JPH0317074A - Liquid crystalline compound, liquid crystal composition containing the same and liquid crystal element using the same - Google Patents

Abstract

NEW MATERIAL:A liquid crystal compound of formula I [R1 and R2 are 1-18C alkyl wherein one or non-neighboring two or more CH2 groups in the alkyl groups may be substituted with Z, ZC(=O), C(=O)Z, CO, CH=CH, C=C, etc., and at least one of the alkyl groups is optically active; A is A1, A1-A2 (A1 and A2 are groups of formula II-VII)]. EXAMPLE:2-sec-Butyl-5-(4'-decyloxyphenyl)-1,3,4-thidiazole. USE:A component for liquid crystal compositions providing liquid crystal elements having good switching characteristics and improved low temperature actuating characteristics and further liquid crystal elements having the reduced temperature dependency of response speeds thereof. When used for display methods utilizing AC stabilizing effects, the compound can highly improve the display characteristics. PREPARATION:For example, the compound of formula I is prepared by the reactions according to the reaction scheme.

Description

[Detailed Description of the Invention] [Prior Art] A ferroelectric liquid crystal display system, SSFLC (Surf
ace-Stabilized-ferroele
In the liquid crystal (ctric-liquid crystal) method, the helical pitch l of the ferroelectric liquid crystal (hereinafter referred to as FLC) itself. The main focus is to solve the problem using the effects of the upper and lower substrate interfaces.

■ Adjust the distance between the upper and lower substrates (cell thickness) to the helical bit 1. (2) Furthermore, if the liquid crystal molecules are set to be oriented parallel to the substrate interface, the layer direction in the smectic phase of the FLC is formed perpendicular to the substrate.

(2) Furthermore, by regulating the orientation direction of molecules on at least one substrate, it is possible to maintain a constant layer direction over the entire surface of the cell.

If we look at the alignment state formed by the stepwise molecular control described above from a macroscopic perspective, we can see that FLC is stable within the cell plane.
The long axis direction (n) of the molecule is limited to two directions. The FLC display attempts to apply these two directions to the display element.

The basic mechanism for stably switching between two directions as described above utilizes the ferroelectricity exhibited by FLC in the smectic C* phase.

FLC has a molecular dieball moment (μ) in a plane parallel to the layers, and the dipole moment (μ) is continuously connected between the cell substrates even though the direction changes slightly.
On average, spontaneous polarization (Ps) exists from the lower substrate to the upper substrate or vice versa.

Since each of the directions A of spontaneous polarization (Ps) (from top to bottom or from bottom to top) coincides with one of the long axes (n) of the molecules described above, switching by an electric field is possible.

Specifically, when an electric field is applied to the FLC layer from the outside, the die ball moment (μ) in the layer is all aligned in the direction of the electric field (Ul), and when the electric field is turned off, it relaxes for a while and becomes (1μ).
s to 2 m s, depending on the FLC) (Sl). U1 has a higher degree of molecular order than SL and is optically in a state of good uniaxiality (uniform state), whereas St has inferior axiality than U1 (twisted state) because the FLC die ball is somewhat twisted, but it is spontaneous. This is a state in which the directions of polarization match. Similarly, if the polarity of the external electric field is reversed, states U2 and S2 exist. Sl
, S2, it is possible to select between the two states Ul and U2 by changing the polarity of the electric field.

A typical ferroelectric liquid crystal cell has an IT structure on a glass substrate.
Form an electrode pattern with O, etc., and form a short-circuit prevention layer for the upper and lower substrates with Si02, etc. on top of it (approximately 1000 people).On top of that, form a PI (Toray: SP510, 710,...) film with approximately 400 people. The PI film is shaped by the film thickness, and the PI film is rubbed with a flocked cloth such as acetate, and then the PI film is arranged vertically symmetrically, and the substrate spacing is set to l~
The thickness was kept at 3 μm.

It is known that FLC arranged under such conditions generally connects the A substrates with the director in a twisted state, and does not exhibit uniaxial orientation in the smectic C phase (Sl, S2 described above). . One of the problems in such a case is that the transmittance of the liquid crystal layer is low.

Optical sorting between stable two-state SL, 32 is carried out by setting a polarizer in a crossed nicol state and inserting the cell described above between them. When aligned with the absorption axis of , the amount of transmitted light becomes significantly lower, making it possible to express "black".

Next, when switching the molecular position to the S2 state, S
If the angle between t and 52 is 2θa, at 82, the molecule position is shifted by 2θa from the polarization axis to generate transmitted light and express “white”.

Assuming that the molecular orientation is uniaxial, the amount of transmitted light has an intensity of I relative to the intensity of the incident light I0 under crossed Nicol conditions.

A Here, Δn is the refractive index anisotropy of FLC, d is the cell thickness, and λ
is the wavelength of the incident light.

It has been experimentally known that when a cell as described above is used and a twisted orientation is taken, θa is 5° to 8° and does not depend much on the abrasive material.

Since the term Δndπ/λ cannot be easily controlled due to physical properties, we would like to increase θa to increase I, but
Depending on the static orientation technique, it is difficult to achieve all the precepts well.

For such problems, it is known that θa can be expanded by using the torque of the Δε term of FLC (
Published by AT&↑゛ in 1983.8 ID, Canon JP-A No. 61-24514.2, No. 61-246722,
61-246723, 61-246724, 61-
249024, 61-249025). By applying an electric field with a constant effective value other than during switching, the stable state of molecules in the electric field changes from Sl and S2 due to the generation of dielectric polarization (AC stabilization effect). The torque r'ps acting on the FLC molecule regarding the switching of F
The torque rΔε acting on the LC molecules is proportional to the following physical properties.

rps” Ps・E・・・・・・・ (2) FΔ1
QC -Δε◆ε.・E2・・・・・・(3)
As is clear from equation (3), the sign and absolute value of Δε of FLC play a very important role.

