JPH0241390A - Liquid crystal composition and liquid crystal element using same - Google Patents

Abstract

PURPOSE:To provide the title novel composition of quick response rate, with the whole picture element capable of favorable matrix driving even under temperature variation on the display area of the element, wide in driving margin, comprising each specific three kinds of liquid crystal compounds. CONSTITUTION:The objective composition can be obtained by formulating each 2-100 pts.wt., per 100 pts.wt. of the final composition, of (A) a compound of formula I [R1 and R2 are each (substituted) 1-16C chain alkyl, one or both of them being optically active; X1 and X2 are each single bond, -O-, etc.], (B) a second compound of formula II [R3 and R4 are each (substituted) 1-16C chain alkyl; X3 and X4 are each single bond, of formula III, etc., Z1, is -O-, -CH2O-, etc.), and (C) a third compound of formula IV (R5 and R6 are each R1; X5 is single bond, of formula V, etc.; X6 is of formula III, V, etc.).

Description

Detailed Description of the Invention [Field of Industrial Application] 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. The present invention relates to a novel liquid crystal composition and a liquid crystal element using the same.

[Prior Art] Liquid crystals have conventionally been applied as electro-optical elements in various fields. Most of the liquid crystal elements currently in practical use are, for example, M-Shut (M.

5chadt) and W Helfrich (W, He1
“Applied Physics Letters” by Frich)
rs'') Vo, 18. No, 4 (197
1, 2, 15) P, 127-128 “Volt
age Dependent Optical Ac
tivity of a Twisted N
This uses a TN (Twisted Nematic) type liquid crystal shown in "Ematic 1quidCrysta+".

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 group of scanning electrodes and a group of signal electrodes are arranged in a matrix, and in order to drive the electrodes, address signals are selectively and periodically applied to the group of scanning electrodes.

A time division driving method is adopted in which a predetermined information signal is selectively applied in parallel to the signal electrode group in synchronization with an address signal.

However, if the above-mentioned N-type liquid crystal is used as an element with such a driving method, there will be a region where the scan electrode is selected and the signal electrode is not selected, or a region where the scan electrode is not selected and the signal electrode is selected (so-called A finite electric field is also applied to the “half-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,
Although the display element operates normally, the number of scanning lines (N
), the time during which an effective electric field is applied to one selected point (duty ratio) while scanning the entire screen (one frame) decreases at a rate of 1/N.

For this reason, when repeated scanning is performed, the effective voltage difference between selected points and non-selected points becomes smaller as the number of scanning lines increases, resulting in a decrease in image contrast and crosstalk. This is a drawback that is difficult to avoid.

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). )
This 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 methods, dual-frequency driving methods, multiple matrix methods, etc. have already been proposed, but all of these methods are insufficient, and it is necessary to increase the screen size of display elements and increase the density. Currently, the number of scanning lines has reached a plateau due to the inability to increase the number of scanning lines sufficiently.

The use of a bistable liquid crystal element is one way to improve these drawbacks of conventional liquid crystal elements.

Clark (C1ark) and Lager (Lager)
wall) (Japanese Patent Application Laid-open No. 107-1983)
No. 216, U.S. Patent No. 4,367,924, etc.)
.

As the bistable liquid crystal, a ferroelectric liquid crystal having a chiral smectic C phase (Sac''' phase) or H phase (SmH'' phase) 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. Also,
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 characteristics of bistability, ferroelectric liquid crystals have the notable characteristic of high-speed response, which is due to the direct interaction between the spontaneous polarization of ferroelectric liquid crystals and the applied electric field. This is to induce state transition, and the response speed is 3 to 4 orders of magnitude faster than the response speed due to the effect of dielectric anisotropy and electric field.

In this way, ferroelectric liquid crystals potentially have extremely excellent properties, and by utilizing these properties, many of the problems of the conventional TN type elements mentioned above can be solved by creating a wood-like liquid crystal. Improvement can be obtained. In particular, it is expected to be applied to high-speed optical shutters and high-density, large-screen displays. For this reason, extensive research has been conducted on liquid crystal materials with ferroelectric properties, but the ferroelectric liquid crystal materials developed to date have sufficient properties for use in liquid crystal devices, including low-temperature operating characteristics and high-speed response. It is hard to say that it has these characteristics.

There exists a relationship between the response time τ, the magnitude of spontaneous polarization Ps, and the viscosity η as expressed by the following formula % (where E is the applied voltage). Therefore, in order to increase the response speed, (a) increase the magnitude of spontaneous polarization Ps (b) viscosity η
There is a method of increasing the applied voltage E to reduce the . The applied electric field has an upper limit because it is driven by an IC or the like, and it is desirable that it be as low as possible.

Therefore, it is actually necessary to reduce the viscosity η or increase the value of the spontaneous polarization Ps.

- For boat fishing In ferroelectric chiral smectic liquid crystal compounds that have large spontaneous polarization, the internal electric field of the cell caused by the spontaneous polarization is also large, and there tends to be more restrictions on device configurations that can take a bistable state.

Moreover, even if the spontaneous polarization is increased unnecessarily, the viscosity tends to increase accordingly, and as a result, it is conceivable that the response speed will not become very fast.

Furthermore, if the actual operating temperature range for a display is, for example, 5 to 40 degrees Celsius, the response speed will generally change by about 20 times, which is currently beyond the limits of adjustment by drive voltage and frequency. be.

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 60 Nos.
Driving methods disclosed in Japanese Patent Laid-open No. 156046-156046, Japanese Patent Application Laid-Open No. 60-156047, etc. can be applied.

FIG. 4 is a waveform diagram of the driving method used in the embodiment of the present invention. 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 ferroelectric liquid crystal 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 arranged between the scanning line 52 and the data line 53 at the intersection. ing.

In FIG. 4(A), Ss indicates the selected scanning waveform applied to the selected scanning line, 8.4 indicates the non-selected scanning waveform, and 1. 1. represents the selection information waveform (black) applied to the selected data line. represents a non-selection information signal (white) applied to an unselected data line. Also, in the figure (1g
-ss) and (1, -S,) are the voltage waveforms applied to the pixels on the selected scanning line, the pixels to which the voltage (ms-3s) 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 I line clear 1. The phase time is set to 2Δt.

