JP2001011456A - Nematic liquid crystal composition and liquid crystal display device using the composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nematic liquid crystal composition having a wide operational temperature range, an excellent responsiveness and a good contrast against a desirable birefringence, and a liquid crystal display device such as TN-LCD, STN-LCD, TFT-LCD, etc., having improved electrical optical properties. SOLUTION: A nematic liquid crystal composition contains a liquid crystal component A comprising a compound of the formula (wherein R11 is a 2-10C linear alkyl group or the like; R12 is H or 1-5C linear alkyl group; A11 is a cyclohexane ring or the like; and Z11 is a single bond or -C≡C-, provided that when A11 is a cyclohexane ring, Z11 is -C≡C-) and a liquid crystal component B comprising a compound having a dielectric constant anisotropy of +2 or larger. Here, the liquid crystal material has a dielectric constant anisotropy of +3 or larger, a nematic phase/isotropic liquid phase transition temperature of 60 deg.C or higher and a crystal- or smectic phase/nematic phase transition temperature of 0 deg.C or lower.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nematic liquid crystal composition useful as an electro-optical display material and a liquid crystal display using the same.

[0002]

2. Description of the Related Art A typical liquid crystal display element is a TN-LCD.
(Twisted nematic liquid crystal display element)
It is used in watches, calculators, electronic organizers, pocket computers, word processors, personal computers and the like. On the other hand, with the increase in the processing information of the OA equipment, Scheffer et al. [SID '85 Digest, p.120 1985
Year], Kinukawa et al. [SID '86 Digest, p.122 1986], STN (Super Twisted Nematic) -L
CDs have been developed and have begun to spread widely in displays for high information processing such as portable terminals, word processors, and personal computers.

Recently, an active addressing drive system [Proc. 12th IDRC p.5
03 1992] and multi-line addressing drive system [S
ID'92 Digest, p. 232 1992]. As such a liquid crystal material, the elastic constant ratio K ₃₃ / K ₁₁ is around 1.5, and the dielectric constant anisotropy and viscosity are relatively small.
In particular, those having a large birefringence are required. In addition, in order to achieve a brighter display and a higher contrast ratio, a new reflective color liquid crystal display system using the birefringence of liquid crystal and a retardation plate instead of the color filter layer [Television Society Technical Report vol. 14 No10.p.51 1990] and a liquid crystal display device having a reflective surface with a small parabolic surface on the substrate electrode side has been proposed. As a liquid crystal material suitable for this, a birefringence index characteristic that causes a larger phase difference due to a difference in light wavelength and an optical characteristic of a birefringence index that maintains a high contrast even at a wide viewing angle are required. Further, a liquid crystal display device having a wider operating temperature is required for display applications such as miniaturization, portability, and increase in the number of pixels. As a liquid crystal material suitable for this, the elastic constant K ₁₁ is 1
0. ~ 25. There is a demand for a material that is chemically stable, can efficiently reduce the response speed, and has a wider nematic temperature. As described above, there is a need to comprehensively optimize the individual physical properties of the liquid crystal material, and proposals for new liquid crystal compounds or liquid crystal compositions are still required.

Further, due to its excellent display quality, active matrix type liquid crystal display devices have been put on the market for portable terminals, liquid crystal televisions, projectors, computers and the like. In the active matrix display method, a TFT (thin film transistor) or a metal insulator metal (MIM) is used for each pixel, and a high voltage holding ratio is emphasized in this method. In addition, in order to obtain a wider viewing angle characteristic, a super TFT [Asia Display '95 Digest,
p.707 1995] was proposed by Kondo et al.
(Hereinafter, these active matrix display type liquid crystal display elements are collectively referred to as TFT-LCD.) To cope with such display elements, new liquid crystal compounds or liquid crystal compositions such as those disclosed in No. 312949,
A proposal such as Japanese Patent Publication No. 5-501735 has been made.

[0005]

In order to improve the liquid crystal display characteristics as described above, a liquid crystal material having a desired birefringence is required. There is also a need for higher chemical stability of liquid crystal materials, lower viscosity, high-speed response of liquid crystal display, wider characteristics of driving temperature range, and higher contrast. The knowledge of the compound of the general formula (I-1) and a mixture containing this compound according to the present invention has not yet been sufficiently reported. Further, there has not yet been reported a desired liquid crystal material property or mixture in which the desired birefringence, dielectric anisotropy, elastic constant, etc., which are useful for TN-LCD and STN-LCD as described above, are adjusted.

More specifically, as a liquid crystal material having higher chemical stability, lower viscosity, and wider nematic temperature characteristic of the liquid crystal material, for example, the following general formula (a-1):
(A-2)

Embedded image Has been used. However, problems still remain as a liquid crystal material for improving solubility and responsiveness.

An object of the present invention is to solve or further improve the above-mentioned problems. For a desired birefringence, the temperature range in which it can be driven is wide, the response is excellent, and the contrast is high. TN-LCD, ST with improved electro-optical characteristics using this liquid crystal composition as a constituent material
An object of the present invention is to provide a liquid crystal display device such as an N-LCD and a TFT-LCD.

[0008]

The present invention has been made in order to solve the above problems. The liquid crystal composition has the general formula (I-1)

Embedded image (Wherein, R ¹¹ represents a linear alkyl group or alkenyl group having 2 to 10 carbon atoms, and R ¹² represents H or 1 to carbon atoms.
5 represents a linear alkyl group, A ¹¹ represents a cyclohexane ring or a benzene ring or a monofluorinated benzene ring,
Z ¹¹ represents a single bond or —C≡C—. However, when A ¹¹ is a cyclohexane ring, Z ¹¹ is -C≡C-. ), A liquid crystal component A comprising a compound having one or more compounds, and a liquid crystal component B comprising a compound having a dielectric anisotropy of +2 or more, wherein the liquid crystal material has a dielectric constant of 3 or more. A nematic liquid crystal composition, which has anisotropy of a crystal ratio, a nematic phase-isotropic liquid phase transition temperature of 60 ° C. or more, and a crystal phase or a smectic phase-nematic phase transition temperature of 0 ° C. or less. 2. The liquid crystal component A contains 30 to 100% by weight of a compound in which R ¹¹ in the general formula (I-1) is an ethyl group, a propyl group or a butyl group and / or a compound in which R ¹² is H. 2. The nematic liquid crystal composition according to the above item 1, wherein 3. The liquid crystal material contains 1 to 50% by weight of the liquid crystal component A.
3. The nematic liquid crystal composition according to any one of the above items 1 to 2, which is contained. 4. The liquid crystal component B has a general formula (II-1) to (II-4)

