JP2003165977A - Liquid crystal composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a liquid crystal composition which exhibits a negative Δεwith a large absolute value when used in an electro-optical display element, especially in a liquid crystal display element, has a low refractive index anisotropy, and can maintain a high voltage retention up to a high temperature; and to provide the liquid crystal display element using the same. <P>SOLUTION: The liquid crystal composition contains a compound represented by formula (I) and a compound represented by formula (II) such as represented by formula (III), (IV), or (V). The liquid crystal display element is prepared by using this composition. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a nematic liquid crystal composition useful as an electro-optical liquid crystal display material, and a liquid crystal display device using the nematic liquid crystal composition.

[0002]

2. Description of the Related Art A liquid crystal display device (LCD) has been used as a calculator display, and has been in the same process as the development of computers. From TN-LCD (twisted nematic liquid crystal display device) to STN-LCD. It has responded to the expansion of capacity. STN-L
CDs include Scheffer [SID '85 Digest, 120
Page (1985)], or Kinugawa et al. [SID '86 Digest, 122
Page (1986)], developed by
It has begun to spread widely in displays for high information processing such as personal computers. In particular, an active matrix liquid crystal display device (AM-LCD) with a thin film transistor attached to each pixel
Is expected to be the most promising display with high image quality that can be substituted for CRT, flattening and energy saving. The active matrix display method uses a TFT (thin film transistor) for each pixel
Alternatively, MIM (Metal Insulator Metal) is used, and it is important for this method to have a high voltage holding ratio. In TN type liquid crystal display elements and STN type liquid crystal display elements, liquid crystal molecules that are twisted and aligned in parallel to the substrate when voltage is applied rise vertically to eliminate twisting and control the light and darkness of light to perform display. There is. In this way, when the liquid crystal molecules rise from the initial twisted state, the twisted state varies depending on the viewing angle of the observer, which causes contrast deterioration and color reversal, resulting in a narrow effective viewing angle.

In order to obtain wide viewing angle characteristics, IPS (Inplane sw
i TFT) combined with Super TFT [Asia Displ
ay '95 Digest, p.707 1995], MVA (Multi-domain Ver
VA (Vertically Alingnement) represented by
d) is proposed. In addition to these, OCB (Optically
Compensated Birefringence mode; JP-A-7-84254, SID93DIGEST, p277), ECB (Electrically Controlled)
It has been reported that an active matrix display system is used for Birefringence), PC, PSCT, etc. (hereinafter, these active matrix display system liquid crystal display devices are collectively referred to as TFT-LCD). In order to deal with the above, new liquid crystal compounds or liquid crystal compositions such as JP-A-2-233626 and JP-A-4-501575 have been proposed at present. Unlike the materials conventionally used with a positive relative permittivity Δε, the IPS method, VA method, and ECB method described above use a material with a negative Δε. In order to improve the display characteristics, it is required that the liquid crystal material has large negative Δε.

On the other hand, with the recent portability, a reflection type liquid crystal display device which does not use a backlight has been put into practical use. In a liquid crystal display device, in order to prevent coloring and unevenness due to the generation of interference fringes, the product of the cell thickness (d) and the refractive index anisotropy (Δn)
It is necessary to set (Δn ・ d) to a certain value (0.5, 1.0, 1.6, 2.2, usually the former two are often used), but this is when the backlight is used, In the reflective liquid crystal display element described above, the value of d is doubled because the optical path length is a round trip if the cell thickness is the same for viewing reflected light, and as a result, a value of 1/2 is required as Δn. . By reducing the cell thickness, coloring and unevenness due to the generation of interference fringes can be prevented, but there is a limit, and as a result, a liquid crystal material having a small Δn is required. However, with a composition simply replaced with a compound having a relatively small Δn, Δn cannot be sufficiently reduced, and there are problems such as deterioration of other liquid crystal characteristics described above.
Development of a new liquid crystal composition has been desired.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electro-optical display element, especially a liquid crystal display element as described above, which has a large negative ΔΔ and a low refractive index anisotropy.
It is an object of the present invention to provide a liquid crystal composition capable of maintaining a high voltage holding ratio up to a high temperature and a liquid crystal display device using the same, or to provide a liquid crystal composition and a liquid crystal display device in which the above-mentioned drawbacks are improved from the conventional ones.

