JPH0224387A - Liquid crystal composition and liquid crystal element containing the same composition - Google Patents

Abstract

PURPOSE:To prepare a liquid crystal element having good switching properties, a wide driving voltage margin, and such a wide driving temp. margin that all picture elements are well matrix driven even when there is some temp. variation on the display area of the element by using a ferroelectric liquid crystal compsn. contg. two specific compds. CONSTITUTION:A liquid crystal element is formed by using a ferroelectric chiral smectic liquid crystal compsn. contg. at least one of the compds. of formula I (wherein R1 and R2 are each 1-18C linear or branched alkyl which may be substd. and at least one of them is optically active; X1 is -O-, formula II, III or IV; and X2 is a single bond, -O-, formula II, III or IV) and at least one of the compds. of formula V (wherein R3 and R4 are each 1-18C linear or branched alkyl which may be substd. by a 1-12C alkoxy group, and are not optically active; X3 and X4 are a single bond, -O-, formula II, III or IV; and m and n are each 0, 1 or 2).

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, W, Helf
Written by r.i.c.h.”Applied Physics
Letters Vo, 18, No. 4 (1971
, 2, 15), P, 127-128 “Voltage
-3pendent 0ptical Activ
ity of a Twisted Nematic
TN (
This uses twisted nematic type liquid crystal.

These are based on the dielectric alignment effect of liquid crystals, and utilize the effect that the average molecular axis direction is oriented in a specific direction due to the dielectric anisotropy of liquid crystal molecules due to an applied electric field. The optical response speed limit of these devices is said to be milliseconds, which is too slow for many applications. On the other hand, for application to large flat displays, driving by a simple matrix method is the most promising in terms of cost, productivity, etc. In the simple matrix method, an electrode configuration is adopted in which a scanning electrode group and a signal electrode group are arranged in a matrix.
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 selected 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 one frame. 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
The more the number of scanning lines increases, the smaller the size becomes, 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, generally used is a ferroelectric liquid crystal having a chiral smectic C phase (SmC) or H phase (SmH'). 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.

85 in FIG. 4(A) is the selection scanning waveform applied to the selected scanning line, SN 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 (Is-5s) are the voltage waveforms applied to the pixels on the selected scanning line, the pixels to which the voltage (ts ss) is applied display black, and the voltage (IN S
The pixel to which S) 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 drive voltage (V5+V+) is changed while keeping the bias ratio, which will be described later, constant.

Here, △t=50μs 1 bias ratio / C'#
It is fixed at r+t;)=1/3. The positive side of Figure 7 is shown in Figure 4 (IN SS), and the negative side is (■8-5S).
) is applied. Here, ■.

v3 are called an actual drive threshold voltage and a crosstalk voltage, respectively. However, V2<V, <V3) and △V=(V3
Vl) is called a voltage margin and is a voltage width that allows matrix drive. V3 is due to FLC matrix drive, -
It can be said that it exists in boat fishing.

Specifically, this is the voltage value that causes switching due to V 8/ in the waveform of FIG. 4(A) (IN-3S). 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. (
do not have. According to our study, a bias ratio of about 1/3 to 1/4 is practical. By the way, if the bias ratio is fixed, the voltage margin ΔV strongly depends on the switching characteristics of the liquid crystal material, and it goes without saying that a liquid crystal material with a large ΔV is very advantageous for matrix driving.

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. Furthermore, the drive margin also changes 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 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, and the driving With a liquid crystal display having a small 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 to solve the problem]

The present invention relates to the following general formula (I) (R11R2 is a linear or branched alkyl group which may have a substituent of 01 to C18, at least one of which is optically active.

Preferred examples of compounds include the following (I-a) to (I-
1) Those shown by the formula can be mentioned.

A small number of compounds represented by the following general formula (I
I) (R3 and R4 represent linear or branched alkyl groups of C1 to CI8. These may have an alkoxy group of 01 to CI2 as a substituent. However, they are non-optically active.

, m and n are 0. I or 2. ) A ferroelectric chiral smectic liquid crystal composition characterized by containing a small amount (or at least one kind) of the compound represented by the above, and a liquid crystal element in which the liquid crystal composition is disposed between a pair of electrode substrates. It is.

