measured. Compositions with a large VHR-12 have great thermal stability.

[0119] (12) Voltage retention rate (VHR-13; measured at 60°C; %): After heating the TN element with the sample implanted in a constant temperature bath at 100°C for 3 weeks, the voltage retention rate was measured to evaluate thermal stability. For VHR-13 measurement, the voltage that decayed over 1000 milliseconds was measured. Compositions with a high VHR-13 have high thermal stability.

[0120] (13) Voltage retention rate (VHR-14; measured at 60°C; %): After the TN elements with the injected sample were left standing on the backlight for two weeks, the voltage retention rate was measured to evaluate the stability against the backlight. For the VHR-14 measurement, the voltage that decayed over 1000 milliseconds was measured. Compositions with a high VHR-14 have greater stability against the backlight.

[0121] (14-1) Response time (τ(25); measured at 25℃; ms): An LCD5100 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 5kHz. The sample was placed in an FFS element with a cell gap of 3.2μm between two glass substrates. A square wave (60Hz, 5V, 0.5 seconds) was applied to this element. At this time, light was shone onto the element from a direction perpendicular to it, and the amount of light transmitted through the element was measured. When the amount of light was at its maximum, the transmittance was considered to be 100%, and when the amount of light was at its minimum, the transmittance was considered to be 0%. The rise time (τr; milliseconds) is the time required for the transmittance to change from 90% to 10%. The fall time (τf; milliseconds) is the time required for the transmittance to change from 10% to 90%. The response time was expressed as the sum of the rise time and fall time obtained in this way.

[0122] (14-2) Response time (τ(-30); measured at -30℃; ms): Measured at -30℃, the same as in (14-1), except that the square wave application conditions were changed (60Hz, 5V, 15 seconds).

[0123] (15) Elastic constant (K; measured at 25℃; pN): An HP4284A LCR meter manufactured by Yokogawa-Hewlett-Packard Corporation was used for the measurement. The sample was placed in a horizontally aligned element with a cell gap of 20 μm between two glass substrates. A charge from 0 volts to 20 volts was applied to this element, and the capacitance and applied voltage were measured. The measured 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 from equation (2.99). Next, K22 was calculated using the previously obtained values ​​of K11 and K33 in equation (3.18) on page 171 of the same handbook. The elastic constant was expressed as the average value of K11, K22, and K33 obtained in this way.

[0124] (16) Resistivity (ρ; measured at 25℃; Ωcm): 1.0 mL of the sample was injected into a container equipped with electrodes. A DC voltage (10V) was applied to this container, and the DC current was measured after 10 seconds. The resistivity was calculated from the following formula: (Resistivity) = {(Voltage) × (Capacitance of the container)} / {(DC current) × (Permittivity of vacuum)}.

[0125] (17) Helical pitch (P; measured at room temperature; μm): The helical pitch was measured using the wedge method. See "Liquid Crystal Handbook," page 196 (published in 2000 by Maruzen). The sample was injected into a wedge-shaped cell and left to stand at room temperature for 2 hours. The spacing between the disclination lines (d2-d1) was then observed using a polarizing microscope (Nikon Corporation, product name MM40 / 60 series). The helical pitch (P) was calculated from the following formula, where θ is the angle of the wedge cell: P = 2 × (d2-d1) × tanθ.

[0126] (18) Dielectric constant in the short axis direction (ε⊥; measured at 25°C): The sample was placed in a TN element with a 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 this element, and the dielectric constant (ε⊥) in the short axis direction of the liquid crystal molecules was measured after 2 seconds.

[0127] (19) Frequency dependence of dielectric anisotropy (F10; measured at -20°C): A sample was placed in a TN element with a 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 this element, and the dielectric constant (ε⊥) in the short axis direction of the liquid crystal molecules was measured after 2 seconds. F10 was defined as the frequency at which the dielectric anisotropy decreased by 10% compared to the dielectric anisotropy at 100Hz. A larger F10 indicates a smaller frequency dependence.

[0128] Examples of the composition are shown below. Component compounds are represented by symbols based on the definitions in Table 3 below. In Table 3, the stereochemistry of 1,4-cyclohexylene is trans. The number in parentheses after the symbolized compound indicates the chemical formula to which the compound belongs. The symbol (-) indicates other liquid crystalline compounds. The percentage of liquid crystalline compounds is the mass percentage (mass%) based on the mass of the liquid crystalline composition without additives. Finally, the characteristic values ​​of the composition are summarized.

