JPH0228289A - Liquid crystal composition and liquid crystal element containing the same composition - Google Patents

Abstract

PURPOSE:To provide a ferroelectric chiral smectic liquid crystal composition containing two specific kinds of compounds, having good switching characteristics and large driving voltage margin and capable of keeping the image in good state even if the display area of the element has a temperature distribution. CONSTITUTION:The objective composition contains (A) at least one kind of the compound of formula I [1 is 1-18C (substituted) alkyl; R2 is 1-14C (substituted) alkyl; X1 and X2 are single bond, -O-, -OC(O)- or -C(O)O-; m is 0-7; n is 0 or 1] (e.g., the compound of formula II) and (B) at least one kind of the compound of formula III [R3 and R4 are 1-18C straight-chain alkyl wherein one of CH2 which is not bonded to X4 may be replaced by -O-; X3 and X4 are single bond, -O-, -OC(O)-, -C(O)O- or -OC(O)O-; p and q are 0-2] (e.g., the compound of formula IV).

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a liquid crystal composition used for liquid crystal elements used in liquid crystal display elements, liquid crystal light shutters, etc. This invention relates to a liquid crystal composition.

[Background technology]

Conventionally, liquid crystals have been applied as electro-optical elements in various fields. Most of the liquid crystal elements currently in practical use are, for example, M, 5chadt and W, “Applied Physics Letters” by Helfrich.
Vo, 18, No. 4 (1971, 2, 15), P
, 127-128 “Voltage-8 penden
t 0ptical Activity of
aTwisted Nematic Liqui
d TN (twiste) shown in Crystabi
It uses a d nematic type liquid crystal.

These are based on the dielectric alignment effect of liquid crystals, and due to the dielectric anisotropy of liquid crystal molecules, the average molecular axis direction is oriented in a specific direction by an applied electric field. It is said that the limit of the optical response speed of an element is milliseconds, which is too slow for multi-purpose applications.On the other hand, for applications in large flat displays, the simple matrix method is recommended in terms of cost, productivity, etc. In the simple matrix method, an electrode configuration in which a scanning electrode group and a signal electrode group are arranged in a matrix is adopted.
To drive this, a time-division drive method is adopted in which address signals are selectively and periodically applied to the scanning electrode group, and predetermined information signals are selectively applied in parallel to the signal electrode group in synchronization with the address signal. be done.

However, if the above-mentioned TN type liquid crystal is used as an element of such a driving method, there will be an area where the scanning electrode is selected and the signal electrode is not selected, or an area where the scanning electrode is not selected and the signal electrode is selected (the so-called "half area"). A finite electric field is also applied to the selection point "). If the difference between the voltage applied to the selected point and the voltage applied to the half-selected point is sufficiently large, and the voltage threshold required to align the liquid crystal molecules perpendicular to the electric field is set to an intermediate voltage value, the display element will It works normally, but if you increase the number of scanning lines (N), the entire screen (
The time during which an effective electric field is applied to one selected point (duty ratio) decreases at a rate of 1/N while scanning 1 frames). For this reason, (the voltage difference as an effective value applied to the selected point and non-selected point when repeated scanning is performed is
As the number of scanning lines increases, the size becomes smaller, resulting in unavoidable drawbacks such as a reduction in image contrast and crosstalk.

This phenomenon is caused by liquid crystals that do not have bistability (the stable state is when the liquid crystal molecules are aligned horizontally with respect to the electrode surface, and they are aligned vertically only while an electric field is effectively applied). ) is essentially an unavoidable problem that arises when driving using the temporal accumulation effect (that is, repeatedly scanning). In order to improve this point, voltage averaging method, dual-frequency driving method, multiple matrix method, etc. have already been proposed, but all of these methods are insufficient, and it is necessary to increase the screen size and density of display elements. Currently, the number of scanning lines has reached a plateau due to the inability to increase the number of scanning lines sufficiently.

In order to improve the drawbacks of conventional liquid crystal elements, the use of bistable liquid crystal elements has been proposed for C1ark and L
proposed by Agerwall (Japanese Unexamined Patent Application Publication No. 1983-1999)
107216, US Pat. No. 4,367,924, etc.). As the bistable liquid crystal, a ferroelectric liquid crystal having a chiral metal C phase (SmC*) or H phase (SmH*) is generally used. This ferroelectric liquid crystal has a bistable state consisting of a first optically stable state and a second optically stable state in response to an electric field, and therefore is different from the optical modulation element used in the above-mentioned TN type liquid crystal. Differently, for example, the liquid crystal is oriented in a first optically stable state with respect to one electric field vector, and the liquid crystal is oriented in a second optically stable state with respect to the other electric field vector. Further, this type of liquid crystal has a property (bistability) of taking one of the above two stable states in response to an applied electric field and maintaining that state when no electric field is applied.

In addition to the above-mentioned feature of bistability, ferroelectric liquid crystals have the excellent feature of high-speed response. This is because the spontaneous polarization of the ferroelectric liquid crystal and the applied electric field directly act to induce a transition in the orientation state, which is 3 to 4 orders of magnitude faster than the response speed due to the effect of the dielectric anisotropy and the electric field.

In this way, ferroelectric liquid crystals potentially have extremely excellent properties, and by utilizing these properties, many of the problems of conventional TN-type devices mentioned above can be overcome, which is quite essential. Improvement can be obtained.

In particular, it is expected to be applied to high-speed optical shutters and high-density, large-screen displays.

In the case of a simple matrix display device as described above using an element in which this ferroelectric liquid crystal layer is sandwiched between a pair of substrates, for example, Japanese Patent Laid-Open Nos. 59-193426 and 59-193 disclose
No. 427, No. 60-156046 and No. 60-
The driving method disclosed in Japanese Patent No. 156047 and the like can be applied.

FIG. 4 is a waveform diagram of the driving method used in the embodiment of the present invention. Further, FIG. 5 is a plan view of a ferroelectric liquid crystal panel 51 on which matrix electrodes used in the present invention are arranged. Fifth
In the panel 51 shown in the figure, a scanning line 52 and a data line 53 are wired to cross each other, and a ferroelectric liquid crystal is disposed between the scanning line 52 and the data line 53 at the intersection.

In FIG. 4(A), Ss is the selected scanning waveform applied to the selected scanning line, SN is the non-selected scanning waveform that is not selected, and ■8 is the selected information waveform applied to the selected data line ( IN represents a non-selection information signal (white) applied to an unselected data line. Also, in the figure (IS
-3S) and (IN ss) are the voltage waveforms applied to the pixels on the selected scanning line, the pixels to which the voltage (rs ss) is applied take a black display state, and the voltage (IN ss
) to which the pixel is applied assumes a white display state.