Among the compounds represented by the above general formula (I), (S is O
~7, and R5 represents a linear or branched alkyl group) (t is 0 to 7, and R6 represents a linear or branched alkyl group) (R11R2 is as described above) or , and further R in the above formulas (1-a) to (1-1)
More preferable examples of 1°R2 include the following (1-i) to (
1-iii).

(s and t are O to 7, and R, R6 represents a linear or branched alkyl group.) Also, among the compounds represented by the above general formula (II),
Preferred examples of compounds include the following (II-a) to (I
Examples include compounds represented by the formula I-e').

(R3・R4゜X 3 + x4 is as described above) Furthermore, as a more preferable example of x3 and
-i) to (II-viii).

(II-i) (II-ii) (II-iii) (II iv) Gagagaga single bond, single bond, single bond, single bond, X4 is Single bond X4 is 10- X4 is -OC X4 is -CO- (II-v)X3 is -〇-1X4 is a single bond (I
I-vi) X3 is -0-1x4 is 10-(II-vii
) X3 is 10-1X4 is -OC-(II-viii
)
More preferable examples of R4 include (II-iX) to (
II-Xi).

(II ix) R3 is an n-alkyl group.

R4 is an n-alkyl group (p is 0 to 7, R7 is a linear or branched alkyl group) (Hxi) R3 is an n-alkyl group.

CH3 No. R4 is MoCH2. CH(-CH2)r OR8 (q is O-7, r is 0 or l.

R8 represents a linear or branched alkyl group. ) Examples of specific structural formulas of the compounds represented by the general formula (D) are shown below.

n-Cl211250 station o-ecH2}5 aI-t
The compound represented by c2H5 general formula (1) is disclosed in, for example, JP-A-61-200972, JP-A-61-200973,
JP 61-215372, JP 61-291574
It can be obtained by the synthesis method described in et al. For example, it can be obtained by the synthetic route shown below.

R2-X 2+CN A specific structural formula of the liquid crystal compound represented by the general formula (II) is shown below.

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

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

(In the formula, R3, R4, p, and Q are as described above.) A typical synthesis example of the compound represented by the general formula (II) is shown below.

Synthesis Example 1 (Synthesis of compound No. 2-60) 5-methoxyhexanol 1.06 dissolved in pyridine 5mj7
g (8.0 mmol) of p-toluenesulfonic acid chloride dissolved in 5 mA' of pyridine.
(9.6 mmol) was added dropwise at below 5° C. in ice water.

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 give 5-methoxyhexyl-[)
-1” luenesulfonate was obtained.

Dimethylformamide 10mI! 5-decyl-2 (p
-hydroxyphenyl)pyrimidine 2.0g (6,41
mmo1), add 0.61 g of potassium hydroxide, and add 100
Stirred at ℃ for 40 minutes. To this was added the previously obtained 5-methoxyhexyl-p-toluenesulfonate, and the mixture was heated to 100°C.
The mixture was heated and stirred for 4 hours. After the reaction is complete, pour the reaction mixture into cold water.
00mji' 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-1/9), it was recrystallized from hexane to give 5-decyl-2-(4-(5'
-methoxyhexyloxy)phenyl)pyrimidine (compound no.

2-60) 1.35g was obtained.

Phase transition temperature (°C) 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 another liquid crystal compound. It can be obtained by mixing one or more compounds 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.

C8H17 No. 7 10 CH2 Soup Temperature z) Is Ne υ υ υ Each of the liquid crystalline compounds represented by the general formula (1) and the liquid crystalline compound represented by the general formula (II) of the present invention, and one or more of the above-mentioned other liquid crystalline compounds. The alignment ratio of the liquid crystal compound or the ferroelectric liquid crystal composition containing it (hereinafter referred to as ferroelectric liquid crystal material) is based on the general formula (I) of the present invention and the general formula The amount of each of the liquid crystal compounds represented by (II) is preferably 1 to 300 parts by weight, more preferably 5 to 100 parts by weight.

Furthermore, 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. General formula (1) of the present invention per 100 parts by weight
and 1 to 500 parts by weight of a mixture of two or more of one or both of the liquid crystalline compounds represented by general formula (II),
More preferably, the amount is 10 to 100 parts by weight.