[0006]

In order to solve the above problems, the present invention has found the following liquid crystal compositions as a result of examining liquid crystal compositions using various liquid crystal compounds.

General formula (I)

[Chemical 4] (In the formula, R ¹ represents an alkyl group having 1 to 10 carbon atoms or 2 to 10 carbon atoms.
Represents an alkenyl group of, which has at least one halogen which is unsubstituted or substituted, and one or two or more methylene groups present in these groups are each independently an oxygen atom. May be replaced by an oxygen atom or a sulfur atom so that they are not directly bonded to each other, or R ¹ represents a hydrogen atom and R ² has 1 to 15 carbon atoms.
Represents an alkyl group or an alkenyl group having 2 to 15 carbon atoms,
This group is unsubstituted or has at least one halogen as a substituent and is present in these groups
One or more methylene groups may each independently be replaced by an oxygen atom or a sulfur atom, as the oxygen atoms are not directly bonded to each other.

A and B are each independently (a) a 1,4-phenylene group, a 2-fluoro-1,4-phenylene group or a 2,3-difluoro-1,4-phenylene group (in this group, The existing carbon atom may be replaced by a nitrogen atom, but the nitrogen atoms are not adjacent to each other) (b) trans-1,4-cyclohexylene group (one methylene group present in this group) Or, two or more methylene groups which are not adjacent to each other may be replaced by oxygen atom and / or sulfur atom) (c) 1,4-cyclohexenylene group, 1,4-bicyclo (2.2.2)
Octylene group, piperidine-1,4-diyl group, naphthalene-
2,6-diyl group, decahydronaphthalene-2,6-diyl group and 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, wherein at least one of A or B is 2-fluoro -1,4-phenylene group, 6-fluoropyridine-2,5-diyl group or 2,3-
Represents a difluoro-1,4-phenylene group, m and n each independently represent 0, 1 or 2, but satisfy m + n ≦ 3, M and
N is independently -COO-, -OCO-, -CH ₂ O-, -OCH
_{2 -, - CH 2 CH 2} -, - CH = CH -, - C≡C -, - (CH 2) 4 -, - CH = CH-CH
₂ CH _2- , -CH ₂ CH ₂ -CH = CH- or represents a single bond, A, B, L, M
When a plurality of N and N are present, they may be the same or different. ) Containing one or more compounds represented by,

Further, the general formula (II)