Embedded image(Where R^{twenty one}~ R^{twenty four}Are each independently 2 to 10 carbon atoms
Linear alkyl group, alkenyl group or C_sH_{2s + 1}-O
-C_tH_2tAnd s and t are each independently an integer of 1 to 5
Represents a number, X^{twenty one}~ X^{twenty four}Are each independently F, Cl, -OC
F_Three, -OCHF_Two, -CF_ThreeOr -CN.^{twenty one}~ Y
²⁸Each independently represents H or F;^{twenty one}~ W^{Two Four}Is German
Standing for H or F, Z^{twenty one}~ Z^{twenty three}Are independently connected
-COO-, -C_TwoH_Four-Or -C_FourH₈-Represents Z
^{twenty one}May also be -C≡C- or -CH = CH-
, Z^{twenty four}, Z^{twenty five}Are each independently a single bond, -COO-,-
Represents C≡C- or -CF = CF-, m¹~ M^FourIs German
Stands for 0 or 1, and m^Three+ M^FourIs 0 or 1 and each
Hydrogen atom of cyclohexane ring in compound is deuterium source
May be replaced by a child D (hereinafter used in this sense)
No. ) Containing a compound selected from the group of compounds represented by
3. The nematic liquid crystal set according to any one of the above 1 to 3, wherein
Adult. 5. The liquid crystal component B is represented by the general formulas (II-1) to (II-4)
R in^{twenty one}~ R^{twenty four}Is an alkyl group having 2 to 5 carbon atoms or
Is a compound which is an alkenyl group, and / or X^{twenty one}~ X ^{twenty four}But
F, Cl, -OCF_ThreeOr a compound that is -CN from 10 to
100% by weight of the above 4 nemas,
Tic liquid crystal composition. 6. The liquid crystal component B is a compound of the general formula (II-1)
Z^{twenty one}, Z^{twenty two}Is a single bond, -COO-, -C_TwoH_Four-Again
Is -C_FourH₈Containing 10 to 100% by weight of the compound represented by
The nematic liquid according to the above 4 to 5, which has
Crystal composition. 7. The liquid crystal component B is a compound of the general formula (II-2)
Z^{twenty four}Is represented by a single bond, -COO- or -C≡C-
Characterized by containing 10 to 100% by weight of the compound
7. The nematic liquid crystal composition according to the above 4 to 6, wherein 8. The liquid crystal component B is a compound of the general formula (II-3)
Z^{twenty five}Is a single bond or a compound represented by -C≡C-
(4) characterized in that it contains at least 10% by weight.
8. The nematic liquid crystal composition according to any one of items 1 to 7. 9. The liquid crystal material contains the liquid crystal component B in an amount of 10 to 99% by weight.
%.
Liquid crystal composition. 10. The liquid crystal material has a dielectric anisotropy of -2 to 2;
Liquid crystal component C comprising a compound
Has the general formulas (III-1) to (III-4)

Embedded image(Where R³¹~ R³⁴Each independently has 2 to 7 carbon atoms
Represents a linear alkyl group or an alkenyl group,³⁵~ R³⁸
Are each independently a linear alkyl group having 1 to 7 carbon atoms,
An alkoxy group, an alkenyl group, an alkenyloxy group or
C_uH_{2u + 1}-OC_vH_2vAnd u and v are each independently
Represents an integer of 1 to 5;³¹Is H, F or -CH_ThreeThe table
Then Y³²And Y³³Each independently represents H or F;³¹
~ Z³⁴Are each independently a single bond, -COO-, -C_TwoH_Four−
Or -C_FourH₈-Represents Z³¹Also represents -C≡C- or -C
H = CH-, Z³⁵Is a single bond, -C≡C
—, —COO— or —CF ＝ CF—, and a ring A³¹, A
³²Are each independently a cyclohexane ring or cyclohexene
Represents a ring, ring A³³, A³⁴Are each independently cyclohexane
A ring or a phenyl ring, n¹~ N^FiveAre independently 0 or
Represents an integer of 1, and n ^Four+ N^FiveIs 0 or 1, and each compound
Hydrogen atom on the cyclohexane ring in the product is a deuterium atom
It may be replaced. Selected from the group of compounds represented by
Characterized in that they contain one or more compounds
10. The nematic liquid crystal composition according to the above 1 to 9. 11. The liquid crystal component C is a compound represented by the general formula (III-1)
In the object, R³¹Is a linear alkyl having 2 to 5 carbon atoms
Or an alkenyl group,³⁵Has 1 to 5 carbon atoms
Linear alkyl group, alkoxy group, alkenyl group,
A ring A³¹Represents the cyclohexane ring
Then n¹Is 0, Z³²Is a single bond or -COO-
And / or n¹If is 1, Z³¹, Z³²Is simply
10 to 100% by weight of the compound represented by the bond
11. The nematic liquid crystal composition according to the above item 10, wherein 12. The liquid crystal component C is a compound represented by the general formula (III-2)
In the object, R³²Is a linear alkyl having 2 to 5 carbon atoms
Or an alkenyl group,³⁶Has 1 to 5 carbon atoms
Linear alkyl group, alkoxy group, alkenyl group,
Represents a phenyloxy group, n^TwoIs 0, ring A³²But shiku
A cyclohexane ring or a cyclohexene ring;³³Is simple
In the case, -COO- or -C_TwoH_FourA compound represented by-
Is n^TwoIs 1, the ring A³²Is a cyclohexane ring
, Z³³Is a single bond or -C_TwoH_FourCompound represented by-
10. The above-mentioned 10, characterized in that it contains 0 to 100% by weight.
12. The nematic liquid crystal composition according to item 11. 13. The liquid crystal component C is a compound represented by the general formula (III-3)
In the object, Z³⁵Is a compound represented by -C≡C-
The above-mentioned 10, 1 characterized by containing
13. The nematic liquid crystal composition according to items 1 and 12. 14． The liquid crystal material contains at least 70
The composition according to any one of the above items 10 to 13, wherein
Nematic liquid crystal composition. 15. A core structure in which the liquid crystal material has four six-membered rings
A liquid crystal phase-isotropic liquid phase transition of the compound
One or more compounds having a transfer temperature of 100 ° C or higher
The nematic according to any one of the above 1 to 14, characterized by containing
Liquid crystal composition. 16. The liquid crystal material has a dielectric anisotropy of 4 to 30.
Has a birefringence of 0.08 to 0.33, and is 70 ° C. or more.
Is the nematic phase-isotropic liquid phase transition temperature of -10
Crystalline or smectic-nematic phase transition below ℃
The nematic according to any one of the above 1 to 15, which is a temperature.
Liquid crystal composition. 17． The liquid crystal material has an induced helical pitch of 0.5 to 10
Contain a compound having an optically active group of
17. The nematic liquid crystal composition according to any one of the above 1 to 16, wherein
object. 18. 17. The method using the nematic liquid crystal composition described in 17 above.
Active matrix, twisted nematic or
Is a super twisted nematic liquid crystal display
Place. Has been found as a means for solving the above-mentioned problem.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The liquid crystal composition of the present invention contains a liquid crystal component A consisting of a compound represented by the general formula (I-1) as an essential component. The liquid crystal component A has a lower viscosity, a higher birefringence, and a higher elastic constant. For this reason, the liquid crystal composition of the present invention can adjust the birefringence and the elastic constant in a wide range, and has, for example, a characteristic that it can be driven with high contrast and high-speed response. The liquid crystal composition of the present invention contains 1 to 50% by weight of a liquid crystal component A comprising a compound of the general formula (I-1),
It has been found that by including 10 to 99% by weight of a liquid crystal component B composed of a compound having a dielectric anisotropy of 2 or more, faster response characteristics are obtained. The liquid crystal component A is
In addition to the above, when mixed with other liquid crystal materials, improve the nematic phase-isotropic liquid phase transition temperature to a relatively high temperature,
Further, since the compatibility is excellent, the display temperature range can be broadened. Further, the dielectric anisotropy is -2 to +2.
And has higher chemical stability.

From such a viewpoint, the general formula (I-1)
A more preferred form of the compound is¹¹Is ethyl
Group, a compound represented by a propyl group or a butyl group, and
Is R ¹²Is a compound represented by H, and more specifically,
Compounds represented by general formulas (I-2) to (I-47) are preferable,
The liquid crystal component A contains at least one compound in an amount of 30 to
Nematic liquid crystal compositions containing 100% by weight are preferred
No. Each compound is used for distillation, column purification, recrystallization, etc.
Remove impurities using the method
Was.