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, 1 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゜Sn0.
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 acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin. , an organic insulating material such as melamine resin, Yulia resin, acrylic resin or photoresist resin as an orientation control layer.
The insulating alignment control layer may be formed of two layers, or may be a single layer of an insulating alignment control layer of an inorganic substance or an insulating alignment control layer of an organic substance. If this insulating alignment control layer is inorganic, it can be formed by a vapor deposition method, or if it is organic, it can be formed using a solution in which an organic insulating substance is dissolved or its precursor solution (solvent 0.1 to 20% by weight, preferably 0.5% by weight). 2-10% 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 homogeneous orientation and obtain a monodomain state especially when used as an element, the ferroelectric liquid crystal must be changed from the tomoyoshi phase to the ch phase (cholesteric phase) -3m, A phase (smectic A phase) - It is desirable to have a phase transition series called SmC* phase (chiral smectic C phase).

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 Sm-Tin oxide), between which a liquid crystal molecular layer 22 is oriented perpendicular to the glass surface.
The C heavy phase is filled with smH* phase liquid crystal. 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 equal to or 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 dipole moment (P) 24 is all oriented in the direction of the electric field. The liquid crystal molecules 23 have an elongated shape and exhibit refractive index anisotropy in the long axis direction and the 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 thickness of the liquid crystal cell preferably used in the optical modulation element of the present invention can be made sufficiently thin (for example, 10μ or less).As the liquid crystal layer becomes thinner in this way, as shown in FIG. Even when no electric field is applied, the helical structure of the liquid crystal molecules unravels, and the dipole moment Pa or pb takes either an upward (34a) or downward (34b) state. An electric field Ea or Eb of different polarity above a certain threshold as shown in
is applied by the voltage applying means and 31b, the dipole moment changes direction to upward direction 34a or downward direction 34b corresponding to the electric field vector of the electric field Ea or EJ), and accordingly, the liquid crystal molecules move from the first stable state 33a to the downward direction 34b. Alternatively, it is oriented to either 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. Moreover, FIG. 5 shows a ferroelectric liquid crystal panel 5 in which the matrix electrodes used in the present invention are arranged! FIG. 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, SN is the unselected scanning waveform, 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-3s) and (INSS) 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 pixels to which the voltage (IN-3,) is applied The pixel that has been displayed has 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 t8 phase corresponds to 2Δt. It is set to t.

Now, each parameter vS + of the drive waveform shown in FIG.
The value of vI +Δt is determined by the switching characteristics of the liquid crystal material used. FIG. 7 shows the change in transmittance T when the drive voltage (v5+L) is changed while keeping the bias ratio, which will be described later, constant, that is, the transmittance T is fixed. The positive side of Figure 7 is shown in Figure 4 (IN SS), and the negative side is (I
s Ss) is applied. Here vI,
V3 is called an actual drive threshold voltage and a crosstalk voltage, respectively. However, V2 < Vl < V3) and △v
= (V3 Vl) is called a voltage margin, and is a voltage width that allows matrix drive. It can be said that v3 exists in boat fishing due to the FLC matrix drive. Specifically, V8 in the waveform of FIG. 4(A) (IN Ss)
′ 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 increase flickering and decrease contrast in terms of image quality. Not inviting. According to our study, a bias ratio of about 1/3 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 with a large ΔV 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 (driving voltage margin △■)
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, 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 difference in temperature and cell gap between electrodes) naturally increases ( Therefore, with a liquid crystal having a small driving voltage margin, it is impossible to obtain a good image over the entire display area.The present invention will be explained in more detail with reference to Examples below, but the present invention is limited to these Examples. isn't it.

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

Exemplary compound no.

Structural formula % Formula % Exemplary compounds 16, 2- for this liquid crystal composition 1-A
23 were mixed in the following parts by weight to obtain liquid crystal composition 1-
I got a B.

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

Prepare two 1.1 mm thick glass plates, form an ITO film on each glass plate, create a voltage application electrode,
Furthermore, Si02 was deposited on top of this to form an insulating layer.