Now, each parameter Vs of the drive waveform shown in FIG.
The values of V□ and Δt are 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 (V, +Vl) is changed while keeping the bias ratio, which will be described later, constant. Here, Δt = 501Ls, bias ratio vt/ (vt
+VS) = t/3. The positive side of Figure 7 is shown in Figure 4 (IN-3s), and the negative side is (Is
A waveform indicated by Ss) is applied.

Here, Vl and V3 are called actual drive threshold voltage and crosstalk voltage, respectively, provided that V2<Vl<
V3) Also, ΔV - (V3 - Vl) is called a drive voltage margin, and is a voltage width that allows matrix drive. v3 is F
In terms of driving the LC matrix, it can be said that it exists in boat fishing, and specifically, it is the voltage value that causes switching due to v2 in the waveform of FIG. 4(A) (h-3s). Of course, by increasing the bias ratio, ■3
Although it is possible to increase the value of , increasing the bias ratio means increasing the amplitude of the information signal,
In terms of image quality, this is undesirable as it increases flickering and reduces contrast.

In our study, a bias ratio of about 1/3 to 1/4 was 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 depending on the two directions of the information signal, and unselected pixels can write the "black" or "white" state into the selected pixel. It is possible to maintain the state of The upper and lower limits of the applied voltage and their widths (driving voltage margin ΔV) differ between liquid crystal materials and are unique. Further, 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, 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. If a liquid crystal has a small drive voltage margin, it will not be possible to obtain a good image over the entire display area.

[Problems to be Solved by the Invention] An object of the present invention is to improve the speed of response of a ferroelectric liquid crystal device, reduce its temperature dependence, or expand the driving voltage margin, so that a ferroelectric liquid crystal device can be put to practical use. To provide a chiral smectic liquid crystal composition with a wide driving temperature margin capable of satisfactorily driving all pixels in a matrix even if there is a certain degree of temperature variation in a display area, and a liquid crystal element using the liquid crystal composition.

[Means for Solving the Problems] That is, 1 the present invention provides the following - maximum (I) (wherein R, , R2 are C8 to C8 which may have a substituent)
At least one of the compounds represented by C4 linear or branched alkyl group, at least one of which is optically active *
) R, -X3i Z, +X4- R.

(n) (wherein R3, R, is C which may have a substituent,
~Cta linear or branched alkyl group, X3.
X.

-0C112-, single bond, Beishi ← is baato, bewato, tadago.

-(E), (D-) and at least one of the following compounds (maximum (III)) The present invention will be described in detail below.

Among the compounds represented by the above-mentioned general formula (I), examples of preferable compounds include (I-a) to (I-
p) Compounds represented by the formula are mentioned.

υ (wherein, Ra, R6 is C which may have a substituent
1 to C1, linear or branched alkyl group.

and at least one is optically active.

A ferroelectric chiral smectic liquid crystal composition containing at least one of the compounds represented by
The present invention also provides a liquid crystal element in which the ferroelectric chiral smectic liquid crystal composition is disposed between a pair of electrode substrates.

Further, preferred examples of Rt and Rt in the above formulas (I-a) to (I-p) are (I-i) to (■-t
ri).

-+) R1 is n-alkyl group, R2 is -e H2 CH3) r-CI -R? R,, R, are C1 to C+< linear or branched alkyl groups, and m and n are θ to 7.

Among the compounds represented by the general formula (n), preferred examples include compounds represented by the following formulas (If-a) to (■-k).

R3-X300 X4-R4 (U　-g) Ri-Xa CH, 0-C) X, -R.

Rz-X: + W OCH* + X4-R4(II-
e) (■-f) Furthermore, the above (II-a) X3. As a preferable example of X.

vi).

(■-1) X is a single bond (II-0) X: I is a single bond (■-m) X3 is -〇- (II-iv) X: I is -〇- (ff-v) X3 is 10C- (II-+) in ~(II-k)~(■- x4 is a single bond x4 10- x4 is a single bond x4 is -0- x4 is a single bond (■-vi) X3 is -0C-X, is -0-(II-vi) X3 is -CO-X, is a single bond (n-vi) X3 is -CO-X, is -0- A preferred example of R3.R in formulas II-a) to (II-k) is a linear alkyl group.

Further, as a preferable example of XS,

Further, as more preferable examples of Rs and R6, the following (
m-i) to (m-v) can be mentioned.

°-“゛!...RS is n-alkyl group R6 is one+-CH2)r-
CH-R9R6 is an n-alkyl group R9 to nt2 are linear or branched alkyl groups.

Pe Q+ r+ t represents O~7, s and u represent 0 or l.

Next, an example of a specific structural formula of the compound represented by the above-mentioned -maximum (I) is shown below.

(1-1> Lili (t-SS) υ The compound represented by the above-mentioned maximum (I) is, for example,
1-93170, JP 61-24576, JP 61-129170, JP 61-20
0972, JP 61-200973, JP 61-215372, JP 61-2915
Publication No. 74, East German Patent No. 95892, (1973)
For example, 0 can be obtained by the synthetic route shown below.

R mountain + CN (R1゜ R2゜ x2 means the same as above) next.

Said - Maximum (II) Ingredients of the compound shown in An example of a physical structural formula is shown below.

C3Htic 1120 W QC+ oH21CsH
r 18CI+20 W OC+□1 (25C, H, is) cII20 is) (TOCl 41129C611,1
(Death CI+20c) (to0(co, ÷HC6H++c3
o, -(p needle C1120W Cr, ItI 3CsH+
+ No. CH, 0 is) (Sawa CaH+7Catl+ t+CH
□OW C+Mountain.

C4119 No. C1, Op oc,,u□.

C3+1. +CI+, 0 () ball) C61117C31
1,8c11.0 () (XC, mountain.

C4+19+CHtO→發(ToCaII r tCs1
1++sha0C11□Yu1oc+□H2'5 General formula (n)
A typical synthesis example of the compound represented by is described below.

Synthesis Example 1 (Synthesis of Compound 2-65) (■) 10 g of trans-4-n-propyl cyclohexane chloride (53,6 kg oil)
was dissolved in 30 taR of ethanol, a small amount of triethylamine was added thereto, and the mixture was stirred at room temperature for 10 hours. The reaction mixture was poured into 100 ml of ice water, made acidic by adding 6N aqueous hydrochloric acid solution, and extracted with isopropyl ether. The organic layer was washed with water repeatedly until the washing liquid became neutral, and then dried with magnesium sulfate. After distilling off the solvent, it was purified by silica gel column chromatography and trans-4
9.9 g of -n-propylcyclohexanecarboxylic acid ethyl ester was obtained.