[0129] TIFF0007894217000035.tif248156

[0130] [Comparative Example 1] A composition not containing compound (1) was prepared. 3-BB(F)B(F,F)XB(F,F)-F (2-30) 3% 4-BB(F)B(F,F)XB(F,F)-F (2-30) 8% 5-BB(F)B(F,F)XB(F,F)-F (2-30) 5% V-HHB(2F,3F)-O2 (3-1) 6% 3-HBB(2F,3F)-O2 (3-7) 5% V-HBB(2F,3F)-O2 (3-7) 5% 3-HH-V (4-1) 35.5% V-HH-V1 (4-1) 7% 3-HH-V1 (4-1) 4.5% V-HHB-1 (4-5) 10% V2-HHB-1 (4-5) 3% V-HBB-2 (4-6) 1% 1-BB(F)B-2V (4-8) 1% V-HHBB-2 (4-10) 6% NI = 105.2 °C; Tc < -20 °C; Δn = 0.111; Δε = 2.7; ε⊥ / Δε = 1.3; Vth(25) = 2.81 V; Vth(-30) = 3.52 V; γ1(25) = 73.7 mPa·s; γ1(-30) = 2835.5 mPa·s; τ(25) = 25.2 ms; τ(-30) = 669.5 ms; F10 = 260 Hz.

[0131] [Example 1] 3-HHH-V (l-1) 5% 3-HHB-OCF3 (2-2) 5% 3-BB(F,F)XB(F,F)-F (2-19) 3.5% 3-HBBXB(F,F)-F (2-24) 2%<00ZZ609>3-HBB(F,F)XB(F,F)-F (2-25) 1% 3-BB(F)B(F,F)XB(F,F)-F (2-30) 2% 4-BB(F)B(F,F)XB(F,F)-F (2-30) 6% 5-BB(F)B(F,F)XB(F,F)-F (2-30) 1.5% 3-HHB(2F,3F)-O2 (3-1) 5% 3-HBB(2F,3F)-O2 (Z-7) 5% 4-HBB(2F,3F)-O2 (3-7) 1% V-HBB(2F,3F)-O2 (3-7) 5% 3-HH-V (4-1) 36% V-HH-V1 (4-1) 10% V-HHB-1 (4-5) 2%<0000ZZ0>1-BB(F)B-2V (4-8) 3% 2-BB(F)B-2V (4-8) 2% V-HHBB-2 (4-10) 5% [[ID=Z1]]<Z0006Z3>NI=105.3℃;Tc<-40℃;Δn=0.111;Δε=2.7;ε⊥ / Δε=1.3;Vth(25)=2.85V;Vth(-30)=3.32V;γ1(25)=67.2mPa ·s;γ1(-30)=2311.5mPa·s;τ(25)=23.2ms;τ(-30)=539.5ms;F10=330Hz;VHR-10=95.1%;VHR-14=79.7%.

[0132] [Example 2] 3-HHH-V (1-1) 3% 3-HHVH-V (1-2) 8% 3-HHB-OCF3 (2-2) 1.5% 3-BB(F,F)XB(F,F)-F (2-19) 8% 3-BB(F)B(F,F)XB(F,F)-F (2-30) 3% 4-BB(F)B(F,F)XB(F,F)-F (2-30) 5% V-HHB(2F,3F)-O2 (3-1) 6% 3-HBB(2F,3F)-O2 (3-7) 5% V-HBB(2F,3F)-O2 (3-7) 5% 3-HH-V (4-1) 36% V-HH-V1 (4-1) 8.5% 1-BB(F)B-2V (4-8) 3% 2-BB(F)B-2V (4-8) 3% V-HHBB-2 (4-10) 5% NI=104.3℃;Tc<-40℃;Δn=0.111;Δε=2.6;ε⊥ / Δε=1.4;Vth(25)=2.83V;Vth(-30)=3.02V;γ1(25)=71.0mPa ·s;γ1(-30)=2154.1mPa·s;τ(25)=23.6ms;τ(-30)=494.3ms;F10=570Hz;VHR-10=94.8%;VHR-14=79.3%.

[0133] The physical properties of Comparative Example 1, Example 1, and Example 2 are shown in Table 4. TIFF0007894217000036.tif70106

[0134] Regarding the threshold voltage (Vth), it was confirmed that in Comparative Example 1, the value at -30°C was shifted 0.71V higher than the value at 25°C. On the other hand, in Examples 1 and 2, the shift was limited to 0.47V and 0.19V, respectively, and it was confirmed that at -30°C, Examples 1 and 2 had lower voltages than Comparative Example 1. When comparing Comparative Example 1 with Examples 1 and 2 regarding rotational viscosity (γ1), it was confirmed that Examples 1 and 2 had lower rotational viscosity, and particularly at -30°C, they had significantly lower rotational viscosity. When comparing Comparative Example 1 with Examples 1 and 2 regarding the response (τ), it was confirmed that Examples 1 and 2 had shorter response times, and particularly at -30°C, they had significantly shorter response times.

