JP2013170248A - Nematic liquid crystal composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal composition with positive dielectric constant anisotropy, sufficiently low in viscosity (η) and giving no defective display, without lowering or raising its own refractive index anisotropy (Δn) and nematic phase-isotropic liquid phase transition temperature (Tni).SOLUTION: A liquid crystal composition with positive dielectric constant anisotropy comprises: one or two or more compounds selected from those represented by general formula (LC1) or the like (wherein, Ris alkyl; Ato Ais a (fluorine or the like-substituted) cyclohexane ring or phenylene ring; Yis F or the like; and Zand Zare each a linkage group such as a single bond); and several compounds each having cyclohexane ring(s) and/or benzene ring(s).

Description

  The present invention relates to a nematic liquid crystal composition having a positive dielectric anisotropy (Δε) useful as an electro-optical liquid crystal display material.

  Liquid crystal display elements are used in various measuring instruments, automobile panels, word processors, electronic notebooks, printers, computers, televisions, watches, advertisement display boards, as well as watches and calculators. Typical liquid crystal display methods include TN (twisted nematic) type, STN (super twisted nematic) type, vertical alignment type using TFT (thin film transistor), and IPS (in-plane switching) type. Etc. The liquid crystal composition used in these liquid crystal display elements is stable against external factors such as moisture, air, heat, light, etc., and exhibits a liquid crystal phase in the widest possible temperature range centering on room temperature, and has low viscosity. And a low driving voltage is required. Furthermore, the liquid crystal composition has several to several tens of kinds of compounds in order to optimize the dielectric anisotropy (Δε) and the refractive index anisotropy (Δn) for each display element. It is composed of

A liquid crystal composition having a negative Δε is used for a vertical alignment type display, and a liquid crystal composition having a positive Δε is used for a horizontal alignment type display such as a TN type, STN type, or IPS type. In addition, a driving method has been reported in which a liquid crystal composition having a positive Δε is vertically aligned when no voltage is applied and a horizontal electric field is applied to display the liquid crystal composition, and the necessity of a liquid crystal composition having a positive Δε is further increased. Yes. On the other hand, low voltage driving, high-speed response, and a wide operating temperature range are required in all driving systems. That is, Δε is positive, the absolute value is large, the viscosity (η) is small, and a high nematic phase-isotropic liquid phase transition temperature (T _ni ) is required. Further, from the setting of Δn × d, which is the product of Δn and the cell gap (d), it is necessary to adjust Δn of the liquid crystal composition to an appropriate range according to the cell gap. In addition, when applying a liquid crystal display element to a television or the like, since high-speed response is important, a liquid crystal composition having a small γ ₁ is required.

  There is a disclosure of a liquid crystal composition using a compound represented by the formula (A-1) or (A-2) which is a liquid crystal compound having a positive Δε as a constituent component of the liquid crystal composition (Patent Documents 1 to 4). These liquid crystal compositions have not yet achieved a sufficiently low viscosity.

WO96 / 032365 JP 09-157202 A WO98 / 023564 JP 2003-183656 A

The problem to be solved by the present invention is that the viscosity (η) is sufficiently low without reducing or increasing the refractive index anisotropy (Δn) and the nematic phase-isotropic liquid phase transition temperature (T _ni ), In addition, another object is to provide a liquid crystal composition having a positive dielectric anisotropy (Δε).

  The present inventor has studied various fluorobenzene derivatives and found that the above problem can be solved by combining specific compounds, and has completed the present invention.

  The present invention is a liquid crystal composition having positive dielectric anisotropy, wherein the liquid crystal composition contains one or more compounds selected from compounds represented by the general formula (LC1), Furthermore, the present invention provides a liquid crystal composition comprising one or more compounds selected from the group of compounds represented by general formula (LC2) and / or general formula (LC3), and further provides the liquid crystal A liquid crystal display device using the composition is provided.

