Liquid crystal composition, and liquid crystal display element, sensor, liquid crystal lens, and optical communication device using the same

Abstract

To provide: a liquid crystal composition, which has a large refractive index anisotropy (Δn) and in which all of liquid crystal phase upper limit temperature (TNI), liquid crystal phase lower limit temperature (T→N) and threshold potential (Vth) are good; and a liquid crystal display, a sensor, a liquid crystal lens, and optical communication equipment using the same.SOLUTION: Provided is a liquid crystal composition using one or two or more of specific three compounds in combination, which has a large refractive index anisotropy (Δn) and in which all of liquid crystal phase upper limit temperature (TNI), liquid crystal phase lower limit temperature (T→N) and threshold potential (Vth) are good.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a liquid crystal composition, and a liquid crystal display element, a sensor, a liquid crystal lens and an optical communication device using the same. [Background technology]

[0002] Liquid crystal display elements are used in a variety of applications, including watches and calculators, various measuring instruments, automotive panels, word processors, electronic organizers, printers, computers, televisions, clocks, and advertising displays. Representative liquid crystal display types include the TN (twisted nematic) type, the STN (super twisted nematic) type, the vertical alignment type using TFTs (thin film transistors), and the IPS (in-plane switching) type. In recent years, there has been a trend in these liquid crystal display elements to achieve faster operation by narrowing the cell gap (d) of the liquid crystal cell, but the value of the product (d x Δn) of the cell gap and the refractive index anisotropy (Δn), known as retardation, must be optimized. For this reason, narrowing the cell gap (reducing d) requires increasing the value of Δn, and liquid crystal compositions with a larger Δn value than existing liquid crystal compositions are in demand.

[0003] An example of an application device using a liquid crystal composition is a liquid crystal lens that utilizes the birefringence of a liquid crystal composition.

[0004] Liquid crystal lenses are made by sealing a liquid crystal composition that has been aligned using an alignment film between glass or film substrates, and applying a voltage to the liquid crystal composition to cause an orientation deformation and change the refractive index of the liquid crystal composition, thereby giving it a lens function. Liquid crystal lenses are used as 2D / 3D switching lenses, camera focus adjustment lenses, etc.

[0005] The substrates into which the liquid crystal composition is sealed may consist of a pair of typical flat substrates, or one of the substrates may be processed into a lens shape. When both substrates are flat, the electrodes are arranged in a special way to apply an electric field that orients the liquid crystal molecules in the liquid crystal composition sealed between the substrates in a lens-like shape, so that even though the substrates are flat, incident light passing through the substrates is refracted by the liquid crystal molecules in the liquid crystal composition that are oriented in a lens-like shape (Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2015-84077 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, in liquid crystal lenses, the larger the change in refractive index caused by the change in the orientation of the liquid crystal composition used, the greater the desired lens effect can be obtained with a thin cell, so the liquid crystal composition is required to have a large refractive index anisotropy (Δn). NI ), liquid crystal phase lower limit temperature (T →N Regarding other physical properties such as the luminance (luminance) and threshold voltage (Vth), liquid crystal compositions exhibiting values ​​sufficient for practical use have not been sufficiently investigated, and there is room for improvement in liquid crystal compositions.

[0008] The present invention relates to a liquid crystal material having a large refractive index anisotropy (Δn) and a liquid crystal phase upper limit temperature (T NI ), liquid crystal phase lower limit temperature (T →N The present invention aims to provide a liquid crystal composition which is excellent in both the refractive index (Vc) and threshold voltage (Vth), and a liquid crystal display element, a sensor, a liquid crystal lens, and an optical communication device each using the same. [Means for solving the problem]

[0009] As a result of intensive research, the present inventors have found that the above problems can be solved by using one or more of three specific types of compounds in combination, and have thus completed the present invention.

[0010] The present invention, which solves the above problems, is configured as follows.

[0011] The liquid crystal composition according to the present invention comprises The following general formula (i)

[0012] [ka]

[0013] (In general formula (i), R i1 and R i2 each independently represents an alkyl group having 1 to 20 carbon atoms, One or more -CH2- groups in the alkyl group may each independently be replaced by -O- or -CO-; one or more -CH2-CH2- in the alkyl group may each independently be replaced by -CH=CH-, -C≡C-, -CO-O- or -O-CO-; One or more hydrogen atoms in the alkyl group may be independently substituted with a halogen atom. Oxygen atoms do not bond directly to each other, L i1 represents -CO-O- or -O-CO-. and one or more compounds represented by the formula: The following general formula (ii)

[0014] [ka]

[0015] (In general formula (ii), R ii1 and R ii2each independently represents an alkyl group having 1 to 20 carbon atoms, One or more -CH2- groups in the alkyl group may each independently be replaced by -O- or -CO-; one or more -CH2-CH2- in the alkyl group may each independently be replaced by -CH=CH-, -C≡C-, -CO-O- or -O-CO-; One or more hydrogen atoms in the alkyl group may be independently substituted with a halogen atom. Oxygen atoms never bond directly to each other.) and one or more compounds represented by the formula: The following general formula (iii)

[0016] [ka]

[0017] (In general formula (iii), R iii1 and R iii2 each independently represents an alkyl group having 1 to 20 carbon atoms, One or more -CH2- groups in the alkyl group may each independently be replaced by -O- or -CO-; one or more -CH2-CH2- in the alkyl group may each independently be replaced by -CH=CH-, -C≡C-, -CO-O- or -O-CO-; One or more hydrogen atoms in the alkyl group may be independently substituted with a halogen atom. Oxygen atoms do not bond directly to each other, n iii1 represents an integer of 0 or 1. and one or more compounds represented by the formula: The present invention is characterized by comprising:

[0018] The liquid crystal display device according to the present invention is characterized by using the above-mentioned liquid crystal composition.

[0019] A sensor according to the present invention is characterized by using the above-mentioned liquid crystal composition.

[0020] A liquid crystal lens according to the present invention is characterized by using the above-mentioned liquid crystal composition.

[0021] The optical communication device according to the present invention is characterized by using the above-mentioned liquid crystal composition. Effect of the Invention

[0022] According to the present invention, by using one or more of three types of compounds in combination, a liquid crystal composition having a large refractive index anisotropy (Δn) and a liquid crystal phase upper limit temperature (T NI ), liquid crystal phase lower limit temperature (T →N It is possible to obtain a liquid crystal composition having good properties in both the liquid crystal display element, the liquid crystal sensor, the liquid crystal lens, and the optical communication device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] (Compound represented by general formula (i)) The liquid crystal composition according to the present invention contains one or more compounds represented by the following general formula (i) having a tolan structure and -CO-O- or -O-CO- as a linking group.

[0024] [ka]

[0025] In general formula (i), R i1 and R i2 each independently represents an alkyl group having 1 to 20 carbon atoms.

[0026] The alkyl group having 1 to 20 carbon atoms is a linear, branched or cyclic alkyl group, and is preferably a linear alkyl group.

[0027] The alkyl group having 1 to 20 carbon atoms preferably has 2 to 10 carbon atoms, and more preferably has 2 to 6 carbon atoms.

[0028] One or more -CH2- groups in the alkyl group may each independently be substituted by -O- or --CO-.

[0029] In addition, one or more -CH2-CH2- groups in the alkyl group may each independently be substituted by -CH=CH-, -C≡C-, -CO-O- or -O-CO-.

[0030] Furthermore, one or more hydrogen atoms in the alkyl group may each independently be substituted with a halogen atom.

[0031] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

[0032] However, when the alkyl group is substituted with a specific group, the oxygen atoms are not directly bonded to each other.

[0033] For example, R i1 and R i2 can represent an alkoxy group having 1 to 19 carbon atoms by replacing one -CH2- in the alkyl group with -O-.