FIG. 4(B) is a time series waveform when the display shown in FIG. 6 is performed using the drive waveform shown in FIG. 4(A).

In the driving example shown in FIG. 4, the minimum application time Δt of the unipolar voltage applied to the pixels on the selected scanning line corresponds to the time of the write phase t2, and the time of the 1-line clear t1 phase is 2Δt. It is set to t.

Now, each parameter V5 of the drive waveform shown in FIG. V
, , Δt is determined by the switching characteristics of the liquid crystal material used.

FIG. 7 shows the change in transmittance T, that is, the V-T characteristic, when the driving voltage (V S +V I) is changed while keeping the bias ratio, which will be described later, constant.

Here, △t=50μs1 bias ratio V m/(v
+V, ) = 1/3. The positive side of Figure 7 is shown in Figure 4 (IN SS), and the negative side is (I5-SS).
) is applied. Here, vI +v3 are respectively referred to as an actual drive threshold voltage and a crosstalk voltage. However, v2〈vIkuv3) and △V=(V3 Vl
) is called the voltage margin and is the voltage width that allows matrix drive. It can be said that v3 generally exists in FLC matrix drive.

Specifically, it is the voltage value that causes switching by v8 in the waveform of FIG. 4(A) (IN SS).

Of course, it is possible to increase the value of v3 by increasing the bias ratio, but increasing the bias ratio means increasing the amplitude of the information signal, which may lead to an increase in flickering in terms of image quality. This is undesirable because it causes a decrease in contrast. In our study, a bias ratio of about 173 to 1/4 is practical. By the way, if the bias ratio is fixed, the voltage margin △V strongly depends on the switching characteristics of the liquid crystal material. It goes without saying that a liquid crystal material having a large value of .DELTA.V is very advantageous for driving a matrix.

At a certain temperature like this, it is possible to write two states, "black" and "white", into the selected pixel by changing the two directions of the information signal, and unselected pixels can write the "black" or "white" state into the selected pixel. The upper and lower limits of the applied voltage that can maintain this state and their widths (driving voltage margin ΔV) differ between liquid crystal materials and are unique. The drive margin also changes due to changes in the environmental temperature (therefore, in the case of an actual display device, it is necessary to set the drive voltage to be optimal for the liquid crystal material and the environmental temperature.

However, in practice, when expanding the display area of such a matrix display device, the difference in the environment in which the liquid crystal exists in each pixel (specifically, the temperature and the cell gap difference between electrodes) naturally increases. However, with a liquid crystal display having a small driving voltage margin, it is not possible to obtain a good image over the entire display area.

[Problem that the invention seeks to solve]

In order to put ferroelectric liquid crystal elements into practical use, the present invention has a large drive voltage margin and a wide drive temperature margin that allows all pixels to be satisfactorily driven in matrix even if there is a certain degree of temperature variation over the display area of the liquid crystal element. An object of the present invention is to provide a chiral smectic liquid crystal composition and a liquid crystal element using the liquid crystal composition.

Means for Solving Problem U] The present invention is based on the following general formula (I) (wherein R1 is a linear or branched alkyl group which may have a C1 to C+S substituent, and R2 is a C8 ~C
A linear or branched alkyl group that may have 14 substituents, Xl and x2 are single bonds, -0-QC-, -Co
-1m is O to 7, n is O or 1), and at least one compound represented by the following general formula (II) (wherein R3*R4 is a C8 to C18 linear alkyl group, and the alkyl 1 that does not bond with x4 in the group
CH2 may be replaced with -O-.

p and q are 0, l or 2. The present invention provides a ferroelectric chiral smectic liquid crystal composition characterized by containing at least one of the compounds shown in the formula (1) and a liquid crystal element in which the liquid crystal composition is disposed between a pair of electrode substrates.

Among the compounds represented by the above-mentioned general formula (1), preferred examples of compounds include X, X2, and the following (I-4) to (1).
-iv).

(1-i) X, is a single bond, X2 is -〇(
I-ii) XI is a single bond, x2 is -OC
(1-iii) Xl is a single bond, x2 is −
CO-(I iv)

Furthermore, among the compounds represented by the aforementioned general formula (II),
Preferred examples of compounds include the following (II-a) to (
Examples include compounds represented by II-e).

(R3, R4+ X3.
Preferred examples of 3°x4 are (II-i) to (II
-viii).

(II-i) (II-ii) (II-iii) (II-iv) X3 is a single bond, x4 is a single bond, x3 is a single bond, X4 is -〇-X3 is a single bond, x
4 is -OC-X3. , X4 is a -CO single bond, and x3 is -0-1 (II-vi) X3 is 10-1 (II-vii) X3 is 10-1 (II-V) 〇-X4 is 10C- (II-viii) A preferable example of R4 is (II-iX
) to (II −x ).

(II-ix) R3 is an n-alkyl group, R4
is n-alkyl group (II-x), R3 is n-alkyl group, R4 is -ecH2″+, 0-R5 (S is 1-12
, Rls is a linear alkyl group having 1 to 16 carbon atoms) Examples of specific structural formulas of the liquid crystal compound represented by the above general formula are shown below.

l-36 A typical synthesis example of the compound represented by the general formula (1) is shown below.

Synthesis Example 1 (Synthesis of compound No. 1-20) 1.06 5-methoxyhexanol dissolved in 5mf of pyridine
g (8.0 mmol) of p-toluenesulfonic acid chloride dissolved in 5 ml of pyridine (
9.6 mmol) was added dropwise at below 5°C in an ice water bath.

After stirring for 6 hours at room temperature, the reaction mixture was poured into 100 mj' of cold water. After making the mixture acidic with 6N hydrochloric acid, the mixture was extracted with isopropyl ether. The organic layer was washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off to obtain 5-methoxyhexyl-p-toluenesulfonate.

Dimethylformamide 10m! ! 5-decyl-2-(
p-hydroxyphenyl)pyrimidine 2.0g (6,4
1 mmo+), 0.61 g of potassium hydroxide was added, and 10
Stirred at 0°C for 40 minutes. To this was added the previously obtained 5-methoxyhexyl-p-toluenesulfonate, and 100
The mixture was heated and stirred at ℃ for 4 hours. After the reaction is complete, pour 100ml of cold water into the reaction mixture! and extracted with benzene. After washing with water, it was dried over anhydrous magnesium sulfate and the solvent was distilled off to obtain a pale yellow oil. After purification by column chromatography (silica gel - ethyl acetate/benzene = 179), it was recrystallized from hexane to give 5-decyl-2-(4-(
5'-Methoxyhexyloxy)phenyl)pyrimidine (Compound No.

