JPH08170079A - Nematic liquid crystal composition and liquid crystal display device using the same - Google Patents

Abstract

PURPOSE: To obtain the subject composition markedly improved in crystallinity at low temperatures without impairing its quick responsiveness and high voltage retentivity, and exhibiting nematic phase over a wide temperature range, comprising specific compounds substituted with deuterium atom(s) for the H atoms(s) of the cyclohexylene rings. CONSTITUTION: This composition comprises (A) a compound selected from those of formula I (R<1> is a 2-5C straight chain alkyl) and (B) a compound selected from those of formulas II and III ((k) and (l) are each 0 or 2; (m) is 1 or 5; (n) is 3 or 5), and at least one compound selected from the compounds A and B is a compound substituted with deuterium atom(s) (D) for the H atom(s) of the 1,4-cyclohexylene rings. It is preferable that the weight ratio A/B be (15-40):(15-50). The compound substituted with D(s) for the H(s) of the 1,4- cyclohexylene rings is pref. a compound of formula IV(X<5> -X<7> are each H or D, however, at least one of them is D), and the component B is pref. a compound of formula II.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a nematic liquid crystal composition containing a liquid crystal compound having a deuterium atom, which can improve the characteristics of an electro-optical liquid crystal display material,
More specifically, a nematic liquid crystal composition having electro-optical characteristics, particularly suitable for active matrix driving, having a small leakage current, a high voltage holding ratio, and an excellent effect of expanding a nematic phase to a low temperature region, and The present invention relates to a liquid crystal display device.

[0002]

2. Description of the Related Art Liquid crystal display devices have come to be used in watches, calculators, various measuring instruments, automobile panels, word processors, electronic notebooks, printers, computers, televisions and the like. Typical liquid crystal display systems are TN (twisted nematic), STN (super twisted nematic), DS (dynamic light scattering), GH (guest / host), and FLC (ferroelectric liquid crystal). ), Etc., and the multiplex drive has been generally used instead of the conventional static drive. Recently, the TFT (Thin Film Tr) has been replaced by such a simple matrix drive.
An active matrix drive using an anistor) or MIM (Metal-Insulator-Metal) has been put to practical use.

Various characteristics are required for liquid crystal compositions in accordance with these display systems and drive systems. (1) The liquid crystal phase has a wide temperature range from low to high temperatures, and can be driven in a wide temperature range. (2) The low threshold voltage and low voltage driveability, and (3) low viscosity and high speed response are common to all liquid crystal compositions regardless of the display method or drive method. This is an important characteristic that is required.

Up to the present, no liquid crystal compound which alone satisfies such required properties is known, and at present, a liquid crystal composition having desired properties is obtained by mixing various liquid crystal compounds. .

Among these, in order to obtain a liquid crystal composition exhibiting a liquid crystal phase in a wide temperature range, a method of mixing various liquid crystal compounds having different temperature regions of the liquid crystal phase is used. When using such a technique, for example, a nematic phase of the liquid crystal composition - isotropic liquid phase transition temperature mixing ratio, the high T _NI point crystal compound when increasing (hereinafter, referred to as T _NI point.) Should be higher. However, such compounds are of a nematic phase lower limit temperature (hereinafter, referred to as T _CN point.) So is high, T _CN point inevitably resulting liquid crystal composition may cause increased, and crystallized at a low temperature deposition In many cases, the liquid crystal composition cannot be used as a practical liquid crystal composition.

From the above, when preparing a practical liquid crystal composition in which the temperature range of the nematic phase is wide from a low temperature region to a high temperature region, a liquid crystal compound having a low melting point and a nematic phase at room temperature are generally used. The temperature range of the liquid crystal phase is adjusted by empirically mixing 10 to 20 kinds of the liquid crystal compound shown and a compound having a high T _NI point.

However, at the same time as expanding the temperature range, it is necessary to optimize the electro-optical characteristics and the viscosity in accordance with the purpose of use, so that other liquid crystal compounds as constituent components of the liquid crystal composition are It cannot be used unless it satisfies various required properties to some extent, including compatibility with compounds. Therefore, of the many liquid crystal compounds, the selection range of compounds that can be used in preparing a practical liquid crystal composition is considerably limited.