[0034] The alkoxy group is a linear, branched or cyclic alkoxy group, and is preferably a linear alkoxy group.

[0035] The alkoxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0036] Also, R i1 and R i2 can represent an alkenyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -CH=CH-.

[0037] The alkenyl group is a linear, branched or cyclic alkenyl group, and is preferably a linear alkenyl group.

[0038] The alkenyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0039] Also, R i1 and R i2 can represent an alkynyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -C≡C-.

[0040] The alkynyl group may be a linear, branched or cyclic alkynyl group, and is preferably a linear alkynyl group.

[0041] The alkynyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0042] Also, R i1 and R i2 can represent an alkenyloxy group having 1 to 19 carbon atoms by replacing one -CH2- with -O- and one or more -CH2-CH2- with -CH=CH- in the alkyl group.

[0043] The alkenyloxy group is a linear, branched or cyclic alkenyloxy group, and is preferably a linear alkenyloxy group.

[0044] The alkenyloxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0045] Also, R i1 and R i2 can represent a halogenated alkyl group having 1 to 20 carbon atoms by substituting one or more hydrogen atoms in the alkyl group with halogen atoms.

[0046] The halogenated alkyl group may be linear, branched or cyclic, and is preferably a linear halogenated alkyl group.

[0047] The halogenated alkyl group preferably has 2-10 carbon atoms, and more preferably has 2-6 carbon atoms.

[0048] R i1 and R i2 Specific examples of the alkyl group having 1 to 20 carbon atoms (including substituted alkyl groups) in the formula (R i1 / 2 -1)~(R i1 / 2 -31) and the like.

[0049] [ka]

[0050] Formula (R i1 / 2 -1)~(R i1 / 2 -31), the black dots represent bonds to the ring structure.

[0051] In addition, R i1 and R i2 From the viewpoint of the viscosity of the liquid crystal composition, a linear alkyl group having 1 to 6 carbon atoms is preferable.

[0052] In general formula (i), L i1 represents -CO-O- or -O-CO-, and -CO-O- is preferred.

[0053] The compound represented by general formula (i) is preferably a compound represented by the following general formula (i-1).

[0054] [ka]

[0055] In general formula (i-1), R i1 and R i2 is R in the above general formula (i). i1 and Ri2 and the preferred groups are also the same.

[0056] The compound represented by general formula (i-1) is preferably a compound represented by the following structural formulas (i-1.1) to (i-1.2).

[0057] [ka]

[0058] The type of compound represented by general formula (i), general formula (i-1), or structural formulae (i-1.1) to (i-1.2) used in the liquid crystal composition is one or more types, preferably 1 to 5 types, preferably 1 to 4 types, preferably 1 to 3 types, preferably 1 to 2 types, and preferably 1 type.

[0059] The lower limit of the total content of the compounds represented by general formula (i), general formula (i-1), and structural formulas (i-1.1) to (i-1.2) in 100% by mass of the liquid crystal composition is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more.

[0060] The upper limit of the total content of the compounds represented by general formula (i), general formula (i-1), or structural formulas (i-1.1) to (i-1.2) in 100% by mass of the liquid crystal composition is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less.

[0061] The total content of the compounds represented by general formula (i), general formula (i-1), or structural formulas (i-1.1) to (i-1.2) in 100% by mass of the liquid crystal composition is preferably 1 to 25% by mass, more preferably 3 to 20% by mass, and even more preferably 5 to 15% by mass.

[0062] The compounds represented by general formula (i), general formula (i-1) or structural formulas (i-1.1) to (i-1.2) can be synthesized by using known synthesis methods. (Compound represented by general formula (ii)) The liquid crystal composition according to the present invention contains one or more compounds having a tolan structure and a straight ring structure and represented by the following general formula (ii).

[0063] [ka]

[0064] In general formula (ii), R ii1 and R ii2 each independently represents an alkyl group having 1 to 20 carbon atoms.

[0065] The alkyl group having 1 to 20 carbon atoms is a linear, branched or cyclic alkyl group, and is preferably a linear alkyl group.

[0066] The alkyl group having 1 to 20 carbon atoms preferably has 2 to 10 carbon atoms, and more preferably has 2 to 6 carbon atoms.

[0067] One or more -CH2- groups in the alkyl group may each independently be substituted by -O- or --CO-.

[0068] In addition, one or more -CH2-CH2- groups in the alkyl group may each independently be substituted by -CH=CH-, -C≡C-, -CO-O- or -O-CO-.

[0069] Furthermore, one or more hydrogen atoms in the alkyl group may each independently be substituted with a halogen atom.

[0070] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

[0071] However, when the alkyl group is substituted with a specific group, the oxygen atoms are not directly bonded to each other.

[0072] For example, R ii1 and R ii2can represent an alkoxy group having 1 to 19 carbon atoms by replacing one -CH2- in the alkyl group with -O-.

[0073] The alkoxy group is a linear, branched or cyclic alkoxy group, and is preferably a linear alkoxy group.

[0074] The alkoxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0075] Also, R ii1 and R ii2 can represent an alkenyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -CH=CH-.

[0076] The alkenyl group is a linear, branched or cyclic alkenyl group, and is preferably a linear alkenyl group.

[0077] The alkenyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0078] Also, R ii1 and R ii2 can represent an alkynyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -C≡C-.

[0079] The alkynyl group may be a linear, branched or cyclic alkynyl group, and is preferably a linear alkynyl group.

[0080] The alkynyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0081] Also, R ii1 and R ii2can represent an alkenyloxy group having 1 to 19 carbon atoms by replacing one -CH2- with -O- and one or more -CH2-CH2- with -CH=CH- in the alkyl group.

[0082] The alkenyloxy group is a linear, branched or cyclic alkenyloxy group, and is preferably a linear alkenyloxy group.

[0083] The alkenyloxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0084] Also, R ii1 and R ii2 can represent a halogenated alkyl group having 1 to 20 carbon atoms by substituting one or more hydrogen atoms in the alkyl group with halogen atoms.

[0085] The halogenated alkyl group may be linear, branched or cyclic, and is preferably a linear halogenated alkyl group.

[0086] The halogenated alkyl group preferably has 2-10 carbon atoms, and more preferably has 2-6 carbon atoms.

[0087] R ii1 and R ii2 Specific examples of the alkyl group having 1 to 20 carbon atoms (including substituted alkyl groups) in the formula (R ii1 / 2 -1)~(R ii1 / 2 -31) and the like.

[0088] [ka]

[0089] Formula (R ii1 / 2 -1)~(R ii1 / 2 -31), the black dots represent bonds to the ring structure.

[0090] In addition, R ii1 and R ii2 From the viewpoint of the viscosity of the liquid crystal composition, a linear alkyl group having 1 to 6 carbon atoms is preferable.

[0091] The compound represented by general formula (ii) is preferably a compound represented by the following structural formulas (ii.1) to (ii.5).

[0092] [ka]

[0093] The type of compound represented by general formula (ii) or structural formulas (ii.1) to (ii.5) used in the liquid crystal composition is one or more types, preferably 1 to 5 types, preferably 1 to 4 types, preferably 1 to 3 types, preferably 1 to 2 types, and preferably 1 type.

[0094] The lower limit of the total content of the compounds represented by general formula (ii) or structural formulas (ii.1) to (ii.5) in 100% by mass of the liquid crystal composition is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more.

[0095] The upper limit of the total content of the compounds represented by general formula (ii) or structural formulas (ii.1) to (ii.5) in 100% by mass of the liquid crystal composition is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less.