Embedded image

One or more compounds of the general formula (I-1) can be contained as the liquid crystal component A, but the effects described above can be obtained even if only one compound is used. The liquid crystal composition of the present invention containing a liquid crystal component A containing at least one compound represented by the general formula (I-1) includes TN-LCD, STN-LCD, and TFT-LCD using the same as a constituent material. And the like are made to have more improved electro-optical characteristics, and in particular, the responsiveness, the sharpness, and the temperature dependency of the driving voltage are made more preferable. Particularly preferred compounds from such a viewpoint are those represented by the general formula (I-5):
(I-8), General formulas (I-21) to (I-24), General formula (I-28)
To (I-31) and general formulas (I-44) to (I-47).

The liquid crystal composition of the present invention comprises, in addition to the liquid crystal component A, one or more compounds having a dielectric anisotropy of +2 or more.
It contains a liquid crystal component B containing more than one kind. The term "liquid crystal compound having a dielectric anisotropy greater than 2" used in the present invention has the following meaning. The chemical structure of the liquid crystal compound is rod-shaped, and has a core structure in which the central portion has one to four six-membered rings. A terminal group substituted at a position corresponding to the direction, and at least one of the terminal groups present at both ends is a polar group, that is, for example, -CN, -OCN, -N
_{CS, -F, -Cl, -NO 2} , -CF 3, -OCF 3, -
It is a compound that is OCHF _2. As a result, the optical anisotropy of the liquid crystal layer can be set to a predetermined value, can be electrically driven, and the operating temperature range can be widened.

As the liquid crystal component B, at least one compound having a dielectric anisotropy of +2 or more is required.
Five ranges are preferred. Further, the dielectric anisotropy is +8 to +
It is preferable to appropriately select from among the compounds of 13, the compounds of +14 to +18, and the compounds of +18 or more, so that a predetermined driving voltage and response characteristics can be obtained. in this case,
It is preferable to mix at most 10 or less compounds having a dielectric anisotropy of +8 to +13, and +14 to +18.
It is preferable that at most 8 compounds be mixed in a range of at most 8, and that compounds of +18 or more are mixed at most 10 or less. The use of the liquid crystal component B as described above gives a more favorable effect to the temperature characteristics of the display characteristics. More specifically, it is preferable that the temperature dependency such as the driving voltage, the contrast relating to the steepness, and the response is more preferable.

The liquid crystal component B of the present invention has a general formula (II-
It is preferable to contain 10 to 100% by weight of a compound selected from the compounds represented by 1) to (II-4). More preferred forms of the compounds represented by the general formulas (II-1) to (II-4) are compounds in which R ^{21 to} R ²⁴ are represented by an alkyl group or alkenyl group having 2 to 7 carbon atoms, and / or X ^{21 to} X ²⁴
But F, Cl, -OCF _3, or by selecting the compound represented by -CN, preferably contains at least one kind. In the general formula (II-2), Z ²⁴ is a single bond, -COO-
Alternatively, it is preferable that a compound represented by -C≡C-, a compound represented by the formula (II-3) wherein Z ²⁵ is represented by -C≡C-. Particularly preferred and more specific compounds represented by formulas (II-1) to (II-4) include compounds represented by formula (II-1a)
To (II-4d) are shown below. In addition, each compound was used after removing impurities by a method such as distillation, column purification, recrystallization, etc. and sufficiently purified. The liquid crystal component B containing these compounds has a feature of being well mixed with the liquid crystal component A, which is an essential component, and is particularly useful for adjusting the drive voltage according to the purpose and improving its temperature dependence or response. is there. In particular, general formulas (II-1a) to (II-1h) and general formulas (II-2a) to
The compound (II-4d) is excellent in this effect,
This effect can be obtained even with a small content of%.

Embedded image (Wherein, R ^{21 to} R ²⁴ , X ^{21 to} X ²⁴ , Y ^{21 to} Y ²⁸ , W ^{21 to} W
²⁴ represents the same meaning as described above. )

Further preferred embodiments will be described in detail. R ²¹ is an alkyl group having 2 to 5 carbon atoms or CH ₂ =
A compound which is an alkenyl group of CH- (CH ₂ ) _p (p = 0, 2) is preferable, and compounds of the general formulas (II-1a) and (II-1d) preferably have this group. When at least one compound having an alkenyl group is contained in the polymer, viscosity and viscoelasticity can be reduced. Similarly, a compound in which R ²² is an alkyl group having 2 to 5 carbon atoms or a alkenyl group described above is preferable, and a compound represented by the general formula (II-2a):
The compounds (II-2d), (II-2f) and (II-2g) preferably have this group. X ²¹ to X ²⁴ is F, Cl, -OC
It is preferable to frequently use a compound represented by F ₃ or —CN. When high-speed response is important, general formulas (II-1a), (II-1d), and (II) in which X ^{21 to} X ²⁴ are F and —OCF ₃ are used. -2a), (II-2
It is preferable that the compounds of c), (II-2d), (II-2g) and (II-3a) are frequently used in the liquid crystal component B. When a larger birefringence is required, X ^{22 to} X ²⁴ are preferably used. Cl, -OCF _3, -C
It is preferable to frequently use the compounds of the general formulas (II-2a) to (II-4d) which are N for the liquid crystal component B. When a lower driving voltage is required, X ²¹ is -CN and Y ²¹ is H or F A compound of the general formulas (II-1a) to (II-1g), wherein X ²² is F, Cl, −
General formulas (II-2a) to (II-2) in which Y ²³ is H or F in CN
Compounds of f), X ²³ is F, Cl, compounds of general formula Y ²⁵ is F at -CN (II-3a) ~ ( II-3c), X 24 is F, C
l, the general formula Y ²⁷ is F at -CN (II-4a) ~ ( II-4
It is preferred that the compound of d) is frequently used in the liquid crystal component B.
In particular, active matrix display, TFT-LCD, MIM
-Light scattering type liquid crystal display devices having a super TFT or active matrix technology combined with LCD and IPS mode (for example, display devices having a light control layer containing a liquid crystal material and a transparent solid substance) are X ²¹ It is preferable to frequently use a compound in which -X ²⁴ is -F.

In general formulas (II-1) to (II-4),
When responsiveness is important Y^{twenty one}~ Y²⁸Is H and / or W^{twenty one}~
W^{twenty four}Can be used frequently, and the driving voltage
To improve the temperature dependence of^{twenty one}~ Y²⁸Is F, W^{twenty one}~
W^{twenty four}Is F, particularly preferably Y^{twenty one}, Y^{twenty three},
Y^{twenty five}, Y²⁷, W^{twenty one}~ W^{twenty four}Frequently use compounds in which
Is preferable, in which W^{twenty one}And W^{twenty two}If F is Y
^{twenty four}If the compound of which is H is selected, the compatibility can be further improved.
In the case of general formula (II-3), W^{twenty three}And / or W^{twenty four}Is F
By selecting such a compound, the compatibility can be further improved. General formula
In (II-1), Z ^{twenty one}And Z^{twenty two}One is a single bond compound
Is preferable, in order to improve the responsiveness and compatibility at low temperatures,
Single bond compound and -COO-, -C_TwoH_Four-, -C_FourH₈−
It is preferable to use the liquid crystal component B in combination with the compound of
No. If you need a higher birefringence,
Z in general formulas (II-2) and (II-3)^{twenty four}, Z^{twenty five}Is -C≡C
And X in the general formula (II-4)^{twenty four}Is C
It is preferable that the compound of N is frequently used in the liquid crystal component B. one
M in general formulas (II-1), (II-2) and (II-4)¹~ M^FourBut
And a compound represented by formula (II-1) or (II-2)
m¹, M^TwoA compound represented by the formula (II-4)^Three+
m^FourWith the compound of formula 1 and / or the compound of general formula (II-3)
The mixing ratio of the liquid crystal component B is from 0 to 100 to 100 to 0.
Timely selection in the range, higher nematic phase-etc.
When an isotropic liquid phase transition temperature is required, the general formula (II-
1), m in (II-2)¹, M^TwoIs a compound of the general formula
A compound of the formula (II-3) and / or m in the general formula (II-4)^Three
+ M^FourIt is preferable to frequently use one compound. General formula
Hydrogen atoms in the cyclohexane ring of (II-1) and (II-2)
Compounds substituted with deuterium atoms can be used
However, this compound adjusts the elastic constant of the liquid crystal composition and
It is useful for adjusting the pretilt angle corresponding to
Contains at least one compound substituted with a deuterium atom
It is preferred to have.