For example, liquid crystal compositions for active matrix driving systems such as TFT and MIM, which are becoming the mainstream of liquid crystal display devices at present, are required to have the above-mentioned characteristics (1) to (3). In addition to the fourth characteristic, it is further required (4) to have a high voltage holding ratio. This is because when the voltage holding ratio of the liquid crystal composition is low, a flicker phenomenon occurs in which the luminance of a pixel that should have been driven changes.

In general, in order to increase the voltage holding ratio of a liquid crystal composition, it must be chemically stable against heat and light in the device and have a high specific resistance value. As a result of various investigations on liquid crystal compounds satisfying such required characteristics, among the compounds conventionally used for TN and STN, liquid crystal compounds having an ester group, a cyano group, a pyrimidine ring, a dioxane ring, or the like have a voltage holding property. It was found to be unsuitable for active matrix as it reduces the rate.

Also, in the active matrix drive system, the display system is the same as the conventional TN display system, and therefore it is essential that the dielectric anisotropy (Δε) of the liquid crystal composition is positive as a whole. However, among the conventionally used liquid crystal compounds having a positive Δε (hereinafter referred to as a p-type liquid crystal compound), those having a relatively large Δε also similarly lower the voltage holding ratio. Is not suitable for active matrix driving.

[0011]

[Chemical 4]

(In the formula, R represents an alkyl group.) Therefore, at present, in order to make Δε of the liquid crystal composition a positive and appropriate value, a compound having a fluoro group or a chloro group as a functional group, for example, Such a p-type liquid crystal compound is used as a material for an active matrix.

[0013]

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[0014]

[Chemical 6]

(In the formula, R represents an alkyl group and R'represents an alkyl group, an alkenyl group or an alkoxyalkyl group.) However, these compounds are used to achieve the electro-optical characteristics required for active matrix driving. However, since many liquid crystal compounds used for the active matrix have a relatively high T _NI point, it is very difficult to prepare a liquid crystal composition having a sufficiently low T _CN point.

In order to solve this problem, several homologues having the same skeleton and different from each other in the range of 2 to 7 carbon atoms of the terminal alkyl group are added to the above fluoro compounds. Is used to lower the T _CN point of the liquid crystal composition. However, in this method, the T _CN point does not decrease so much, and the viscosity tends to increase as the number of carbon atoms of the terminal alkyl group increases, so that the response characteristic of the above (3) is deteriorated. I will end up.

As described above, no active liquid crystal composition satisfying all of the above-mentioned characteristics (1) to (4) has been obtained so far, and the liquid crystal composition for active matrix is (2). Priority is given to satisfying the characteristics of (4) to (4), and in the temperature range of (1), even if the T _CN point is not sufficiently low, it is unavoidable to use it. Many are easy to deposit.

As described above, as the liquid crystal composition having a wide temperature range of the liquid crystal phase of the above (1),
Although it is required that the liquid crystal composition has a high T _NI point as well as a low T _CN point, in reality, even if the temperature is higher than the T _CN point, crystals will not be formed if stored in a low temperature region for a long period of time. Since a large number of materials are deposited, a highly reliable liquid crystal display device does not have crystals deposited in the liquid crystal composition for a long period of time even in a low temperature region, and there is no display defect due to environmental temperature change on the entire display screen. Required.

At the T _CN point of the liquid crystal composition, a mixed composition composed of individual liquid crystal simple substances often exhibits a supercooling phenomenon. Therefore, at the T _CN point, the liquid crystal composition is solidified with liquid nitrogen or the like. Crystallization is performed by cooling to a glass state at a sufficiently low temperature (for example, −70 ° C.), and then the transition temperature from the solid to the nematic phase is measured while gradually increasing the temperature, and this is taken as the T _CN point.

However, in the case of a practical liquid crystal composition having 10 to 20 kinds of components, since it is not a eutectic mixture,
Even if the crystal is stored at a temperature higher than the lower limit temperature of the nematic phase based on the above-described measurement, crystals are often precipitated, which eventually narrows the drivable temperature range.

For example, it is not uncommon for crystals to precipitate at room temperature even though the T _CN point is -70 ° C. In addition, as described above, it is required that a nematic phase is stably shown in a wide temperature range from -40 ° C to 110 ° C for in-vehicle use or aircraft use, but -55 ° C.
At present, no liquid crystal composition has been obtained in which crystals do not precipitate even when stored at low temperature. Therefore, even a liquid crystal composition that is actually widely used for in-vehicle use is, for example, -25 ° C.
When stored in, some crystals may precipitate in about one week.