[0096] The total content of the compounds represented by general formula (ii) or structural formulas (ii.1) to (ii.5) in 100% by mass of the liquid crystal composition is preferably 1 to 30% by mass, more preferably 3 to 25% by mass, and even more preferably 5 to 20% by mass.

[0097] The compounds represented by general formula (ii) or structural formulas (ii.1) to (ii.5) can be synthesized by using known synthesis methods. (Compound represented by general formula (iii)) The liquid crystal composition according to the present invention contains one or more compounds represented by the following general formula (iii) having a tolan structure substituted with a methyl group.

[0098] [ka]

[0099] In general formula (iii), R iii1 and R iii2 each independently represents an alkyl group having 1 to 20 carbon atoms.

[0100] The alkyl group having 1 to 20 carbon atoms is a linear, branched or cyclic alkyl group, and is preferably a linear alkyl group.

[0101] The alkyl group having 1 to 20 carbon atoms preferably has 2 to 10 carbon atoms, and more preferably has 2 to 6 carbon atoms.

[0102] One or more -CH2- groups in the alkyl group may each independently be substituted by -O- or --CO-.

[0103] In addition, one or more -CH2-CH2- groups in the alkyl group may each independently be substituted by -CH=CH-, -C≡C-, -CO-O- or -O-CO-.

[0104] Furthermore, one or more hydrogen atoms in the alkyl group may each independently be substituted with a halogen atom.

[0105] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

[0106] However, when the alkyl group is substituted with a specific group, the oxygen atoms are not directly bonded to each other.

[0107] For example, R iii1 and Riii2 can represent an alkoxy group having 1 to 19 carbon atoms by replacing one -CH2- in the alkyl group with -O-.

[0108] The alkoxy group is a linear, branched or cyclic alkoxy group, and is preferably a linear alkoxy group.

[0109] The alkoxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0110] Also, R iii1 and R iii2 can represent an alkenyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -CH=CH-.

[0111] The alkenyl group is a linear, branched or cyclic alkenyl group, and is preferably a linear alkenyl group.

[0112] The alkenyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0113] Also, R iii1 and R iii2 can represent an alkynyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -C≡C-.

[0114] The alkynyl group may be a linear, branched or cyclic alkynyl group, and is preferably a linear alkynyl group.

[0115] The alkynyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0116] Also, R iii1 and R iii2can represent an alkenyloxy group having 1 to 19 carbon atoms by replacing one -CH2- with -O- and one or more -CH2-CH2- with -CH=CH- in the alkyl group.

[0117] The alkenyloxy group is a linear, branched or cyclic alkenyloxy group, and is preferably a linear alkenyloxy group.

[0118] The alkenyloxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0119] Also, R iii1 and R iii2 can represent a halogenated alkyl group having 1 to 20 carbon atoms by substituting one or more hydrogen atoms in the alkyl group with halogen atoms.

[0120] The halogenated alkyl group may be linear, branched or cyclic, and is preferably a linear halogenated alkyl group.

[0121] The halogenated alkyl group preferably has 2-10 carbon atoms, and more preferably has 2-6 carbon atoms.

[0122] R iii1 and R iii2 Specific examples of the alkyl group having 1 to 20 carbon atoms (including substituted alkyl groups) in the formula (R iii1 / 2 -1)~(R iii1 / 2 -31) and the like.

[0123] [ka]

[0124] Formula (R iii1 / 2 -1)~(R iii1 / 2 -31), the black dots represent bonds to the ring structure.

[0125] In addition, R iii1 and R iii2 From the viewpoint of the viscosity of the liquid crystal composition, a linear alkyl group having 1 to 6 carbon atoms or a linear alkoxy group having 1 to 6 carbon atoms is preferable as the alkyl group.

[0126] In general formula (iii), n iii1 represents an integer of 0 or 1.

[0127] The compound represented by general formula (iii) is preferably a compound represented by the following general formulas (iii-1) to (iii-2).

[0128] [ka]

[0129] In general formulas (iii-1) to (iii-2), R iii1 and R iii2 is R in the above general formula (iii). iii1 and R iii2 and the preferred groups are also the same.

[0130] The compound represented by general formula (iii-1) is preferably a compound represented by the following structural formulas (iii-1.1) to (iii-1.4).

[0131] [ka]

[0132] The compound represented by general formula (iii-2) is preferably a compound represented by the following structural formulas (iii-2.1) to (iii-2.2).

[0133] [ka]

[0134] The compounds represented by general formula (iii), general formulas (iii-1) to (iii-2), structural formulas (iii-1.1) to (iii-1.4), or structural formulas (iii-2.1) to (iii-2.2) used in the liquid crystal composition are one or more kinds, preferably 1 to 5 kinds, preferably 1 to 4 kinds, preferably 1 to 3 kinds, preferably 1 to 2 kinds, and preferably 1 kind.

[0135] The lower limit of the total content of the compounds represented by general formula (iii), general formulas (iii-1) to (iii-2), structural formulas (iii-1.1) to (iii-1.4), or structural formulas (iii-2.1) to (iii-2.2) in 100 mass% of the liquid crystal composition is preferably 1 mass% or more, more preferably 5 mass% or more, and even more preferably 10 mass% or more.

[0136] The upper limit of the total content of the compounds represented by general formula (iii), general formulas (iii-1) to (iii-2), structural formulas (iii-1.1) to (iii-1.4), or structural formulas (iii-2.1) to (iii-2.2) in 100% by mass of the liquid crystal composition is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less.

[0137] The total content of the compounds represented by general formula (iii), general formulas (iii-1) to (iii-2), structural formulas (iii-1.1) to (iii-1.4), or structural formulas (iii-2.1) to (iii-2.2) in 100% by mass of the liquid crystal composition is preferably 1 to 30% by mass, more preferably 5 to 25% by mass, and even more preferably 10 to 20% by mass.

[0138] The compounds represented by general formula (iii), general formulae (iii-1) to (iii-2), structural formulae (iii-1.1) to (iii-1.4), or structural formulae (iii-2.1) to (iii-2.2) can be synthesized by using a known synthesis method. (Other compounds) (Compound represented by general formula (iv)) The liquid crystal composition of the present invention may further contain one or more compounds represented by the following general formula (iv) having a fluorine-substituted terphenyl structure and a cyano group, from the viewpoint of increasing the refractive index anisotropy (Δn) and decreasing the threshold voltage (Vth).

[0139] [ka]

[0140] In general formula (iv), R iv1 each independently represents an alkyl group having 1 to 20 carbon atoms.

[0141] The alkyl group having 1 to 20 carbon atoms is a linear, branched or cyclic alkyl group, and is preferably a linear alkyl group.

[0142] The alkyl group having 1 to 20 carbon atoms preferably has 2 to 10 carbon atoms, and more preferably has 2 to 6 carbon atoms.

[0143] One or more -CH2- groups in the alkyl group may each independently be substituted by -O- or --CO-.

[0144] In addition, one or more -CH2-CH2- groups in the alkyl group may each independently be substituted by -CH=CH-, -C≡C-, -CO-O- or -O-CO-.

[0145] Furthermore, one or more hydrogen atoms in the alkyl group may each independently be substituted with a halogen atom.

[0146] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

[0147] However, when the alkyl group is substituted with a specific group, the oxygen atoms are not directly bonded to each other.

[0148] For example, Riv1 can represent an alkoxy group having 1 to 19 carbon atoms by replacing one -CH2- in the alkyl group with -O-.

[0149] The alkoxy group is a linear, branched or cyclic alkoxy group, and is preferably a linear alkoxy group.

[0150] The alkoxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0151] Also, R iv1 can represent an alkenyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -CH=CH-.

[0152] The alkenyl group is a linear, branched or cyclic alkenyl group, and is preferably a linear alkenyl group.