The effect of the liquid crystal component B described above can be obtained even when the content of the liquid crystal component C described later is very small. For the purpose of particularly lowering the driving voltage, the content of the liquid crystal component C can be reduced to 10% by weight or less. In this case, it is preferable to make the viscosity of the liquid crystal component C as low as possible, and the drive voltage is hardly increased or stays in a small range, so that the response speed can be efficiently improved. For example, when the amount of the liquid crystal component C is small, a method for achieving this effect with the liquid crystal component B is represented by formulas (II-1) to (II-1).
In (II-4), X ^{21 to} X ²⁴ represent F, Cl, and —OCF _3.
Or a compound in which Y ^{21 to} Y ²⁴ are F, a compound in which Z ²⁴ and Z ²⁵ are —COO—, —C≡C—, or a compound in which m ¹ is 1. Is preferably contained. In particular, general formulas (II-1) to
In (II-4), X ^{21 to} X ²⁴ represent F, Cl, —OCF ₃ ,
Compounds in which —CN and / or Y ^{21 to} Y ²³ are F are preferred.

The liquid crystal composition of the present invention comprises, in addition to the liquid crystal component A and the liquid crystal component B which are essential components, a liquid crystal component C comprising a compound having a dielectric anisotropy of -2 to 2 at most.
It is preferred that the content be contained by weight. -2 described in the present invention
Preferred examples of the liquid crystal compound having a dielectric anisotropy of 1 to 2 are shown below. That is, the chemical structure of the liquid crystal compound is rod-shaped, the central portion has a core structure having 1 to 4 six-membered rings, and the six-membered rings located at both ends in the major axis direction of the central portion are formed of liquid crystal molecules. It has a terminal group substituted at a position corresponding to the major axis direction, and both terminal groups present at both ends are non-polar groups, that is, for example, an alkyl group, an alkoxy group, an alkoxyalkyl group, an alkenyl group, an alkenyloxy group. And alkanoyloxy groups. The liquid crystal component C is preferably composed of at least one type and at most 20 types, and more preferably at least two types and at most 12 types.

The liquid crystal component C of the present invention has the general formula (III-
It is preferable to contain 10 to 100% by weight of a compound selected from the compounds represented by 1) to (III-4). As particularly preferred compounds represented by formulas (III-1) to (III-4), formulas (III-1a) to (III-4e) are shown below. The liquid crystal component C containing these compounds has the general formula (I-1)
The compound has a feature of being well mixed with the liquid crystal component A containing the compound of formula (1), and is useful for improving a nematic phase at a low temperature.

Embedded image (In the formula, R ^{31 to} R ³⁸ and Y ^{31 to} Y ³³ represent the same meaning as described above.)

As the liquid crystal component C, general formulas (III-1) to (I
By containing the compound of II-4), the viscosity and the viscoelasticity can be reduced and the specific resistance and the voltage holding ratio are relatively high. The viscosity of the liquid crystal component C is preferably as low as possible, and in the case of the present invention, 45 mPa
S or less is preferable, and 30 mPas or less is more preferable.
It is more preferably at most 20 mPa · s, particularly preferably at most 15 mPa · s. General formulas (III-1) to (III)
-4) are more preferably represented by the general formulas (III-1a) to (II-1):
I-3a), (III-3c) to (III-3g), (III-4a), (III-
4d) to (III-4e). R ^{31 to} R ³⁴ are a linear alkyl group having 2 to 5 carbon atoms or CH ₂ ＣＨCH— (CH ₂ ) _q
The liquid crystal component C containing at least one kind of the compound (q = 0, 2) which is an alkenyl group has a more preferable effect. More particularly, general formulas (III-1a), (III-1d),
A compound of the formula (II-2a), wherein Y ³¹ is a hydrogen atom:
Compounds of I-3c) to (III-3f) and / or a compound of the general formula (III-4a) wherein R ³⁸ is an alkyl group can obtain this effect even when contained in a small amount of 3 to 30%. It is useful for improving the response speed, for example, useful for STN-LCD.

Due to the above-mentioned effects, a more preferable compound to be contained in the liquid crystal component C is a compound represented by the general formula (III-1) wherein R ³¹ is a linear alkyl group having 2 to 5 carbon atoms or Represents an alkenyl group, wherein R ³⁵ has 1 to 4 carbon atoms
Represents a linear alkyl group, an alkoxy group, an alkenyl group, an alkenyloxy group, ring A ³¹ represents a cyclohexane ring, and when n ¹ is 0, Z ³² is a single bond or —COO—, and n ¹ is In the case of 1, Z ³¹ and Z ³² are compounds represented by a single bond, and in the compound of the general formula (III-2),
³² represents a linear alkyl group or alkenyl group having 2 to 5 carbon atoms, R ³⁶ represents a linear alkyl group, alkoxy group, alkenyl group or alkenyloxy group having 1 to 4 carbon atoms, and n ² Is 0, ring A ³² is a cyclohexane ring or a cyclohexene ring, Z ³³ is a single bond, -COO-
Or -C ₂ H ₄ -. And, in the case where n ² is 1, the ring A ³² is cyclohexane ring, Z ³³ is a single bond or -C ₂ H ₄ - is a compound represented by.

The liquid crystal component C of the present invention has the general formula (III-
1), general formula (III-2), general formula (III-3), general formula (III
-4), the compound represented by the general formulas (III-1) and / or (III-2) and the compounds represented by the general formulas (III-3) and / or By using a compound represented by (III-4), particularly a compound wherein Z ³⁵ is represented by —C≡C—, the birefringence of the liquid crystal composition can be easily optimized according to the intended use. . General formula (III-
1) a compound of the general formula (III-2), for example, a compound of the general formula (III-1)
a) The birefringence can be reduced by frequently using the compounds of (III-2f), and it is possible to easily achieve a reduction in color unevenness, an improvement in viewing angle characteristics, and an increase in contrast ratio of a liquid crystal display device. Can be. Also, a compound of the general formula (III-3), for example, a compound of the general formulas (III-3a) to (III-3h), or a compound of the general formula (III-4), for example, the general formula (III-4)
By frequently using the compounds a) to (III-4e), the birefringence can be increased, and a thin liquid crystal display element having a liquid crystal layer of 1 to 5 μm can be manufactured.

When the liquid crystal composition of the present invention is intended to have a quicker response to the magnitude of the driving voltage, the following can be achieved. When a medium drive voltage is intended, the liquid crystal composition of the present invention preferably has a dielectric anisotropy in the range of 3 to 15 and a viscosity at 20 ° C. in the range of 8 to 20 mPa · s. . In this case, the viscosity of only the liquid crystal component C is preferably 25 mPa · s or less, more preferably 15 mPa · s or less, and particularly preferably 10 mPa · s or less. When a particularly low driving voltage is intended, the dielectric anisotropy of the liquid crystal composition of the present invention is preferably in the range of 15 to 30, and particularly preferably in the range of 18 to 28.