(II) Lithium aluminum hydride 0.73g (
Add 19.1 m OI to 30 p of dry ether,
The mixture was heated under reflux for 1 hour. After cooling to about 10 °C in an ice water bath, trans-4- dissolved in 30 mR of dry ether
5 g (25-5 mmoi') of 〇-propylcyclohexanecarboxylic acid ethyl ester was gradually added dropwise. After the completion of the dropwise addition, the mixture was stirred at room temperature for 1 hour and further heated under reflux for 1 hour. After treating this with ethyl acetate and a 6N aqueous hydrochloric acid solution, it was washed with ice water for 200 lbs! injected into.

After extraction with isopropyl ether, the organic phase was extracted with water,
It was washed successively with an aqueous sodium hydroxide solution and water, and dried over magnesium sulfate. After distilling off the solvent, it was purified by silica gel column chromatography to obtain trans-4-n-
3.5 g of propylcyclohexylmethanol was obtained.

(■) Take 3.4 g of trans-4-n-propylcyclohexylmethanol (22,4+*moi') and dissolve it in zine 2 (lsjJ).To this, add 20tj! of pyridine!
5.3 g of p-toluenesulfonic acid chloride dissolved in
was added dropwise while cooling to below 5°C in an ice water bath. After stirring at room temperature for 10 hours, the mixture was poured into ice water (200 sj). 6
After making the mixture acidic with an aqueous N hydrochloric acid solution, the mixture was extracted with isopropyl ether. The organic phase was washed with water repeatedly until the washing liquid became neutral, and then dried with magnesium sulfate. The solvent was distilled off to obtain trans-4-n-propylcyclohexylmethyl-p-toluenesulfonate.

(IT) 5- to dimethylformamide 4rJtaR
Decyl-2-(4'-hydroxyphenyl)pyrimidine 6,;Ig (20,2ms+oi') was dissolved. Add 1.5 g of 85% potassium hydroxide to this and heat to 100°C.
Stir for hours. To this, 6.9 g of trans-4-n-propylcyclohexylmethyl-p-toluenesulfonate
was added and further stirred at 100° C. for 4 hours. After the reaction was completed, the mixture was poured into 200 mf of ice water and extracted with benzene. After washing the organic phase with water, it was dried with magnesium sulfate. After distilling off the solvent, it was purified by silica gel column chromatography, and further recrystallized from an ethanol/ethyl acetate mixed solvent to obtain the above-mentioned Exemplified Compound No. 2-65.
I got it.

Phase transition temperature ("C) (Sm2 is SmA, smectic phase other than Sac, unidentified) When zl is a single bond, the compound represented by the following formula can be synthesized by the following synthetic route.

IR (cm-”) 2920.2B40, 1608, 1584, 1428,
1258°1164.800 HO shin1υna (R3 and R4 have the same meanings as above) Next, examples of specific structural formulas of the compounds represented by -maximum (m) are described below.

(3-'25) The compound represented by the above general formula (m) is, for example, R50-
o-COO+OR6 can be obtained by the following synthetic route.

(Rs and R6 mean the same thing as above) The liquid crystal composition of the present invention comprises at least one compound represented by the general formula (I) and at least one compound represented by the general formula (II). , and at least one kind of compound represented by the general formula (m) above, in an appropriate ratio.

In addition, 1 liquid crystal composition according to the present invention and other liquid crystal compounds 1
The liquid crystal composition of the present invention may be prepared by further 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.

(1,1) The liquid crystalline compound represented by the general formula (I) of the present invention, the liquid crystalline compound represented by the maximum (II), and the liquid crystalline compound represented by the maximum (II)
The compounding ratio of each of the liquid crystal compounds shown in I) and one or more of the other liquid crystal compounds mentioned above, or a ferroelectric liquid crystal composition containing them (abbreviated as ferroelectric liquid crystal material) is 1 ferroelectric. 1 to 300 parts by weight, more preferably 2 to 100 parts by weight of each of the liquid crystal compounds represented by maximum (1), - maximum (■), and - maximum (m) of the present invention per 100 parts by weight of the liquid crystal material. It is preferable to set it as part.

Also, when using two or more of the liquid crystal compounds represented by the general formula (1), -max (■) and -max (III) of the present invention, the proportion with the ferroelectric liquid crystal material are 1 inventive maximum (I), maximum (II) and maximum (
It is desirable that the amount of any one or a mixture of two or more of the liquid crystal compounds represented by m) be 1 to 500 parts by weight, more preferably 2 to 100 parts by weight.

FIG. 1 is a schematic cross-sectional view showing an example of a liquid crystal element having a ferroelectric liquid crystal layer of 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 InzO:++Sn.
O□Or! TO (indium tin oxide;
A transparent electrode 3 made of a thin film of Tndium Tin Oxide or the like is coated thereon. Thereon, a thin film of a polymer such as polyimide is rubbed with gauze or acetate flocked cloth to form an insulating alignment control layer 4 in which the liquid crystals are aligned in the rubbing direction. Insulating materials such as silicon nitride, hydrogen-containing silicon carbide, silicon oxide, boron nitride, hydrogen-containing boron nitride,
An insulating layer of inorganic material such as cerium oxide, aluminum oxide, zirconium oxide, titanium oxide or magnesium fluoride is formed, and then polyvinyl alcohol, polyimide, polyamideimide, polyesterimide, polyparaxylene, polyester, polycarbonate is formed. , polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, Yulia resin, acrylic resin, photoresist resin, etc. As an orientation control layer, a two-layer insulating orientation control layer can be used. 4 may be formed, or it 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 this insulating orientation control layer is inorganic, it may be formed by a vapor deposition method or the like. If it is an organic type, a solution in which an organic insulating material is dissolved or its precursor solution W1 (0.
1 to 20% by weight, preferably 0.2 to 10% by weight) using a spinner coating method, dip coating method, screen printing method, spray coating method, roll coating method, etc., and under predetermined curing conditions ( For example, under heating), it can be cured and formed.