[0135] Figure 1 is a graph showing the frequency dependence of dielectric anisotropy at -20°C. This shows that in Comparative Example 1, the dielectric anisotropy begins to decrease at lower frequencies. Comparing F10, Comparative Example 1 had a F10 of 260 Hz, while Examples 1 and 2 had F10s of 330 Hz and 570 Hz, respectively. This indicates that Examples 1 and 2 have a smaller frequency dependence of dielectric anisotropy at -20°C.

[0136] As described above, the composition of the present invention has excellent response characteristics, while ε⊥ / Δε was equal to or better than that of Comparative Example 1. In other words, the present invention makes it possible to significantly improve response characteristics while maintaining transmittance at or above the same level.

[0137] [Example 3] 3-HHH-V (1-1) 4% 3-HHVH-V (1-2) 8% 3-HHB-OCF3 (2-2) 4% 3-HHXB(F,F)-F (2-5) 1% 3-GB(F,F)XB(F,F)-F (2-15) 2% 3-BB(F)B(F,F)-F (2-16) 6% 2-HHBB(F,F)-F (2-20) 2% 3-HHBB(F,F)-F (2-20) 2% 3-GBB(F)B(F,F)-F (2-23) 2% 4-GBB(F)B(F,F)-F (2-23) 3% 3-BB(F,F)XB(F)B(F,F)-F (2-31) 4% V-HHB(2F,3F)-O2 (3-1) 3% 3-HBB(2F,3F)-O2 (3-7) 6% V-HBB(2F,3F)-O2 (3-7) 5% 3-HH-V (4-1) 38% 3-HH-V1 (4-1) 8% 1-BB(F)B-2V (4-8) 2% NI = 105.7 °C; Tc < -30 °C; Δn = 0.102; Δε = 3.0; ε⊥ / Δε = 1.3; γ1(25) = 83.7 mPa·s; γ1(-30) = 2600.0 mPa·s; τ(25) = 23.5 ms; τ(-30) = 614.0 ms.

[0138] [Example 4] 3-HHH-V (1-1) 3% 3-HHVH-V (1-2) 8% 3-BB(F,F)XB(F,F)-F (2-19) 6% 3-BB(F)B(F,F)XB(F,F)-F (2-30) 3% 4-BB(F)B(F,F)XB(F,F)-F (2-30) 7% V-HHB(2F,3F)-O2 (3-1) 6% 3-HBB(2F,3F)-O2 (3-7) 5% V-HBB(2F,3F)-O2 (3-7) 5%<​​​ 3-HH-V1 (4-1) 4.5% V-HHB-1 (4-5) 2% V-HBB-2 (4-6) 1% 1-BB(F)B-2V (4-8) 1% V-HHBB-2 (4-10) 6% NI = 105.8 °C; Tc < -40 °C; Δn = 0.102; Δε = 2.7; ε⊥ / Δε = 1.3; γ1(25) = 64.0 mPa·s; γ1(-30) = 2127.0 mPa·s; τ(25) = 23.6 ms; τ(-30) = 502.2 ms.[[ID=​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​[Example 6] 3-HHH-V (1-1) 3% 3-HHVH-V (1-2) 5% 3-HHB-OCF3 (2-2) 1.5% 3-GB(F,F)XB(F,F)-F (2-15) 5% 3-BB(F,F)XB(F,F)-F (2-19) 4% 3-GBB(F)B(F,F)-F (2-23) 2% 4-GBB(F)B(F,F)-F (2-23) 2% 3-BB(F)B(F,F)XB(F,F)-F (2-30) 3% V-HHB(2F,3F)-O2 (3-1) 6% 3-HBB(2F,3F)-O2 (3-7) 5% V-HBB(2F,3F)-O2 (3-7) 5% 3-HH-V (4-1) 30% V-HH-V1 (4-1) 8.5% 3-HH-V1 (4-1) 4% 1-BB-3 (4-3) 2% V-HHB-1 (4-5) 4% 1-BB(F)B-2V (4-8) 3% V-HHBB-2 (4-10) 5% 5-HBB(F)B-2 (4-13) 2% NI = 105.4 °C; Tc < -30 °C; Δn = 0.110; Δε = 3.8; ε⊥ / Δε = 1.4; γ1(25) = 69.0 mPa·s; γ1(-30) = 2512.0 mPa·s; τ(25) = 25.5 ms; τ(-30) = 573.6 ms.

