JPH1053562A - Optically active compound and antiferroelectric liquid crystal composition containing the compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject new compound exhibiting an antiferroelectric phase over a wide temperature range, having quick response at low temperature and giving excellent displaying image quality. SOLUTION: This compound is expressed by the formula ((m) is 4-12; (n) is 3-8; one of X and Y is H and the other is F; C* is asymmetric carbon), e.g. (+)-4-(1-methylhexyloxy)phenyl 4-decanoyloxy-2-fluorobenzoate. The objective optically active compound of the formula having high displaying image quality can be produced e.g. by cooling R-(-)-2-heptanol and pyridine, adding p- toluenesulfonyl chloride to the cooled mixture to obtain (+)-p-toluenesulfonic acid (1-methyl)hexyl ester as the reaction product, adding hydroquinone monobenzyl ether to the product, carrying out the hydrogen substitution reaction of the reaction product in the presence of a catalyst, adding thionyl chloride and refluxing the mixture under heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel optically active compound,
The present invention relates to an antiferroelectric liquid crystal composition containing the composition and a liquid crystal display device using the same.

[0002]

2. Description of the Related Art Liquid crystal display elements have been developed as attractive display elements to date due to their low voltage operation, low power consumption, and thin display. Furthermore, recently, liquid crystal display devices have been applied in the field of information, OA-related equipment, or television in earnest,
It is being used for various other purposes. For these reasons, liquid crystal display devices are being vigorously developed to realize higher performance large liquid crystal display devices having display capacity and display quality higher than conventional CRT display devices.

However, as long as the current nematic liquid crystal is used, the size and cost of the active matrix driven liquid crystal display element used for the liquid crystal television cannot be reduced due to the complexity of the manufacturing process and the low yield. It's not easy. Also, the simple matrix drive S
Even with a TN-type liquid crystal display element, large-capacity driving is not always easy, and the response time is limited, making it difficult to display moving images. Further, a narrow viewing angle of a display element using a nematic liquid crystal has become a serious problem. Therefore, the nematic liquid crystal display element cannot satisfy the demand for the above-mentioned high performance large liquid crystal display element.

In such a situation, a liquid crystal display element using a ferroelectric liquid crystal has attracted attention as a high-speed liquid crystal display element. The surface-stabilized ferroelectric liquid crystal (SSFLC) device announced by Clark and Lagabar has been noted for its unprecedented fast response speed and wide viewing angle, and its switching characteristics have been studied in detail. Many ferroelectric liquid crystals have been synthesized in order to optimize various physical constants. However, the threshold characteristics are insufficient, the layer structure has a chevron structure, the contrast is poor, the high-speed response has not been realized, the alignment control is difficult, and one of the biggest features of SSFLC is There are problems that it is not easy to realize bistability, which is one of them, and that the orientation is destroyed by mechanical shock and it is difficult to recover it.
Practical application requires overcoming these problems.

[0005] Apart from this, the development of elements having a switching mechanism different from that of SSFLC is also proceeding at the same time. Switching between the three stable states of a liquid crystal material having an antiferroelectric phase (hereinafter referred to as an antiferroelectric liquid crystal material) is one of these new switching mechanisms (Japanese Journal of A).
pplied Physics, Vol. 27, pp. L729, (1988)). The antiferroelectric liquid crystal device has three stable states. That is,
Two uniform states found in ferroelectric liquid crystal devices
(Ur, Ul) and the third state. Chandani et al. Report that this third state is an antiferroelectric phase (Japanese Jo
urnal of Applied Physics, Vol. 28, pp. L1261, (198
9), pp. L1265, (1989)).

[0006] Such switching between the three stable states is the first feature of the antiferroelectric liquid crystal device. A second feature of the antiferroelectric liquid crystal element is that there is a clear threshold value for an applied voltage. Further, it has a memory property, which is the third feature of the antiferroelectric liquid crystal element. By utilizing these excellent features, a liquid crystal display device having a high response speed and good contrast can be realized. Another major feature is that the layer structure is easily switched by an electric field (Japan
ese Journal of Applied Physics, Vol.28, pp.L119, (1
989), Vol. 29, pp. L111, (1990)).