(In the formula, R ¹¹ represents an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are —O—, —CH, so that an oxygen atom is not directly adjacent thereto. ═CH—, —CO—, —OCO—, —COO—, —C≡C—, —CF ₂ O—, —OCF ₂ —, which may be substituted with one or more of the alkyl groups The hydrogen atom may be optionally halogen-substituted, and A ¹¹ , A ¹² and A ¹³ are each independently any one of the following structures

(In the structure, X ¹ and X ² each independently represent H, Cl, F, CF ₃ or OCF _3, and one or more CH ₂ groups in the cyclohexane ring may be substituted with O atoms. Well, one or more CH groups of the benzene ring in the structure may be substituted with N atoms, and one or more H atoms in the structure may be Cl, CF ₃ or OCF . represents that may) be substituted with ^{_3, Y 11} is -Cl independently, -F, represents -CF ₃ or -OCF ^{_3, Z} 11 ^{~Z 12} each independently represent a single bond, - CH = CH—, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —OCF ₂ — or —CF ₂ O—, each of m ¹¹ and m ¹² is independently 0 Table 1, 2, 3 or 4 represent to 3 ^{integers, m} 11 ⁺ m ¹² each independently If ^{the A 11, A 13, Z} 11 and / or ^{Z 12} is plurally present, they may be the same or different. X ¹¹ and X ¹² each independently represent —H, —Cl, —F, —CF ₃ or —OCF ₃ , and Y ¹¹ independently represents —Cl, —F, —CF ₃ or —OCF ₃ , Z ¹¹ and Z ¹² are each independently a single bond, —CH═CH—, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —OCF ₂ — Or -CF ₂ O-, m ¹¹ and m ¹² each independently represents an integer of 0 to 2, m ¹¹ + m ¹² each independently represents 0, 1, 2 or 3, and A ¹¹ , A ^{When a} plurality of ¹³ , Z ¹¹ and / or Z ¹² are present, they may be the same or different. )

(In the formula, R ²¹ and R ³¹ represent an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are —O— so that the oxygen atom is not directly adjacent to each other. , —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—, —OCF ₂ —, —CF ₂ O—, one or two of the alkyl groups Two or more hydrogen atoms may be optionally halogen-substituted, and A ²¹ , A ²² , A ²³ , A ³¹ , A ³² , and A ³³ are each independently any one of the following structures:

(In the structure, X ³ and X ⁴ each independently represent H, Cl, F, CF ₃ or OCF _3, and one or more CH ₂ groups of the cyclohexane ring may be substituted with oxygen atoms. In the structure, one or more CH groups of the benzene ring may be substituted with a nitrogen atom, and one or more hydrogen atoms in the structure may be Cl, CF ₃ or OCF. ₃ may be substituted.) ^represent, X 21 ^{to X 32} each independently -H, -Cl, -F, represents -CF ₃ or -OCF ^{_3, Y 21} and ^{Y 31} are each independently to -Cl, -F, represents -CF ₃ or -OCF ^{_3, Z} 21 ^{~Z 32} each independently represent a single bond, -CH = CH -, - C≡C -, - CH 2 CH 2 -, _{- (CH 2) 4 -,} - OCF 2 - or _-CF 2 O-a ^{represents, m 21} m ³² represents an integer of independently ^{0~3, m} 21 ⁺ m ^22, and ^m 31 ^{+ m 32} each independently represents 0, 1, 2, 3 or ^{4, A 21, A 23,} A 31 , A ³³ , Z ²¹ , Z ²² , Z ³¹ and / or Z ³² , they may be the same or different. )

The liquid crystal composition of the present invention is characterized in that Δε is positive and its absolute value is large. Also, η is low, rotational viscosity (γ ₁ ) is small, liquid crystallinity is excellent, and a stable liquid crystal phase is exhibited over a wide temperature range. Further, it is a practical and reliable liquid crystal composition that is chemically stable to heat, light, water, and the like and can be driven at a low voltage.

  The liquid crystal composition in the present invention contains one or more compounds selected from the compound represented by the general formula (LC1), and is further represented by the general formula (LC2) and / or the general formula (LC3). 1 type, or 2 or more types of compounds chosen from the compound group which contains. A liquid crystal composition containing the compound represented by the general formula (LC1) and the compound represented by the general formula (LC2) and / or the general formula (LC3) exhibits a stable liquid crystal phase even at a low temperature. It can be said that it is a composition.