[0141] [Example 7] 3-HHH-V (1-1) 4.5% 3-HBB(F,F)XB(F,F)-F (2-25) 6% 4-GB(F)B(F,F)XB(F,F)-F (2-28) 2% 3-BB(F)B(F,F)XB(F,F)-F (2-30) 3% 4-BB(F)B(F,F)XB(F,F)-F (2-30) 5% 3-HHB(2F,3F)-O2 (3-1) 5% 2-HBB(2F,3F)-O2 (3-7) 2% 3-HBB(2F,3F)-O2 (3-7) 5% V-HBB(2F,3F)-O2 (3-7) 5% 3-HH-V (4-1) 34% V-HH-V1 (4-1) 2.5% 3-HH-V1 (4-1) 6% 1-BB(F)B-2V (4-8) 3% 2-BB(F)B-2V (4-8) 5% 3-BB(F)B-2V (4-8) 5% V-HHBB-2 (4-10) 4% 3-BB(2F,3F)-O2 (5-6) 3% NI=106.0℃;Tc<-30℃;Δn=0.127;Δε=2.6;ε⊥ / Δε=1.5;γ1(25)=81.6mPa·s

[0142] The composition of the present invention and the liquid crystal display element using it are found to have excellent properties such as a large ε⊥ / Δε, low rotational viscosity, low threshold voltage, short response time, and small frequency dependence of dielectric anisotropy, and are particularly excellent at low temperatures. [Industrial applicability]

[0143] The liquid crystal composition of the present invention can be used in liquid crystal monitors, liquid crystal televisions, and the like.

Claims

1. A liquid crystal composition comprising, as component A, at least one compound selected from compounds represented by formula (1), as component B, at least one compound selected from compounds represented by formula (2), as component C, at least one compound selected from compounds represented by formula (3), and as component E, at least one compound selected from compounds represented by formula (5), wherein the proportion of component C is in the range of 10% by mass to 50% by mass, and having positive dielectric anisotropy. In equation (1), R １ R is an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms; ２ These are alkenyls with 2 to 12 carbon atoms; Z １ is a single bond or vinylene; In equation (2), 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; ring A is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; Z ２ X is a single bond, ethylene, vinylene, carbonyloxy, or difluoromethyleneoxy; １ and X ２ is hydrogen or fluorine; Y １ is fluorine, chlorine, a C1 to C12 alkyl group in which at least one hydrogen is replaced by fluorine or chlorine, a C1 to C12 alkoxy group in which at least one hydrogen is replaced by fluorine or chlorine, or a C2 to C12 alkenyloxy group in which at least one hydrogen is replaced by fluorine or chlorine; a is 1, 2, 3, or 4; In formula (3), R ４ and R ５ are hydrogen, alkyl having 1 to 12 carbon atoms, alkoxy having 1 to 12 carbon atoms, alkenyl having 2 to 12 carbon atoms, or alkenyloxy having 2 to 12 carbon atoms; ring B and ring D are 1,4 - cyclohexylene, 1,4 - cyclohexenylene, tetrahydropyran - 2,5 - diyl, 1,4 - phenylene, 1,4 - phenylene in which at least one hydrogen is replaced by fluorine or chlorine, naphthalene - 2,6 - diyl, naphthalene - 2,6 - diyl in which at least one hydrogen is replaced by fluorine or chlorine, chroman - 2,6 - diyl, or chroman - 2,6 - diyl in which at least one hydrogen is replaced by fluorine or chlorine; ring C is 2,3 - difluoro - 1,4 - phenylene, 2 - chloro - 3 - fluoro - 1,4 - phenylene, 2,3 - difluoro - 5 - methyl - 1,4 - phenylene, 3,4,5 - trifluoronaphthalene - 2,6 - diyl, 7,8 - difluorochroman - 2,6 - diyl, 3,4,5,6 - tetrafluorofluorene - 2,7 - diyl, or 1,1,6,7 - tetrafluorohydrindan - 2,5 - diyl; Z ３ and Z ４ are a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy; b is 1, 2, or 3, c is 0 or 1; and the sum of b and c is 2 or 3; In formula (5), R8 and R9 are hydrogen, a C1-C12 alkyl, a C1-C12 alkoxy, a C2-C12 alkenyl, or a C2-C12 alkenyloxy; ring G is 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,4-phenylene, 1,4-phenylene with at least one hydrogen replaced by fluorine or chlorine, naphthalene-2,6-diyl, naphthalene-2,6-diyl with at least one hydrogen replaced by fluorine or chlorine, chroman-2,6-diyl, or with at least one hydrogen replaced by fluorine or chlorine The substituted chroman-2,6-diyl; ring I is 2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diyl, 7,8-difluorochroman-2,6-diyl, 3,4,5,6-tetrafluorofluorene-2,7-diyl, 4,6-difluorodibenzofuran-3,7-diyl, 4,6-difluorodibenzothiophene-3,7-diyl, or 1,1,6,7-tetrafluoroindan-2,5-diyl; Z 6 is a single bond, ethylene, vinylene, methyleneoxy, or carbonyloxy; e is 0 or 1.