Polyimide resin precursor [bundle ■5P-51] is placed on this substrate.
011.0% dimethylacetamide solution at 300 rotations.
It was applied for 15 seconds using an Or, 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.

This fired coating 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. so that they are parallel to each other, and apply adhesive sealant [Rixon Bond (
Glass plates were glued together using Chisso@) and dried by heating at 100°C for 60 minutes to create a cell. The cell thickness of this cell was measured using a Bereck phase plate and was approximately 1
．． It was 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(
Va Va) was measured. The results are shown below. (In addition, Δt is set so that v2 is approximately 15V) 10'0 25℃40℃ Drive voltage merge: / 11.5V 12
．． OV 9.5V (setting Δt during measurement) (
800μ5ec) (230B 5ec) (70
35ec) 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.
It was 0°C.

Further, the contrast during this driving at 25° C. was 9.

Comparative Example 1 Liquid crystal composition 1 in which only exemplary compound No. 1-6 was mixed with 1-A without mixing exemplary compound No. 2-23 of liquid crystal composition 1-H mixed in Example 1. Liquid crystal composition l in which only exemplary compound No. 2-23 was mixed with 1-A without mixing -C and exemplary compound No. 1-6
- Created a new version.

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 1-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 (measurement time △t) 10℃ 2■ 40℃ 1-A 9V 9.5V 8.
5V (1050μ5ec) (280μ5ec)
(78μ5ec) 1-CIOV 10.5
V 9V (900p 5ec) (250
B 5ec) (75p 5ec) 1-D 9
．． 5V 9.5V 8V (900μ5
ec) (250μ5ec) (75μsec
) Furthermore, the driving temperature margin at 25°C is 1-A temperature ±2.2°C, 1-C temperature +2.5°C, and 1-D temperature +2.4°.
It was C.

As is clear from Example 1 and Comparative Example 1, the present invention has an excellent ability to maintain good images against temperature changes and cell gap variations.

Example 2 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 2-B.

Exemplary compound structure formula
Weight part - A A ferroelectric liquid crystal element 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 v-
Thin 12.5V 12.5V 9.5
V (setting Δt during measurement) (750μ5ec) (
230p 5ec) (70p 5ec) 25 more
The driving temperature margin in °C was ±3°3°C.

Also, the contrast during this drive at this temperature is 8
Met.

Comparative Example 2 Among the liquid crystal compositions 2-B mixed in Example 2, Exemplified Compound No. 1-5. Liquid crystal composition 2-C in which only 1-17 was mixed and exemplified compound No. 1-5. Liquid crystal composition 2-D was prepared by mixing only exemplary compound No. 2-57 with l-A without mixing 1-17.

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 (setting △t during measurement) 10℃ 259C40'C 1-A 9V 9.5V 8.
5V (1050μ5ec) (280μ5ec)
(78p 5ec) 2-CIOV IIV
9V (900μ5ec) (250p
5ec) (75B 5ec) 2-D IOV
IOV 8V (900μ5ec)
(250μ5ec) (75μ5ec) Furthermore, the driving temperature margin at 25°C is 1~Ate+2.
2°C, 2-(4'+2.6°C, 2-D +2.4°C).

As is clear from Example 2 and Comparative Example 2, the present invention has an excellent ability to maintain good images against temperature changes and cell gap variations.

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.

Exemplary Compound h Structure Formula % Formula % Furthermore, the driving temperature margin at 25°C is ±3.7°C
Met. Further, the contrast during this drive at this temperature was IO.

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.

Comparative Example 3 Liquid crystal composition 3 in which only exemplary compound No. 1-4 was mixed with 1-A without mixing exemplary compound No. 2-82 of liquid crystal composition 3-B mixed in Example 3. Liquid crystal composition 3 in which only exemplary compound No. 2-82 was mixed with 1-A without mixing -C and exemplary compound No. 1-4
-D was created.

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 3-C and 3-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) lOoC25℃ 40℃ 1-A 9V 9.5V B,
5V (1050p 5ec) (280p 5ec)
(78p 5ec) 3-CIOV I
IV 9V (800μ5ec) (240
p5ec) (75μ5ec) 3-D IO
,5V 11. OV 9.5V (80
0B 5ec) (240μ5ec) (75μ
5ec) Furthermore, the driving temperature margin at 25°C is 1
-A ±2.2℃, 3-C ±2.8℃, 3-D ±2
．． The temperature was 7°C.