In these general formulas (LC1) to (LC3), R ^{11 to} R ³¹ each independently represents an alkyl group having 1 to 15 carbon atoms, and one or more CH ₂ in the alkyl group. The groups are selected from —O—, —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—, —CF ₂ O—, —OCF ₂ — so that the oxygen atom is not directly adjacent. 1 or 2 or more hydrogen atoms in the alkyl group may be optionally halogen-substituted, but an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, or An alkoxy group having 1 to 8 carbon atoms is preferable, and a straight chain is preferable.
A ¹¹ , A ¹² and A ¹³ are each independently a trans-1,4-cyclohexylene group, 1,4-phenylene group, 3-fluoro-1,4-phenylene group or 3,5-difluoro-1, A 4-phenylene group is preferred.
A ²¹ , A ²² , A ²³ , A ³¹ , A ³² , and A ³³ are each independently a trans-1,4-cyclohexylene group, 1,4-phenylene group, 3-fluoro-1,4-phenylene group Or a 3,5-difluoro-1,4-phenylene group is preferable.
X ¹ , X ² , X ³ and X ⁴ are each independently preferably H or F. X ^{21 to} X ³² are each independently preferably H or F, and X ²¹ and X ³¹ are more preferably F.

Y ^{11 to} Y ³¹ are each independently preferably F, CF ₃ or OCF ₃ , and more preferably F or OCF ₃ .
Z ¹¹ and Z ¹² are each independently preferably a single bond, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —OCF ₂ — or —CF ₂ O—, ^{When one of 11} and Z ¹² represents —CH═CH—, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —OCF ₂ — or —CF ₂ O— Preferably represents a single bond, more preferably all represent a single bond.
Z ^{21 to} Z ³² are each independently preferably a single bond, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —OCF ₂ — or —CF ₂ O—. one is -CH = CH of _{^{21 ~Z 32 -, - C≡C -}} , - CH 2 CH 2 -, - (CH 2) 4 -, - OCF 2 - or if the representative of the _-CF 2 O-, other Preferably represents a single bond, more preferably all represent a single bond.
m ^{11 to} m ³¹ each independently preferably represents an integer of 0 to 2, and m ¹¹ + m ¹² , m ²¹ + m ²² and m ³¹ + m ³² are each independently preferably 1, 2 or 3.

  The liquid crystal compounds represented by the general formula (LC1) are represented by the following general formulas (LC1-1) to (LC1-4).

(Wherein, R ¹¹ , A ¹² , A ¹³ , Z ¹² and Y ¹¹ represent the same meaning as in the general formula (LC1)), and are more preferable. From the following general formula (LC1-1-1) to general formula (LC1-4-18)

(Wherein R ¹¹ represents the same meaning as in formula (LC1)), and is more preferable.

  Compounds represented by general formula (LC2) are represented by the following general formula (LC2-1) to general formula (LC2-5).

(Wherein R ²¹ , A ²¹ , A ²² , A ²³ , Z ²¹ , Z ²² , X ²¹ , X ²² and Y ²¹ represent the same meaning as in formula (LC2), and A ²¹ , A ²³ , Z ²¹ and Z ²² it is preferred if present twice each is a compound represented by each may be the same or different.). From the following general formula (LC2-1-1) to general formula (LC2-5-9)

(Wherein R ²¹ , X ³ , X ⁴ and Y ²¹ represent the same meaning as in formula (LC2)), and more preferably a compound represented by

  Compounds represented by general formula (LC3) are represented by the following general formula (LC3-1) to general formula (LC3-5).

(Wherein R ³¹ , A ³¹ , A ³² , A ³³ , Z ³¹ , Z ³² , X ³¹ , X ³² and Y ³¹ represent the same meaning as in general formula (LC3), and A ³¹ , A ³³ , Z ^When two each of ³¹ and Z ³² are present, they may be the same or different. From the following general formula (LC3-1-1) to general formula (LC3-5-9)

(Wherein, R ³¹ , X ³ , X ⁴ , X ³² and Y ³¹ represent the same meaning as in general formula (LC3)), and more preferably.

  In addition, the liquid crystal composition of the present invention may contain other compounds in order to adjust the physical properties and viscosity of the liquid crystal composition, but from the following general formulas (LC4-1) to (LC4-14) It is preferable to contain the compound represented by this.