[0153] The alkenyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0154] Also, R iv1 can represent an alkynyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -C≡C-.

[0155] The alkynyl group may be a linear, branched or cyclic alkynyl group, and is preferably a linear alkynyl group.

[0156] The alkynyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0157] Also, R iv1can represent an alkenyloxy group having 1 to 19 carbon atoms by replacing one -CH2- with -O- and one or more -CH2-CH2- with -CH=CH- in the alkyl group.

[0158] The alkenyloxy group is a linear, branched or cyclic alkenyloxy group, and is preferably a linear alkenyloxy group.

[0159] The alkenyloxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0160] Also, R iv1 can represent a halogenated alkyl group having 1 to 20 carbon atoms by substituting one or more hydrogen atoms in the alkyl group with halogen atoms.

[0161] The halogenated alkyl group may be linear, branched or cyclic, and is preferably a linear halogenated alkyl group.

[0162] The halogenated alkyl group preferably has 2-10 carbon atoms, and more preferably has 2-6 carbon atoms.

[0163] R iv1 Specific examples of the alkyl group having 1 to 20 carbon atoms (including substituted alkyl groups) in the formula (R iv1 -1)~(R iv1 -31) and the like.

[0164] [ka]

[0165] Formula (R iv1 -1)~(R iv1 -31), the black dots represent bonds to the ring structure.

[0166] In addition, R iv1From the viewpoint of the viscosity of the liquid crystal composition, a linear alkyl group having 1 to 6 carbon atoms is preferable.

[0167] The compound represented by general formula (iv) is preferably a compound represented by the following structural formulas (iv.1) to (iv.3).

[0168] [ka]

[0169] The type of compound represented by general formula (iv) or structural formulae (iv.1) to (iv.3) used in the liquid crystal composition is one or more types, preferably 1 to 5 types, preferably 1 to 4 types, preferably 1 to 3 types, preferably 1 to 2 types, and preferably 1 type.

[0170] The lower limit of the total content of the compounds represented by general formula (iv) or structural formulas (iv.1) to (iv.3) in 100% by mass of the liquid crystal composition is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 3% by mass or more.

[0171] The upper limit of the total content of the compounds represented by general formula (iv) or structural formulas (iv.1) to (iv.3) in 100% by mass of the liquid crystal composition is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less.

[0172] The total content of the compounds represented by general formula (iv) or structural formulas (iv.1) to (iv.3) in 100% by mass of the liquid crystal composition is preferably 1 to 30% by mass, more preferably 2 to 25% by mass, and even more preferably 3 to 20% by mass.

[0173] The compounds represented by the general formula (iv) or the structural formulae (iv.1) to (iv.3) can be synthesized by using a known synthesis method. (Compound represented by general formula (v)) From the viewpoint of adjusting the threshold voltage (Vth), the liquid crystal composition according to the present invention may further contain one or more compounds represented by the following general formula (v) having a cyano group and a structure in which two ring structures are directly bonded.

[0174] [ka]

[0175] In general formula (v), R v1 each independently represents an alkyl group having 1 to 20 carbon atoms.

[0176] The alkyl group having 1 to 20 carbon atoms is a linear, branched or cyclic alkyl group, and is preferably a linear alkyl group.

[0177] The alkyl group having 1 to 20 carbon atoms preferably has 2 to 10 carbon atoms, and more preferably has 2 to 6 carbon atoms.

[0178] One or more -CH2- groups in the alkyl group may each independently be substituted by -O- or --CO-.

[0179] In addition, one or more -CH2-CH2- groups in the alkyl group may each independently be substituted by -CH=CH-, -C≡C-, -CO-O- or -O-CO-.

[0180] Furthermore, one or more hydrogen atoms in the alkyl group may each independently be substituted with a halogen atom.

[0181] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

[0182] However, when the alkyl group is substituted with a specific group, the oxygen atoms are not directly bonded to each other.

[0183] For example, R v1can represent an alkoxy group having 1 to 19 carbon atoms by replacing one -CH2- in the alkyl group with -O-.

[0184] The alkoxy group is a linear, branched or cyclic alkoxy group, and is preferably a linear alkoxy group.

[0185] The alkoxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0186] Also, R v1 can represent an alkenyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -CH=CH-.

[0187] The alkenyl group is a linear, branched or cyclic alkenyl group, and is preferably a linear alkenyl group.

[0188] The alkenyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0189] Also, R v1 can represent an alkynyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -C≡C-.

[0190] The alkynyl group may be a linear, branched or cyclic alkynyl group, and is preferably a linear alkynyl group.

[0191] The alkynyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0192] Also, R v1 can represent an alkenyloxy group having 1 to 19 carbon atoms by replacing one -CH2- with -O- and one or more -CH2-CH2- with -CH=CH- in the alkyl group.

[0193] The alkenyloxy group is a linear, branched or cyclic alkenyloxy group, and is preferably a linear alkenyloxy group.

[0194] The alkenyloxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0195] Also, R v1 can represent a halogenated alkyl group having 1 to 20 carbon atoms by substituting one or more hydrogen atoms in the alkyl group with halogen atoms.

[0196] The halogenated alkyl group may be linear, branched or cyclic, and is preferably a linear halogenated alkyl group.

[0197] The halogenated alkyl group preferably has 2-10 carbon atoms, and more preferably has 2-6 carbon atoms.

[0198] R v1 Specific examples of the alkyl group having 1 to 20 carbon atoms (including substituted alkyl groups) in the formula (R v1 -1)~(R v1 -31) and the like.

[0199] [ka]

[0200] Formula (R v1 -1)~(R v1 -31), the black dots represent bonds to the ring structure.

[0201] In addition, R v1 From the viewpoint of the viscosity of the liquid crystal composition, a linear alkyl group having 1 to 6 carbon atoms is preferable.

[0202] In general formula (v), A v1 and Av2 each independently represents the following group (a) and group (b): (a) a 1,4-cyclohexylene group (in which one -CH2- or two or more non-adjacent -CH2- groups may be replaced by -O- and / or -S-). (b) a 1,4-phenylene group (in which one -CH= or two or more non-adjacent -CH= groups may be replaced by -N=). represents a group selected from the group consisting of:

[0203] Also, A v1 and A v2 One or more hydrogen atoms therein may each be independently substituted by a halogen atom.

[0204] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0205] A v2 The halogen atom may be substituted at any of the positions shown in the following formula (A v2 -SP-1)~(A v2 -SP-2).

[0206] [ka]

[0207] Formula (A v2 -SP-1)~(A v2 -SP-2) Medium, X v1 Each independently represents a halogen atom, and the white dots represent A v1 The black dots represent bonds to the cyano group (-CN).

[0208] More specifically, A v1 is expressed by the following formula (A v1 -1)~(A v1 -3) is preferable.

[0209] [ka]

[0210] Formula (A v1 -1)~(A v1 -3) Medium, white dots are R v1 The black dots represent bonds to A. v2 Represents a bond to .

[0211] More specifically, A v2 is expressed by the following formula (A v2 -1)~(A v2 -3) is preferable.

[0212] [ka]

[0213] Formula (A v2 -1)~(A v2 -3) Medium, white dots are A v1 The black dots represent bonds to the cyano group (-CN).

[0214] The compound represented by general formula (v) is preferably a compound represented by the following general formulas (v-1) to (v-5).

[0215] [ka]

[0216] In general formulas (v-1) to (v-5), R v1 R in the above general formula (v) v1 The preferred groups are also the same as those mentioned above.

[0217] In addition, in the general formulas (v-1) to (v-5), X v1 each independently represents a halogen atom.

[0218] The compound represented by general formula (v-1) is preferably a compound represented by the following structural formula (v-1.1).