This makes it possible to manufacture a liquid crystal display element having very few defects and capable of self-repairing the alignment, thereby realizing a liquid crystal element having excellent contrast. Furthermore, it has been demonstrated that voltage gradation that is almost impossible with ferroelectric liquid crystal is possible with antiferroelectric liquid crystal, opening the way to full color, and the importance of antiferroelectric liquid crystal is further increasing. (The 4th International Conference on Ferroelectric Liquid Crystals, 77
P. (1993)). As described above, the superiority of the antiferroelectric liquid crystal is becoming certain, but the driving temperature range is expanded, the response speed is further improved, and the antiferroelectric liquid crystal in which the smectic A phase is present is present. The development of liquid crystals is desired.

[0008] Regarding the response speed, a problem is particularly serious on the low temperature side below room temperature. At present, the response speed at a low temperature side, for example, at 10 ° C., is 10 to 20 times slower than that at room temperature. Therefore, in order to facilitate the driving on the low temperature side, a method of changing the frequency or the driving voltage, a method of installing a heater, and the like have been considered.
However, there are limits to changing the frequency and voltage.
It has not been possible to sufficiently cover the low properties of the liquid crystal by changing the voltage. When a heater is provided, the light transmittance of the element is reduced, resulting in a decrease in contrast and an element having a high display quality cannot be obtained.

Here, in the case of the antiferroelectric liquid crystal, there are two switching operations from the antiferroelectric state to the ferroelectric state and from the ferroelectric state to the antiferroelectric state. The two switching speeds by this voltage, ie, the response speed, are important factors that determine the display quality of the display element. The response speed from the antiferroelectric state to the ferroelectric state (hereinafter referred to as “response speed I”) is
For example, in a simple matrix drive for line-sequential scanning,
Since the writing speed per scanning line is obtained, it is important to determine the number of scanning lines constituting one screen. As the response speed I increases, the number of scanning lines can be increased, and a high-definition element can be realized.

[0010] The response speed from the ferroelectric state to the antiferroelectric state (hereinafter referred to as "response speed II") varies depending on the design of the element driving method. For example, it changes depending on the set voltage of the offset voltage. However, if the response speed II is too fast, the ferroelectric state cannot be maintained (maintaining the bright or dark state). Conversely, if the response speed II is too slow, the ferroelectric state changes to the antiferroelectric state (bright or dark). Is not rewritten from the dark state to the dark or bright state), which is inconvenient. That is, the response speed II is set to an optimal value after the driving method is determined. As described above, in order to realize a high-definition element, it is important that the response speed I is fast, and it is desirable that the response speed be less dependent on temperature.

[0011]

In practice, the antiferroelectric liquid crystal has a higher response speed on the low temperature side, a wider temperature range of the antiferroelectric phase, and a better smectic A phase, as described above. It is desirable to be present. Response speed is M. Nakag
According to awa, antiferroelectric liquid crystals have been shown to depend on the rotational viscosity of liquid crystal molecules (Masahiro Nakagawa,
Japanese Journal of Applied Physics, 30, 1759, (199
1)). That is, the lower the viscosity, the faster the response speed.

Looking at the change in the response speed with respect to temperature, the response speed decreases exponentially at temperatures below room temperature and below. The antiferroelectric liquid crystal is considered to have a high viscosity because the liquid crystal phase is a smectic phase, so that the viscosity increases rapidly at the low temperature side and the response speed decreases rapidly due to the viscous resistance. ing. One of the concrete measures to solve this problem is to add a relatively low-viscosity compound to the liquid crystal composition to lower the viscosity of the entire composition and thereby improve the response speed. Can be Although this method seems to be the most realistic solution at present, this method tends to lower the maximum temperature of the antiferroelectric phase, and although the response speed is improved, the antiferroelectric phase is improved. A problem arises in terms of the temperature range.

In general, when considering an antiferroelectric liquid crystal device as a display, it is considered that the temperature of the device becomes at least about 40 ° C. due to the backlight. Therefore, the upper limit temperature of the antiferroelectric phase needs to be at least 40 ° C. or higher for normal operation of the device. It is desirable that a smectic A phase exists on the high temperature side of this temperature in order to obtain good orientation. On the low-temperature side, it is necessary that the element can be driven at least at 10 ° C. Therefore, the lower limit temperature of the antiferroelectric phase is desirably at least 0 ° C.