1-20) 1.35g was obtained.

Phase transition temperature ('C) Synthesis Example 2 (Synthesis of compound No. 1-25) 2.04 g of 6-pentyloxyheptanol was added to 8 ml of pyridine.
After dissolving in cold water, 2.26 g of tosyl chloride dissolved in 5 mjl' of pyridine was gradually added dropwise (below 5°C, 7 minutes). Thereafter, the mixture was stirred at room temperature for 5 hours.

Pour the reaction mixture into 150 m of ice water! After adjusting the pH to about 3 with a 6N aqueous hydrochloric acid solution, the mixture was extracted with ethyl acetate.

After washing with water and drying over anhydrous magnesium sulfate, the solvent was distilled off to obtain 2.98 g of (6-pentyloxyheptyl)p-toluenesulfonate.

3.12 g of 5-n-decyl-2-(4-hydroxyphenyl)pyridine and 0.53 g of potassium hydroxide were added to 14 mj of dimethylformamide! After heating and stirring at 100°C for 3 hours, 2.98g of (6-pentyloxyheptyl)p-1 luenesulfonate was added and the solution was heated at 100°C for 5 hours.
The mixture was heated and stirred for hours.

The reaction mixture was poured into 200 ml of ice water, adjusted to pH approximately 3 with 6N aqueous hydrochloric acid solution, and then extracted with benzene. This was washed with water, dried over anhydrous magnesium sulfate, and the solvent was distilled off to obtain 4.71 g of a crude product. This was purified by silica gel column chromatography (n-hexane/ethyl acetate-10/2)
, and further recrystallized from hexane to obtain 1.56 g of 5-n-decyl-2-[4-(6-pentyloxyhebutyloxy)phenyl]pyrimidine.

IR (cm-') 2924.2852, 1610, 1586, 1472° 1436.1254, 1168, 1096. 798 Phase transition temperature (℃) 22.7 33.3 3
9.8 For compounds other than the synthesis side, use the following synthetic route A
.

It can be obtained by B.

Synthetic route A Synthetic route B (In the above R , R2,X , m, and n are as described above. ) The general formula (n) A liquid crystal compound represented by An example of a physical structural formula is shown below.

The compound represented by the general formula (II) is, for example, East German Patent No. 9
5892 (1973), Patent Publication Sho 62-5434
(1987).

Further, for example, the compound represented by can be synthesized by the following synthetic route.

(R3゜ in the formula R4+ p.

(q is as described above) The liquid crystal composition of the present invention comprises at least one compound represented by the general formula (I), at least one compound represented by the general formula (II), and further at least one compound represented by the general formula (II). Liquid crystal compound 1
It can be obtained by mixing at least one species in an appropriate ratio. Further, the liquid crystal composition according to the present invention is preferably a ferroelectric liquid crystal composition, particularly a ferroelectric chiral smectic liquid crystal composition.

Specific examples of other liquid crystal compounds used in the present invention are listed below.

F υ υ υ Soot The liquid crystalline compound represented by the general formula (I) and the liquid crystalline compound represented by the general formula (II) of the present invention, and one or more of the other liquid crystalline compounds mentioned above, or a strong liquid crystalline compound containing the same. Dielectric liquid crystal composition (hereinafter abbreviated as ferroelectric liquid crystal material)
The orientation ratio is per 100 parts by weight of the ferroelectric liquid crystal material,
It is preferable that each of the liquid crystal compounds represented by the general formula (1) and the general formula (II) of the present invention be contained in an amount of 1 to 300 parts by weight, more preferably 5 to 100 parts by weight.

In addition, when using two or more of one or both of the liquid crystal compounds represented by the general formula (1) and general formula (II) of the present invention, the blending ratio with the ferroelectric liquid crystal material is as described above. Per 100 parts by weight, 1 to 500 parts by weight, more preferably 10 to 100 parts by weight of a mixture of two or more of one or both of the liquid crystalline compounds represented by the general formula (I) and general formula (11) of the present invention. It is preferable to do so.

FIG. 1 is a schematic cross-sectional view of an example of a liquid crystal element having a ferroelectric liquid crystal layer according to the present invention, for explaining the structure of the ferroelectric liquid crystal element.

In FIG. 1, the symbol l is a ferroelectric liquid crystal layer, 2 is a glass substrate, 3 is a transparent electrode, 4 is an insulating alignment control layer, 5 is a spacer, 6 is a lead wire, 7 is a power source, 8 is a polarizing plate, 9 indicates a light source.

The two glass substrates 2 each have In2O3゜5n0
2 or ITO (Indium-Tin Oxid
A transparent electrode made of a thin film such as e) is coated. On top of this, a thin film of a polymer such as polyimide is rubbed with gauze or acetate flocked cloth to form an insulating alignment control layer that aligns the liquid crystals in the rubbing direction. Insulating materials such as silicon nitride, hydrogen-containing silicon carbide, silicon oxide, boron nitride, hydrogen-containing boron nitride, cerium oxide, aluminum oxide, zirconium oxide, titanium oxide, and fluoride Form an insulating layer of inorganic material such as magnesium, and then apply polyvinyl alcohol, polyimide, polyamideimide, polyesterimide, polyparaxylene, polyester, polycarbonate, polyvinyl acecool, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose. An organic insulating material such as resin, melamine resin, Yulia resin, acrylic resin or photoresist resin is used as an orientation control layer.
The insulating orientation control layer may be formed of two layers (or may be a single layer of an insulating orientation control layer of an inorganic material or an insulating orientation control layer of an organic material. If it is organic, it can be formed by a vapor deposition method, etc. If it is organic, it is a solution in which an organic insulating material is dissolved or its precursor solution (solvent 0.1 to 20% by weight, preferably 0.2 to 10% by weight)
It can be applied by a spinner coating method, dip coating method, screen printing method, spray coating method, roll coating method, etc., and cured and formed under predetermined curing conditions (for example, under heating).

The thickness of the insulating orientation control layer is usually 30 to 1 μm, preferably 30 to 3000, more preferably 50 to 1 μm.
000 people is suitable.