The thickness of the insulating orientation control layer 4 is usually 30 to IIL11,
Preferably 30 to 3000 people, more preferably 50 people
Approximately 100 people are suitable.

These two glass substrates 2 are kept at an arbitrary distance by a spacer 5. For example, silica beads or alumina beads having a predetermined diameter are sandwiched between the two glass substrates as spacers, and the surroundings are covered with a sealing material 1 such as epoxy. There is a method of sealing using 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 1 in which the ferroelectric liquid crystal is encapsulated generally has a molecular weight of 0.5 to 20 ru, preferably 1 to 5 ru.

In addition, this ferroelectric liquid crystal has an S C''' phase (chiral smectic phase) in a wide temperature range including room temperature (particularly on the low temperature side), and is desirable to have high-speed response. It is desired that the dependence be small and that the driving voltage margin be wide.

In addition, in order to obtain a monodomain state exhibiting good uniform alignment, especially when used as an element, the ferroelectric liquid crystal has to be changed from the isoyoshi phase to the ch phase (cholesteric phase)-5sA phase (smectic phase)-3ac' It is desirable to have a phase transition series called "" 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 transmission type, so it 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
In, 03. respectively. SnO or ITO (In
This is a substrate (glass plate) covered with a transparent electrode made of a thin film such as dium-tin oxide), between which a liquid crystal molecular layer 22 is oriented perpendicular to the glass surface.
C8 phase or SmH" phase liquid crystal is sealed. Two thick lines represent liquid crystal molecules, and this liquid crystal molecule 23 has a dipole moment (P) in the direction perpendicular to the molecule.
A) It has 24. When a voltage higher than a certain threshold is applied between the electrodes on the substrates 21a and 21b, the liquid crystal molecules 2
The helical structure of 3 unravels and the dipole moment (PA)
The alignment direction of the liquid crystal molecules 23 can be changed so that all of the liquid crystal molecules 24 are 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, for example, if crossed Nicol polarizers are placed above and below the glass surface, the voltage application polarity can be changed. It is easily understood that the liquid crystal optical modulation element has optical characteristics that change depending on the amount of the liquid crystal.

The liquid crystal cell preferably used in the optical modulation element of the present invention has a sufficiently thin thickness (for example, 10 IL or less).
As the liquid crystal layer becomes thinner, the helical structure of the liquid crystal molecules unwinds even in the absence of an applied electric field, as shown in Figure 3, and the dipole moment Pa or pb is directed upward (34a). ) or downward (:+
Either state 4b) is taken. In such a cell, an electric field Ea of different polarity above a certain threshold value is applied as shown in FIG.
Alternatively, when Eb is applied by the voltage applying means 31a and 31b, the dipole moment changes its direction to upward direction 34a or downward direction 34b corresponding to the electric field vector of electric field Ea or Eb, and accordingly, the liquid crystal molecules become first stable. Status $33a
or the second stable state 33b.

As mentioned earlier, there are two advantages to using such a ferroelectric liquid crystal element as an optical modulation element.

The first is that the response speed is extremely fast, and the second is that the orientation of the liquid crystal molecules suppresses bistability. To further explain the second point, for example with reference to FIG. 3, the electric field Ea
When the voltage is applied, the liquid crystal molecules are aligned in a first stable state 33a, and this state remains stable even when the electric field is turned off. Moreover, when an electric field Eb in the opposite direction is applied, the liquid crystal molecules enter the second stable state $
33b and changes the orientation of the molecule, but it remains in this state even after the electric field is turned off. Further, as long as the applied electric field Ea or Eb does not exceed a certain threshold value, the previous orientation state is maintained.

When a ferroelectric liquid crystal material having such characteristics is used as a simple matrix display device using an element sandwiched between a pair of substrates, for example, Japanese Patent Laid-Open Nos. 59-193426 and 5
Driving methods disclosed in JP-A No. 9-193427, JP-A-60-156046, JP-A-60-156047, etc. 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 ferroelectric liquid crystal 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 arranged between the scanning line 52 and the data line 53 at the intersection. ing.

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 ■8 is the selection information waveform applied to the selected data line ( (black), and ■o represents a non-selection information signal (white) applied to an unselected data line. Also, in the figure (Is-
s, ) and Nx-5s) are the voltage waveforms applied to pixels on the selected scanning line; pixels to which voltage (Is Ss) is applied display black, and pixels to which voltage (IN-ss) is applied display black. The pixel that has been detected 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; The phase time is set to 2Δt.

Now, each parameter V of the drive waveform shown in FIG.
The values of V, , Δt are 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+vr) is changed while keeping the bias ratio, which will be described later, constant. Here, Δt = 50gs, bias ratio right/(VX+V
g) is fixed at = l/3. The positive side in Figure 7 is H shown in Figure 4, -5s), and the negative side is (Is-Ss
) is applied.

Here, Vl and V3 are called the actual drive threshold voltage and crosstalk voltage, respectively, where Vz<Vl<Vi, and ΔV = (V3-Vl) is called the drive voltage margin, which is the voltage width that allows matrix drive. becomes. v:l is FLC
Due to the matrix drive of - it can be said that it exists in boat fishing.
Specifically, this is the voltage value that causes switching due to vl in the waveform of FIG. 4(A) (Ls-3li). Of course, by increasing the bias ratio, vl
Although it is possible to increase the value of 1, increasing the bias ratio means increasing the amplitude of the information signal.
In terms of image quality, this is undesirable as it increases flickering and reduces contrast.

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 constant temperature, the circuit writes the two states of "black" and "white" to the selected pixel depending on the two directions of the information signal, and the non-selected pixels write the "black" or "white" state to the selected pixel. ” state can be maintained. The upper and lower limits of the applied voltage and their widths (driving voltage margin ΔV) differ between liquid crystal materials and are unique. Further, 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, 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. If the liquid crystal has a small voltage margin, it will not be possible to obtain a good image over the entire display area.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 The following exemplified compounds were mixed in the following parts by weight to prepare liquid crystal composition 1.
-A was created.

Exemplary compound Jio.

Structural formula Exemplary compound l　2 Exemplary compound -A Structural formula Structural formula Weight part Exemplary compound No.

Structural Formula Further, the following exemplified compounds were mixed with the liquid crystal composition 1-A in the weight parts shown below to prepare a liquid crystal composition 1-B.