[0014]

DISCLOSURE OF THE INVENTION The present invention has been made from such a viewpoint, and provides a novel optically active compound, wherein the optically active compound is one or more of specific antiferroelectric liquid crystal compounds. It has been found that an antiferroelectric liquid crystal composition that can secure an antiferroelectric phase over a wide temperature range and that responds quickly at a low temperature can be obtained by adding it to a mixture of two or more kinds, thereby completing the present invention. . That is, the present invention provides an optically active compound represented by the following general formula (1), and the compound as one or a mixture of two or more antiferroelectric liquid crystal compounds represented by the following general formula (2). An antiferroelectric liquid crystal composition obtained by mixing.

[0015]

Embedded image (In the general formula (1), m is an integer of 4 to 12, n is an integer of 3 to 8,
X and Y each represent a hydrogen atom or one of them represents a hydrogen atom and the other represents a fluorine atom, and C * represents an asymmetric carbon. In the general formula (2), R represents a linear alkyl group having 6 to 12 carbon atoms, Z represents a hydrogen atom or a fluorine atom, A represents CH ₃ or CF ₃ , r represents 0 or 1, and A represents CH ₃ . When r is 0, p is an integer of 4 to 10,
When A is CF ₃ , r is 1, s is an integer of 5 to 8, and p is 2
Or 4, and C * represents an asymmetric carbon. )

In the present invention, as the optically active compound of the general formula (1), those wherein m is 6 to 12 and n is 3 to 7 are preferred. Further, as the antiferroelectric liquid crystal compound represented by the general formula (2), those in which R has 6 to 10 carbon atoms, Z is an F atom, and p is 2 are preferable. In the antiferroelectric liquid crystal composition of the present invention, it is practical to mix the optically active compound represented by the general formula (1) in an amount of 5 to 40 mol%, more preferably 10 to 30 mol% of the composition. It is preferable that the upper limit temperature of the antiferroelectric phase is 40 ° C. or higher, the lower limit temperature is 0 ° C. or lower, and the smectic A phase is on the higher temperature side than the antiferroelectric phase. The antiferroelectric liquid crystal composition of the present invention is preferably used as a simple matrix liquid crystal display device by sandwiching it between substrates in which scanning electrodes and signal electrodes are arranged in a matrix, and the liquid crystal display device is driven by a voltage. Is performed by switching between one antiferroelectric state, two ferroelectric states, and an intermediate state therebetween.

The antiferroelectric liquid crystal compound represented by the general formula (2) used in the present invention can be produced by the method shown by the present inventors (JP-A-4-198155).
For example, it is manufactured by the following method. (B) AcO-Ph (Z) -COOH + SOCl ₂ → AcO-Ph (Z) -COCl (b) (b) + HOC * HA ((CH ₂ ) _s O) _r C _p H _{2p + 1} → AcO -Ph (Z) -COOC * HA ((CH ₂ ) _s O) _r C _p H _{2p + 1} (c) (b) + Ph-CH ₂ NH ₂ → HO-Ph (Z) -COOC * HA (( CH ₂ ) _s O) _r C _p H _{2p + 1} (d) RO-Ph-Ph-COOH + SOCl ₂ → RO-Ph-Ph-COCl (e) (c) + (d) → antiferroelectric liquid crystal In the formula, Ac is an acetyl group, Ph (Z) is a 1,4-phenylene group optionally substituted with fluorine at the 3-position, -Ph- is a 1,4-phenylene group, Ph- is a phenyl group, and R is A straight-chain alkyl group, C * indicates an asymmetric carbon.

The above manufacturing method will be briefly described below. (A) is a chlorination reaction of fluorine-substituted or unsubstituted p-acetoxybenzoic acid with thionyl chloride.
(B) is esterification by the reaction of a chlorinated product (a) with an alcohol. (C) shows the deacetylation of the ester (b). (D) is a chlorination reaction of alkyloxybiphenylcarboxylic acid. (E) is phenol (c) and chlorinated product
And (d) the formation of liquid crystal by the reaction.

[0019]

According to the present invention, a novel optically active compound and an antiferroelectric liquid crystal composition containing the same can be provided. The novel antiferroelectric liquid crystal composition provided by the present invention has an antiferroelectric phase over a wide temperature range and exhibits a high-speed response at a temperature lower than room temperature, and therefore has a high display quality. Liquid crystal display element can be realized.