(In the formula, R ⁴¹ and R ⁴² represent an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are —O— so that the oxygen atom is not directly adjacent to each other. , —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—, —OCF ₂ —, —CF ₂ O—, one or two of the alkyl groups (One or more hydrogen atoms may be optionally substituted with halogen.)
In addition, the liquid crystal composition of the present invention may contain a polymerizable compound in order to produce a liquid crystal display element such as a polymer stabilization (PS) mode. Examples of the polymerizable compound that can be used include a photopolymerizable monomer that undergoes polymerization by energy rays such as light. The structure has a liquid crystal skeleton in which a plurality of six-membered rings such as biphenyl derivatives and terphenyl derivatives are connected. Examples thereof include a polymerizable compound. Specifically, the polymerizable compound is represented by the general formula (PC1).

(Wherein P ₁ represents a polymerizable functional group, Sp ₁ represents a spacer group having 0 to 20 carbon atoms, and Q ₁ represents a single bond, —O—, —NH—, —NHCOO—, —OCONH— , -CH = CH-, -CO-, -COO-, -OCO-, -OCOO-, -OOCO-, -CH = CH-, -CH = CH-COO-, -OCO-CH = CH- or- C≡C—, n ₁ and n ₂ each independently represent 1, 2 or 3, MG represents a mesogenic group or mesogenic support group, and R ₃ represents a halogen atom, a cyano group or the number of carbon atoms 1 to 25 alkyl groups, and one or more CH ₂ groups in the alkyl group are —O—, —S—, —NH—, —N (, so that the O atom is not directly adjacent. _{CH 3) -, - CO -} , - COO -, - OCO -, - OCOO -, - SCO -, - CO - or -C≡C- may have more replaced, or _{R 3} is _{P 2 -Sp 2 -Q 2 - (} P 1 and _{wherein, P 2, Sp 2, Q} 2 are each independently, Sp ₁ , Which represents the same meaning as Q ₁ ), and a polymerizable compound represented by

  More preferably, MG in the polymerizable compound general formula (PC1) has the following structure:

(Wherein C _{1 to} C ₃ are each independently 1,4-phenylene group, 1,4-cyclohexylene group, 1,4-cyclohexenyl group, tetrahydropyran-2,5-diyl group, 1,3 -Dioxane-2,5-diyl group, tetrahydrothiopyran-2,5-diyl group, 1,4-bicyclo (2,2,2) octylene group, decahydronaphthalene-2,6-diyl group, pyridine-2 , 5-diyl group, pyrimidine-2,5-diyl group, pyrazine-2,5-diyl group, 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 2,6-naphthylene group, phenanthrene -2,7-diyl group, 9,10-dihydrophenanthrene-2,7-diyl group, 1,2,3,4,4a, 9,10a-octahydrophenanthrene 2,7-diyl group or fluorene 2,7 -Diyl group, the 1,4-phenylene group, 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 2,6-naphthylene group, phenanthrene-2,7-diyl group, 9, 10-dihydrophenanthrene-2,7-diyl group 1,2,3,4,4a, 9,10a- octahydrophenanthrene 2,7-diyl group and fluorene 2,7-diyl group is 1 or more F as _{substituents, Cl, CF 3, OCF 3} , cyano Group, an alkyl group having 1 to 8 carbon atoms, an alkoxy group, an alkanoyl group, an alkanoyloxy group, an alkenyl group having 2 to 8 carbon atoms, an alkenyloxy group, an alkenoyl group or an alkenoyloxy group. , Y ₁ and Y ₂ are each independently —COO—, —OCO—, —CH ₂ CH ₂ —, —OCH ₂ —, —CH ₂ O—, —CH═CH—, —C≡C—, — _{CH = CHCOO -, - OCOCH =} CH -, - CH 2 CH 2 COO -, - CH 2 CH 2 OCO -, - COOCH 2 CH 2 -, - OCOCH 2 CH 2 -, - CONH -, - NHCO- or single It represents a bond, _{n 5} is A polymerizable compound represented by representative.) 1 or 2,
Sp ₁ and Sp ₂ each independently represent an alkylene group, which may be substituted by one or more halogen atoms or CN, and one or more CH ₂ present in this group. The groups are —O—, —S—, —NH—, —N (CH ₃ ) —, —CO—, —COO—, —OCO—, —OCOO—, —SCO—, so that the O atom is not directly adjacent. -COS- or -C≡C- may be substituted,
P ₁ and P ₂ are each independently the following general formula (PC1-a) to general formula (PC1-d)