As is clear from Example 3 and Comparative Example 3, the ferroelectric liquid crystal element containing the liquid crystal compound 3-B according to the present invention has a wider driving margin and is less susceptible to changes in environmental temperature and variations in cell gap. Image Example 4 Liquid crystal composition 4-B was obtained by mixing the following exemplified compounds in the weight parts shown below with respect to liquid crystal composition 1-A mixed in Example 1.

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 in Ibara.

10°C 25°C 40°C driving voltage v
- Shin 12. OV 12.5V 9.
5V (setting △t during measurement) (8401, tsec)
(220μ5ec) (70μ5ec) 2 more
The driving temperature margin at 5°C was ±3.1°C. Further, the contrast during this driving at this temperature was 9.

Comparative Example 4 Exemplary compound No. 29 was not mixed in the liquid crystal composition 4-B mixed in Example 4, and exemplified compound N was added to 1-A.
Liquid crystal composition 4-C in which only Exemplary Compound No. 1-15 was mixed with Exemplified Compound No. 1-15; Liquid Crystal Composition 4D in which Exemplified Compound No. 2-9 was mixed with 1-A without mixing Exemplified Compound No. 1-15.
It was created.

Instead of using liquid crystal composition 1-B, liquid crystal composition 1-A,
A ferroelectric liquid crystal device was fabricated using the same method as in Example 1, except for injecting 4-C and 4-D into the cell, and the driving voltage margin △V was measured.The results are shown below. show.

Drive voltage margin (measurement setting △t) 10°C 25°C 40'C 1-A 9. OV 9.5V 8
．． 5V (1050μ5ec) (280μ5ec)
(78/Z 5ec) 4-CIo, OV
10. OV 9.0V (900μ5ec)
(250μ5ec) (75p 5ec) 4-D
9. OV 9.5V 8.0V
(900μ5ec) (250μ5ec) (7
5μ5ec) Furthermore, the driving temperature margin at 25℃ is 1-Ate +2.2℃, 4-Cte +2.5℃, 4-D
T? It was +2.4°C.

As is clear from Example 4 and Comparative Example 4, the ferroelectric liquid crystal element containing the liquid crystal compound 4-B according to the present invention has a wider drive margin and is less susceptible to changes in environmental temperature and variations in cell gap. In contrast to Image Example 5, a liquid crystal composition 5-A was prepared by mixing the following parts by weight.

Exemplary compound no.

Structural formula % Formula % Exemplary compounds 1-3 and 2 for this liquid crystal composition 5-A
-73. 2-83 were mixed in the following parts by weight,
Liquid crystal composition 5-B was obtained.

-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 this liquid crystal composition 5-H,
The drive 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 14. OV 14. O.V.
11. OV (Measurement setting △t) (720B
5ec) (230p 5ec) (74p 5
ec) Furthermore, the driving temperature margin at 25°C is ±4
．． The temperature was 1°C. Further, the contrast during this drive at this temperature was 8.

Comparative Example 5 Of the liquid crystal composition 5-B mixed in Example 5, only exemplary compound No. 1-3 was mixed with 5-A without mixing exemplary compound No. 2-73.2-83. 5-A without mixing liquid crystal composition 5-C and exemplified compound No. 1-3
In contrast, liquid crystal composition 5-D was prepared by mixing only side thread compounds No. 2-73 and 2-83.

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 5-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 (setting △t during measurement) 10℃ 25℃ 40℃ 5-A Io, 5V 10.5V
8.5V (1200p 5ec) (330p 5
ec) (98B 5ec)5-C11,OV
11. OV 9.0V (1000μ5e
c) (300μ5ec) (95μ5ec)5
-D 11.5V 11.5V
9.5V (1000p 5ec) (300p 5e
c) (95μ5ec) Furthermore, the driving temperature margin at 25°C is ±2.5°C for 5-A and ±2.5°C for 5-C.
It was ±2.8°C at 7°C and 5-D.

As is clear from Example 5 and Comparative Example 5, the present invention has an excellent ability to maintain good images against changes in power 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.