[Chemical 5] (In the formula, R ³ and R ⁴ each independently represent an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms, and this group is at least one halogen which is unsubstituted or substituted. And one or more methylene groups present in these groups are each independently C, which may be replaced by an oxygen atom or a sulfur atom such that the oxygen atoms are not directly bonded to each other, D and E are each independently (a) a 1,4-phenylene group, a 2-fluoro-1,4-phenylene group or a 2,3-difluoro-1,4-phenylene group (the carbons present in this group Atoms may be replaced by nitrogen atoms, but the nitrogen atoms are not adjacent) (b) trans-1,4-cyclohexylene group (one methylene group present in this group or adjacent Not place two or more methylene groups on oxygen and / or sulfur atoms Gills which may be) (c) 1,4-cyclohexenylene group, 1,4-bicyclo (2.2.2)
Octylene group, piperidine-1,4-diyl group, naphthalene-
2,6-diyl group, 3-fluoronaphthalene-2,6-diyl group, 4
-Fluoronaphthalene-2,6-diyl group, 5-fluoronaphthalene-2,6-diyl group, 3,4-difluoronaphthalene-2,6-diyl group, 3,5-difluoronaphthalene-2,6-diyl group , 4,5
-Difluoronaphthalene-2,6-diyl group, 3,4,5-trifluoronaphthalene-2,6-diyl group, decahydronaphthalene-
2,6-diyl group and 1,2,3,4-tetrahydronaphthalene-2,6
-Diyl group, 5-fluoro-1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 7-fluoro-1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 8- Fluoro-1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 7,8-difluoro-1,2,3,
4-tetrahydronaphthalene-2,6-diyl group is represented, but C,
At least one of D or E represents a 2-fluoro-1,4-phenylene group, a 6-fluoropyridine-2,5-diyl group or a 2,3-difluoro-1,4-phenylene group, and l is 0, 1 or 2, K and P are each independently -COO-, -OCO-, -CH ₂ O-,
_{-OCH 2 -, - CH 2 CH} 2 -, - CH = CH -, - C≡C -, - (CH 2) 4 -, - CH = C
H-CH ₂ CH _2- , -CH ₂ CH ₂ -CH = CH- or represents a single bond, and E and P
When there are a plurality of, they may be the same or different. The present invention provides a liquid crystal composition containing one or more compounds represented by the formula (1) and a liquid crystal display device using the same.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An example of the present invention will be described below. The dielectric anisotropy of the liquid crystal composition of the present invention is preferably negative and has an absolute value of 1 or more, and more preferably negative and has an absolute value of 2 or more. Further, the compound of the general formula (I) 5 wt% ~ 5
Contains 0 mass%, the compound of the general formula (II) 5 mass% ~ 90 mass%
It is preferable to contain the compound of the general formula (I) at 5% by mass.
To 50% by mass, preferably 5% to 90% by mass of the compound of the general formula (II), 5% to 50% by mass of the compound of the general formula (I), the general formula (II ) Compound of 5 mass% ~ 90
Contains mass%, general formula (III)

[0011]

[Chemical 6] (In the formula, R ⁵ and R ⁶ represent an alkyl group or an alkoxyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, and an alkenyloxy group having 3 to 16 carbon atoms, and F and G are Each independently (a) 1,4-phenylene group (the carbon atoms present in this group may be replaced by nitrogen atoms, but the nitrogen atoms are not adjacent to each other) (b) trans-1, 4-cyclohexylene group (one methylene group present in this group or two or more non-adjacent methylene groups may be replaced by oxygen atom and / or sulfur atom) (c) 1,4 -Cyclohexenylene group, 1,4-bicyclo (2.2.2)
Octylene group, piperidine-1,4-diyl group, naphthalene-
2,6-diyl group, decahydronaphthalene-2,6-diyl group and 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, Q is -COO-, -OCO-, -CH ₂ O-, -OCH _2- , -CH ₂ CH _2- , -CH
= CH-, -C≡C-,-(CH ₂ ) ₄ -or a single bond, o represents 0, 1 or 2, and when Q and G are present, they may be the same or different. Is also good. More preferably, the compound (5) is contained in an amount of 5% by mass to 50% by mass.

These compounds are compounds of the general formula (I)
Contains 1 to 4 kinds, preferably 1 to 10 kinds of the compound of the general formula (II), 1 to 4 kinds of the compound of the general formula (I), the compound of the general formula (II) Containing 1 to 10 types, the general formula (II
It is more preferable to contain 1 to 10 compounds of I).

In the present invention, the compound of the general formula (I) preferably has the following embodiments.

R ¹ is preferably an alkyl group having 1 to 5 carbon atoms or a hydrogen atom, more preferably a hydrogen atom.

R ² is an alkyl group having 1 to 8 carbon atoms, 1 carbon atom
It is preferable to represent an alkoxy group having 1 to 8 carbon atoms, an alkoxyalkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms or an alkenyloxy group having 3 to 8 carbon atoms, an alkyl group having 1 to 5 carbon atoms, and a carbon number. It is more preferable to represent an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms or an alkenyloxy group having 3 to 5 carbon atoms, and in the case of an alkenyl group, the following formulas (a) to (e)
The structure of is more preferable.