[0219] [ka]

[0220] The compound represented by general formula (v-2) is preferably a compound represented by the following structural formulas (v-2.1) to (v-2.2).

[0221] [ka]

[0222] The compound represented by general formula (v-3) is preferably a compound represented by the following structural formula (v-3.1).

[0223] [ka]

[0224] The compound represented by general formula (v-4) is preferably a compound represented by the following structural formula (v-4.1).

[0225] [ka]

[0226] The compound represented by general formula (v-5) is preferably a compound represented by the following structural formula (v-5.1).

[0227] [ka]

[0228] The type of compound represented by general formula (v), general formulas (v-1) to (v-5), structural formula (v-1.1), structural formula (v-2.1) to (v-2.2), structural formula (v-3.1), structural formula (v-4.1) or structural formula (v-5.1) used in the liquid crystal composition is one or more types, preferably 1 to 5 types, preferably 1 to 4 types, preferably 1 to 3 types, preferably 1 to 2 types, and preferably 1 type.

[0229] The lower limit of the total content of the compounds represented by general formula (v), general formulas (v-1) to (v-5), structural formulas (v-1.1), structural formulas (v-2.1) to (v-2.2), structural formula (v-3.1), structural formula (v-4.1) or structural formula (v-5.1) in 100% by mass of the liquid crystal composition is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more.

[0230] The upper limit of the total content of the compounds represented by general formula (v), general formulas (v-1) to (v-5), structural formulas (v-1.1), structural formulas (v-2.1) to (v-2.2), structural formula (v-3.1), structural formula (v-4.1) or structural formula (v-5.1) in 100% by mass of the liquid crystal composition is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less.

[0231] The total content of the compounds represented by general formula (v), general formulas (v-1) to (v-5), structural formula (v-1.1), structural formula (v-2.1) to (v-2.2), structural formula (v-3.1), structural formula (v-4.1) or structural formula (v-5.1) in 100% by mass of the liquid crystal composition is preferably 0.1 to 30% by mass, more preferably 0.5 to 25% by mass, and even more preferably 1 to 20% by mass.

[0232] The compounds represented by general formula (v), general formulae (v-1) to (v-5), structural formula (v-1.1), structural formula (v-2.1) to (v-2.2), structural formula (v-3.1), structural formula (v-4.1) or structural formula (v-5.1) can be synthesized by using a known synthesis method. (Compound represented by general formula (vi)) The liquid crystal composition of the present invention may further contain one or more compounds represented by the following general formula (vi) having a fluorine atom and a cyano group, from the viewpoint of increasing the refractive index anisotropy (Δn) and decreasing the threshold voltage (Vth).

[0233] [ka]

[0234] In general formula (vi), R vi1 each independently represents an alkyl group having 1 to 20 carbon atoms.

[0235] The alkyl group having 1 to 20 carbon atoms is a linear, branched or cyclic alkyl group, and is preferably a linear alkyl group.

[0236] The alkyl group having 1 to 20 carbon atoms preferably has 2 to 10 carbon atoms, and more preferably has 2 to 6 carbon atoms.

[0237] One or more -CH2- groups in the alkyl group may each independently be substituted by -O- or --CO-.

[0238] In addition, one or more -CH2-CH2- groups in the alkyl group may each independently be substituted by -CH=CH-, -C≡C-, -CO-O- or -O-CO-.

[0239] Furthermore, one or more hydrogen atoms in the alkyl group may each independently be substituted with a halogen atom.

[0240] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

[0241] However, when the alkyl group is substituted with a specific group, the oxygen atoms are not directly bonded to each other.

[0242] For example, R vi1can represent an alkoxy group having 1 to 19 carbon atoms by replacing one -CH2- in the alkyl group with -O-.

[0243] The alkoxy group is a linear, branched or cyclic alkoxy group, and is preferably a linear alkoxy group.

[0244] The alkoxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0245] Also, R vi1 can represent an alkenyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -CH=CH-.

[0246] The alkenyl group is a linear, branched or cyclic alkenyl group, and is preferably a linear alkenyl group.

[0247] The alkenyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0248] Also, R vi1 can represent an alkynyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -C≡C-.

[0249] The alkynyl group may be a linear, branched or cyclic alkynyl group, and is preferably a linear alkynyl group.

[0250] The alkynyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0251] Also, R vi1 can represent an alkenyloxy group having 1 to 19 carbon atoms by replacing one -CH2- with -O- and one or more -CH2-CH2- with -CH=CH- in the alkyl group.

[0252] The alkenyloxy group is a linear, branched or cyclic alkenyloxy group, and is preferably a linear alkenyloxy group.

[0253] The alkenyloxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0254] Also, R vi1 can represent a halogenated alkyl group having 1 to 20 carbon atoms by substituting one or more hydrogen atoms in the alkyl group with halogen atoms.

[0255] The halogenated alkyl group may be linear, branched or cyclic, and is preferably a linear halogenated alkyl group.

[0256] The halogenated alkyl group preferably has 2-10 carbon atoms, and more preferably has 2-6 carbon atoms.

[0257] R vi1 Specific examples of the alkyl group having 1 to 20 carbon atoms (including substituted alkyl groups) in the formula (R vi1 -1)~(R vi1 -31) and the like.

[0258] [ka]

[0259] Formula (R vi1 -1)~(R vi1 -31), the black dots represent bonds to the ring structure.

[0260] In addition, R vi1 From the viewpoint of the viscosity of the liquid crystal composition, a linear alkyl group having 1 to 6 carbon atoms is preferable.

[0261] In general formula (vi), L vi1represents -CO-O- or -O-CO-, with -CO-O- being preferred.

[0262] In general formula (vi), X vi1 represents a hydrogen atom or a fluorine atom.

[0263] In general formula (vi), n vi1 represents an integer of 0 or 1.

[0264] The compound represented by general formula (vi) is preferably a compound represented by the following general formulas (vi-1) to (vi-3).

[0265] [ka]

[0266] In general formulas (vi-1) to (vi-3), R vi1 is R in the above general formula (vi). vi1 and the preferred groups are also the same.

[0267] The compound represented by general formula (vi-1) is preferably a compound represented by the following structural formulas (vi-1.1) to (vi-1.4).

[0268] [ka]

[0269] The compound represented by general formula (vi-2) is preferably a compound represented by the following structural formulas (vi-2.1) to (vi-2.4).

[0270] [ka]

[0271] The compound represented by general formula (vi-3) is preferably a compound represented by the following structural formulas (vi-3.1) to (vi-3.4).

[0272] [ka]

[0273] The compounds represented by general formula (vi), general formulae (vi-1) to (vi-3), structural formulae (vi-1.1) to (vi-1.4), structural formulae (vi-2.1) to (vi-2.4) or structural formulae (vi-3.1) to (vi-3.4) used in the liquid crystal composition are one or more kinds, preferably 1 to 5 kinds, preferably 1 to 4 kinds, preferably 1 to 3 kinds, preferably 1 to 2 kinds, and preferably 1 kind.

[0274] The lower limit of the total content of the compounds represented by general formula (vi), general formulas (vi-1) to (vi-3), structural formulas (vi-1.1) to (vi-1.4), structural formulas (vi-2.1) to (vi-2.4), or structural formulas (vi-3.1) to (vi-3.4) in 100 mass% of the liquid crystal composition is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, and even more preferably 1 mass% or more.

[0275] The upper limit of the total content of the compounds represented by general formula (vi), general formulae (vi-1) to (vi-3), structural formulae (vi-1.1) to (vi-1.4), structural formulae (vi-2.1) to (vi-2.4), or structural formulae (vi-3.1) to (vi-3.4) in 100% by mass of the liquid crystal composition is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less.