Exemplary compound fish Structure Formula % Formula % Drive voltage margin 12.5V 12.5V
9. OV (Measurement setting Δt) (1000p
5ec) (300μ5ec) (95μ5e
c) Furthermore, the driving temperature margin at 25°C is ±3.
It was 0°C. Further, the contrast during this driving at this temperature was 9.

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.

Comparative Example 6 Liquid crystal composition 6 in which only exemplary compound No. 1-7 was mixed with 5-A without mixing exemplary compound No. 2-67 of liquid crystal composition 6-B mixed in Example 6. Liquid crystal composition 6 in which only exemplary compound No. 2-67 was mixed with 5-A without mixing -C and exemplary compound No. 1-7
-D was created.

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 10.5V
8.5V (1200μ5ec) (330μ5ec)
(98p 5ec) 6-CIo, 5V
11.5V 8.5V (1000u 5e
c) (300a 5ee) (95μ5ec
)6-D Io, 5V 10.5V
8.0V (1000p 5ec) (300)
(t 5ec) (95μ5ec) Furthermore, the driving temperature margin at 25℃ is ±2.5℃ for 5-A, 6-C
It was ±2.7°C at 6-D, and ±2.6°C at 6-D.

As is clear from Example 6 and Comparative Example 6, the ferroelectric liquid crystal element containing the liquid crystal compound 6-B according to the present invention has a wider driving margin and is less susceptible to changes in environmental temperature and variations in cell gap. Image Example 7 Liquid crystal composition 7-B was obtained by mixing the following exemplified compounds in the weight parts shown below with respect to liquid crystal composition 5-A mixed in Example 5.

Exemplary Compound Magnetic Structure Formula 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 margin 13. OV 13. OV 9.5
V (Measurement setting △t) (850p 5ee)
(260μ5ec) (90μ5ec) Further 25℃
The driving temperature margin was ±3.5°C. Also, the contrast during this drive at this temperature is 10
Met.

Comparative Example 7 Among liquid crystal compositions 7-B mixed in Example 7, only exemplary compounds No. 1-11 and 1-16 were mixed with 5-A without mixing exemplary compound No. 2-21. Liquid crystal composition 7-C and exemplified compounds No. 1-11, 1-16
Exemplary compound No. 2-2 for 5-A without mixing
A liquid crystal composition 7-D was prepared by mixing only 1.

Instead of using liquid crystal composition 7-B, liquid crystal composition 5-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) 106C25℃ 40℃ 5-A Io, 5V 10.5V
8.5V (1200μ5ec) (330μ5e
c) (98p 5ec)7-C11,OV
11.5V 9.0V (1000μ5e
c) (300μ5ec) (90μ5ec)
7-D 11. OV 11. O.V.
9.0V (1000μ5ec) (300μ5
ec) (90μ5ec) Furthermore, the driving temperature margin at 25°C is ±2.5°C for 5-A and ±2.5°C for 7-C.
The temperature was 2.8°C and 2.6°C above 7-D.

As is clear from Example 7 and Comparative Example 7, the ferroelectric liquid crystal element containing the liquid crystal compound 7-B according to the present invention has a wider driving margin, and is less susceptible to changes in environmental temperature and variations in cell gap. In contrast to Image Example 8, a liquid crystal composition 8-A was prepared by mixing the following parts by weight.

Exemplary compound no.

Structural formula For this liquid crystal composition 8-A, exemplified compounds l-4, 1-
19, 2-82, and 2-102 were mixed in the following parts by weight to obtain liquid crystal composition 8-B.

-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 8-H,
The drive 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℃ 45℃ Drive voltage margin 11. OV 11. O.V.
7. OV (setting Δt during measurement) (280μ5
ec) (90p 5ec) (40p 5ec)
) Furthermore, the driving temperature margin at 25°C is 2°7 above.
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, Exemplified Compound No. 2-82.2-102 was not mixed, and Exemplified Compound No. 1-4.1-19 was used for 8-A. Exemplary Compound No. 2-82.8-A was mixed with Exemplified Compound No. 2-82.
A liquid crystal composition 8-D was prepared by mixing only 2-102.