[0016]

[Chemical 7] (The structural formula is assumed to be connected to the ring at the right end.) A and B
Are each independently a 1,4-phenylene group, 2-fluoro-
1,4-phenylene group, 2,3-difluoro-1,4-phenylene group, 6-fluoropyridine-2,5-diyl group or trans-1,
It is preferable to represent a 4-cyclohexylene group, and B is a 2-fluoro-1,4-phenylene group, a 6-fluoropyridine-2,5-diyl group or a 2,3-difluoro-1,4-phenylene group. It is more preferable to represent.

It is preferable that m and n each independently represent 0 or 1, and it is more preferable that m represents 1.

L, M and N are each independently --COO--, --O
CO-, -CH ₂ O-, -CH ₂ CH _2- , -C≡C- or preferably represents a single bond, and CH ₂ O-, -CH ₂ CH _2- , -C≡C- or a single bond. Is more preferably represented.

Specifically, the compounds of the general formula (I) are preferably the following compounds.

[Chemical 8] (In the formula, R ^1a represents an alkyl group having 1 to 3 carbon atoms or a hydrogen atom, R ^2a represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms. represents an alkyl group, an alkenyloxy group alkenyl group, or 3 to 5 carbon atoms having 2 to 5 carbon atoms, L is -COO -, - OCO -, - CH 2 O -, - CH 2 CH 2 -, - C
≡C- or a single bond, and X ¹ and X ² each independently represent a hydrogen atom or a fluorine atom, but at least one of X ^{1 and} X ² represents a fluorine atom. )

[0020]

[Chemical 9] (In the formula, R ^1a represents an alkyl group having 1 to 3 carbon atoms or a hydrogen atom, R ^2a represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms. represents an alkyl group, an alkenyloxy group alkenyl group, or 3 to 5 carbon atoms having 2 to 5 carbon atoms, L is -COO -, - OCO -, - CH 2 O -, - CH 2 CH 2 -, - C
≡C- or a single bond, and X ¹ and X ² each independently represent a hydrogen atom or a fluorine atom, but at least one of X ^{1 and} X ² represents a fluorine atom. )

In the present invention, the compound of the general formula (II) preferably has the following embodiments. R ³ and R ⁴ are each independently an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxyalkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, or a carbon number 3 It is preferable to represent an alkenyloxy group having 8 to 8 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms or an alkenyloxy group having 3 to 5 carbon atoms. More preferably, in the case of an alkenyl group, the structures of formulas (a) to (e) are more preferable.

C, D and E are each independently 1,4-phenylene group, 2-fluoro-1,4-phenylene group, 2,3-difluoro-1,4-phenylene group, 6-fluoropyridine- It is preferably a 2,5-diyl group or a trans-1,4-cyclohexylene group.

It is preferable that l represents 0 or 1, and when l represents 1, E represents 2-fluoro-1,4-phenylene group, 2,3-difluoro-1,4-phenylene group or 6-fluoropyridine. It is preferable to represent a -2,5-diyl group, and when l represents 0, D is 2,3-
Difluoro-1,4-phenylene group or 6-fluoropyridine-
It preferably represents a 2,5-diyl group.

K and P are independently -COO-, -OCO-,
_{-CH 2 O -, - CH 2} CH 2 -, - C≡C- or preferably represents a single _{bond, CH 2 O -, - CH} 2 CH 2 -, - C≡C- or a single bond Is more preferable.

The compounds of general formula (II) are specifically preferably the following compounds.

[Chemical 10] (In the formula, R ^3a and R ^4a are each independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkoxyalkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms. Or represents an alkenyloxy group having 3 to 5 carbon atoms, L is -COO-, -OCO
_{-, - CH 2 O -,} - CH 2 CH 2 -, - C≡C- or a single bond. )

[0026]

[Chemical 11] (In the formula, R ^3a and R ^4a are each independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkoxyalkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms. Or represents an alkenyloxy group having 3 to 5 carbon atoms, L is -COO-, -OCO
_{-, - CH 2 O -,} - CH 2 CH 2 -, - C≡C- or a single bond. In the present invention, the compound of the general formula (III) preferably has the following embodiments.