(Wherein R ^{51 to} R ⁵³ , R ^{61 to} R ⁶³ , and R ^{71 to} R ⁷³ each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms). expressed.

  More specifically, the polymerizable compound general formula (PC1) is represented by the general formula (PC1) -1 or the general formula (PC1) -2.

(In the formula, P ₁ , Sp ₁ , Q ₁ , P ₂ , Sp ₂ , Q ₂ and MG represent the same meaning as in the general formula (PC1), and n ₃ and n ₄ are independently 1, 2 or 3 respectively. It is preferable that it is a polymeric compound represented by this.

  More specifically, the general formula (PC1) is represented by the general formula (PC1) -3 to the general formula (PC1) -8.

Wherein W ₁ is independently F, CF ₃ , OCF ₃ , CH ₃ , OCH ₃ , an alkyl group having 2 to 5 carbon atoms, an alkoxy group, an alkenyl group, COOW ₂ , OCOW ₂ or OCOW ₂ . (Wherein W ₂ represents a linear or branched alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and n ₃ , n ₄ and n ₆ are each independently 0, It is more preferably a polymerizable compound represented by 1, 2, 3, or 4.

Further, Sp ₁ , Sp ₂ , Q ₁ and Q ₂ in General Formula (PC1) -3 to General Formula (PC1) -8 are all single bonds, and in n ₃ and n ₄ , n ₃ + n ₄ is 3 a to 6, _{P 1} and _{P 2} are formula (PC1-c), _{W 1} is _F, a CF _{3, OCF} 3, CH 3 or OCH _3, is preferably _{n 6} is 1 or more .

  Moreover, it is also preferable that MG in the general formula (PC1) is a discotic liquid crystal compound represented by the general formula (PC1) -9.

(In the formula, each R ⁷ is independently P ₁ -Sp ₁ -Q ₁ or the general formula (PC1-e)

(Wherein P ₁ , Sp ₁ and Q ₁ represent the same meaning as in general formula (PC1), R ⁸¹ and R ⁸² each independently represent a hydrogen atom, a halogen atom or a methyl group, and R ⁸³ represents a carbon atom. Represents an alkoxy group of formula 1 to 20, and at least one hydrogen atom in the alkoxy group may be substituted with a substituent represented by the general formulas (PC1-a) to (PC1-d). Represents a substituent of )
The amount of the polymerizable compound used is preferably 0.1 to 2.0% by mass.

Furthermore, the liquid crystal composition of the present invention can contain one or more antioxidants in order to improve the stability, and can also contain one or more UV absorbers.
The liquid crystal display device using the liquid crystal composition of the present invention is useful for achieving both high-speed response and suppression of display failure, and is particularly useful for a liquid crystal display device for active matrix driving, including TN mode, OCB mode, It can be applied to a liquid crystal display element for IPS mode, FFS mode or VA-IPS mode.
By using the liquid crystal composition of the present invention containing the polymerizable compound described above, a polymer stabilized (PS) mode liquid crystal display element can be produced. Specifically, a liquid crystal composition containing a polymerizable compound is sandwiched between two substrates, and the polymerizable compound in the liquid crystal composition is polymerized by energy such as ultraviolet rays with or without voltage applied. Can be produced. In this liquid crystal display element, the orientation state of the liquid crystal molecules can be memorized by polymerizing the polymerizable compound, whereby the stability of the orientation state can be improved. In addition, an improvement in response speed can be expected.

  Hereinafter, although an example is given and this invention is further explained in full detail, this invention is not limited by these. Further, “%” in the compositions of the following examples and comparative examples means “mass%”.