At present, TN-LCD, STN-LCD or TFT-LCD
Polyimide-based alignment films are often used
For example, LX1400, SE150, SE610, AL1051, AL34
08 etc. are used. The specifications of the alignment film include liquid crystal display characteristics.
Performance, display quality, reliability, and productivity are closely related.
For example, pretilt angle characteristics are important for crystalline materials.
You. The magnitude of the pretilt angle depends on the desired liquid crystal display characteristics and uniformity.
In order to obtain a uniform orientation, it is necessary to make appropriate adjustments. An example
For example, in the case of a large pretilt angle, an unstable alignment state is obtained.
If it is small, it may not satisfy the sufficient display characteristics.
And The present inventors have proposed a liquid having a larger pretilt angle.
To be divided into crystalline materials and smaller liquid crystal materials
By applying this, the desired liquid crystal display
To achieve display characteristics and uniform orientation from liquid crystal materials.
I found it. This technique can be applied to the present invention. example
For example, the liquid crystal component B contains the general formulas (II-1) to (II-4)
The case is as follows. The larger pretilt angle is
R^{twenty one}Is an alkenyl group, X^{twenty one}Is F, Cl, -CN, Y^{twenty one},
Y^{twenty two}Is a compound of F and / or R^{twenty one}Is an alkyl group, X^{twenty one}But
F, Cl, -CN, Z^{twenty two}Is -C_TwoH_Four-, -C_FourH₈-
Higher content of the compound
The retilt angle is R^{twenty one}Is an alkenyl group, C _sH_{2s + 1}-O-
C_tH_2t, X^{twenty one}Is F, Y^{twenty one}Is F, Y^{twenty two}Is a compound of H and also
Is Z^{twenty two}To increase the content of -COO- compound
Is obtained. Cyclo in general formulas (II-1) and (II-2)
Field of compound in which hydrogen atom of hexane ring is replaced with deuterium atom
The pre-tilt angle
Make adjustment possible. Such effects are, for example, greater
When a pretilt angle is obtained, the compound described above is used in a liquid crystal composition.
10 to 40% by weight or more based on the total amount
It can be almost obtained by doing.

The compound of the general formula (I-1) according to the present invention, which will be described later, is more useful than the compounds of the general formulas (a-1) and (a-2) in compatibility and response characteristics. A liquid crystal composition can be manufactured. In particular, the STN-LCD was found to simultaneously improve the steepness and responsiveness, which are in a trade-off relationship. This effect is considered to be due to having an alkenyl group in the liquid crystal molecule skeleton, Z ¹¹ being —C≡C—, and ring A ¹¹ being monofluorinated.

The content of each liquid crystal component in the nematic liquid crystal composition of the present invention can be as follows. Liquid crystal component A
Is in the range of 1 to 50% by weight, preferably in the range of 3 to 40% by weight, and more preferably in the range of 3 to 30% by weight. The liquid crystal component B is in the range of 10 to 99% by weight,
A range of 25 to 90% by weight is preferred, and 25 to 80% by weight.
Is more preferable. The content of the liquid crystal component C is at most 70% by weight, preferably 3 to 65% by weight, more preferably 5 to 60% by weight, and more preferably 10 to 55% by weight.
The range of weight% is more preferred. The content of the compound represented by the general formula (I-1) is preferably 20% by weight or less as a single substance, and more than 20% by weight is preferably composed of two or more kinds. The general formulas (I-2) to (I- The content of the compound represented by 7) with respect to the liquid crystal component A is in the range of 50 to 100% by weight.
A range from 70 to 100% by weight is preferred. General formula (II-1)
Or a compound represented by the formula (II-1a):
The content of the compound represented by the formula (II-4d) is 30
% By weight, more preferably 25% by weight or less, and more preferably 25% by weight or more, and the content of the liquid crystal component B is in the range of 10 to 100% by weight. %, Preferably 75%
The range of -100% by weight is more preferable. General formula (III-
Compounds represented by 1) to (III-4) or the general formula (III-
The content of the compounds represented by 1a) to (III-4e) is preferably 30% by weight or less, more preferably 25% by weight or less, and more preferably 2 or more types,
The content with respect to the liquid crystal component C is in the range of 10 to 100% by weight, preferably in the range of 50 to 100% by weight.
The range of 5 to 100% by weight is more preferable.

The crystalline phase or the smectic phase-nematic phase transition temperature is preferably -10 ° C or lower, more preferably -20 ° C or lower, and particularly preferably -30 ° C or lower. The nematic phase-isotropic liquid phase transition temperature is 60 ° C. or higher, preferably 70 ° C. or higher, and more preferably 80 ° C. to 130 ° C.
Range. The liquid crystal composition of the present invention requires a dielectric anisotropy of 3 or more, preferably in the range of 4 to 40, and in the case of emphasizing high-speed response, the range of 4 to 16 requires a lower driving voltage. If so, the range of 17 to 30 is preferable.
The smaller or medium birefringence is between 0.09 and 0.1
8 is preferred and the larger birefringence is 0.18.
The range of -0.33 is preferable. Such properties of the nematic liquid crystal composition are useful for use in an active matrix type, twisted nematic or super twisted nematic liquid crystal display device.

The nematic liquid crystal composition is useful for TN-LCDs and STN-LCDs having a high response speed, and can perform color display by using the birefringence between the liquid crystal layer and the retardation plate without using a color filter layer. The present invention is useful for a liquid crystal display device which can be used, and a transmissive or reflective liquid crystal display device can be used. This liquid crystal display element has a substrate having a transparent electrode layer and at least one of which is transparent, and the molecules of the nematic liquid crystal composition are twisted between the substrates. °, preferably from 90 ° to 270 °, preferably from 45 ° to 135 ° or from 180 ° to 26 °.
It is particularly preferred to select in the range of 0 °. For this,
The liquid crystal composition of the present invention has an induced helical pitch of 0.5 to 10
A compound having an optically active group having a thickness of 00 μm can be contained. The pretilt angle obtained by the alignment film provided on the transparent electrode substrate is preferably selected in the range of 1 ° to 20 °, and the twist angle is preferably 30 ° to 100 °, and the pretilt angle of 1 ° to 4 ° is preferable. 100 ° -1
At 80 °, a pretilt angle of 2 ° to 6 ° is preferable.
For 0 ° to 260 °, a pretilt angle of 3 ° to 12 ° is preferable, and for 260 ° to 360 °, a pretilt angle of 6 ° to 20 ° is preferable.

The liquid crystal composition of the present invention has the above general formula (I-
1) In addition to the compounds represented by (III-4), in order to improve the characteristics of the liquid crystal composition, the liquid crystal composition contains a normal nematic liquid crystal, a smectic liquid crystal, a cholesteric liquid crystal, and the like which are recognized as a liquid crystal compound. Is also good. However, if these compounds are used in large amounts, the properties of the nematic liquid crystal composition will be reduced, so that the amount of addition is limited according to the required properties of the obtained nematic liquid crystal composition.

[0030]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Further, “%” in the compositions of the following examples means “% by weight”. The chemical stability of the composition was measured by placing 2 g of the liquid crystal composition in an ampoule tube, performing a process of purging with nitrogen after degassing in a vacuum, and performing a heating promotion test at 150 ° C. for 1 hour. The specific resistance or voltage holding ratio was measured. The characteristics measured in the examples are as follows.