From such an example, the T _{CN of the} liquid crystal composition is also
Even point is very low, so not necessarily from the crystals at higher temperatures it does not precipitate, as meeting the characteristics of the above (1) is not possible T _CN point is lower, the crystal even in a low temperature region No precipitation is required to obtain high reliability.

As described above, the liquid crystal composition is prepared by mixing various liquid crystal compounds so as to be adapted to the display system and the driving system. However, the liquid crystal compounds currently used alone have improved characteristics. Is limited. In particular,
A general-purpose liquid crystal composition is often designed with a focus on satisfying electro-optical characteristics. However, among such general-purpose liquid crystal compositions, particularly TF
In the liquid crystal composition for the active matrix driving system such as T and MIM and the liquid crystal composition for the STN liquid crystal display device, the temperature range of the liquid crystal phase of (1) is wide, and the crystal is formed in the low temperature region. Almost no material has high reliability in practice because it does not precipitate.

A general-purpose liquid crystal composition which substantially satisfies the above-mentioned characteristics (2) to (4) has different temperatures depending on the purpose of use, but crystals are precipitated for about one month even if stored at a relatively low temperature. If not, it is recognized as a highly reliable practical liquid crystal.

However, when such a liquid crystal composition is used, the ambient temperature at which the liquid crystal display device using it as a constituent material is naturally limited. As is clear from the above, it is a highly reliable liquid crystal composition in which crystals do not precipitate even at a lower temperature and sufficiently satisfies the electro-optical characteristics required for various display systems and drive systems. Despite the desire for liquid crystal compositions, such liquid crystal compositions have not yet been obtained.

[0026]

The problem to be solved by the present invention is that the problem of crystal precipitation in the low temperature region can be remarkably improved without impairing the high-speed response and the high voltage holding ratio. It is an object of the present invention to provide a liquid crystal composition that does not deteriorate electro-optical characteristics such as a threshold voltage, and to provide a liquid crystal display device that does not cause flicker and has excellent contrast by using this composition.

[0027]

Means for Solving the Problems The inventors of the present invention have made extensive studies in order to solve the above problems. However, there is a limit to the improvement of the characteristics as described above only with the liquid crystal compounds which are currently widely used. . Therefore, the present inventors considered that it is necessary to develop a liquid crystal material that has not been used in general-purpose liquid crystal compositions at all.

Therefore, the present inventors have paid attention to various documents, and among them, regarding the liquid crystal compound having a deuterium atom (D), there have already been reports of several examples as shown below. 1) H. Gasparoux et al., Ann.ReV.Phys.Chem., 27, 175 (1976) 2) GWGray et al., Mol.Cryst.Liq.Cryst., 41, 75 (1977) 3) AJ Leadbetter et al., J. Phys . [Paris] coll C3, 40,
125 (1979) 4) A. Kolbe et al., Z. Naturforsch., 23a, 1237 (1968) 5) JDRowell et al., J. Chem. Phys., 43, 3442 (1965) 6) WDPhilips et al., J. Chem. Phys. ., 41, 2551 (1964) 7) AFMartins et al., Mol. Cryst. Liq. Cryst., 14, 85 (197
1) 8) ET Samulski et al., Phys. Rev. Lett., 29, 340 (1972) 9) H. Zimmermann et al., Liquid Crystals., 4, 591 (1989)

However, in these reports, 4
-Example of replacing hydrogen atom (H) in carboxyl group of alkoxyalkoxybenzoic acid with deuterium atom (D) (Reference (1))
In all the examples except the above, the hydrogen atom (H) in the terminal group was replaced with a deuterium atom (D), or the hydrogen atom (H) bonded to the benzene ring was replaced with a deuterium atom (D). . Moreover, none of these documents describes an example in which the compound is added to a liquid crystal composition.

Therefore, the present inventors have not reported a hydrogen atom (H) bonded to a saturated hydrocarbon ring, which has not been reported so far.
Was attempted to be replaced by a deuterium atom (D), but it was revealed that the liquid crystal material obtained thereby had excellent properties that could not be predicted at all from the aforementioned literature. .

That is, the present invention has the general formula (I) in order to solve the above problems.