Parts by weight Next, using a cell prepared from this liquid crystal composition 1-B according to the following procedure, device characteristics etc. were observed.

Two glass plates with a thickness of 1.1 mm were prepared, an ITO film was formed on each glass plate, a voltage application electrode was created, and 5ins was further vapor-deposited thereon to form an insulating layer.

On this substrate, a polyimide resin precursor [manufactured by Bunrei, SP-
710) A 1.0% dimethylacetamide solution was applied for 15 seconds using a spinner with a rotation speed of 2500 r, p, m. 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 approximately 200.

This fired coating was rubbed with acetate flocked cloth, then washed with isopropyl alcohol solution, and silica beads with an average particle size of 1.51 Lm were sprinkled on one glass plate, and each rubbed axis The glass plates were glued together using an adhesive sealant (manufactured by Chisso ■, Rixon Pond) so that they were parallel to each other, and heated and dried at 100° C. for 60 minutes to create a cell. When the cell thickness of this cell was measured using a Berek phase plate, it was found that
It was approximately 1.5#L1.

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

Using this ferroelectric liquid crystal element, a drive voltage margin ΔV is obtained using the drive waveform (113 bias) shown in FIG.
(V, -V,) was measured.

In addition, the pulse width Δt set at the time of measurement is the drive threshold voltage L=20
It was set to be V. At this time, ΔV+=20V
) is the drive threshold voltage pulse width, which indicates the response speed.

10℃ 25℃ Drive voltage margin ΔV 13.5V 14. O.V.
(Measurement setting (620 (220 pulse width Δt)
) psec) ) zsec) 40°C 12.4V interval 5ec) Further, when 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) was 4° 1"C above.

Further, the contrast during driving at 25° C. was 12.

Comparative Example 1 Instead of liquid crystal composition 1-H used in Example 1, exemplified compound No. 1-16.1-47 was not mixed, and exemplified compound No. 2-12 was used for 1-A. .2-25.2-1
A liquid crystal prepared by mixing only 06, 3-56 in the same weight parts as in Example 1! I-forming acid compound-c, and exemplified compound No. 2-12
, 1 to 1-A without mixing 2-25.2-106
Liquid crystal composition 1-D in which only Exemplified Compound No. 1-16.1-47.3-56 was mixed in the same weight part as in Example 1; -A
For example compound No. 1-16.1-47.2-
A liquid crystal composition 1-E was prepared by mixing only 12.2-25°2-106 in the same weight parts as in Example 1.

These liquid crystal compositions 1-C, 1-D, 1-E and 1-A
A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that a ferroelectric liquid crystal element was used, and a driving voltage margin ΔV and a driving temperature margin at 25° C. were measured in the same manner as in Example 1. The results are shown below.

Drive voltage margin ΔV (゛Set pulse width Δt during measurement) lO℃ 25℃ 1-A 9. OV 9.0
V (890 pot 5ec) (248 interval 5ec) 40℃ 9.0■ (92 adjacent 5ec) 1-C11,3V 11. sV
9.5V' (700μ5ec) (240 end 5ec) (90 mackerel 5ee) -D 10.5V 10.5V
8.5V (730μ5ec) (240Psec)
(85sec) -E 12, OV ll0V 11
．． 3V (6704sec) (2:15psec
) (85 psec) Drive temperature margin 1-A ± 1.6°C t-C ± 268°C 1-D Upper 2°3°C 1-E ± 3. :l@C As is clear from Example 1 and Comparative Example 1, the ferroelectric liquid crystal element having the liquid crystal composition according to the present invention has a wider driving margin, and is less susceptible to changes in environmental temperature and variations in cell gap. On the other hand, it has an excellent ability to maintain good images.

Furthermore, when focusing on the pulse width Δt set at the time of measurement, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a higher
The temperature dependence of response speed is also reduced.

Example 2 Liquid crystal composition 1-A used in Example 1 was mixed with 1 part of 1M of the following exemplified compounds to obtain liquid crystal composition 2-B.

Exemplary compound No.

Structural Formula A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that this liquid crystal composition was used, and the driving voltage 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 excellent, and a monodomain state was obtained. The measurement results are shown below.

Driving voltage margin ΔV (Pulse width Δt set during measurement) 10°C 25'C 40°C Driving voltage merge: / A V l: 1. OV 1
:1. OV 11.5V (setting during measurement (4)
70 (170 (70 pulse width Δt) psec)
psec) psec) Furthermore, the driving temperature margin at 25°C was ±3.9°C.

Also, the contrast during this drive at 25°C is I
It was 3.

Comparative Example 2 Instead of liquid crystal composition 2-B used in Example 2, exemplified compound No. 1-21 was used for l-A without mixing exemplified compound No. 2-76, 2-99. .3-15.3-3
Liquid crystal composition 2 in which only 7 was mixed in the same weight part as in Example 2
-C was created.

Except for using these liquid crystal compositions 2-C and 1-A, ferroelectric liquid crystal elements were prepared in the same manner as in Example 1, and the driving voltage margin ΔV and The driving temperature margin at 25°C was measured. The results are shown below.

Drive voltage margin ΔV (pulse width Δt set during measurement) 10°C 25'C 40°C 1-A 9. OV 9. O.V.
7.8V (890gsec) (2484sec)
(92 psec) 2-ClO, 5V 1
0.2V 9.0V (580psec)
(1804 sec) (65 psec) Driving temperature margin 1-A ± 3.9'C As is clear from Example 2 and Comparative Example 2, the ferroelectric liquid crystal element having the liquid crystal composition according to the present invention has a higher driving margin. It has an excellent ability to maintain good images even with changes in environmental temperature and variations in cell gap.

Furthermore, when focusing on the pulse width Δt set at the time of measurement, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a higher
The temperature dependence of response speed is also reduced.

Example 3 Liquid crystal composition 1-A used in Example 1 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 3-8.

2-C±2.1'C Exemplary compound 2-1O No.

Structural Formula A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that this liquid crystal composition was used, and the driving voltage 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.

Drive voltage margin ΔV (Pulse width Δt set during measurement) lOoo 25 °C 40 °C Drive voltage margin ΔV 13.5V 13.8V 12.7
VA Further, the driving temperature margin at 25°C was ±4.1°C.