[0276] The total content of the compounds represented by general formula (vi), general formulas (vi-1) to (vi-3), structural formulas (vi-1.1) to (vi-1.4), structural formulas (vi-2.1) to (vi-2.4) or structural formulas (vi-3.1) to (vi-3.4) in 100% by mass of the liquid crystal composition is preferably 0.1 to 25% by mass, more preferably 0.5 to 20% by mass, and even more preferably 1 to 15% by mass.

[0277] The compounds represented by general formula (vi), general formulae (vi-1) to (vi-3), structural formulae (vi-1.1) to (vi-1.4), structural formulae (vi-2.1) to (vi-2.4) or structural formulae (vi-3.1) to (vi-3.4) can be synthesized by using a known synthesis method. (Compound represented by general formula (vii)) The liquid crystal composition according to the present invention has a large refractive index anisotropy (Δn) and a liquid crystal phase upper limit temperature (T NI ), one or more compounds having a tolan structure and represented by the following general formula (vii) may further be contained.

[0278] [ka]

[0279] In general formula (vii), R vii1 and R vii2 each independently represents an alkyl group having 1 to 20 carbon atoms.

[0280] The alkyl group having 1 to 20 carbon atoms is a linear, branched or cyclic alkyl group, and is preferably a linear alkyl group.

[0281] The alkyl group having 1 to 20 carbon atoms preferably has 2 to 10 carbon atoms, and more preferably has 2 to 6 carbon atoms.

[0282] One or more -CH2- groups in the alkyl group may each independently be substituted by -O- or --CO-.

[0283] In addition, one or more -CH2-CH2- groups in the alkyl group may each independently be substituted by -CH=CH-, -C≡C-, -CO-O- or -O-CO-.

[0284] Furthermore, one or more hydrogen atoms in the alkyl group may each independently be substituted with a halogen atom.

[0285] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

[0286] However, when the alkyl group is substituted with a specific group, the oxygen atoms are not directly bonded to each other.

[0287] For example, R vii1 and R vii2 can represent an alkoxy group having 1 to 19 carbon atoms by replacing one -CH2- in the alkyl group with -O-.

[0288] The alkoxy group is a linear, branched or cyclic alkoxy group, and is preferably a linear alkoxy group.

[0289] The alkoxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0290] Also, R vii1 and R vii2 can represent an alkenyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -CH=CH-.

[0291] The alkenyl group is a linear, branched or cyclic alkenyl group, and is preferably a linear alkenyl group.

[0292] The alkenyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0293] Also, R vii1 and R vii2 can represent an alkynyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -C≡C-.

[0294] The alkynyl group may be a linear, branched or cyclic alkynyl group, and is preferably a linear alkynyl group.

[0295] The alkynyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0296] Also, R vii1 and R vii2 can represent an alkenyloxy group having 1 to 19 carbon atoms by replacing one -CH2- with -O- and one or more -CH2-CH2- with -CH=CH- in the alkyl group.

[0297] The alkenyloxy group is a linear, branched or cyclic alkenyloxy group, and is preferably a linear alkenyloxy group.

[0298] The alkenyloxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0299] Also, R vii1 and R vii2 can represent a halogenated alkyl group having 1 to 20 carbon atoms by substituting one or more hydrogen atoms in the alkyl group with halogen atoms.

[0300] The halogenated alkyl group may be linear, branched or cyclic, and is preferably a linear halogenated alkyl group.

[0301] The halogenated alkyl group preferably has 2-10 carbon atoms, and more preferably has 2-6 carbon atoms.

[0302] R vii1 and R vii2 Specific examples of the alkyl group having 1 to 20 carbon atoms (including substituted alkyl groups) in the formula (R vii1 / 2 -1)~(R vii1 / 2 -31) and the like.

[0303] [ka]

[0304] Formula (R vii1 / 2 -1)~(R vii1 / 2 -31), the black dots represent bonds to the ring structure.

[0305] In addition, R vii1 and R vii2 From the viewpoint of viscosity of the liquid crystal composition, a linear alkyl group having 1 to 6 carbon atoms, a linear alkoxy group having 1 to 6 carbon atoms, or a linear alkenyl group having 1 to 6 carbon atoms is preferred.

[0306] The compound represented by general formula (vii) is preferably a compound represented by the following structural formulas (vii-1.1) to (vii-1.5).

[0307] [ka]

[0308] The type of compound represented by general formula (vii) or structural formulae (vii-1.1) to (vii-1.5) used in the liquid crystal composition is one or more types, preferably 1 to 5 types, preferably 1 to 4 types, preferably 1 to 3 types, preferably 1 to 2 types, and preferably 1 type.

[0309] The lower limit of the total content of the compounds represented by general formula (vii) or structural formulas (vii-1.1) to (vii-1.5) in 100% by mass of the liquid crystal composition is preferably 15% by mass or more, more preferably 20% by mass or more, and even more preferably 25% by mass or more.

[0310] The upper limit of the total content of the compounds represented by general formula (vii) or structural formulas (vii-1.1) to (vii-1.5) in 100% by mass of the liquid crystal composition is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less.

[0311] The total content of the compounds represented by general formula (vii) or structural formulae (vii-1.1) to (vii-1.5) in 100% by mass of the liquid crystal composition is preferably 15 to 50% by mass, more preferably 20 to 45% by mass, and even more preferably 25 to 40% by mass.

[0312] The compounds represented by general formula (vii) or structural formulas (vii-1.1) to (vii-1.5) can be synthesized by using known synthesis methods. (Compound represented by general formula (viii)) The liquid crystal composition according to the present invention is characterized by its compatibility and liquid crystal phase minimum temperature (T →N ), the compound may further include one or more compounds represented by the following general formula (viii), which has a structure in which a cyclohexyl structure and a phenylene structure are bonded via -CO-O- or -O-CO- as a linking group.

[0313] [ka]

[0314] In general formula (viii), R viii1 and R viii2 each independently represents an alkyl group having 1 to 20 carbon atoms.

[0315] The alkyl group having 1 to 20 carbon atoms is a linear, branched or cyclic alkyl group, and is preferably a linear alkyl group.

[0316] The alkyl group having 1 to 20 carbon atoms preferably has 2 to 10 carbon atoms, and more preferably has 2 to 6 carbon atoms.

[0317] One or more -CH2- groups in the alkyl group may each independently be substituted by -O- or --CO-.

[0318] In addition, one or more -CH2-CH2- groups in the alkyl group may each independently be substituted by -CH=CH-, -C≡C-, -CO-O- or -O-CO-.

[0319] Furthermore, one or more hydrogen atoms in the alkyl group may each independently be substituted with a halogen atom.

[0320] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

[0321] However, when the alkyl group is substituted with a specific group, the oxygen atoms are not directly bonded to each other.

[0322] For example, R viii1 and R viii2 can represent an alkoxy group having 1 to 19 carbon atoms by replacing one -CH2- in the alkyl group with -O-.

[0323] The alkoxy group is a linear, branched or cyclic alkoxy group, and is preferably a linear alkoxy group.

[0324] The alkoxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0325] Also, R viii1 and R viii2 can represent an alkenyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -CH=CH-.

[0326] The alkenyl group is a linear, branched or cyclic alkenyl group, and is preferably a linear alkenyl group.

[0327] The alkenyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0328] Also, R viii1 and R viii2 can represent an alkynyl group having 1 to 20 carbon atoms by replacing one or more -CH2-CH2- in the alkyl group with -C≡C-.

[0329] The alkynyl group may be a linear, branched or cyclic alkynyl group, and is preferably a linear alkynyl group.

[0330] The alkynyl group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0331] Also, R viii1 and R viii2 can represent an alkenyloxy group having 1 to 19 carbon atoms by replacing one -CH2- with -O- and one or more -CH2-CH2- with -CH=CH- in the alkyl group.