T _NI : Nematic phase-isotropic liquid phase transition temperature (° C.) T _{→ N} : Solid phase or smectic phase-nematic phase transition temperature (° C.) Vth: TN-LCD having a cell thickness of 6 μm Threshold voltage (V) γ: ratio of saturation voltage (Vsat) to Vth Δε: dielectric anisotropy Δn: birefringence η: viscosity at 20 ° C. (mPa · s)

(Example 1)

Embedded image Was prepared, and various properties of the composition were measured. The results were as follows. _{T NI: 86.7 ℃ T → N} : -20.0 ℃ Vth: 2.02 V γ: 1.21 △ ε: 5.5 △ n: 0.146 η: 15.3 mPa · s test before Specific resistance: 2.4 × 10 ¹³ Ω · cm Specific resistance after heating promotion test: 7.2 × 10 ¹² Ω · cm Voltage holding ratio before test: 99.4% Voltage holding ratio after heating promotion test: 98. 9%

Since the nematic liquid crystal composition has a high specific resistance and a high voltage holding ratio after the heating acceleration test, it can be understood that the composition is thermally stable. Further, a new nematic liquid crystal composition of the present invention using this composition as a basic constituent material was prepared, and an active matrix liquid crystal display device using the same was prepared. Was confirmed. Furthermore, in the same manner, another nematic liquid crystal composition of the present invention using this composition as a basic constituent material was prepared, and a twisted nematic and a super twisted nematic liquid crystal display device were prepared. It was confirmed that the product was excellent without flicker.

A liquid crystal mixture was prepared by adding a chiral substance "S-811" (manufactured by Merck) to the liquid crystal composition (2-1). On the other hand, "San Ever
An alignment film was formed by rubbing an organic film of “150” (manufactured by Nissan Chemical Industries, Ltd.) to produce an STN-LCD display cell having a twist angle of 240 °. The mixed liquid crystal was injected into this cell to construct a liquid crystal display, and the display characteristics were measured. As a result, a liquid crystal display device exhibiting STN-LCD display characteristics with excellent high time division characteristics and improved fast response was obtained. Note that the chiral substance has a specific helical pitch P of the mixed liquid crystal due to the addition of the chiral substance and a cell thickness d of the display cell, Δn · d = 0.85,
It was added so that d / P = 0.50. STN-LCD display characteristics with a twist angle of 240 degrees Vth: 2.39 Vγ: 1.031 Response (τr = τd): 17.0 msec (static drive)

For the purpose of comparison, the liquid crystal composition (2-
1) A liquid crystal composition was prepared in which the compound of the general formula (a-1) was mixed instead of the compound of the general formula (I-21). When the STN-LCD characteristics were measured, the characteristics were as follows, and it was found that the use of the compound of the general formula (I-21) was able to simultaneously improve the steepness and responsiveness, which are in a trade-off relationship. . STN-LCD display characteristics with a twist angle of 240 degrees Vth: 2.41 Vγ: 1.076 Response (τr = τd): 19.6 msec (static drive)

For the purpose of comparison, the liquid crystal composition (2-
1) A liquid crystal composition was prepared by mixing the compound of the general formula (a-2) in place of the compound of the general formula (I-21), but the compatibility was poor and the compound was precipitated at room temperature. The compound of the general formula (I-1) according to the present invention can produce a liquid crystal composition useful for compatibility and response characteristics, for example, as compared with the compounds of the general formulas (a-1) and (a-2). Can be. In particular, the STN-LCD was found to simultaneously improve the steepness and responsiveness, which are in a trade-off relationship. This effect is considered to be due to having an alkenyl group in the liquid crystal molecule skeleton, Z ¹¹ being —C≡C—, and ring A ¹¹ being monofluorinated.

Example 2 A nematic liquid crystal composition was prepared by replacing the compound of the general formula (I-21) of Example 1 with the general formula (I-2).

Example 3 A nematic liquid crystal composition was prepared by changing the compound of the general formula (I-21) of Example 1 to the general formula (I-3).

Example 4 A nematic liquid crystal composition was prepared by changing the compound of the general formula (I-21) of Example 1 to the general formula (I-4).

Example 5 A nematic liquid crystal composition was prepared by changing the compound of the general formula (I-21) of Example 1 to the general formula (I-5).

Example 6 A nematic liquid crystal composition was prepared by changing the compound of the general formula (I-21) of Example 1 to the general formula (I-6).

Example 7 A nematic liquid crystal composition was prepared by changing the compound of the general formula (I-21) of Example 1 to the general formula (I-7).

Example 8 A nematic liquid crystal composition was prepared by changing the compound of the general formula (I-21) of Example 1 to the general formula (I-8).

Example 9 A nematic liquid crystal composition was prepared by changing the compound of the general formula (I-21) of Example 1 to the general formula (I-9).

Example 10 The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-10).

(Example 11) The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-11).

(Example 12) The general formula (I-21) of Example 1
Was changed to the general formula (I-12) to produce a nematic liquid crystal composition.

Example 13 The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-13).

(Example 14) The general formula (I-21) of Example 1
Was converted to the general formula (I-14) to produce a nematic liquid crystal composition.

Example 15 The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-15).

(Example 16) The general formula (I-21) of Example 1
Was converted to the general formula (I-16) to produce a nematic liquid crystal composition.

Example 17 The general formula (I-21) of Example 1
Was converted to the general formula (I-17) to produce a nematic liquid crystal composition.

Example 18 The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-18).

Example 19 The general formula (I-21) of Example 1
Was converted to the general formula (I-19) to produce a nematic liquid crystal composition.

(Example 20) The general formula (I-21) of Example 1
Was changed to the general formula (I-20) to prepare a nematic liquid crystal composition.

(Example 21) The general formula (I-21) of Example 1
Was changed to the general formula (I-22) to produce a nematic liquid crystal composition.

(Example 22) The general formula (I-21) of Example 1
Was converted to the general formula (I-23) to produce a nematic liquid crystal composition.

Example 23 The general formula (I-21) of Example 1
Was changed to the general formula (I-24) to produce a nematic liquid crystal composition.

(Example 24) The general formula (I-21) of Example 1
Was changed to the general formula (I-25) to prepare a nematic liquid crystal composition.

(Example 25) The general formula (I-21) of Example 1
The compound of formula (I-26) was replaced with a nematic liquid crystal composition.

(Example 26) The general formula (I-21) of Example 1
Was converted to the general formula (I-27) to produce a nematic liquid crystal composition.

(Example 27) The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-28).

(Example 28) The general formula (I-21) of Example 1
Was converted to the general formula (I-29) to produce a nematic liquid crystal composition.

(Example 29) General formula (I-21) of Example 1
Was converted to the general formula (I-30) to produce a nematic liquid crystal composition.

(Example 30) The general formula (I-21) of Example 1
Was changed to the general formula (I-31) to produce a nematic liquid crystal composition.

(Example 31) The general formula (I-21) of Example 1
Was changed to the general formula (I-32) to produce a nematic liquid crystal composition.

(Example 32) The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-33).

Example 33 The general formula (I-21) of Example 1
Was converted to the general formula (I-34) to produce a nematic liquid crystal composition.

Example 34 The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of formula (I) to the general formula (I-35).

(Example 35) The general formula (I-21) of Example 1
Was converted to the general formula (I-36) to produce a nematic liquid crystal composition.

(Example 36) The general formula (I-21) of Example 1
Was converted to the general formula (I-37) to produce a nematic liquid crystal composition.

(Example 37) The general formula (I-21) of Example 1
Was converted to the general formula (I-38) to produce a nematic liquid crystal composition.

(Example 38) The general formula (I-21) of Example 1
Was converted to the general formula (I-39) to produce a nematic liquid crystal composition.

(Example 39) The general formula (I-21) of Example 1
Was changed to the general formula (I-40) to produce a nematic liquid crystal composition.

(Example 40) The general formula (I-21) of Example 1
Was converted to the general formula (I-41) to produce a nematic liquid crystal composition.

(Example 41) The general formula (I-21) of Example 1
Was converted to the general formula (I-42) to produce a nematic liquid crystal composition.

(Example 42) The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-43).