[0020]

Next, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is of course not limited thereto. Example 1 (Equation (1): m = 9, X = H, Y = F, n = 5 (E1))
Preparation of (+)-4- (1-methylhexyloxy) phenyl 4-decanoyloxy-2-fluorobenzoate.

(1) Production of (1-methyl) hexyl (+)-p-toluenesulfonic acid. In a reaction vessel, 3.48 g of R-(-)-2-heptanol and pyridine 1
5 ml (milliliter) was added and cooled to -20 ° C. While stirring, 6.3 g of p-toluenesulfonyl chloride was added at once, and the mixture was stirred at this temperature for 30 minutes, and then continued at room temperature for 4 hours. The reaction mixture was poured into ice water and extracted with dichloromethane. After washing the organic phase with water, the organic phase was dried over anhydrous sodium sulfate. The solvent was distilled off, 6 g (74% yield)
Was obtained.

(2) Production of (+)-4-benzyloxyphenyl (1-methyl) hexyl ether. In the reaction vessel, (+)-p-toluenesulfonic acid prepared in (1)
(1-methyl) hexyl 6 g, hydroquinone monobenzyl ether 4.47 g, potassium hydroxide 2.38 g and ethanol
28 ml was added and the mixture was stirred at room temperature for 2 hours. Then one more
Heated to reflux for an hour. The reaction mixture was poured into water and extracted with dichloromethane. The organic layer was washed with 1N hydrochloric acid and water, and then the organic phase was dried over anhydrous sodium sulfate. The solvent was distilled off, and the crude product was purified by silica gel column chromatography (eluent; hexane / ethyl acetate = 925/75) 9 to obtain 14.9 g.
(Yield 67%) was obtained.

(3) Production of (+)-4- (1-methylhexyloxy) phenol. After putting 0.2 g of 10% palladium carbon catalyst in the reaction vessel,
The system was replaced with nitrogen. In this, (+)-4-benzyloxyphenyl (1-methyl) hexyl ether prepared in (2)
4.46 g and 30 ml of ethanol were added, and the system was replaced with hydrogen. The reaction was carried out for 8 hours while supplying hydrogen from the gas burette. After purging the system with nitrogen, the catalyst was filtered off and the solvent was distilled off to obtain 3 g (yield 97%) of the desired product.

(4) Preparation of (+)-4- (1-methylhexyloxy) phenyl 2-fluoro-4-decanoyloxybenzoate. In a reaction vessel, add 2-fluoro-4-decanoyloxybenzoic acid
1.04 g and thionyl chloride (20 ml) were added, and the mixture was heated under reflux for 4 hours. Excess thionyl chloride was distilled off under reduced pressure. The reaction solution was dissolved in toluene and washed with hydrochloric acid, an aqueous solution of sodium hydroxide, and water. The solvent was distilled off, and the obtained crude product was purified by silica gel chromatography (eluent; hexane / ethyl acetate = 94/6). The yield was 0.63 g (61% yield).

Embodiment 2 (Equation (1): m = 9, X = H, Y = F, n
= 3 (E2)) (+)-4- (1-Methylbutyloxy) phenyl = 4-decanoyloxy-2-fluorobenzoate. Example 3 (Equation (1): m = 9, X = H, Y = F, n = 7 (E3))
Production of (+)-4- (1-methyloctyloxy) phenyl 4-decanoyloxy-2-fluorobenzoate. In Example 1, instead of R-(-)-2-heptanol,
The desired product was obtained according to Example 1, except that R-(-)-2-pentanol (Example 2) or R-(-)-2-nonanol (Example 3) was used.

Embodiment 4 (Equation (1): m = 9, X = H, Y = H, n
= 5 (E4)) (+)-4- (1-Methylhexyloxy) phenyl = 4-decanoyloxy-2-fluorobenzoate. Example 5 (Equation (1): m = 10, X = H, Y = H, n = 5 (E5))
Preparation of (+)-4- (1-methylhexyloxy) phenyl 4-undecanoyloxybenzoate. In Example 1, 4-decanoyloxybenzoic acid (Example 4) or 4-undecanoyloxybenzoic acid (Example 5) was used in place of 2-fluoro-4-decanoyloxybenzoic acid. Was obtained in the same manner as in Example 1.