Instead of using liquid crystal composition 1-B, liquid crystal composition 8-A,
A ferroelectric liquid crystal device 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°C 25°C 40°C 8-A 8. OV 8. OV 6
．． 0V (400μ5ec) (110μ5ec)
(40μ5ec)8-C9,OV9. O.V.
6.0V (340p 5ec) (100B
5ec) (40p 5ec) 8-D 9. O
V 9.5V 7.0V (340p 5e
c) (100μ5ec) , (40μ5ec
) Furthermore, the driving temperature margin at 25°C is ±1.9°C for 8-A, ±2.1°C for 8-C, and 2°1°C above for 8-D.
Met.

As is clear from Example 8 and Comparative Example 8, the present invention has an excellent ability to maintain good images against changes in power and variations in cell gap.

Example 9 Liquid crystal composition 8-A mixed in Example 8 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 9-B.

Exemplary Compound Structure Formula % Formula % Drive voltage margin 11.0 11.5V
7.5V (setting at measurement △t) (260μ5e
c) (85μ5ec) (40μ5ec) Furthermore, the driving temperature margin at 25°C was ±2.9°C. Further, the contrast during this driving at this temperature was 10.

A ferroelectric liquid crystal element was produced in the same manner as in Example I except for using this, 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.

Comparative Example 9 Liquid crystal composition 9 in which only exemplary compound No. 1-23 was mixed with 8-A without mixing exemplary compound No. 2-60 of liquid crystal composition 9-B mixed in Example 9. Liquid crystal composition 9 in which only exemplary compound No. 2-60 was mixed with 8-A without mixing -C and exemplary compound No. 1-23
-D was created.

Instead of using liquid crystal composition 1-B, liquid crystal composition 8-A,
A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that 9-C and 9-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°C 25°C 40°C 8-A 8. OV 8. OV 6
．． 0V (400μ5ec) (110μ5ec)
(40p 5ec) 9-C9, OV 9.
5V 6.0V (320μ5ec) (1
00μ5ec) (40μ5ec)9-D 9
．． OV 9. OV 6.0V (320
μ5ec) (100μ5ec) (40p
5ec) Furthermore, the driving temperature margin at 25℃ is 8
-A ±1.9℃, 9-C ±2.3℃, 9-D upper 2
It was 2°C.

As is clear from Example 9 and Comparative Example 9, the ferroelectric liquid crystal element containing the liquid crystal compound 9-B according to the present invention has a wider driving margin, and is less susceptible to changes in environmental temperature and variations in cell gap. It has an excellent ability to maintain good image quality.

Example 10 Liquid crystal composition 8-A mixed in Example 8 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 10-B.

A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except for using the exemplified compound So,
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'C drive voltage margin 12.0 12. OV 8.
5V (Measurement setting △t') (240μ5ec)
(80μ5ec) (40μ5ec) 25 more
The driving temperature margin in °C was ±3.2 °C.

Also, the contrast during this drive at this temperature is 9
Met.

Comparative Example 1O Liquid crystal composition 1 in which only exemplary compound No. 1-6 was mixed with 8-A without mixing exemplary compound No. 2-23 of liquid crystal composition 10-B mixed in Example 10.゜−
Liquid crystal composition 10-D was prepared by mixing only exemplified compound No. 2-23 with 8-A without mixing C and exemplified compound No. 1-6.

Instead of using liquid crystal composition 1-B, liquid crystal composition 8-A,
Except for injecting 10-C and 10-D into the cell, 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 (measurement setting △t) 10℃ 25℃ 40'C3-A 8
．． OV 8. OV 6.0V (400
μ5ec) (110μ5ec) (40μ5
ec) 10-C9, OV 9.5V
7.0V (3001tsec) (100μ5e
c) (40usec) 10-D 9. O.V.
9. OV 6.0V (300μ5e
c) (100μ5ec) (40μ5ec)
Furthermore, the driving temperature margin at 25°C is ±8-A.
1.9℃, 1O-(4'+2.4℃, 10-D ±2.
The temperature was 2°C.

As is clear from Example 10 and Comparative Example 10, the ferroelectric liquid crystal element containing the liquid crystal compound 10-B according to the present invention has a wider driving margin, and is less susceptible to changes in environmental temperature.
Example 11 Regarding variation in cell gap Liquid crystal composition 2-B used in Example 2 and Comparative Example 2.