Example 43 The general formula (I-21) of Example 1
A nematic liquid crystal composition was prepared by changing the compound of the formula into the general formula (I-44).

Example 44 The general formula (I-21) of Example 1
Was converted to the general formula (I-45) to produce a nematic liquid crystal composition.

(Example 45) The general formula (I-21) of Example 1
Was converted to the general formula (I-46) to produce a nematic liquid crystal composition.

(Example 46) The general formula (I-21) of Example 1
Was converted to the general formula (I-47) to produce a nematic liquid crystal composition.

(Embodiment 47)

Embedded image Was prepared, and various properties of the composition were measured. The results were as follows. _{T NI: 88.7 ℃ T → N} : -28.0 ℃ Vth: 2.13 V γ: 1.22 △ ε: 5.8 △ n: 0.215 η: 16.1 mPa · s

A chiral substance “S-811” (manufactured by Merck) was added to this nematic liquid crystal composition to prepare a mixed liquid crystal. On the other hand, "San Ever
An alignment film was formed by rubbing an organic film of “150” (manufactured by Nissan Chemical Industries, Ltd.) to produce an STN-LCD display cell having a twist angle of 240 °. The mixed liquid crystal was injected into this cell to construct a liquid crystal display, and the display characteristics were measured. As a result, a liquid crystal display device exhibiting STN-LCD display characteristics with excellent high time division characteristics and improved fast response was obtained. Note that the chiral substance has a specific helical pitch P of the mixed liquid crystal due to the addition of the chiral substance and a cell thickness d of the display cell, Δn · d = 0.85,
It was added so that d / P = 0.50. STN-LCD display characteristics with a twist angle of 240 degrees Vth: 2.39 Vγ: 1.034 Response (τr = τd): 16.8 msec (static drive)

For the purpose of comparison, the liquid crystal composition (2-
2) A liquid crystal composition was prepared in which the compound of the general formula (a-1) was mixed instead of the compound of the general formula (I-21). When the STN-LCD characteristics were measured, the characteristics were as follows, and it was found that the use of the compound of the general formula (I-21) was able to simultaneously improve the steepness and responsiveness, which are in a trade-off relationship. . STN-LCD display characteristics with a twist angle of 240 degrees Vth: 2.44 Vγ: 1.082 Response (τr = τd): 19.3 msec (static drive)

For the purpose of comparison, the liquid crystal composition (2-
2) A liquid crystal composition was prepared by mixing the compound of the general formula (a-2) in place of the compound of the general formula (I-21). However, the liquid crystal composition was poor in compatibility and precipitated at room temperature. The compound of the general formula (I-1) according to the present invention can produce a liquid crystal composition useful for compatibility and response characteristics, for example, as compared with the compounds of the general formulas (a-1) and (a-2). Can be. In particular, the STN-LCD was found to simultaneously improve the steepness and responsiveness, which are in a trade-off relationship. This effect is considered to be due to having an alkenyl group in the liquid crystal molecule skeleton, Z ¹¹ being —C≡C—, and ring A ¹¹ being monofluorinated.

(Embodiment 48)

Embedded image A nematic liquid crystal composition (2-3) was prepared, and various characteristics of the composition were measured. The results were as follows. T _NI : 90.6 ° C. T _{→ N} : −41.0 ° C. Vth: 1.08 V γ: 1.28 Δε: 15.5 Δn: 0.145 η: 45.3 mPa · s

A chiral substance “S-811” (manufactured by Merck) was added to the nematic liquid crystal composition (2-3) to prepare a mixed liquid crystal. On the other hand, an organic film of “Sun Ever 150” (manufactured by Nissan Chemical Industries, Ltd.) was rubbed on the opposed flat transparent electrode to form an alignment film, and an STN-LCD display cell having a twist angle of 240 ° was manufactured. The mixed liquid crystal was injected into this cell to construct a liquid crystal display, and the display characteristics were measured. As a result, a liquid crystal display device exhibiting STN-LCD display characteristics with excellent high time division characteristics and improved fast response was obtained. Note that the chiral substance is such that the specific helical pitch P of the mixed liquid crystal due to the addition of the chiral substance and the cell thickness d of the display cell are Δnd · 0.8
5, It was added so that d / P = 0.50. STN-LCD display characteristics with a twist angle of 240 degrees Vth: 1.10 Vγ: 1.057 Response (τr = τd): 48.3 msec (static drive)

For the purpose of comparison, the liquid crystal composition (2-
3) A liquid crystal composition was prepared in which the compound of the general formula (a-1) was mixed instead of the compound of the general formula (I-5). When the STN-LCD characteristics were measured, the characteristics were as follows, and it was found that the use of the compound of the general formula (I-5) was able to simultaneously improve the steepness and responsiveness, which are in a trade-off relationship. . STN-LCD display characteristics with a twist angle of 240 degrees Vth: 1.08 Vγ: 1.083 Response (τr = τd): 52.7 msec (static drive)

For the purpose of comparison, the liquid crystal composition (2-
3) A liquid crystal composition was prepared by mixing the compound of the general formula (a-2) in place of the compound of the general formula (I-5). However, the liquid crystal composition was poor in compatibility and precipitated at room temperature. The compound of the general formula (I-1) according to the present invention can produce a liquid crystal composition useful for compatibility and response characteristics, for example, as compared with the compounds of the general formulas (a-1) and (a-2). Can be. In particular, the STN-LCD was found to simultaneously improve the steepness and responsiveness, which are in a trade-off relationship. This effect is considered to be due to having an alkenyl group in the liquid crystal molecule skeleton, Z ¹¹ being —C≡C—, and ring A ¹¹ being monofluorinated.

(Embodiment 49)

Embedded image A nematic liquid crystal composition (2-4) was prepared.

(Example 50)

Embedded image A nematic liquid crystal composition (2-5) was prepared.

(Example 51)

Embedded image A nematic liquid crystal composition (2-6) was prepared.

(Example 52)

Embedded image A nematic liquid crystal composition (2-7) was prepared.

(Example 53)

Embedded image A nematic liquid crystal composition (2-8) was prepared.

[0095]

The nematic liquid crystal composition of the present invention has a relatively large birefringence .DELTA.n, exhibits a nematic phase in a wide temperature range, has excellent effects of improving response characteristics, has an excellent effect of improving contrast, and has a high voltage. It is clear that the retention is high and the chemical stability is high. Therefore, the nematic liquid crystal composition of the present invention can be used for an active matrix type, twisted nematic or super twisted nematic liquid crystal display device.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C09K 19/46 C09K 19/46 G02F 1/13 500 G02F 1/13 500 F term (reference) 4H027 BA01 BB03 BB04 BC04 BC05 BD01 BD02 BD04 BD07 BD08 BD20 BE03 CB01 CC04 CD04 CE02 CE04 CE05 CG02 CG04 CG05 CM04 CN01 CN02 CP02 CP05 CQ02 CQ03 CQ04 CT01 CT02 CT04 CT05 CU01 CW02 DP01

Claims (18)