[0032]

[Chemical 7]

(In the formula, R ¹ represents a linear alkyl group having 2 to 5 carbon atoms), and the first compound group represented by the formula (2) and the general formulas (II) and (III).

[0034]

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(Wherein, k and l each independently represent an integer of 0 or 2, m represents an integer of 1 or 5, and n
Represents an integer of 3 or 5. ) Containing a compound selected from the second group of compounds, and at least one of the compounds selected from the two groups is 1,4
-A nematic liquid crystal composition, which is a compound in which at least one hydrogen atom (H) of a cyclohexylene group is substituted with a deuterium atom (D).

The present invention also provides an active matrix liquid crystal display device, twisted nematic or super twisted nematic liquid crystal device using the above liquid crystal composition.

The present invention will be described in more detail below. A compound represented by the above general formulas (I), (II) and (III), in which at least one hydrogen atom (H) of a 1,4-cyclohexylene group is replaced with a deuterium atom (D), A typical example is shown below. In addition, in these compounds, a compound represented by the formula (b-1)

[0038]

[Chemical 9]

The cyclohexane ring represented by means that it has a deuterium atom (D) with a probability corresponding to the abundance ratio to the naturally existing hydrogen atom having a mass number of 1, and the formula (b)
-2)

[0040]

[Chemical 10]

The cyclohexane ring represented by means that it has a deuterium atom (D) at the position indicated by D with a probability significantly different from the ratio existing in nature. Hereinafter, in the present invention, these two cyclohexane rings are used with the same definition.

[0042]

[Chemical 11]

(In the formula, R ¹ , k, l, m and n have the same meanings as described above.) The nematic liquid crystal composition of the present invention is characterized by the general formula (I).
And a compound selected from the compounds of the second group represented by the general formulas (II) and (III).

The compound group represented by the general formula (I) has a 3,4-difluorophenyl group in the molecular structure, exhibits the effect of reducing the threshold voltage, and exhibits sufficiently high voltage holding characteristics. , And also has excellent compatibility with other compounds,
In particular, it exhibits the effect of inducing and expanding the nematic phase on the low temperature side.

The compounds represented by the general formulas (II) and (III) are those capable of optimizing the birefringence (Δn) and preparing a nematic liquid crystal composition in which the contrast characteristic of liquid crystal display is emphasized. Further, it has the effect of reducing the viscosity of the nematic liquid crystal composition and improving the response characteristics. However, with a composition consisting of only the compounds represented by the general formulas (II) and (III), the temperature range of the nematic phase is very narrow, and it is difficult to prepare a nematic liquid crystal composition that can be driven from room temperature to low temperature. It was However, by using the compound represented by the above general formula (I), the compound can be driven in a wide temperature range, high-speed response, without impairing the excellent characteristics of each compound,
It is possible to obtain a nematic liquid crystal composition having excellent high voltage holding characteristics.

As a second feature, at least one of the compounds selected from these two groups has at least one hydrogen atom (H) on the cyclohexane ring substituted with a deuterium atom (D). In addition to the excellent electro-optical characteristics as described above, the crystallinity at low temperature can be improved by containing such a compound. Especially when stored in the low temperature range,
It has a feature that nematic liquid crystallinity can be maintained for a long time.

Such an example is shown below. Liquid crystal composition of the present invention (3-1)

[0048]

[Chemical 12]

The properties of this composition were as follows. T _NI : 95.0 ° C. T → _N : −21 ° C. V _th : 2.50 V Δε: 2.9 Δn: 0.079 τr = τd: 21.0 msec In contrast, a deuterium-substituted compound is contained. Liquid crystal composition (a) other than the present invention

[0050]

[Chemical 13]

The properties of this composition were as follows. T _NI : 95.4 ° C. T → _N : −6 ° C. V _th : 2.61 V Δε: 2.7 Δn: 0.081 τr = τd: 23.0 msec From the above, the deuterium-substituted compound can be obtained. The contained liquid crystal composition of the present invention has a large decrease in T → _N and almost no change in T _NI . Therefore, in the nematic liquid crystal composition of the present invention, the nematic phase is expanded to the low temperature side, the crystallinity at low temperature is remarkably improved, and most of the electro-optical characteristics are retained. Therefore, it is extremely useful as a liquid crystal composition for active matrix and can be used particularly in a low temperature region.