[0332] The alkenyloxy group is a linear, branched or cyclic alkenyloxy group, and is preferably a linear alkenyloxy group.

[0333] The alkenyloxy group preferably has 2-10, and more preferably 2-6, carbon atoms.

[0334] Also, R viii1 and R viii2 can represent a halogenated alkyl group having 1 to 20 carbon atoms by substituting one or more hydrogen atoms in the alkyl group with halogen atoms.

[0335] The halogenated alkyl group may be linear, branched or cyclic, and is preferably a linear halogenated alkyl group.

[0336] The halogenated alkyl group preferably has 2-10 carbon atoms, and more preferably has 2-6 carbon atoms.

[0337] R viii1 and R viii2 Specific examples of the alkyl group having 1 to 20 carbon atoms (including substituted alkyl groups) in the formula (R viii1 / 2 -1)~(R viii1 / 2 -31) and the like.

[0338] [ka]

[0339] Formula (R viii1 / 2 -1)~(R viii1 / 2 -31), the black dots represent bonds to the ring structure.

[0340] In addition, R viii1 and R viii2 From the viewpoint of viscosity of the liquid crystal composition, a linear alkyl group having 1 to 6 carbon atoms or a linear alkoxy group having 1 to 6 carbon atoms is preferable as the alkyl group.

[0341] In general formula (viii), L viii1 represents -CO-O- or -O-CO-, with -CO-O- being preferred.

[0342] In general formula (viii), n viii1 and n viii2 each independently represents an integer of 0 or 1.

[0343] The compound represented by general formula (viii) is preferably a compound represented by the following general formulas (viii-1) to (viii-2).

[0344] [ka]

[0345] In general formulas (viii-1) to (viii-2), R viii1 and R viii2 is R in the above general formula (viii). viii1 and R viii2and the preferred groups are also the same.

[0346] The compound represented by general formula (viii-1) is preferably a compound represented by the following structural formula (viii-1.1).

[0347] [ka]

[0348] The compound represented by general formula (viii-2) is preferably a compound represented by the following structural formulas (viii-2.1) to (viii-2.4).

[0349] [ka]

[0350] The compounds represented by general formula (viii), general formulae (viii-1) to (viii-2), structural formula (viii-1.1) or structural formulae (viii-2.1) to (viii-2.4) used in the liquid crystal composition are one or more kinds, preferably 1 to 5 kinds, preferably 1 to 4 kinds, preferably 1 to 3 kinds, preferably 1 to 2 kinds, and preferably 1 kind.

[0351] The lower limit of the total content of the compounds represented by general formula (viii), general formulae (viii-1) to (viii-2), structural formula (viii-1.1), or structural formulae (viii-2.1) to (viii-2.4) in 100 mass% of the liquid crystal composition is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, and even more preferably 1 mass% or more.

[0352] The upper limit of the total content of the compounds represented by general formula (viii), general formulae (viii-1) to (viii-2), structural formula (viii-1.1), or structural formulae (viii-2.1) to (viii-2.4) in 100% by mass of the liquid crystal composition is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less.

[0353] The total content of the compounds represented by general formula (viii), general formulae (viii-1) to (viii-2), structural formula (viii-1.1) or structural formulae (viii-2.1) to (viii-2.4) in 100% by mass of the liquid crystal composition is preferably 0.1 to 25% by mass, more preferably 0.5 to 20% by mass, and even more preferably 1 to 15% by mass.

[0354] The compounds represented by general formula (viii), general formulae (viii-1) to (viii-2), structural formula (viii-1.1) or structural formulae (viii-2.1) to (viii-2.4) can be synthesized by using known synthesis methods. (Liquid crystal composition) The liquid crystal composition according to the present invention can be produced, for example, by mixing the compounds represented by the above general formulas (i) to (iii) and, if necessary, the above other compounds and additives.

[0355] Examples of the additives include a stabilizer, a chiral agent, an antistatic agent, a polymerizable compound, and a dichroic dye.

[0356] Examples of the stabilizer include hydroquinones, hydroquinone monoalkyl ethers, tert-butylcatechols, pyrogallols, thiophenols, nitro compounds, β-naphthylamines, β-naphthols, nitroso compounds, hindered phenols, and hindered amines.

[0357] When stabilizers are used, the total content of the stabilizers in 100% by mass of the liquid crystal composition is preferably 0.005 to 1% by mass, more preferably 0.02 to 0.5% by mass, and even more preferably 0.03 to 0.1% by mass.

[0358] Liquid crystal phase upper limit temperature (T NI ) is the temperature at which the liquid crystal composition undergoes phase transition from a nematic phase to an isotropic phase.

[0359] The upper limit temperature of the liquid crystal phase of the liquid crystal composition according to the present invention (T NI ) is T NI The higher the temperature, the more the nematic phase can be maintained even at high temperatures. From the viewpoint of being able to take a wide operating temperature range, the temperature is preferably 95°C or higher, more preferably 100 to 120°C, and even more preferably 100 to 115°C.

[0360] Liquid crystal phase lower limit temperature (T →N ) is the temperature at which a liquid crystal composition undergoes a phase transition from another phase (glass, smectic phase, crystalline phase) to the nematic phase.

[0361] The liquid crystal phase lower limit temperature (T →N ) is T →N The lower the temperature, the more the nematic phase can be maintained even at low temperatures. From the viewpoint of widening the operating temperature range, the temperature is preferably -15°C or lower, more preferably -78 to -20°C, and even more preferably -50 to -25°C.

[0362] The refractive index anisotropy (Δn) of the liquid crystal composition according to the present invention at 25° C. and 589 nm is preferably 0.15 or more, preferably 0.15 to 0.40, preferably 0.20 to 0.35, and more preferably 0.22 to 0.30.

[0363] Here, the relationship between the retardation Re, the thickness d (cell gap) of the liquid crystal layer, and Δn is expressed by the formula: Δn=Re / d. In this specification, Δn is determined using a retardation measuring device.

[0364] More specifically, a sample of the liquid crystal composition of the present invention is injected into a glass cell with a polyimide alignment film, and the in-plane retardation (phase difference Re) at a measurement temperature of 25°C and 589 nm is measured using a phase difference film / optical material inspection device RETS-100 (manufactured by Otsuka Electronics Co., Ltd.).

[0365] The glass cell used has a cell gap of 3.0 μm between the glass substrates and a parallel rubbing direction of the polyimide alignment film.

[0366] Alternatively, ne and no of the liquid crystal composition may be measured using an Abbe refractometer, and Δn may be calculated.

[0367] The threshold voltage (Vth) of the liquid crystal composition according to the present invention at 25° C. is preferably 2.5 V or less, more preferably 2.4 V or less, and even more preferably 2.35 V or less.

[0368] Vth indicates the minimum voltage at which liquid crystal is driven. A liquid crystal composition with a low Vth allows the liquid crystal to be driven even at a low voltage, and therefore the driving voltage of the liquid crystal display element can be reduced. (Liquid crystal display elements, sensors, liquid crystal lenses, optical communication devices) A liquid crystal display element, a sensor, a liquid crystal lens, and an optical communication device using the liquid crystal composition according to the present invention will be described below.

[0369] The liquid crystal display element according to the present invention is characterized by using the above-mentioned liquid crystal composition, and is preferably driven by an active matrix system or a passive matrix system.

[0370] It can also be used as a liquid crystal display element that can switch between 2D and 3D.

[0371] The liquid crystal display element according to the present invention is preferably a liquid crystal display element in which the dielectric constant is reversibly switched by reversibly changing the alignment direction of the liquid crystal molecules of the above-mentioned liquid crystal composition.