R ⁵ and R ⁶ are each independently an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, or a carbon atom. It is preferable to represent an alkenyloxy group having 3 to 8 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms or an alkenyloxy group having 3 to 5 carbon atoms. Is more preferable, and in the case of an alkenyl group, the structures of formulas (a) to (e) are more preferable.

It is preferable that F and G each independently represent a 1,4-phenylene group or a trans-1,4-cyclohexylene group.

Q is -COO-, -OCO-, -CH ₂ O-, -CH ₂ CH _2- , -C
≡C- or preferably represents a single bond, and -CH ₂ CH _2- , -C≡
More preferably it represents C- or a single bond. It is preferred that o represents 0 or 1.

Specifically, the following compounds are preferable as the compound of the general formula (III). (In the formula, R ⁵ and R ⁶ represent an alkyl group or an alkoxyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, and an alkenyloxy group having 3 to 5 carbon atoms.) In addition to the compounds described above, ordinary nematic liquid crystals, smectic liquid crystals, cholesteric liquid crystals, etc. may be contained.

The liquid crystal composition of the present invention is useful for AM-LCDs, but is particularly useful for liquid crystal display elements of IPS type, VA type, MVA type, ECB type among AM-LCDs, and is of a transmissive or reflective type. Type liquid crystal display device.

[0032]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Further, “%” in the compositions of the following Examples and Comparative Examples means “mass%”. The characteristics measured in the examples are as follows. TN-I: Nematic phase-isotropic liquid phase transition temperature (℃) Δε: Dielectric anisotropy Δn: Refractive index anisotropy

(Example 1, Comparative Example 1) Nematic liquid crystal composition shown below (Example 1)

[Chemical 12] Was prepared. In addition, as Comparative Example 1, the following liquid crystal composition was prepared.

[0034]

[Chemical 13]

Table 1 shows the results of measuring various characteristics of these liquid crystal compositions.

[Table 1] As shown in Table 1, the liquid crystal composition of Example 1 has a dielectric anisotropy equivalent to that of the composition of Comparative Example 1,
It can be seen that the refractive index anisotropy is low.

When the voltage holding ratio was measured using the composition prepared here, it showed a high value of 99% at 80 ° C., and a liquid crystal display device having excellent display characteristics could be prepared.

(Example 2, Comparative Example 2) Nematic liquid crystal composition shown below (Example 2)

[Chemical 14] Was prepared. Further, as Comparative Example 2, the following liquid crystal composition was prepared.

[0038]

[Chemical 15]

Table 1 shows the results obtained by measuring various properties of these liquid crystal compositions.

[Table 2] As shown in Table 2, the liquid crystal composition of Example 1 has a dielectric anisotropy equivalent to that of the composition of Comparative Example 1,
It can be seen that the refractive index anisotropy is low.

When the voltage holding ratio was measured using the composition prepared here, it showed a high value of 99% at 80 ° C., and a liquid crystal display device having excellent display characteristics could be prepared.

[0041]

By combining the liquid crystal materials of the present invention, a liquid crystal composition having a large negative absolute value Δε, low refractive index anisotropy and capable of maintaining a high voltage holding ratio up to a high temperature is obtained. Was given. Further, when this composition was used as a liquid crystal display element, it was excellent in reliability and excellent. This liquid crystal display is very practical as an AM-LCD of IPS, VA, ECB, etc.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09K 19/32 C09K 19/32 19/34 19/34 G02F 1/13 500 G02F 1/13 500

Claims (13)