These two glass substrates 2 are kept at an arbitrary distance by a spacer 5. For example, using silica beads or alumina beads with a predetermined diameter as spacers, the glass substrate 2
There is a method in which the material is held between two sheets and the surrounding area is sealed using a sealing material such as an epoxy adhesive. In addition, a polymer film or glass fiber may be used as a spacer.

A ferroelectric liquid crystal is sealed between these two glass substrates.

The ferroelectric liquid crystal layer in which the ferroelectric liquid crystal is sealed is generally 0.5 to 20 μm, preferably 1 to 5 μm.

In addition, this ferroelectric liquid crystal has an SmC* phase (chiral smectic C phase) in a wide temperature range including room temperature (especially on the low temperature side), and when used as an element, the driving voltage margin and driving temperature margin are It is desired that it be wide.

In addition, in order to exhibit good uniform alignment and obtain a monodomain state especially when used as an element, the ferroelectric liquid crystal must be changed from the tomoytic phase to the ch phase (cholesteric phase) - 3mA phase (smectic A phase) - SmC* phase. (Chiral smectic C phase)
It is desirable to have the following phase transition series.

The transparent electrode 3 is connected to an external power source 7 by a lead wire.

Further, a polarizing plate 8 is bonded to the outside of the glass substrate 2.

The device shown in FIG. 1 is of a transparent type and is equipped with a light source 9.

FIG. 2 schematically depicts an example of a cell for explaining the operation of a ferroelectric liquid crystal element. 21a and 21b are In2O3, 5n02 or ITO (Indiu
It is a substrate (glass plate) coated with a transparent electrode made of a thin film such as (m-Tin Oxide), between which a liquid crystal of SmC wood phase or SmH* phase is oriented so that the liquid crystal molecular layer 22 is perpendicular to the glass surface. It is enclosed. A thick line 23 represents a liquid crystal molecule, and this liquid crystal molecule 2
3 has a dipole moment (P soil) 24 in the direction perpendicular to its molecule. When a voltage higher than a certain threshold is applied between the electrodes on the substrates 21a and 21b, the helical structure of the liquid crystal molecules 23 is unraveled, and the liquid crystal molecules 23 are aligned in the direction such that all the dipole moments (P) 24 are directed in the direction of the electric field. can be changed. The liquid crystal molecules 23 have an elongated shape and exhibit refractive index anisotropy in the long axis direction and short axis direction,
Therefore, it is easily understood that, for example, if crossed Nicol polarizers are placed above and below a glass surface, a liquid crystal optical modulation element whose optical characteristics change depending on the polarity of applied voltage can be obtained.

The liquid crystal cell preferably used in the optical modulation element of the present invention can have a sufficiently thin thickness (for example, IOμ or less). As the liquid crystal layer becomes thinner, the helical structure of the liquid crystal molecules unravels even when no electric field is applied, as shown in Figure 3, and the dipole moment Pa or pb is directed upward (34a) or downward (34b). ). In such a cell, as shown in FIG.
is applied by the voltage applying means 31a and 31b, the dipole moment changes direction to upward direction 34a or downward direction 34b corresponding to the electric field vector of electric field Ea or Eb,
Accordingly, the liquid crystal molecules are aligned in either the first stable state 33a or the second stable state 33b.

As mentioned above, there are two advantages to using such ferroelectricity as an optical modulation element.

The first is that the response speed is extremely fast, and the second is that the alignment of liquid crystal molecules has bistability. To further explain the second point with reference to FIG. 3, for example, when the electric field Ea is applied, the liquid crystal molecules are oriented in a first stable state 33a, and this state remains stable even when the electric field is turned off. Furthermore, when an electric field Eb in the opposite direction is applied, the liquid crystal molecules are oriented to the second stable state 33b and change their orientation, but they remain in this state even after the electric field is turned off. Also, the electric field E
As long as a or Eb does not exceed a certain threshold, the respective previous orientations are maintained.

When a simple matrix display device is constructed using a device in which a ferroelectric liquid crystal material having such characteristics is sandwiched between a pair of substrates,
For example, Japanese Unexamined Patent Publication No. 59-193426, No. 59-19
No. 3427, No. 60-156046 and No. 60
The driving method disclosed in Japanese Patent No.-156047 and the like can be applied.

FIG. 4 is a waveform diagram of the driving method used in the embodiment of the present invention. Further, FIG. 5 is a plan view of a ferroelectric liquid crystal panel 51 on which matrix electrodes used in the present invention are arranged. In the panel 51 of FIG. 5, a scanning line 52 and a data line 53 are wired to cross each other, and a ferroelectric liquid crystal is arranged between the scanning line 52 and the data line 53 at the intersection. .

In FIG. 4(A), Ss is the selection scanning waveform applied to the selected scanning line, S8 is the unselected scanning waveform that is not selected, and Is is the selection information waveform (black) applied to the selected data line. ), IN represents a non-selection information signal (white) applied to an unselected data line. Also, in the figure (I
s Ss) and (■, SS) are the voltage waveforms applied to the pixels on the selected scanning line, the pixels to which the voltage (Is Ss) is applied display black, and the voltage (■E15S)
The pixel to which is applied assumes a white display state.

FIG. 4(B) is a time series waveform when the display shown in FIG. 6 is performed using the drive waveform shown in FIG. 4(A).

In the driving example shown in FIG. 4, the minimum application time Δt of the unipolar voltage applied to the pixels on the selected scanning line corresponds to the time of the write phase t2, and the time of the l line clear t1 phase corresponds to 2Δt. It is set to t.

Now, each parameter Vs, V of the drive waveform shown in FIG.
,, Δt is determined by the switching characteristics of the liquid crystal material used. FIG. 7 shows the change in transmittance T, that is, the V-T characteristic, when the driving voltage (vs+V, ) is changed while keeping the bias ratio constant, which will be described later. Here, △t=50 μs, bias ratio V/
(Vl + VS) = 1/31: Fixed. The positive side of Figure 7 is shown in Figure 4 (IN ss)
, a waveform indicated by (ts ss) is applied to the negative side.

Here, V, V3 are called actual drive threshold voltage and crosstalk voltage, respectively. However, v2<v, <v3) and △
V=(V3 Vl) is called a voltage margin and is a voltage width that allows matrix driving. It can be said that v3 generally exists in FLC matrix drive. in particular,
vB' in the waveform of Fig. 4 (A) (IN ss)
This is the voltage value that causes switching. Of course, it is possible to increase the value of v3 by increasing the bias ratio, but increasing the bias ratio means increasing the amplitude of the information signal, which may lead to an increase in flickering and a decrease in contrast in terms of image quality. This is undesirable as it causes a decline in the quality of the product. According to our study, a bias ratio of about 1/3 to 174 is practical. By the way, if the bias ratio is fixed, the voltage margin △V strongly depends on the switching characteristics of the liquid crystal material, and △
It goes without saying that a liquid crystal material with a large V is very advantageous for matrix driving.