[0372] The sensor according to the present invention is characterized by using the above-mentioned liquid crystal composition, and examples of its embodiments include a distance measuring sensor that uses electromagnetic waves, visible light or infrared light, an infrared sensor that uses a change in temperature, a temperature sensor that uses a change in the wavelength of reflected light due to a change in the pitch of a cholesteric liquid crystal, a pressure sensor that uses a change in the wavelength of reflected light, an ultraviolet sensor that uses a change in the wavelength of reflected light due to a change in composition, an electrical sensor that uses a change in temperature due to a voltage or current, a radiation sensor that uses a temperature change accompanying the track of a radiation particle, an ultrasonic sensor that uses a change in the arrangement of liquid crystal molecules due to mechanical vibration of ultrasonic waves, and an electromagnetic field sensor that uses a change in the wavelength of reflected light due to a change in temperature or a change in the arrangement of liquid crystal molecules due to an electric field.

[0373] The distance measurement sensor is preferably for use in LiDAR (Light Detection And Ranging) that uses a light source.

[0374] As the LiDAR, preferred applications include artificial satellites, aircraft, unmanned aerial vehicles (drones), automobiles, railways, and ships.

[0375] For automobiles, self-driving automobiles are particularly preferred.

[0376] The light source is preferably an LED or a laser, preferably a laser.

[0377] The light used in LiDAR is preferably infrared light, and the wavelength is preferably 800 to 2000 nm.

[0378] In particular, an infrared laser with a wavelength of 905 nm or 1550 nm is preferred.

[0379] When the cost of the photodetector to be used and sensitivity in all weather conditions are important, a 905 nm infrared laser is preferred, whereas when safety regarding human vision is important, a 1550 nm infrared laser is preferred.

[0380] The liquid crystal composition according to the present invention exhibits a high Δn value, and therefore has a large phase modulation power in the visible light, infrared light and electromagnetic wave regions, and can provide a sensor with excellent detection sensitivity.

[0381] The liquid crystal lens of the present invention is characterized by using the above-mentioned liquid crystal composition, and for example, in one embodiment thereof, has a first transparent electrode layer, a second transparent electrode layer, a liquid crystal layer containing the above-mentioned liquid crystal composition provided between the first transparent electrode layer and the second transparent electrode layer, an insulating layer provided between the second transparent electrode layer and the liquid crystal layer, and a high-resistance layer provided between the insulating layer and the liquid crystal layer.

[0382] The liquid crystal lens according to the present invention is used, for example, as a 2D / 3D switching lens, a lens for adjusting the focus of a camera, and the like.

[0383] The optical communication device according to the present invention is characterized by using the above-mentioned liquid crystal composition, and one of its embodiments is, for example, LCOS (Liquid crystal on silicon) having a liquid crystal layer in which liquid crystals constituting each of a plurality of pixels are arranged two-dimensionally on a reflective layer (electrode).

[0384] The optical communication device according to the present invention is used, for example, as a spatial phase modulator. EXAMPLES

[0385] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples in any way.

[0386] The compositions of the following Examples and Comparative Examples contained each compound in the proportions shown in the table, and the contents are shown in "mass %".

[0387] The compounds are described using the following abbreviations. Compounds that can be in either cis or trans form are represented as trans forms unless otherwise specified.

[0388] <Ring structure>

[0389] [ka]

[0390] <Terminal structure>

[0391] [Table 1]

[0392] (However, n in the table is a natural number.) <Connection structure>

[0393] [Table 2]

[0394] <Physical properties> T NI (°C): The temperature at which the liquid crystal composition transitions from a nematic phase to an isotropic phase (upper limit temperature) T →N (°C): The temperature at which the liquid crystal composition transitions from another phase to a nematic phase (lower limit temperature) Δn: refractive index anisotropy of the liquid crystal composition at 25° C. and 589 nm V th : Threshold voltage of liquid crystal composition measured at 25°C using 8.3 μm gap TN cell (Examples 1 to 5 and Comparative Examples 1 to 3) Liquid crystal compositions of Examples 1 to 5 and Comparative Examples 1 to 3 were prepared and their physical properties were measured. The results are shown in Tables 3 and 4.

[0395] [Table 3]

[0396] [Table 4]

[0397] From Example 1 and Comparative Examples 1 to 3, it was found that the liquid crystal composition using one or more of the three specified compounds in combination has a large refractive index anisotropy (Δn) and a liquid crystal phase upper limit temperature (T NI ), liquid crystal phase lower limit temperature (T →N ) and threshold voltage (Vth) were good, but the liquid crystal compositions that did not use one or more of the three specified compounds in combination had a low liquid crystal phase upper limit temperature (T NI ) is low, less than 95°C, or the liquid crystal phase lower limit temperature (T →N ) was above -15℃, resulting in poor results.

[0398] Moreover, from Examples 2 to 5, it was confirmed that the same effect was obtained even when various compounds were used in combination. [Industrial Applicability]

[0399] The liquid crystal composition of the present invention can be used in liquid crystal display devices, sensors, liquid crystal lenses and optical communication devices.

Claims

1. The following structural formulas (i-1.1) and (i-1.2) 【Chemistry 1】 A compound represented by the formula: The following structural formulas (ii.2) and (ii.5): 【Chemistry 2】 and a compound represented by the formula: The following structural formulas (iii-1.2) and (iii-2.1): 【Chemistry 3】 and a compound represented by the formula: The following structural formula (iv.1): 【Chemistry 4】 and a compound represented by the formula: The following structural formulas (vi-2.1) and (vi-2.2): 【Chemistry 5】 and a compound represented by the formula: The following structural formulas (vii.1), (vii.2), (vii.3), (vii.4), and (vii.5): 【Chemistry 6】 A compound represented by the formula: The following structural formulas (v-2.1) and (v-2.2) 【Chemistry 7】 and a compound represented by the formula: The following structural formula (v-4.1): 【Chemistry 8】 and a compound represented by The contents of the compounds represented by the structural formulas (i-1.1) and (i-1.2) are 5% by mass and 5% by mass, respectively, based on the total amount of the composition; The contents of the compounds represented by the structural formulas (ii.2) and (ii.5) are 6% by mass and 6% by mass, respectively, based on the total amount of the composition; The contents of the compounds represented by the structural formulas (iii-1.2) and (iii-2.1) are 8% by mass and 8% by mass, respectively, based on the total amount of the composition; The content of the compound represented by the structural formula (iv.1) is 13% by mass based on the total amount of the composition, The contents of the compounds represented by the structural formulas (v-2.1) and (v-2.2) are 3% by mass and 3% by mass, respectively, based on the total amount of the composition; The contents of the compounds represented by the structural formulas (vi-2.1) and (vi-2.2) are 2% by mass and 2% by mass, respectively, based on the total amount of the composition; the contents of the compounds represented by the structural formulas (vii.1), (vii.2), (vii.3), (vii.4), and (vii.5) are 9% by mass, 9% by mass, 5% by mass, 6% by mass, and 6% by mass, respectively, relative to the total amount of the composition; A liquid crystal composition, wherein the content of the compound represented by the structural formula (v-4.1) is 4% by mass relative to the total amount of the composition.

2. 2. The liquid crystal composition according to claim 1, which has a refractive index anisotropy (.DELTA.n) of 0.15 or more at 25.degree. C. and 589 nm.

3. A liquid crystal display device using the liquid crystal composition according to claim 1 or 2.

4. A sensor using the liquid crystal composition according to claim 1 or 2.

5. A liquid crystal lens using the liquid crystal composition according to claim 1 or 2.

6. 3. An optical communication device using the liquid crystal composition according to claim 1.

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