[Claims] 1. A compound represented by the general formula (I): (In the formula, R ¹ represents an alkyl group having 1 to 10 carbon atoms or 2 to 10 carbon atoms.
Represents an alkenyl group of, which has at least one halogen which is unsubstituted or substituted, and one or two or more methylene groups present in these groups are each independently an oxygen atom. May be replaced by an oxygen atom or a sulfur atom so that they are not directly bonded to each other, or R ¹ represents a hydrogen atom and R ² has 1 to 15 carbon atoms.
Represents an alkyl group or an alkenyl group having 2 to 15 carbon atoms,
This group is unsubstituted or has at least one halogen as a substituent and is present in these groups
One or two or more methylene groups each independently may be replaced by an oxygen atom or a sulfur atom as oxygen atoms are not directly bonded to each other A and B are each independently (a) 1,4 -Phenylene group, 2-fluoro-1,4-phenylene group, or 2,3-difluoro-1,4-phenylene group (the carbon atom present in this group may be replaced by a nitrogen atom, but a nitrogen atom Are not adjacent to each other) (b) trans-1,4-cyclohexylene group (one methylene group present in this group or two or more non-adjacent methylene groups are oxygen atoms and / or sulfur (C) 1,4-cyclohexenylene group, 1,4-bicyclo (2.2.2)
Octylene group, piperidine-1,4-diyl group, naphthalene-
2,6-diyl group, decahydronaphthalene-2,6-diyl group and 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, wherein at least one of A or B is 2-fluoro -1,4-phenylene group, 6-fluoropyridine-2,5-diyl group or 2,3-
Represents a difluoro-1,4-phenylene group, m and n each independently represent 0, 1 or 2, but satisfy m + n ≦ 3, M and
N is independently -COO-, -OCO-, -CH ₂ O-, -OCH
_{2 -, - CH 2 CH 2} -, - CH = CH -, - C≡C -, - (CH 2) 4 -, - CH = CH-CH
₂ CH _2- , -CH ₂ CH ₂ -CH = CH- or represents a single bond, A, B, L, M
When a plurality of N and N are present, they may be the same or different. ) Containing one or more compounds represented by the general formula (II) (In the formula, R ³ and R ⁴ each independently represent an alkyl group having 1 to 15 carbon atoms or an alkenyl group having 2 to 15 carbon atoms, and this group is at least one halogen which is unsubstituted or substituted. And one or more methylene groups present in these groups are each independently C, which may be replaced by an oxygen atom or a sulfur atom such that the oxygen atoms are not directly bonded to each other, D and E are each independently (a) a 1,4-phenylene group, a 2-fluoro-1,4-phenylene group or a 2,3-difluoro-1,4-phenylene group (the carbons present in this group Atoms may be replaced by nitrogen atoms, but the nitrogen atoms are not adjacent) (b) trans-1,4-cyclohexylene group (one methylene group present in this group or adjacent Not place two or more methylene groups on oxygen and / or sulfur atoms Gills which may be) (c) 1,4-cyclohexenylene group, 1,4-bicyclo (2.2.2)
Octylene group, piperidine-1,4-diyl group, naphthalene-
2,6-diyl group, 3-fluoronaphthalene-2,6-diyl group, 4
-Fluoronaphthalene-2,6-diyl group, 5-fluoronaphthalene-2,6-diyl group, 3,4-difluoronaphthalene-2,6-diyl group, 3,5-difluoronaphthalene-2,6-diyl group , 4,5
-Difluoronaphthalene-2,6-diyl group, 3,4,5-trifluoronaphthalene-2,6-diyl group, decahydronaphthalene-
2,6-diyl group and 1,2,3,4-tetrahydronaphthalene-2,6
-Diyl group, 5-fluoro-1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 7-fluoro-1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 8- Fluoro-1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 7,8-difluoro-1,2,3,
4-tetrahydronaphthalene-2,6-diyl group is represented, but C,
At least one of D or E represents a 2-fluoro-1,4-phenylene group, a 6-fluoropyridine-2,5-diyl group or a 2,3-difluoro-1,4-phenylene group, and l is 0, 1 or 2, K and P are each independently -COO-, -OCO-, -CH ₂ O-,