At a certain temperature like this, it is possible to write two states, "black" and "white", into a selected pixel depending on the two directions of the information signal, and non-selected pixels can write the "black" state into the selected pixel.
Or the upper and lower limits of the applied voltage that can maintain the "white" state and their widths (drive voltage margin △V)
is different and unique among liquid crystal materials. In addition, the drive margin decreases due to changes in the environmental temperature, so
In the case of an actual display device, it is necessary to set the drive voltage to the optimum value for the liquid crystal material and environmental temperature.

However, when the display area of such a matrix display device is expanded in practice, the difference in the environment in which the liquid crystal exists in each pixel (specifically, the difference in temperature and cell gap between electrodes) naturally increases. With a liquid crystal having a small driving voltage margin, it is not possible to obtain a good image over the entire display area. isn't it.

Example 1 A liquid crystal composition 1-A was prepared by mixing the following parts by weight.

C, II, 0CII□CIl□o@-coo@@-c
ooc, H,3 To this liquid crystal composition 1-A, exemplified compounds 1-3゜2-8 were mixed in the following parts by weight,
A liquid crystal composition 1-B was obtained.

Exemplary compound no.

Structural Formula Next, optical responses were observed using cells prepared using these liquid crystal compositions according to the following procedure.

Two glass plates with a thickness of 1 and 1 mm were prepared, an ITO film was formed on each glass plate to create a voltage application electrode, and Si02 was further vapor-deposited thereon to form an insulating layer.

On this substrate, a polyimide resin precursor [Toshi ■ 5P-51
0] 1.0% dimethylacetamide solution at 30 revolutions
Coating was performed for 15 seconds using a 0Or, p, m spinner. After the film was formed, a heating condensation firing process was performed at 300° C. for 60 minutes. The thickness of the coating film at this time was about 120 people.

After this firing, the film was rubbed with acetate flocked cloth, then washed with isopropyl alcohol solution, and silica beads with an average particle size of 1.5 μm were sprinkled on one glass plate. With the axes parallel to each other, glue the glass plates together using an adhesive sealant [Rixon Bond (Chisso)], and
A cell was prepared by heating and drying at 100'C for 1 minute. The cell thickness of this cell was measured using a Bereck phase plate and was found to be approximately 1.5 μm.

A ferroelectric liquid crystal element was prepared by injecting the liquid crystal composition 1-B described above in an isotropic liquid state into this cell and slowly cooling it from the isokyoshi phase to 25°C at a rate of 20°C/h.

Using this ferroelectric liquid crystal element, drive voltage margin △V(
V3 V2) was measured. The results are shown below (in addition,
△t is set so that v2 is approximately 15V).

10℃ 25℃ 40℃ Drive voltage margin 12. OV 12.5V 10.
OV (Measurement setting △t) (735μ5ec)
(220μ5ec) (74, [Z 5ee) Furthermore, if the voltage is set to the median value of the drive voltage margin at 25°C and the measurement temperature is changed, the driveable temperature difference (hereinafter referred to as drive temperature margin) is ±3. The temperature was 3°C.

Furthermore, the contrast during this drive at 25°C is 10
Met.

Comparative Example 1 Liquid crystal composition 1 in which only exemplary compound No. 2-8 was mixed with 1-A without mixing exemplary compound No. 1-3 of liquid crystal composition 1-H mixed in Example 1. Liquid crystal composition 1-D in which only exemplary compound No. 1-3 was mixed with l-A without mixing -C and exemplary compound No. 2-8
It was created.

Instead of using liquid crystal composition 1-B, liquid crystal composition 1-A,
A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that l-C and 1-D were injected into the cell, and the driving voltage margin ΔV was measured.The results are shown below. .

Drive voltage margin (setting △t during measurement) 10℃ 25℃ 40℃ 1-A 9. OV 9.5V 8
,5V (1050tt 5ec) (280a 5e
c) (78a 5ec) 1-CQ, gV
lo, OV 9.0V (915μ5ec)
(265g, 5ec) (76p 5ec)
1-D 9.1; V to, ov
9.0V (920μ5ec) (260μ5ec
) (75p 5ec) Furthermore, the driving temperature margin at 25°C is ±2.2°C at 1-A and ±2.2°C at 1-C.
It was ±2.5°C at 4°C and 1-D.

It has an excellent ability to maintain good images despite temperature changes and cell gap variations.

Example 2 In contrast to the liquid crystal composition 1-A mixed in Example 1, a liquid crystal composition 2-B was obtained.

A ferroelectric liquid crystal device was prepared in the same manner as in Example 1, except that this structural formula was used, and the drive margin was measured in the same manner as in Example 1, and the switching state, etc., was observed. The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

10℃ 25℃ 40℃ Drive voltage margin 12.5V 13. OV 10.
OV (Measurement setting △t) (700μ5ec)
(213μ5ec) (76p 5ec) 25 more
The driving temperature margin at °C is ±3. r:°C. Further, the contrast during this driving at this temperature was 9.

Comparative Example 2 Among the liquid crystal compositions 2-B mixed in Example 2, Exemplified Compound No. 1-10.1-20 was not mixed, and Exemplified Compound No. 2-58.2-84 was used for 1-A. Liquid crystal composition 2-C mixed with Exemplary Compound No. 2-58.2-84
Exemplary compound No. 1-10 for 1-A without mixing
A liquid crystal composition 2-D was prepared by mixing only ゜1-20.

Instead of using liquid crystal composition 1-B, liquid crystal composition 1-A,
A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that 2-C and 2-D were injected into the cell, and the driving voltage margin ΔV was measured. The results are shown below.

Drive voltage margin (M△t during measurement) 10°C 25°C 40°C 1-A 9. OV 9.5V 8
．． 5V (1050μ5ec) (280μ5ec)
(78μ5ec) 2-Cro, ov 10
．． ';V 9.0V (895μ5ec)
(250p 5ec) (76p 5ec) 2 D
to, oV 1o, ov I!
KV (820μ5ec) (240μ5ec)
(76μ5ec) Furthermore, the driving temperature margin at 25℃ is ±2.2℃ for 1-A, ±2.6℃ for 2-C, 2
-D was ±2.4°C.