Embodiment 6 (Equation (1): m = 6, X = H, Y = F, n
= 5 (E6)) Preparation of (+)-4- (1-methylhexyloxy) phenyl = 4-heptanoyloxy-2-fluorobenzoate. Example 7 (Equation (1): m = 9, X = F, Y = H, n = 5 (E7))
Production of (+)-4- (1-methylhexyloxy) phenyl 4-decanoyloxy-3-fluorobenzoate. In Example 1, 2-fluoro-4-heptanoyloxybenzoic acid (Example 6) or 3-fluoro-4-decanoyloxybenzoic acid (implemented in place of 2-fluoro-4-decanoyloxybenzoic acid) A target product was obtained in the same manner as in Example 1 except that Example 7) was used.

The NMR spectrum data of the target compound obtained in Examples 1 to 7 are shown in Table 1 below. The results of identification of the liquid crystal phase by texture observation and DSC (differential scanning calorimetry) are shown in Table 2.

[0029]

[Table 1] Compound hydrogen atom code (δ, ppm) Symbol 1 2 3 4 5 6 7 Phase series E1 (δ, ppm) 2.6 7.0 7.0 8.2 7.2 6.9 4.3 I (22) SA (-9) Cr E2 2.6 7.0 7.0 8.2 7.2 6.9 4.4 I (22) SA (-1) Cr E3 2.6 7.0 7.0 8.2 7.2 6.9 4.4 I (20) SA (-7) Cr E4 2.6 7.3 8.2-7.1 6.9 4.4 I (27) SA (17) Cr E5 2.6 7.3 8.2-7.1 6.9 4.4 I (30) SA (22) Cr E6 2.6 7.0 7.0 8.1 7.1 6.9 4.4 I (9) Cr E7 2.6 8.0 7.2 8.0 7.1 6.9 4.3 I (8.8) Cr The numbers in the parentheses indicate the phase transition temperature (unit: ° C.), I indicates the isotropic phase, SA indicates the smectic A phase, and Cr indicates the crystalline phase.

[0030]

Embedded image

Examples 8 to 16 Antiferroelectric liquid crystals (2A, 2B, 2C) represented by the following chemical structural formulas
Next, the optically active compounds (E1, E4
-E7) was mixed in the amounts shown in Table 3 to prepare an antiferroelectric liquid crystal composition. Table 3 shows the results of identification of the liquid crystal phase and measurement of the response time. The same applies to antiferroelectric liquid crystals (2A, 2B, 2C). 2A; C ₉ H ₁₉ -O-Ph-Ph-COO-Ph (3F) -COO-C * H (CF ₃ ) (CH ₂ ) ₅ 0C ₂ H ₅ 2B; C ₈ H ₁₇ -O-Ph-Ph -COO-Ph (3F) -COO- C * H (CF 3) (CH 2) 5 0C 2 H 5 2C; C 8 H 17 -O-Ph-Ph-COO-Ph (3F) -COO-C * H (CH ₃ ) C ₅ H _{11 In the} formula, Ph represents a 1,4-phenylene group, Ph (3F) represents a 1,4-phenylene group substituted with fluorine at the 3-position, and C * represents an asymmetric carbon.

The phases of the antiferroelectric liquid crystal composition were identified by texture observation and DSC (differential scanning calorimetry).
In addition, the response time was measured as follows. A liquid crystal cell (cell thickness 1.8 μm) with an ITO electrode having a rubbed polyimide thin film was filled with the composition in an isotropic phase. The cell was slowly cooled at 1 ° C./min to smectic A (SA
Phase) to align the liquid crystal. The cell was placed between orthogonal polarizing plates so that the liquid crystal layer direction was parallel to the analyzer or polarizer. When the transmitted light intensity is 0% at the minimum and 100% at the maximum, a step voltage of 10Hz and 50V is applied to the liquid crystal cell, and the transmitted light changes by 10% when switching from the antiferroelectric state to the ferroelectric state. The response time is the time required to change from 90% to 90% (response speed I), and the time required for the change in transmitted light to change from 90% to 10% (response speed II) when switching from ferroelectric state to antiferroelectric state. By definition, response times were measured. All the measurement temperatures were performed at 10 ° C.