[Claims] 1. A liquid crystal composition represented by the general formula (I-1): (Wherein, R ¹¹ represents a linear alkyl group or alkenyl group having 2 to 10 carbon atoms, and R ¹² represents H or 1 to carbon atoms.
5 represents a linear alkyl group, A ¹¹ represents a cyclohexane ring or a benzene ring or a monofluorinated benzene ring,
Z ¹¹ represents a single bond or —C≡C—. However, when A ¹¹ is a cyclohexane ring, Z ¹¹ is -C≡C-. ) Containing a liquid crystal component A composed of one or more compounds, and a liquid crystal component B composed of a compound having a dielectric anisotropy of +2 or more, wherein the liquid crystal material has a dielectric constant of +3 or more. Nematic phase at 60 ° C. or higher—isotropic liquid phase transition temperature, crystal phase or smectic phase at 0 ° C. or lower—
A nematic liquid crystal composition having a nematic phase transition temperature. 2. The liquid crystal component A is a compound in which R ¹¹ in the general formula (I-1) is an ethyl group, a propyl group or a butyl group and / or a compound in which R ¹² is H.
2. The nematic liquid crystal composition according to claim 1, wherein the composition comprises 100% by weight. 3. The liquid crystal material according to claim 1, wherein the liquid crystal component A is 1 to 3.
The nematic liquid crystal composition according to claim 1, wherein the composition comprises 50% by weight. 4. The method according to claim 1, wherein the liquid crystal component B has a general formula (II-1)
(II-4) (Wherein, R ^{21 to} R ²⁴ each independently represent 2 to 10 carbon atoms.
Linear alkyl group, alkenyl group or C _s H _{2s + 1} -O
Represents -C _t H _2t, s and t are each independently an integer of 1~5, X ²¹ ~X ²⁴ are each independently F, Cl, -OC
F ₃ , —OCHF ₂ , —CF ₃ or —CN, and Y ^{21 to} Y ^21
28 each independently represent H or F, W ²¹ ~W ^{2 4} each independently represents H or F, Z ²¹ ~Z ²³ each independently represents a single bond, -COO -, - C ₂ H ₄ - or -C ₄ H ₈ - represents, Z
²¹ may also be -C≡C- or -CH = CH-, and Z ²⁴ and Z ²⁵ each independently represent a single bond, -COO-,-
C≡C— or —CF ＝ CF—, m ^{1 to} m ⁴ each independently represent 0 or 1, m ³ + m ⁴ is 0 or 1, and the hydrogen atom of the cyclohexane ring in each compound is a heavy atom. It may be substituted by a hydrogen atom D (hereinafter used in this meaning). The nematic liquid crystal composition according to any one of claims 1 to 3, further comprising a compound selected from the group consisting of compounds represented by the formula: 5. The liquid crystal component B according to the general formula (II-1)
Compounds in which R ^{21 to} R ²⁴ in (II-4) are an alkyl group or alkenyl group having 2 to 5 carbon atoms, and / or X ²¹
5. The nematic liquid crystal composition according to claim 4, wherein a compound in which X ²⁴ is F, Cl, —OCF ₃ , or —CN contains 10 to 100% by weight. 6. The liquid crystal component B according to the general formula (II-1)
Z in the compound of ^{twenty one}, Z^{twenty two}Is a single bond, -COO-,-
C_TwoH_Four-Or -C_FourH₈The compound represented by-is 10 to 10
6. The composition according to claim 4, which contains 0% by weight.
Nematic liquid crystal composition. 7. The liquid crystal component B represented by the general formula (II-2)
Z in the compound of ^{twenty four}Is a single bond, -COO- or -C≡
10 to 100% by weight of the compound represented by C-
7. The nematic liquid crystal composition according to claim 4, wherein
object. 8. The liquid crystal component B according to the general formula (II-3)
Z in the compound of ^{twenty five}Is represented by a single bond or -C≡C-
At least 10% by weight of the compound
The nematic liquid crystal composition according to claim 4, wherein 9. The liquid crystal material according to claim 1, wherein
The nematic liquid crystal composition according to any one of claims 1 to 8, wherein the content is from 9 to 99% by weight. 10. The liquid crystal material has a dielectric constant of -2 to 2.
A liquid crystal component C comprising an anisotropic compound;
The crystal component C has a general formula (III-1) to (III-4)(Where R³¹~ R³⁴Each independently has 2 to 7 carbon atoms
Represents a linear alkyl group or an alkenyl group,³⁵~ R³⁸
Are each independently a linear alkyl group having 1 to 7 carbon atoms,
An alkoxy group, an alkenyl group, an alkenyloxy group or
C_uH_{2u + 1}-OC_vH_2vAnd u and v are each independently
Represents an integer of 1 to 5;³¹Is H, F or -CH_ThreeThe table
Then Y³²And Y³³Each independently represents H or F;³¹
~ Z³⁴Are each independently a single bond, -COO-, -C_TwoH_Four−
Or -C_FourH₈-Represents Z³¹Also represents -C≡C- or -C
H = CH-, Z³⁵Is a single bond, -C≡C
—, —COO— or —CF ＝ CF—, and a ring A³¹, A
³²Are each independently a cyclohexane ring or cyclohexene
Represents a ring, ring A³³, A³⁴Are each independently cyclohexane
A ring or a phenyl ring, n¹~ N^FiveAre independently 0 or
Represents an integer of 1, and n ^Four+ N^FiveIs 0 or 1, and each compound
Hydrogen atom on the cyclohexane ring in the product is a deuterium atom
It may be replaced. Selected from the group of compounds represented by
Characterized in that they contain one or more compounds
The nematic liquid crystal composition according to claim 1. 11. The liquid crystal component C according to the general formula (III-
In the compound of 1), R ³¹ represents a linear alkyl group or alkenyl group having 2 to 5 carbon atoms, and R ³⁵ represents a linear alkyl group, alkoxy group, alkenyl group, or alkenyl having 1 to 5 carbon atoms. Represents an oxy group, ring A ³¹ represents a cyclohexane ring, and when n ¹ is 0, Z ³² represents a single bond or -C
When the compound represented by OO— and / or n ¹ is 1, Z
^31, Z ³² is 10. nematic liquid crystal composition according to characterized in that it contains 10 to 100 wt% of the compound represented by a single bond. 12. The liquid crystal component C represented by the general formula (III-
In the compound of 2), R ³² represents a linear alkyl group or alkenyl group having 2 to 5 carbon atoms, and R ³⁶ represents a linear alkyl group, alkoxy group, alkenyl group, or alkenyl having 1 to 5 carbon atoms. Represents an oxy group, and when n ² is 0, ring A ³² is a cyclohexane ring or a cyclohexene ring;
When Z ³³ is a single bond, a compound represented by —COO— or —C ₂ H ₄ — and / or when n ² is 1, ring A ³² is a cyclohexane ring, and Z ³³ is a single bond or —C ₂ H ₄ - that it contains 10 to 100 wt% of the compound represented by the nematic liquid crystal composition according to claim 10, 11, wherein the. 13. The liquid crystal component C represented by the general formula (III-
In the compounds of 3), nematic liquid crystal composition according to claim 10, 11 and 12, wherein the Z ³⁵ contains 10 to 100 wt% of the compound represented by -C≡C-. 14. The liquid crystal material according to claim 10, wherein the liquid crystal component C contains at most 70% by weight.
14. The nematic liquid crystal composition according to any one of items 13 to 13. 15. The liquid crystal material is a compound having a core structure having four six-membered rings, and one compound having a liquid crystal phase-isotropic liquid phase transition temperature of 100 ° C. or higher. Or two or more of them.
The nematic liquid crystal composition according to the above. 16. The liquid crystal material has a dielectric anisotropy of 4 to 30, a birefringence of 0.08 to 0.33, and
The liquid crystal composition has a nematic phase-isotropic liquid phase transition temperature of 0 ° C or higher, and a crystal phase or a smectic phase-nematic phase transition temperature of -10 ° C or lower.
The nematic liquid crystal composition according to the above. 17. The nematic liquid crystal composition according to claim 1, wherein the liquid crystal material contains a compound having an optically active group having an induced helical pitch of 0.5 to 1000 μm. 18. An active matrix and a twisted liquid crystal using the nematic liquid crystal composition according to claim 17.
Nematic or super twisted nematic liquid crystal display.