The drive margin of the second type is wider, and it has an excellent ability to maintain good images against changes in environmental temperature and variations in cell gap.

Example 3 Liquid crystal composition 1-A mixed in Example 1 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 3-B.

A ferroelectric liquid crystal element was fabricated in the same manner as in Example 1 except that this was used, and the drive margin was measured in the same manner as in Example 1, and the switching state and the like were observed. The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

10℃ 25℃ 40℃ Drive voltage? −
Shin 13. OV 7 mouths, II) V 1
0.5V (setting △t during measurement) (lJOμ5ec)
(195 μ5 ec) (73 μ5 ec) Furthermore, the driving temperature margin at 25° C. was ±3.6° C. Further, the contrast during this driving at this temperature was 11.

Comparative Example 3 Among the liquid crystal compositions 2-B mixed in Example 3, 1-A was prepared without mixing exemplified compounds No. 1-6 and 1-26.
Liquid crystal composition 3-C, which is a mixture of only exemplary compounds No. 2-9 and 2-44, and exemplary compound No. 2-9.
Exemplary compound No. for 1-A without mixing 2-44,
A liquid crystal composition 3-D was prepared by mixing only 1-6° and 1-26.

Liquid crystal composition 1-B is used instead of liquid crystal composition 1-B.
All (
A ferroelectric liquid crystal element was produced in the same manner as in Example 1, and the driving voltage margin ΔV was measured. The results are shown below.

Drive voltage margin (setting △t during measurement) 10℃ 25℃ 40℃ 1-A 9. OV 9.5V 8
．． 5V (1050μ5ec) (280μ5ec)
(78μ5ec)3-C/0. OV 1
0.5V 9.0V (895μ5ec)
(250μ5ec) (76μ5ec) 3D
10. OV 10. OV ri, 0V
(760μ5ec) (235μ5ec) (
Furthermore, the driving temperature margin at 25°C is ±2.2°C for l-A, ±2.5°C for 3-C, and ±2.5°C for 3-D.
±2. '; It was −℃.

The child has a wider drive margin and is better able to maintain good images against changes in environmental temperature and variations in cell gap.

Example 4 Liquid crystal composition 1-A mixed in Example 1 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 4-B.

-A A ferroelectric liquid crystal element was produced in the same manner as in Example 1 except for using this, and the drive margin was measured in the same manner as in Example 1, and the switching state etc. were observed.

The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

10℃ 25℃ 40℃ Drive voltage merge: / 13. OV13
．． 5V 10.5V (setting △t during measurement)
(680μ5ec) (200μ5ec) (72
μ5ec) Furthermore, the driving temperature margin at 25°C was ±3.8°C. Further, the contrast during this driving at this temperature was 10.

Comparative Example 4 Among the liquid crystal compositions 4-H mixed in Example 4, Exemplary Compound No. 1-13. 1-17. Exemplary compound No., 2-62, 2-9 for 1-A without mixing 1-35
Liquid crystal composition 4-C in which only No. 3 was mixed and exemplary compound No.
Exemplary compound No. 1-13 for 1-A without mixing 2-62°2-93. 1-17. A liquid crystal composition 4-D was prepared by mixing only 1-35.

Instead of using liquid crystal composition 1-B, liquid crystal composition 1-A,
A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that 4-C and 4-D were injected into the cell, and the driving voltage margin ΔV was measured. The results are shown below.

Drive voltage margin (mt during measurement) 10°C 25°C 40°C 1-A 9. OV 9.5V 8
．． 5V (1050p 5ec) (280μ5ec)
(78μ5ec)4-CY<;V/θ, oV
g, sag (895μ5ec) (250
μ5ec) (76μ5ec)4-D 11.
5V 12. OV 9.0V (750
μ5ec) (220μ5ec) (74p
The driving temperature margin at 5ec)° and 25°C is:
The temperature was ±2.2°C for 1-A, ±2.7°C for 4-C, and 2° above 4-°C for 4-D.

The child has a wider drive margin 1i, and has an excellent ability to maintain a good image against changes in environmental temperature and variations in cell gap.

Example 5 Liquid crystal composition 5 mixed in the following parts by weight Create A did.

C4H Set 2CH, 0@-C Asa O-C Shizu H13C+oH
210@-Coo@Hato HI3 C1゜)+2.0@-COO@Hato''+7 Exemplary compounds 1-3゜2-8 were mixed with the liquid crystal composition 5-A in the following parts by weight, and the liquid crystal composition 5-A was mixed with the following parts by weight. Composition 5-B was obtained.

Exemplary Compound NO0 A ferroelectric liquid crystal element was prepared in the same manner as in Example 1 except that this liquid crystal composition 5-H was used in place of the structural formula liquid crystal composition 1-B.
The driving voltage margin ΔV was measured in the same manner as in Example 1, and the switching state and the like were observed.

The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

10'C25°C40°C Drive voltage merge: / 13.5V 13
．． 5V 9.5V (Measurement setting △t) (
840μ5ec) (260μsec”) (90
μ5ec) Furthermore, the driving temperature margin at 25°C was 3° to 4°C. Further, the contrast during this drive at this temperature was lO.

Comparative Example 5 Liquid crystal composition 5 in which only exemplary compounds No. 2-8 were mixed with 5 to A without mixing exemplary compound No. 1-3 of liquid crystal composition 5-B mixed in Example 5. A liquid crystal composition 5-2 was prepared by mixing only exemplary compound No. 1-3 with 5-A without mixing -C and exemplary compound No. 2-8.

Instead of using liquid crystal composition 5B, liquid crystal compositions 5-A and 5
A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that -C and 5-D were injected into the cell, and the driving voltage margin ΔV was measured. The results are shown below.

Drive voltage margin (measurement setting △t) 10℃ 25℃ 40℃5-A
10.5V 10.5V 8.5
V (1200u 5ec) (330u 5ec)
(98u 5ec)5-CIl, OV
Il, OV 9.0V (1020μ5ec
) (300p 5ec) (95p 5e
c) 5-D Il, OV Il,,';
V 9-Ov (1030μ5ec) (2
95μ5ec) (96p 5ec) Furthermore, 2
Driving temperature margin at 5℃ is ±2.5℃ at 5-A
, 1±2.7°C for 5-C, and ±2.8°C for 5-D.

The drive margin of the second type is wider, and it has an excellent ability to maintain good images against changes in environmental temperature and variations in cell gap.

Example 6 Liquid crystal composition 5-A mixed in Example 5 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 6-B.