The physical properties of the liquid crystal composition are expressed as follows.
T _NI : Nematic phase-isotropic liquid phase transition temperature (° C)
Tn: lower limit temperature of nematic phase (° C)
ε⊥: dielectric constant in the direction perpendicular to the molecular long axis direction at 25 ° C. Δε: dielectric anisotropy at 25 ° C. no: refractive index for ordinary light at 25 ° C. Δn: refractive index anisotropic at 25 ° C. sex
Vth: Applied voltage (V) in a cell having a cell thickness of 6 μm in which the transmittance changes by 10% when a rectangular wave with a frequency of 1 KHz is applied at 25 ° C.
η ₂₀ : Bulk viscosity at 20 ° C. (mPa · s)
γ ₁ : rotational viscosity (mPa · s)
The following abbreviations are used in compound descriptions.

Example 1
The prepared liquid crystal composition and its physical property values are shown below.

(Comparative Example 1)
The prepared liquid crystal composition and its physical property values are shown below.

The liquid crystal composition is a liquid crystal composition not containing the compound represented by the general formula (LC1) of the present application. Example 2 has a much lower viscosity and smaller γ ₁ , indicating that the combination of the present invention is very excellent (Example 2).
The prepared liquid crystal composition and its physical property values are shown below.

(Example 3)
The prepared liquid crystal composition and its physical property values are shown below.

Example 4
The prepared liquid crystal composition and its physical property values are shown below.

(Example 5)
The prepared liquid crystal composition and its physical property values are shown below.

(Example 6)
The prepared liquid crystal composition and its physical property values are shown below.

(Example 7)
The prepared liquid crystal composition and its physical property values are shown below.

(Example 8)
The prepared liquid crystal composition and its physical property values are shown below.

Example 9
The prepared liquid crystal composition and its physical property values are shown below.

Thus, it can be seen that the liquid crystal compositions of Examples 2 to 9 have a low viscosity, γ ₁ is small, and the combination of the present invention is very excellent.
(Example 10)
Using a first substrate in which a pair of transparent electrodes having a comb-shaped electrode structure is provided on the same substrate and a second substrate not having an electrode structure, a vertical alignment film is formed on each substrate, and the first substrate and An IPS empty cell having a gap interval of 4.0 microns was fabricated on the second substrate. The liquid crystal composition shown in Example 3 was injected into this empty cell to produce a liquid crystal display element. When the electro-optical characteristics of this display element were measured, the applied voltage at which the transmittance changed by 10% was 1.63 v. The response speed when 5v was applied was 4.4 milliseconds, and the response speed when the voltage was turned off was 12.3 seconds.
The polymerizable compound represented by the formula (PC-1) -3-1 with respect to 99% of the liquid crystal composition shown in Example 3

1% was added and uniformly dissolved to prepare a polymerizable liquid crystal composition CLC-A. The physical properties of CLC-A were almost the same as those of the liquid crystal composition shown in Example 3.
After CLC-A is sandwiched between the above IPS empty cells, UV light is irradiated to the liquid crystal cell by a high-pressure mercury lamp through a filter that cuts UV light of 300 nm or less while applying a rectangular wave of 1.8 V at a frequency of 1 KHz. did. The cell surface was adjusted to have an irradiation intensity of 20 mW / cm ² and irradiated for 600 seconds to obtain a vertically aligned liquid crystal display element in which the polymerizable compound in the polymerizable liquid crystal composition was polymerized. When the electro-optical characteristics of this display element were measured, the applied voltage at which the transmittance changed by 10% was 1.86 v. The response speed when 5v was applied was 4.4 milliseconds. In addition, the response speed when the voltage was turned off was 4.3 milliseconds, which was very fast compared to the liquid crystal display device manufactured using only the liquid crystal composition shown in Example 3.