Also, the contrast during this drive at 25°C is 1
It was 4.

Comparative Example 3 In place of liquid crystal composition 3-H used in Example 3, exemplified compound No. 1-17 was added to l-A without mixing exemplified compound No. 2-10.2-36. .1-48.3-4
Liquid crystal composition 3 in which only 0 was mixed in the same weight part as in Example 3
-C was created.

Ferroelectric liquid crystal elements were prepared in the same manner as in Example 1, except that liquid crystal compositions 3-C and 1-A were used, and driving voltage margins ΔV and The driving temperature margin at 25°C was measured. The results are shown below.

Drive voltage margin ΔV (pulse width Δt set during measurement) 10°C 25°C 40°C 1-A 9. OV 9. O.V.
7.8V (890gsec) (248gsec)
(92esec)3-C11,5V 1
2. OV 9.5V (740psec)
(245 gsec) (904 sec) Driving temperature margin 1-A ±4-1@c As is clear from Example 3 and Comparative Example 3, the driving margin of the ferroelectric liquid crystal element having the liquid crystal composition according to the present invention is better. It has excellent balance to maintain good images even with changes in environmental temperature and variations in cell gap.

Further, when focusing on the III fixed time setting and the pulse width Δt, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a reduced temperature dependence of the response speed.

Example 4 The following exemplified compounds were mixed in the following parts by weight to prepare liquid crystal composition 4.
-A was created.

3-C±2.8℃ Exemplary compound No.

Structural formula Structural formula Exemplary compound No.

Structural formula Structural formula Furthermore, For this liquid crystal composition 4-A, less than The exemplary compounds shown are Mixed in the weight parts shown below. death, Liquid crystal composition 4-B was created.

-A Part by weight Part by weight A ferroelectric liquid crystal element was prepared in the same manner as in Example 1 except that this liquid crystal composition was used, and the driving voltage margin was measured in the same manner as in Example 1. 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.

Drive voltage margin ΔV (all regular setting pulse width Δ) lOoC25℃ 40℃ Drive voltage merge: / A V 14.8V 15
．． IV 13. OV (setting during measurement (800
(280(110 pulse width Δt) psec)
gsec) gsec) Furthermore, the driving temperature margin at 25° C. was 4° C. above.

Also, the contrast during this drive at 25°C is 1
It was 2.

Comparative Example 4 Instead of liquid crystal composition 4-H used in Example 4, exemplified compound No. 1-16.1-47 was not mixed, and exemplified compound No. 2-12 was used for 4-A. .2-25.2-1
Liquid crystal composition 4-C2 in which only No. 06, 3-56 was mixed in the same parts by weight as in Example 4 and exemplified compound No. 2-12,
Liquid crystal composition 4 in which only exemplary compound No. 1-16.1-47.3-56 was mixed in the same weight part as in Example 4 with respect to 4-A without mixing 2-25.2-i06. -D, and 4-A without further mixing exemplified compound No. 3-56, exemplified compound No. 1-16.1-47.2-12.
Liquid crystal composition 4-E was prepared by mixing only 2-25.2-106 in the same weight parts as in Example 4.

These liquid crystal compositions 4-C, 4-D, 4-E and 4-A
A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that a ferroelectric liquid crystal element was used, and a driving voltage margin ΔV and a driving temperature margin at 25° C. were measured in the same manner as in Example 1. The results are shown below.

Drive voltage margin ΔV (IJA regular setting pulse width Δt) 10℃ 25'C 4-A Io, 0V 10.5V (115
0 psec) (320 psec) 40 °C 8,0v (114 psec) -C 11,7V 12.0V (910 psec) (:105 psec)11,
Mouth V (115gsec) -D 11, OV 11.5V
9.5V (930gsec) (315gsec
) (110gsec)-E 13, OV 13.3V 1
2.0V (880μ5ec) (:100ALse
c) (110 gsec) Driving temperature margin 4-A ± 1.6°C 4-C ± 2.9°C 4-D Upper 2°5°C 4-E ± 3.2°C From Example 4 and Comparative Example 4 As is clear, the ferroelectric liquid crystal element having the liquid crystal composition according to the present invention has a wider driving margin and is superior in its ability to maintain good images against changes in environmental temperature and variations in cell gap. There is.

Furthermore, when focusing on the pulse width ΔE set at the time of measurement, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a higher
The temperature dependence of response speed is also reduced.

Example 5 Liquid crystal composition 4-A used in Example 4 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 5-B.

Exemplary compound No.

Structural Formula A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that this liquid crystal composition was used, and the driving voltage 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.

Drive voltage margin ΔV (Pulse width Δt set during measurement) 106C25℃ 40℃ Drive voltage margin A V 14. :IV 14.
7V 12.6V-A Also, the driving temperature margin at 25°C is 4°1°C above.
Met.

Also, the contrast during this drive at 25°C is 1
It was 3.

Comparative Example 5 In place of liquid crystal composition 5-H used in Example 5, exemplified compound No. 1-3.1-45.3-4.3-24 was added to 4-A without mixing. , a liquid crystal composition S-C in which only Exemplified Compound No. 2-11 was mixed in the same parts by weight as in Example 5.
It was created.

Except for using these liquid crystal compositions 5-C and 4-A, ferroelectric liquid crystal elements were prepared in the same manner as in Example 1, and in fact, in the same manner as in Example 1, the driving voltage margin Δ ,■
, and the driving temperature margin at 25°C. The results are shown below.

Drive voltage margin ΔV (I regular setting pulse width Δt) 10'c 25℃ 40℃ 4-A 1O-OV 10.5V
8.0V (1150μ5ec) (3204s
ec) (114 psec) 5-C11, OV
11. :IV 10.7V(
965μ5ec) (310gsec) (1
10gsec) Driving temperature margin 4-A ± 1.6°C 2°3°C above 5-C As is clear from Example 5 and Comparative Example 5, the ferroelectric liquid crystal element having the liquid crystal composition according to the present invention The drive margin is wide, and the ability to maintain good images despite changes in environmental temperature and variations in cell gap is excellent.

Furthermore, when focusing on the pulse width Δt set at the time of measurement, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a higher
The temperature dependence of response speed is also reduced.