A ferroelectric liquid crystal device was prepared in the same manner as in Example 1, except that this was used, and the drive margin was measured in the same manner as in Example 1, and the switching state etc. were observed. The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

10℃ 25℃ 40℃ Drive voltage merge 7 13.5V 13.5
V10. OV (setting at measurement △t) (7
80μ5ec) (248μ5ec) (92μ5ec)
ec) Furthermore, the driving temperature margin at 25°C is ±
The temperature was 3.4°C. Further, the contrast during this driving at this temperature was 10.

Comparative Example 6 Among the liquid crystal compositions 6-B mixed in Example 6, Exemplified Compound No. 1-10.1-20 was not mixed, and Exemplified Compound No. 2-58.2-84 was used for 5-A. Liquid crystal composition 6-C mixed with Exemplary Compound No. 2-58.2-84
Example compound No. 1-10 for 5-A without mixing
A liquid crystal composition 6-D was prepared by mixing only ゜1-20.

Instead of using liquid crystal composition 1-B, liquid crystal composition 5-A,
A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that 6-C and 6-D were injected into the cell, and the driving voltage margin ΔV was measured. The results are shown below.

Drive voltage margin (setting △t during measurement) 10℃ 25℃ 40℃ 5-A Io, 5V lo, 5V
8.5V (1200μ5ec) (330μ5
ec) (98μ5ec)6-C1/-taV
/1. ';V 9.0V (1050μ5e
c) (310μ5ec) (95μ5ec
)6-D It, OV //, OV
B, sagging (880μ5ec) (270μ
5ec) (93p 5ec) Furthermore, the driving temperature margin at 25℃ is ±2.5℃ for 5-A, 6-C
It was ±2.8°C at 6-D, and 2°8°C above at 6-D.

The drive margin of the second type is wider, and it has an excellent ability to maintain good images against changes in environmental temperature and variations in cell gap.

Example 7 A liquid crystal composition 7-A was prepared by mixing the following parts by weight.

C1゜■2, o@-coo@-oc, H.

Exemplary compound no.

Structural formula % Formula % Exemplary compound l-3゜2- for this liquid crystal composition 7-A
8 in the following weight parts, respectively, to prepare liquid crystal composition 7-B.
I got it.

Exemplary compound No., Structural formula
Weight part Ih -A A ferroelectric liquid crystal element was prepared in the same manner as in Example 1 except that liquid crystal composition 1-B was replaced with liquid crystal composition 7-B.
The driving voltage margin ΔV was measured in the same manner as in Example 1, and the switching state and the like were observed.

The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

10℃ 25℃ 40℃ Drive voltage margin 11. OV 11. O.V.
7.5V (setting at measurement △t) (280μ5
ec) (89, cz 5ec) (38B 5
ec) Furthermore, the driving temperature margin at 25°C is ±
The temperature was 3.0°C. Further, the contrast during this drive at this temperature was lO.

Comparative Example 7 Liquid crystal composition 7 in which only exemplary compound No. 2-8 was mixed with 7-A without mixing exemplary compound No. 1-3 of liquid crystal composition 7-B mixed in Example 7. Liquid crystal composition 7 in which only exemplary compound No. 1-3 was mixed with 7-A without mixing -C and exemplary compound No. 2-8.
-D was created.

Instead of using liquid crystal composition 7-B, liquid crystal composition 7-A,
A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that 7-C and 7-D were injected into the cell, and the driving voltage margin ΔV was measured. The results are shown below.

Drive voltage margin (setting △t during measurement) 10℃ 25℃40℃ 7-A 8. OV 8. O.V.
6.0V (400p 5ec) (110μ5
ec) (40μ5ec)7-C? ,01/
! OV 6.5V (3
45p 5ec) (100μ5ec)
(38μ5ec)7-D 9. OV 9
0V 6.5V (340μ5ec)
(98μ5ec) (38μ5ec) Furthermore, 2
Driving temperature margin at 5°C is ±1.9°C at 7-A
, 7-C was ±2.2°C, and 7-D was ±2.3°C.

The drive margin of the second type is wider, and it has an excellent ability to maintain good images against changes in environmental temperature and variations in cell gap.

Example 8 Liquid crystal composition 7-A mixed in Example 7 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 8-B.

A ferroelectric liquid crystal element was fabricated in the same manner as in Example 1 except that this was used, and the drive margin was measured in the same manner as in Example 1, and the switching state and the like were observed. The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

10℃ 25℃ 40℃ Pressure margin r1 for drive 1. OV lz, 3V
g, sv (setting at measurement △t) (260μ
5ec) (83μ5ec) (36μ5ec)
Furthermore, the driving temperature margin at 25°C is ±3.3
It was ℃. Further, the contrast during this driving at this temperature was 11.

Comparative Example 8 Among the liquid crystal compositions 8-B mixed in Example 8, Exemplary Compound No. 1-10. Example Compound No. 1-20 was not mixed with 7-A, and Exemplary Compound No. 2-58. Liquid crystal composition 8-C mixed with only 2-84 and exemplified compound No. 2-58.2-
Exemplary compound No. 1- for 7-A without mixing 84
A liquid crystal composition 8-D was prepared by mixing only 10°1-20.

Instead of using liquid crystal composition 8-B, liquid crystal composition 7-A,
A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that 8-C and 8-D were injected into the cell, and the driving voltage margin ΔV was measured.The results are shown below.

Drive voltage margin (measurement setting △t) 10℃ 25℃ 40℃7-A
8. Ov 8. ov 6.0v (
400μ5ec) (110μ5ec)
(40μ5ec) s-c q, ov
q, Ov 7.0v (350u 5ec
) (103μ5ec) (38μ5ec
)8-o g, r; v 9. Ov
b, tv (:340μ5ec) (
98μ5ec) (38p 5ec) Furthermore, 2
Driving temperature margin at 5°C is ±1.9°C at 7-A
, 8-C was ±2.3°C, and 8-D was ±2.2°C.

It has an excellent ability to maintain good images against changes in cell gap and variations in cell gap.

Example 9 Liquid crystal composition 1-B used in Example 1 and Comparative Example 1.

All of 1-C, 1-D, and 1-A were prepared in the same manner as in Example 1, except that the alignment control layer was made only of polyimide resin without using SiO2. The driving voltage margin was measured in the same manner as in Example 1. The results are shown below.