A ferroelectric liquid crystal element was created in the same manner as in Example 1, except that 2-C, 2-D, and 1-A were created using only polyimide resin without using 5i02. The driving voltage margin was measured in the same manner as in Example 1. The results are shown below.

Drive voltage margin (measurement setting △t) 10°C 25°C 40°C 2-B 14. OV 14. O.V.
10.0V (720μ5ec) (210μ5e
c) (60μ5ec)2-CIo, 5V
11. OV 9.5V (850μ5ec)
(240μ5ec) (75μ5ec) 2-D
lo, OV 10.5V 9.
0V (950p 5ec) (250μ5ec)
(75μ5ec) Further, the driving temperature margin at 25°C was 2-B ±3.8°C, 2-C ±2.7°C, 2-D ±2.7°C, 1-A ±2.4°C.

As is clear from Example 11, 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 that of Example 2 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.

Examples 12 to 19 In place of the exemplified compounds and liquid crystal compositions used in Example 1.5.8, each part by weight of the exemplified compounds and liquid crystal compositions shown in Table 1 was used to prepare 12-B-19-H. A liquid crystalline composition was obtained. 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 created was good;
A monodomain state was obtained. The measurement results are shown in Table 1.

As is clear from Examples 12 to 19, the ferroelectric liquid crystal elements containing liquid crystal compositions 12-B to 19-B according to the present invention have a wide driving margin and are resistant to changes in environmental temperature and variations in cell gap. It has an excellent ability to maintain good image quality.

〔Effect of the invention〕

The device containing the ferroelectric liquid crystal composition of the present invention has good switching characteristics, a large drive voltage margin, and can drive all pixels in a good matrix even if there is a certain degree of temperature variation in the display area of the device. A liquid crystal element with a wide 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 are schematic diagrams of an example of an element cell to explain the operation of a ferroelectric liquid crystal element. 4(A) and 4(B) are waveform diagrams of the driving method used in the examples. FIG. 5 is a plan view of a ferroelectric liquid crystal panel with matrix electrodes arranged. FIG. 7 is a schematic diagram of the display pattern when actual driving is performed using the time-series drive waveform shown in FIG. 4(B).
In Figure 1, which shows the change in transmittance when the driving voltage is changed, that is, the V-T characteristic diagram, l...... 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・・・・・・・・・・・・・・・
Incident light I......Transmitted light In Fig. 2, 21a.........Substrate 1
b 24 ・・・・・・・・・ In Figure 3, 1a 1b 3a 3b 4a 4b a b Substrate ferroelectric liquid crystal layer Liquid crystal molecule dipole moment (on P) Voltage application means Voltage application means 1st stability 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) (R_1 and R_2 are linear or branched alkyl groups that may have substituents of C_1 to C_1_8 and
At least one is optically active. In addition, X_1 indicates -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.▼, and X_2 is a single bond, -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.▼. ) and the following general formula (II) ▲Mathical formula, chemical formula, table, etc. ▼(II) (R_3 and R_4 represent a linear or branched alkyl group of C_1 to C_1_8. These are C_1 as substituents
It may have an alkoxy group of ~C_1_2. However, it is non-optically active. X_3 and 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.▼, m and n are 0
, 1 or 2. ) A ferroelectric chiral smectic liquid crystal composition comprising at least one compound represented by the following formulas. (2) The following general formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (R_1 and R_2 are linear or branched alkyl groups that may have substituents of C_1 to C_1_8 and
At least one is optically active. In addition, X_1 indicates -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.▼, and X_2 is a single bond, -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.▼. ) and the following general formula (II) ▲Mathical formula, chemical formula, table, etc. ▼(II) (R_3 and R_4 represent a linear or branched alkyl group of C_1 to C_1_8. These are C_1 as substituents
It may have an alkoxy group of ~C_1_2. However, it is non-optically active. X_3 and 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.▼, m and n are 0
, 1 or 2. 1.) A liquid crystal element comprising a ferroelectric chiral smectic liquid crystal composition containing at least one compound represented by the following formulas, disposed between a pair of electrode substrates.