The nematic liquid crystal composition of the present invention preferably contains a compound of the general formula (II), especially as a compound selected from the second group. Furthermore, as the compound having a deuterium atom (D), a compound represented by the general formula (Ia)

[0053]

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(In the formula, R ¹ represents a linear alkyl group having 2 to 5 carbon atoms, and X ^{1 to} X ⁴ each independently represent a hydrogen atom (H) or a deuterium atom (D). , At least one of which represents a deuterium atom (D), or a compound represented by the general formula (Ib):

[0055]

[Chemical 15]

(In the formula, R ¹ represents a linear alkyl group having 2 to 5 carbon atoms, and X ^{5 to} X ⁷ each independently represent a hydrogen atom (H) or a deuterium atom (D). However, a compound represented by at least one of them represents a deuterium atom (D) is preferable.

The compound represented by the general formula (I) is preferably contained in the range of 10 to 50% by weight.
The range of 5 to 40% by weight is more preferable. Further, it is preferable to contain the compound of the second group in the range of 10 to 50% by weight, more preferably the range of 15 to 50% by weight.

The nematic liquid crystal composition of the present invention thus obtained has a nematic phase-isotropic liquid transition temperature (T _NI ) of around 95 ° C., as shown in Examples below.
Crystal phase or smectic phase-nematic phase transition temperature (T
→ _N ) showed a nematic phase at a wide temperature of −20 ° C. or lower, and a characteristic showing a response of 10 to 20 msec could be obtained.

The nematic liquid crystal composition of the present invention is
When the heating acceleration test and the ultraviolet irradiation acceleration test shown in Examples described later were carried out, it has a high voltage holding ratio of 98% or more even after each acceleration test, and is chemically stable and has a high resistance value. It was confirmed.

[0060]

The present invention will be described in detail below with reference to examples.
The present invention is not limited to these examples. In the examples, the meanings of the symbols of the measured characteristics are as follows.

T _NI : nematic phase-isotropic liquid phase transition temperature (° C.) T → _N : crystalline phase or smectic phase-nematic phase transition temperature (° C.) V _th : TN-LCD having a panel liquid crystal layer thickness of 6 μm Threshold voltage (V) Δε: dielectric anisotropy Δn: birefringence τr = τd: rise time τr from no voltage applied to light transmission and voltage Response time (msec) when the falling time τd is equal when the voltage is removed from the applied state until light is no longer transmitted (msec). Further, the accelerated test of the composition is to put 2 g of the liquid crystal composition into an ampoule tube, and after vacuum degassing The sample was subjected to nitrogen substitution treatment, sealed, and subjected to a heating acceleration test at 180 ° C. for 1 hour, and an ultraviolet irradiation acceleration test “SUNTEST” (manufactured by Original Hanau) for 10 hours. The specific resistance and voltage holding ratio of the liquid crystal composition were measured before and after the accelerated test. (Example 1)

[0062]

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A nematic liquid crystal composition (3-1) consisting of
Was prepared and various properties of this composition were measured. The results were as follows. T _NI : 95.0 ° C. T → _N : −21 ° C. V _th : 2.50 V Δε: 2.9 Δn: 0.079 τr = τd: 21.0 msec Specific resistance before test: 8.9 × 10 ¹³ Ω・ Cm Specific resistance after heating accelerated test: 5.8 × 10 ¹³ Ω ・ cm Specific resistance after ultraviolet irradiation accelerated test: 3.8 × 10 ¹³ Ω ・ cm Voltage holding ratio before test: 99.8% (measurement temperature 80 C.) Voltage holding ratio after heating accelerated test: 99.0% (measurement temperature 80 ° C.) Voltage holding ratio after ultraviolet irradiation accelerated test: 98.9% (measurement temperature 80 ° C.) This nematic liquid crystal composition (3-1) When an active matrix liquid crystal display device as a constituent material was manufactured, it was confirmed that the leakage current was small and flicker did not occur.