Example 6 Liquid crystal composition 4-A used in Example 4 was mixed with the exemplified compounds shown below in the fflii L portion shown below to obtain liquid crystal composition 6-B.

Exemplary compound No.

Structural Formula Ferroelectric liquid crystal elements were prepared in the same manner as in Example 1 except that this liquid crystal composition was used, and the driving voltage margin was measured in the same manner as in Example 1 and the switching state etc. was observed. did. The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

Drive voltage margin ΔV (set pulse width Δ during measurement) lOoC25"C4G"C Drive voltage margin ΔV 14. OV 14.4V
13. OV (Measurement setting (620 (22)
0 (85 pulse width Δt) psec) IL
sec) gsec) Furthermore, the driving temperature margin at 25°C was ±4.2°C.

Also, the contrast during this drive at 25°C is 1
It was 3.

Comparative Example 6 Instead of liquid crystal composition 6-B used in Example 6, Exemplified Compound No. 2-65.2-70.3-41 was not mixed, and Exemplified Compound No. 2-65.2-70.3-41 was used for 4-A. 1-55.1-67
Liquid crystal composition 6- in which the same weight parts as in Example 6 were mixed with
Created C.

Except for using these liquid crystal compositions 6-C and 4-A, ferroelectric liquid crystal elements were prepared in the same manner as in Example 1, and the driving voltage margin ΔV and The driving temperature margin at 25°C was measured. The results are shown below.

Drive voltage margin ΔV (0 regular setting pulse width Δt) 10°C 25°C 40°C 4-A lO,OV 10.5V
8.0V (l150μ5ec) (320μ5ec
) (114μ5ec)6-CI2. O.V.
11.7V 11. :IV(70
0gsec) (2304sec) (804
sec) Driving temperature margin 4-A ± 1.6°C As is clear from Example 6 and Comparative Example 6, the driving margin of the ferroelectric liquid crystal element having the liquid crystal composition according to the present invention is wider, and the environmental It has an excellent ability to maintain good images despite temperature changes and cell gap variations.

Furthermore, when focusing on the pulse width Δt set at the time of measurement, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a higher
The temperature dependence of response speed is also reduced.

Example 7 The following exemplified compounds were mixed in the following parts by weight to prepare liquid crystal composition 7.
-A was created.

6-C±2.4℃ Exemplary compound No.

Structural formula Structural formula Exemplary compound No.

Structural formula I created the liquid crystal set 7-8.

Exemplary compound No.

Structural formula For this liquid crystal composition 7-A, less than The exemplified compounds are shown below.

A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that this liquid crystal composition was mixed in the following parts by weight. The voltage margin was measured and the switching status etc. were observed. The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The J11 fixed fruit is shown below.

Drive voltage margin ΔV (Pulse width Δt set during measurement) 10°C 25°C 40°C Drive voltage margin A V 12.8V 13.7V 121
V (setting during measurement (425 (150 (55 pulse width Δt) 5ee) end 5ec) 5
ee) Furthermore, the driving temperature margin at 25°C was 3° to 8°C.

Also, the contrast during this drive at 25°C is 1
It was 4.

Comparative Example 7 In place of liquid crystal composition 7-B used in Example 7, 1 exemplified compound No., 1-:l, 1-45 was not mixed, and 7-A was used.
For example compound No. 2-11.3-4.3-2
Liquid crystal composition 7 in which only 4 was mixed in the same weight part as in Example 7
-C was created.

Except for using these liquid crystal compositions 7-C and 7-A, ferroelectric liquid crystal elements were prepared in the same manner as in Example 1, and the driving voltage margin ΔV and The driving temperature margin at 25°C was measured. The results are shown below.

Drive voltage margin ΔV (set pulse width Δ during measurement) 10℃ 2S”C40℃ 7-A 9.OV 9.
5V 8.0V (536 psec)
(160gsec) (62psec)7-C11
,OV 11. OV 10.
5V (490psec) (165psec)
(60 psec) Driving temperature margin 7-A Upper 2°1°C 7-C±2.6°C As is clear from Example 7 and Comparative Example 7, the ferroelectric liquid crystal element having the liquid crystal composition according to the present invention However, the drive margin is widened, and the ability to maintain good images despite changes in environmental temperature and variations in cell gap is excellent.

Furthermore, when focusing on the pulse width Δt set at the time of measurement, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a higher
The temperature dependence of response speed is also reduced.

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

Exemplary compound no.

Structural formula % Formula % A ferroelectric liquid crystal element was prepared in the same manner as in Example 1 except that this liquid crystal composition was used, and the driving voltage margin was measured in the same manner as in Example 1. observed. The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

Drive voltage margin ΔV (Pulse width Δt set during measurement) 10”C25℃ 40℃ Drive voltage margin ΔV 13.:IV 13.9
V 12.8V Also, the driving temperature margin at 25°C was ±4.3°C.

Also, the contrast during this drive at 25°C is 1
It was 4.

Comparative Example 8 In place of liquid crystal composition 8-H used in Example 8, exemplary compound No. 1-13.1-:lO,2-33,2-62
Exemplary compound No. 3-A was added to 7-A without mixing.
Liquid crystal composition 8-C was prepared by mixing only No. 22 in the same weight parts as in Example 8.

Except for using these liquid crystal compositions 8-C and 7-A, ferroelectric liquid crystal elements were prepared in the same manner as in Example 1, and the driving voltage margin ΔV and The driving temperature margin at 25°C was measured. The results are shown below.

Drive voltage margin ΔV (pulse width Δt set during measurement) 10°C 25°C 40°C 7-A 9. OV9.5V
a, 0V (536 psec) (160 psec)
(62psec)8-C9,5V IQ
, :IV 8.7V (490gsec)
(160 psec) (55 sec) Driving temperature margin 7-A Upper 2°1"C 3-C±2.2°C As is clear from Example 8 and Comparative Example 8, ferroelectricity with the liquid crystal composition according to the present invention Liquid crystal elements have a wider drive margin and are better able to maintain good images despite changes in environmental temperature and variations in cell gap.

Furthermore, when focusing on the pulse width Δ set at the time of measurement, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a higher
The temperature dependence of response speed is also reduced.