Drive voltage margin (setting △t during measurement) 10℃ 25℃ 40℃ 1-B 12.5V 13. O.V.
10.5V (710μ5ec) (205p
5ec) (7nt 5ee)1-CtO,OV
to, OV 9.0V (900μ5e
c) (Z'; Oμ5ec) (75μ5ec
)1-D 1o, OV /Iri, 5
V 9.0V (905μ5ec) (25
0μ5ec) (';f,p5ec)1-A
9.5V 10. OV9.0V
UfOμ5ec) (290μ5ec) C7
5μ5ec) Furthermore, the driving temperature margin at 25°C is 1-B ±3.5°C l-C ±2.5°C 1-D Upper 2°5°C 1-A ±2. ≠°C.

As is clear from Example 9, even when the device configuration is changed, the device containing the ferroelectric liquid crystal composition 1-B according to the present invention has the same performance as in Example 1 compared to the device containing other liquid crystal compositions. The drive margin is wide, and the ability to maintain good images despite changes in environmental temperature and variations in cell gap is excellent.

Example 10 Liquid crystal composition 2-B used in Example 2 and Comparative Example 2.

All of 2-C, 2-D, and 1-A were prepared in the same manner as in Example 1, except that the alignment control layer was made only of polyimide resin without using SiO□. The driving voltage margin was measured in the same manner as in Example 1. The results are shown below.

-B -C Drive voltage margin 10℃ 13.0V (670ttsee) fO, riV (860u 5ec) (Setting at measurement △t) 25℃ 13.0V (205μ5ec) 7o, sag (230μ5ec) 40°C Io, 5V (75μ5ec) 9.0v (76μ5ec) 2-D/6. ζV 10. O.V.
ノ, ov (810μ5ec)
(220p 5ec) (75μ5e
c) 1-A 9.5V
lO,OV9. OV(RIFOμ
5ec) (250p 5ec)
(7rμ5ec) Furthermore, the driving temperature margin at 25°C is 2-B ±3. b'C 2-C top 2°6℃ 2-D ±265°C 1-A ±2. L, I-°C.

As is clear from Example 10, even when the device configuration is changed, the device containing the ferroelectric liquid crystal composition 2-B according to the present invention has the same performance as in Example 2 compared to the device containing other liquid crystal compositions. The drive margin is widening, and changes in environmental temperature,
It has an excellent ability to maintain good images despite cell gap variations.

Examples 11-16 Example 1. 5. In place of the exemplary compounds and liquid crystalline compositions used in Example 7, the exemplary compounds and liquid crystalline compositions shown in Table 1 were used in respective parts by weight to obtain a liquid crystalline composition of 11-B-16-B. A ferroelectric liquid crystal device was fabricated in the same manner as in Example 1 except for using these, and the drive margin at 25° C. was measured in the same manner as in Example 1, and the switching state etc. were observed.

Uniform alignment within each liquid crystal element produced was good;
A monodomain state was obtained. The measurement results are shown in Table 1.

v''-+-=-1 As is clear from Examples 11 to 16, the ferroelectric liquid crystal element containing the liquid crystal composition 1O-B-15-B according to the present invention has a wide driving margin and It has an excellent ability to maintain good images against changes in cell gap and variations in cell gap.

〔Effect of the invention〕

The device containing the ferroelectric liquid crystal composition of the present invention has good switching characteristics and a wide drive voltage margin (all pixels can be driven well in matrix even if there is some temperature variation over the display area of the device). A liquid crystal element with a wider driving temperature margin can be obtained.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view of an example of a liquid crystal display element using ferroelectric liquid crystal, and Figures 2 and 3 schematically represent an example of an element cell to explain the operation of a ferroelectric liquid crystal element. A perspective view, FIG. 4 is a waveform diagram of the driving method used in the examples, FIG. 5 is a plan view of a ferroelectric liquid crystal panel in which matrix electrodes are arranged, and FIG. 6 is shown in FIG. 4 (B). Figure 7 is a schematic diagram of the display pattern when actual driving is performed using time-series driving waveforms.
In Figure 1, which shows the change in transmittance when the driving voltage is changed, that is, the V-T characteristic diagram, ferroelectric liquid crystal layer 2...
......Glass substrate 3...
・・・・・・・・・・・・Transparent electrode 4・・・・・・・
...Insulating orientation control layer 5 ......
・・・・・・Spacer 6・・・・・・・・・・・・・・・
・・・・・・Lead wire 7・・・・・・・・・・・・・・・
・・・・・・Power supply 8・・・・・・・・・・・・・・・・・・
・・Polarizing plate 9・・・・・・・・・・・・・・・・
・Light source 1o・・・・・・・・・・・・・・・Incoming light ■・・・・・・・・・・・・・・・・・・Transmitted light In Fig. 2, 21a・・・・・・・・・・・・・・・Substrate 21
b・・・・・・・・・・・・・・・・・・Board in Figure 3, 1a 1b 3a 3b 4a 4b a b Ferroelectric liquid crystal layer Liquid crystal molecule dipole moment (P soil) Voltage application means Voltage application means First stable state Second stable state Upward dipole moment Downward dipole moment Upward electric field Downward electric field

Claims (2)

[Claims] (1) The following general formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (However, R_1 is a linear or branched alkyl group that may have a substituent of C_1 to C_1_8. , R_2
is a linear or branched alkyl group that may have substituents C_1 to C_1_4, X_1 and X_2 are single bonds,
-O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas,
There are chemical formulas, tables, etc. ▼, m is 0 to 7, n is 0 or 1), and at least one of the following general formulas (II) ▲There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) (However, , R_3, R_4 are linear alkyl groups of C_1 to C_1_8, and one CH_2 that does not bond to X_4 in the alkyl group may be replaced with -O-. X_3, X_4 are single bonds , -O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, p, and q are 0, 1, or 2. ) A ferroelectric chiral smectic liquid crystal composition comprising at least one compound represented by the following. (2) The following general formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (However, R_1 is a linear or branched alkyl group that may have a substituent of C_1 to C_1_8. , R_2
is a linear or branched alkyl group that may have substituents C_1 to C_1_4, X_1 and X_2 are single bonds,
-O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas,
There are chemical formulas, tables, etc. ▼, m is 0 to 7, n is 0 or 1), and at least one of the following general formulas (II) ▲There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) (However, , R_3, R_4 are linear alkyl groups of C_1 to C_1_8, and one CH_2 that does not bond to X_4 in the alkyl group may be replaced with -O-. X_3, X_4 are single bonds , -O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, p, and q are 0, 1, or 2. 1. A liquid crystal device comprising: a ferroelectric chiral smectic liquid crystal composition containing at least one compound represented by the following formula: disposed between a pair of electrode substrates.