Further, this nematic liquid crystal composition (3-
A chiral substance "S-811" (manufactured by Merck) was added to 1) to prepare a mixed liquid crystal. On the other hand, an organic film of "SAN EVER 150" (manufactured by Nissan Kagaku Co., Ltd.) was rubbed on the opposing flat transparent electrodes to form an alignment film, and an STN-LCD display cell with a twist angle of 220 degrees was produced. The above-mentioned mixed liquid crystal was injected into this cell to construct a liquid crystal display device, and display characteristics were measured. As a result, a liquid crystal display device having an STN-LCD display characteristic with a low threshold voltage, excellent high time division characteristics, and improved display screen flicker and crosstalk phenomenon was obtained. (Example 2)

[0065]

[Chemical 17]

A nematic liquid crystal composition (3-2) consisting of
Was prepared and various properties of this composition were measured. The results were as follows. T _NI : 91.5 ° C. T → _N : −10 ° C. V _th : 2.73 V Δε: 2.3 Δn: 0.074 τr = τd: 14.0 msec A chiral substance in this nematic liquid crystal composition (3-2). "S-811" (manufactured by Merck) was added to prepare a mixed liquid crystal. On the other hand, an organic film of "SAN EVER 150" (manufactured by Nissan Kagaku Co., Ltd.) was rubbed on the opposing flat transparent electrodes to form an alignment film, and an STN-LCD display cell with a twist angle of 220 degrees was produced. The above-mentioned mixed liquid crystal was injected into this cell to construct a liquid crystal display device, and display characteristics were measured. As a result, STN- with a low threshold voltage, excellent high time division characteristics, and improved display screen flicker and crosstalk phenomenon.
A liquid crystal display device having LCD display characteristics was obtained. (Comparative Example 1)

[0067]

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A nematic liquid crystal composition (a) consisting of was prepared and various properties of this composition were measured. The results were as follows. T _NI : 95.4 ° C. T → _N : −6 ° C. V _th : 2.61 V Δε: 2.7 Δn: 0.081 τr = τd: 23.0 msec (Example 3)

[0069]

[Chemical 19]

A nematic liquid crystal composition (3-3) consisting of
Was prepared and various properties of this composition were measured. The results were as follows. T _NI : 95.2 ° C. T → _N : −20 ° C. V _th : 2.79 V Δε: 2.37 Δn: 0.067 τr = τd: 11.0 msec

[0071]

INDUSTRIAL APPLICABILITY The nematic liquid crystal composition of the present invention exhibits a nematic phase in a wide temperature range, its crystallinity at a low temperature is remarkably improved, and it has a high speed response and a high voltage holding ratio. Therefore, the liquid crystal display device of the present invention using this,
It is possible to improve the flicker and crosstalk phenomenon of the display screen, and obtain good driving characteristics and display characteristics in the TN-LCD, STN-LCD or the active matrix system which has a large amount of information.

Claims (8)

[Claims] 1. A general formula (I): (In the formula, R ¹ represents a straight-chain alkyl group having 2 to 5 carbon atoms.) And (2) the general formulas (II) and (III) (Wherein k and l each independently represent an integer of 0 or 2, m represents an integer of 1 or 5, and n represents an integer of 3 or 5). Containing at least one compound selected from the two groups, wherein at least one hydrogen atom (H) of the 1,4-cyclohexylene group is a deuterium atom (D). A nematic liquid crystal composition, which is a compound substituted with. 2. The nematic liquid crystal composition according to claim 1, wherein the compound selected from the second group is a compound represented by the general formula (II). 3. The nematic liquid crystal composition according to claim 1, wherein the compound selected from the second group is a compound represented by the general formula (III). 4. A compound obtained by substituting at least one hydrogen atom (H) of a 1,4-cyclohexylene group with a deuterium atom (D) has the general formula (1-a) or (1-b): Chemical 3] (In the formula, each R ¹ independently represents a linear alkyl group having 2 to 5 carbon atoms, and X ^{1 to} X ⁷ each independently represent a hydrogen atom (H) or a deuterium atom (D). But X ¹
At least one of X ⁴ and X ^{5 to} X ⁷ represents a deuterium atom (D). 4. The nematic liquid crystal composition according to claim 1, which is a compound represented by the formula (1). 5. A compound represented by the general formula (I)
The nematic liquid crystal composition according to claim 1, wherein the nematic liquid crystal composition is contained in an amount of -50% by weight. 6. A compound selected from the second compound group is 1
The nematic liquid crystal composition according to claim 1, 2 or 3, wherein the nematic liquid crystal composition is contained in an amount of 0 to 50% by weight. 7. An active matrix type liquid crystal display device using the nematic liquid crystal composition according to claim 1. 8. A twisted nematic or super twisted nematic liquid crystal display device using the nematic liquid crystal composition according to claim 1.