_{-OCH 2 -, - CH 2 CH} 2 -, - CH = CH -, - C≡C -, - (CH 2) 4 -, - CH = C
H-CH ₂ CH _2- , -CH ₂ CH ₂ -CH = CH- or represents a single bond, and E and P
When there are a plurality of, they may be the same or different. (1) A liquid crystal composition containing one or more compounds represented by the formula (1). 2. The liquid crystal composition according to claim 1, wherein the dielectric anisotropy (Δε) is negative and the absolute value is 1 or more. 3. The content of the compound of general formula (I) is 5 to 50 mass.
3. The liquid crystal composition according to claim 2, wherein the content of the compound of general formula (II) is in the range of 5 to 90 mass%. 4. Containing one to four compounds of general formula (I),
4. The liquid crystal composition according to claim 3, containing 1 to 10 compounds of the general formula (II). 5. A compound represented by the general formula (III): (In the formula, R ⁵ and R ⁶ represent an alkyl group or an alkoxyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, and an alkenyloxy group having 3 to 16 carbon atoms, and F and G are Each independently (a) 1,4-phenylene group (the carbon atoms present in this group may be replaced by nitrogen atoms, but the nitrogen atoms are not adjacent to each other) (b) trans-1, 4-cyclohexylene group (one methylene group present in this group or two or more non-adjacent methylene groups may be replaced by oxygen atom and / or sulfur atom) (c) 1,4 -Cyclohexenylene group, 1,4-bicyclo (2.2.2)
Octylene group, piperidine-1,4-diyl group, naphthalene-
2,6-diyl group, decahydronaphthalene-2,6-diyl group and 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, Q is -COO-, -OCO-, -CH ₂ O-, -OCH _2- , -CH ₂ CH _2- , -CH
= CH-, -C≡C-,-(CH ₂ ) ₄ -or a single bond, o represents 0, 1 or 2, and when Q and G are present, they may be the same or different. Is also good. ) A compound represented by 1 or 2
2. The liquid crystal composition according to claim 1, containing one or more species. 6. The liquid crystal composition according to claim 5, wherein the dielectric anisotropy (Δε) is negative and the absolute value is 1 or more. 7. The content of the compound of general formula (I) is 5 to 50 mass.
%, The content of the compound of the general formula (II) is in the range of 5 to 90 mass%, the content of the compound of the general formula (III) is 5 to 5
7. The liquid crystal composition according to claim 6, which is in the range of 0 mass%. 8. Containing one to four compounds of general formula (I),
8. The liquid crystal composition according to claim 7, which contains 1 to 10 kinds of the compound of general formula (II) and 1 to 10 kinds of the compound of general formula (III). 9. In the general formula (I), R ¹ has ¹ to 5 carbon atoms.
Represents an alkyl group or a hydrogen atom, R ² is an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxyalkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms or Represents an alkenyloxy group having 3 to 8 carbon atoms, m represents 0 or 1, n represents 1, B is 1,4-phenylene group, 2-fluoro-
A 1,4-phenylene group, a 2,3-difluoro-1,4-phenylene group or a trans-1,4-cyclohexylene group 1.
9. The liquid crystal composition according to any one of 8. 10. In the general formula (II), C, D and E are each independently 1,4-phenylene group, 2-fluoro-1,4-phenylene group, 2,3-difluoro-1,4- Represents a phenylene group or trans-1,4-cyclohexylene group, in the general formula (III), F and G each independently represent a 1,4-phenylene group or trans-1,4-cyclohexylene group. Claims 1-9
The liquid crystal composition according to any one of 1. 11. A liquid crystal display device using the liquid crystal composition according to claim 1. 12. An active matrix (AM) liquid crystal display device using the liquid crystal composition according to claim 1. 13. An IPS mode or VA mode liquid crystal display device using the liquid crystal composition according to any one of claims 1 to 10.