[0033]

[Table 2] Example composition Response time No component Molar ratio Phase sequence I II 82 A / E1 = 90/10 I (77) SA (67) SCA * (<-10) Cr 70 58 200 9 2A / E1 = 80/20 I (75) SA (59) SCA * (<-10) Cr 49 72400 10 2A / E1 = 70/30 I (72) SA (52) SCA * (<-10) Cr 40 74500 11 2A / E4 = 70/30 I (75) SA (57) SCA * (<-10) Cr 47 69000 12 2A / E5 = 77/23 I (75) SA (52) SCA * (<-10) Cr 45 13 100 13 2A / E6 = 70/30 I (75) SA (51) SCA * (<-50) Cr 39 2600 14 2A / E7 = 70/30 I (69) SA (53) SC * (50) SCA * (< -50) Cr 62 5400 15 2B / E6 = 70/30 I (81) SA (55) SCA * (<-20) Cr 44 920 16 2A / 2C / E1 = 56/24/20 I (92) SA ( 73) SC * (70) SCA * (<-10) Cr 63.3 89000 2A = 100 I (83) SC * (77) SCA * (<-50) Cr 79 20 200 2B = 100 I (90) SCA * (< -20) Cr 141 7635 2C = 100 I (143) SA (125) SCA * (27) SIA * (-12) Cr 233 1785 The numbers in parentheses in the above phase series indicate the phase transition temperature (unit: ° C), I indicates an isotropic phase, SA indicates a smectic A phase, SC * indicates a ferroelectric phase, SCA * indicates an antiferroelectric phase, SIA * indicates an antiferroelectric smectic I phase, and Cr indicates a crystal phase. Response time I: Switching time from antiferroelectric state to ferroelectric state (unit: μsec) Response time II: Switching time from ferroelectric state to antiferroelectric state (unit: μsec)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Seiji Adachi 22nd Wadai, Tsukuba City, Ibaraki Pref. Mitsubishi Gas Chemical Company, Ltd.

Claims (13)

[Claims] 1. An optically active compound represented by the following general formula (1). Embedded image (Wherein, m is an integer of 4 to 12, n is an integer of 3 to 8, X, Y
Represents a hydrogen atom or one is a hydrogen atom and the other is a fluorine atom, and C * represents an asymmetric carbon. ) 2. The optically active compound according to claim 1, wherein m is 6 to 12 in the general formula (1). 3. The optically active compound according to claim 1, wherein n is 3 to 7 in the general formula (1). 4. An anti-ferroelectric liquid crystal compound represented by the following general formula (1), and an optically active compound represented by the following general formula (2). Ferroelectric liquid crystal composition. Embedded image (In the general formula (1), m is an integer of 4 to 12, n is an integer of 3 to 8,
X and Y each represent a hydrogen atom or one of them represents a hydrogen atom and the other represents a fluorine atom, and C * represents an asymmetric carbon. In the general formula (2), R represents a linear alkyl group having 6 to 12 carbon atoms, Z represents a hydrogen atom or a fluorine atom, A represents CH ₃ or CF ₃ , r represents 0 or 1, and A represents CH ₃ . When r is 0, p is an integer of 4 to 10,
When A is CF ₃ , r is 1, s is an integer of 5 to 8, and p is 2
Or 4, and C * represents an asymmetric carbon. ) 5. In the general formula (2), R has 6 carbon atoms.
4. The antiferroelectric liquid crystal composition according to claim 3, wherein 6. The antiferroelectric liquid crystal composition according to claim 3, wherein in the general formula (2), Z is an F atom. 7. The antiferroelectric liquid crystal composition according to claim 3, wherein p is 2 in the general formula (2). 8. The antiferroelectric liquid crystal composition according to claim 3, wherein the optically active compound represented by the general formula (1) is mixed in an amount of 5 to 40 mol% of the composition. 9. The antiferroelectric liquid crystal composition according to claim 3, wherein the optically active compound represented by the general formula (1) is mixed in an amount of 10 to 30 mol% of the composition. 10. The antiferroelectric liquid crystal composition according to claim 3, wherein the upper limit temperature of the antiferroelectric phase is 40 ° C. or higher and the lower limit temperature is 0 ° C. or lower. 11. The antiferroelectric liquid crystal composition according to claim 9, which has a smectic A phase on a higher temperature side than the antiferroelectric phase. 12. A simple matrix liquid crystal display device in which the antiferroelectric liquid crystal composition according to claim 3 is sandwiched between substrates on which scanning electrodes and signal electrodes are arranged in a matrix. 13. The simple matrix liquid crystal display device according to claim 11, wherein driving by voltage is performed by switching between one antiferroelectric state, two ferroelectric states, and an intermediate between them.