2. The liquid crystal composition according to claim 1, comprising, as component A, at least one compound selected from the compounds represented by formulas (1-1) and (1-2). In equations (1-1) and (1-2), R １ These are alkyl groups having 1 to 12 carbon atoms or alkenyl groups having 2 to 12 carbon atoms.

3. The liquid crystal composition according to claim 1 or 2, wherein the proportion of component A is in the range of 1% by mass to 20% by mass.

4. The liquid crystal composition according to any one of claims 1 to 3, comprising, as component B, at least one compound selected from the compounds represented by formulas (2-1) to (2-36). In equations (2-1) to (2-36), R ３ These are alkyl groups having 1 to 12 carbon atoms, alkoxy groups having 1 to 12 carbon atoms, or alkenyl groups having 2 to 12 carbon atoms.

5. The liquid crystal composition according to any one of claims 1 to 4, wherein the proportion of component B is in the range of 10% by mass to 85% by mass.

6. The liquid crystal composition according to any one of claims 1 to 5, comprising, as component C, at least one compound selected from the compounds represented by formulas (3-1) to (3-20). In equations (3-1) to (3-20), R ４ and R ５ These are hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyloxy group having 2 to 12 carbon atoms.

7. The liquid crystal composition according to any one of claims 1 to 6, comprising at least one compound selected from the compounds represented by formula (4) as component D. In equation (4), R ６ and R ７ 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 replaced by fluorine or chlorine; rings E and F are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene; Z ５ is a single bond, ethylene, methyleneoxy, or carbonyloxy; d is 1, 2, or 3; however, d is 2 and there are two Z ５ When the bond is a single bond, ring F is 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene.

8. The liquid crystal composition according to any one of claims 1 to 7, comprising, as component D, at least one compound selected from the compounds represented by formulas (4-1) to (4-13). In equations (4-1) to (4-13), R ６ and R ７ These are C1 to C12 alkyl groups, C1 to C12 alkoxy groups, C2 to C12 alkenyl groups, or C2 to C12 alkenyl groups in which at least one hydrogen atom is replaced by fluorine or chlorine.

9. The liquid crystal composition according to claim 7 or 8, wherein the proportion of component D is in the range of 10% by mass to 75% by mass.

10. The liquid crystal composition according to any one of claims 1 to 9, comprising, as component E, at least one compound selected from the compounds represented by formulas (5-1) to (5-15). In equations (5-1) to (5-15), R ８ and R ９ These are hydrogen, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyloxy group having 2 to 12 carbon atoms.

11. The liquid crystal composition according to any one of claims 1 to 10, wherein the proportion of component E is in the range of 1% by mass to 30% by mass.

12. A liquid crystal composition according to any one of claims 1 to 11, wherein the upper limit temperature of the nematic phase is 70°C or higher, the optical anisotropy at a wavelength of 589 nm (measured at 25°C) is 0.07 or higher, and the dielectric anisotropy at a frequency of 1 kHz (measured at 25°C) is 2.0 or higher.

13. The liquid crystal composition according to any one of claims 1 to 12, for use as a liquid crystal display element in which the operating mode is IPS mode or FFS mode.

14. A liquid crystal display element containing the liquid crystal composition according to any one of claims 1 to 12.

15. The liquid crystal display element according to claim 14, wherein the operating mode of the liquid crystal display element is TN mode, ECB mode, OCB mode, IPS mode, FFS mode, or FPA mode, and the driving method of the liquid crystal display element is an active matrix method.

16. Use of the liquid crystal composition according to any one of claims 1 to 12 in a liquid crystal display element.

Images