Examples 9 to 16 In place of the exemplified compounds and liquid crystal compositions used in Example 1, the exemplified compounds and liquid crystal compositions shown in Table 1 were used in respective parts by weight, and the liquid crystal of 9-B-16-B was prepared. A sexual composition was obtained. Except for using these, a ferroelectric liquid crystal element was created in the same manner as in Example 1, the driving voltage margin was measured in the same manner as in Example 1, and the switching state, etc. was observed. The uniform alignment within the liquid crystal element is good.

A monodomain state was obtained. The measurement results are shown in Table 1.

As is clear from Examples 9 to I6, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention has a wider driving margin, and the performance of one image against changes in environmental temperature and variations in cell gap is greater. Excellent ability to keep it in good condition.

Furthermore, when focusing on the pulse intensity Δt set at the time of measurement, the ferroelectric liquid crystal element containing the liquid crystal composition according to the present invention also has reduced temperature dependence of response speed.

Example 17 The liquid crystal composition used in Example 1 and Comparative Example 1 was
A ferroelectric liquid crystal element was created in the same manner as in Example 1, except that the alignment control layer was created only with polyimide resin without using The switching status 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.

Drive voltage margin ΔV (pulse intensity Δt set during measurement) 10@C25℃ 1-B 14. IV 14.4V (595
psec) (2154sec) 1-A 9.
5V 9.8V (870μ5ec) (24
0μ5ec) 1-C11,7V 12.0V (680 end 5ee) (230 end 5ee) 1-D
11. OV 11.0V (710ILsec
) (2254sec) 1-E 12.5V
13.3V (655 end 5ee) (225 end 5ee)
ec) Driving temperature margin 1-B Upper 4°4°C 1-A tl, 8”c l-C Upper 3°0°C I-D Upper 2°5°C 1-E Upper 3°5°C 40°C 12. 7V (9 (lμ5ec) 8, OV (90psec) 10, OV (90μ5ec) 9.2V (85μ5ec) 11.5V (85 end sec) As is clear from Example 17, even when the element configuration is changed, this The element having the ferroelectric liquid crystal composition according to the invention has a wider driving margin than elements having other liquid crystal compositions, as in Example 1, and the performance of one image due to changes in environmental temperature and variations in cell gap. It has an excellent ability to keep it in good condition.

Furthermore, when focusing on the pulse intensity ΔL set at the time of measurement, the ferroelectric liquid crystal element having the liquid crystal composition according to the present invention has a reduced temperature dependence of the response speed.

[Effects of the Invention] The ferroelectric liquid crystal composition according to the present invention and the liquid crystal element containing the same have good switching characteristics, a large driving voltage margin, and a certain degree of temperature variation over the display area of the element. Also, it is possible to obtain a liquid crystal element with a wide driving temperature margin in which all pixels can be satisfactorily matrix-driven, and a liquid crystal element with reduced temperature dependence of response speed.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing an example of a liquid crystal device using the ferroelectric liquid crystal layer of the present invention, and FIGS. 2 and 3 show an example of an element cell for explaining the operation of the ferroelectric liquid crystal device. 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. The figure is Figure 4 (B)
FIG. 7 is a schematic diagram of a display pattern when actual driving is performed using the time-series drive waveform shown in FIG. 1... Ferroelectric liquid crystal layer 2... Glass substrate 3...
Transparent electrode 4... Insulating alignment control layer 5... Spacer 6... Lead wire 7... Power supply
8...Polarizing plate 9...Light source I.・・・
・Incoming light ■...Transmitted light 21a--1 substrate 21b-...Substrate 22...
- Liquid crystal molecule layer 23... Liquid crystal molecules 24... Dipole moment (P↓) 31a, 31b - Voltage application means 3: la = first stable state 33b... second stable state 34a. ...Upward dipole moment 34b--Downward dipole moment Ea---Upward electric field E b--Downward electric field

Claims (2)

[Claims] (1) The following general formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R_1 and R_2 are C which may have a substituent.
It is a linear or branched alkyl group of _1 to C_1_8, and at least one of them is optically active. X_1,
X_2 is a single bond, -O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas,
There are chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼) At least one of the compounds represented by the following general formula (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ( II) (In the formula, R_3 and R_4 are C which may have a substituent
_1 to C_1_8 linear or branched alkyl group,
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.▼,
Z_1 is -O-, -CH_2O-, -OCH_2-, single bond, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
There are tables, etc. ▼ is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼
, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , ▲ Mathematical formulas, chemical formulas, There are tables, etc. ▼, but ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ mathematical formulas, chemical formulas,
At least one of ▼ has tables, etc. is ▲ has mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ has mathematical formulas, chemical formulas, tables, etc. ▼) and at least one of the compounds represented by the following general formula (III) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(III) (In the formula, R_5 and R_6 are C which may have a substituent.
It is a linear or branched alkyl group of _1 to C_1_8, and at least one of them is optically active. X_5 is a single bond, -O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas,
There are chemical formulas, tables, etc. ▼, X_6 is a single bond, -O-,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
A ferroelectric chiral smectic liquid crystal composition characterized by containing at least one of the compounds shown in the table below (indicated by ▼). (2) The following general formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R_1 and R_2 are C which may have a substituent.
It is a linear or branched alkyl group of _1 to C_1_8, and at least one of them is optically active. X_1,
X_2 is a single bond, -O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas,
There are chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼) At least one of the compounds represented by the following general formula (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ( II) (In the formula, R_3 and R_4 are C which may have a substituent
_1 to C_1_8 linear or branched alkyl group,
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.▼,
Z_1 is -O-, -CH_2O-, -OCH_2-, single bond, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
There are tables, etc. ▼ is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼
, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , ▲ Mathematical formulas, chemical formulas, There are tables, etc. ▼, but ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ mathematical formulas, chemical formulas,
At least one of ▼ has tables, etc. is ▲ has mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ has mathematical formulas, chemical formulas, tables, etc. ▼) and at least one of the compounds represented by the following general formula (III) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(III) (In the formula, R_5 and R_6 are C which may have a substituent.
It is a linear or branched alkyl group of _1 to C_1_8, and at least one of them is optically active. X_5 is a single bond, -O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas,
There are chemical formulas, tables, etc. ▼, X_6 is a single bond, -O-,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
1. A liquid crystal element characterized in that a ferroelectric chiral smectic liquid crystal composition containing at least one of the compounds shown in Table 1 (indicated by ▼) is disposed between a pair of electrode substrates.