Claims (9)

A liquid crystal composition having positive dielectric anisotropy, wherein the liquid crystal composition contains one or more compounds selected from the compounds represented by formula (LC1);

(In the formula, R ¹¹ represents an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are —O—, —CH, so that an oxygen atom is not directly adjacent thereto. ═CH—, —CO—, —OCO—, —COO—, —C≡C—, —CF ₂ O—, —OCF ₂ —, which may be substituted with one or more of the alkyl groups The hydrogen atom may be optionally halogen-substituted, and A ¹¹ , A ¹² and A ¹³ are each independently any one of the following structures

(In the structure, X ¹ and X ² each independently represent H, Cl, F, CF ₃ or OCF _3, and one or more CH ₂ groups in the cyclohexane ring may be substituted with O atoms. Well, one or more CH groups of the benzene ring in the structure may be substituted with N atoms, and one or more H atoms in the structure may be Cl, CF ₃ or OCF . represents that may) be substituted with ^{_3, Y 11} is -Cl independently, -F, represents -CF ₃ or -OCF ^{_3, Z} 11 ^{~Z 12} each independently represent a single bond, - CH = CH—, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —OCF ₂ — or —CF ₂ O—, each of m ¹¹ and m ¹² is independently 0 Table 1, 2, 3 or 4 represent to 3 ^{integers, m} 11 ⁺ m ¹² each independently If ^{the A 11, A 13, Z} 11 and / or ^{Z 12} is plurally present, they may be the same or different. ) The liquid crystal composition further comprises one or more compounds selected from the group of compounds represented by formula (LC2) and / or formula (LC3).

(In the formula, R ²¹ and R ³¹ represent an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are —O— so that the oxygen atom is not directly adjacent to each other. , —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—, —OCF ₂ —, —CF ₂ O—, one or two of the alkyl groups Two or more hydrogen atoms may be optionally halogen-substituted, and A ²¹ , A ²² , A ²³ , A ³¹ , A ³² , and A ³³ are each independently any one of the following structures:

(In the structure, X ³ and X ⁴ each independently represent H, Cl, F, CF ₃ or OCF _3, and one or more CH ₂ groups of the cyclohexane ring may be substituted with oxygen atoms. In the structure, one or more CH groups of the benzene ring may be substituted with a nitrogen atom, and one or more hydrogen atoms in the structure may be Cl, CF ₃ or OCF. ₃ may be substituted.) ^represent, X 21 ^{to X 32} each independently -H, -Cl, -F, represents -CF ₃ or -OCF ^{_3, Y 21} and ^{Y 31} are each independently to -Cl, -F, represents -CF ₃ or -OCF ^{_3, Z} 21 ^{~Z 32} each independently represent a single bond, -CH = CH -, - C≡C -, - CH 2 CH 2 -, _{- (CH 2) 4 -,} - OCF 2 - or _-CF 2 O-a ^{represents, m 21} m ³² represents an integer of independently ^{0~3, m} 21 ⁺ m ^22, and ^m 31 ^{+ m 32} each independently represents 0, 1, 2, 3 or ^{4, A 21, A 23,} A 31 , A ³³ , Z ²¹ , Z ²² , Z ³¹ and / or Z ³² , they may be the same or different. ) 1 type or 2 types or more compound chosen from the compound represented by general formula (LC1), 1 type chosen from the compound group represented by general formula (LC2) and / or general formula (LC3) or 2. A compound containing two or more compounds and further containing one or more compounds selected from the group consisting of compounds represented by formulas (LC4-1) to (LC4-14). The liquid crystal composition described in 1.

(In the formula, R ⁴¹ and R ⁴² represent an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are —O— so that the oxygen atom is not directly adjacent to each other. , —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—, —OCF ₂ —, —CF ₂ O—, one or two of the alkyl groups (One or more hydrogen atoms may be optionally substituted with halogen.) The liquid crystal composition according to any one of claims 1 to 2, comprising one or more polymerizable compounds. The liquid crystal composition according to any one of claims 1 to 3, comprising one or more antioxidants. The liquid crystal composition according to any one of claims 1 to 4, comprising one or more UV absorbers. The liquid crystal display element using the liquid-crystal composition as described in any one of Claim 1 to 5. A liquid crystal display element for driving an active matrix using the liquid crystal composition according to claim 1. A TN mode, OCB mode, IPS mode, FFS mode or VA-IPS mode liquid crystal display element using the liquid crystal composition according to claim 1. A polymer-stabilized mode liquid crystal display device produced by using the liquid crystal composition according to claim 3 and polymerizing a polymerizable compound contained in the liquid crystal composition with or without voltage application.