V of four types of FLC with different values of physical properties regarding Δε
FIG. 4 shows the change in θa with respect to r m s.

The measurement was performed at 60 KHz to eliminate the influence of Ps.
It was done with a rectangular exchange.

(I) is Δε2-5.5, (II) is Δε2-3.0,
(DI) is Δε20, (rV) is Δε21.0, and qualitatively Δε is (1) < (II) < (
III) < (IV).

As can be seen from the graph, the more negative Δε becomes, the larger θa becomes at low voltage, and therefore, it can be seen that it contributes to ■.

Comparing the difference in transmittance when using (I) and (III), there was a clear difference between 15% for (I) and 6% for (m).

As is known from the above examples, the display characteristics of SSFLC can be greatly changed by controlling the physical properties of Δε and Ps(η).

However, most of the currently used ferroelectric liquid crystal compositions have a Δε almost close to 0, so that it is hardly expected that the display characteristics will be improved by the AC stabilizing effect described above.

On the other hand, the current liquid crystal compositions containing at least one liquid crystal compound having a negative Δε and having a large negative Δε have a drawback of poor response characteristics.

OBJECT OF THE INVENTION] An object of the present invention is to solve the above-mentioned problems, namely:
The present invention provides a liquid crystal composition that has excellent response characteristics and can provide an AC stabilizing effect by using a novel liquid crystal compound having a negative Δε, and a liquid crystal element using the liquid crystal composition.

[Means and effects for achieving the object] The present invention is based on the following general formula (1): It is an alkyl group, and one or more non-adjacent methylene groups in the alkyl group may be present.However, 2 represents 101 or -S-, and R3 is H or an alkyl group having 1 to 5 carbon atoms. Indicates a group.Furthermore, R1, R2
At least one of them is optically active. Also, A is -A, -
-A, -A2-, where A, , A2 represent a liquid crystal compound, a ferroelectric smectic liquid crystal composition containing at least one of the liquid crystal compounds, and a pair of liquid crystal compositions. The present invention provides a liquid crystal element arranged between electrode substrates.

In the liquid crystalline compound represented by the general formula, Rl, R2
is preferably selected from i) to iii) below.

i) n-alkyl group having 1 to 18 carbon atoms, represented by the general formula (
A general synthesis example of the liquid crystalline compound represented by 1) is shown below.

R, -COC2H5 R, -CNHNH2 (However, m is an integer of 0 to 7, and n is an integer of 2 to 9. Also, it may be optically active.) CH3 ■ iii) {=CH23 -rCH-f-CHz}sO
ctHzt++ (where r is an integer from 0 to 7, S
is 0 or 1. Further, t is an integer from 1 to 14.

It may also be optically active. ) However, RI+
At least one of R2 is optically active.

H, w to No A-R2 Or, -CH2 adjacent to A in R2 -CH2 1101R 2-A-COC 2H l5 R 2-A-CNHNH 2 If found, it is possible to leave. The hydroxyl group or carpoxyl group present in A is protected with a protecting group, and the protecting group is removed after the ring is closed to a thiadiazole ring (However, R R 2 + A is as described above.) The general formula (I) The specific structural formula of the liquid crystalline compound represented by (l) is shown below.

(l (l (l (l (l (l +2) (t-is) (l (l (l (l (l +2) (t-is) (l (l (l (l (l (l.-47) (l U (+-61) (l (l (!) (l (l (l (l (l))) It can be obtained by mixing at least one liquid crystal compound represented by formula (I) and one or more other liquid crystal compounds in an appropriate ratio.

Further, the liquid crystal composition according to the present invention is a ferroelectric liquid crystal composition,
In particular, ferroelectric smectic liquid crystal compositions are preferred.

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

Compound no. O O CM, CH3 CH3 CH3 O CH3 CH3 CH3 O CH3 CH3 CH3 O O CH3 CH3 U U CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 c 8H ,70-@-@- CH 20 -@-o-
+ CH 2}- 3 0HOC 5H ,,* CH3 CH3 CH3 U CH3 CH3 CH3 CH3 RI O CI Cl O Cl Cl Cl Cl Cl Cl! U O (J' Br O Br FF C 8H ,, 0-@-@-CH 20 -@-CH
2 0CH 2 CHC ,oH ,,* F O F ○ F O F F F F O F F ○ F F F O F F F O F F CF3 CF3 FF CN CN C 5 H 11 sound ■C6Hl3 (2+1) O O O O O O ri O O c , 2H 215 o-@-c} { 2of Sawa OC6
H13 The liquid crystal compound of the present invention and one or more other liquid crystal compounds, or a liquid crystal composition containing the same (these may be ferroelectric liquid crystal compounds and ferroelectric liquid crystal compositions. Below , these are abbreviated as liquid crystal materials).The compounding ratio of the liquid crystal compound according to the present invention is preferably 1 to 500 parts by weight per 100 parts by weight of the liquid crystal material.

In addition, when using two or more types of liquid crystal compounds of the present invention, the blending ratio with the liquid crystal material is 1 of the mixture of two or more types of liquid crystal compounds of the present invention per 100 parts by weight of the above-mentioned liquid crystal material.
It is preferable to set it as 500 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 are made of In203 and SnO, respectively.
2 or ITO (Indium-Tin Ox
A transparent electrode formed from a thin film such as IDE) 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. Examples of insulating materials include silicon nitride, hydrogen-containing silicon carbide, silicon oxide, boron nitride, hydrogen-containing boron nitride, cerium oxide, aluminum oxide,
Form an inorganic insulating layer such as zirconium oxide, titanium oxide or magnesium fluoride, and then apply polyvinyl alcohol, polyimide, polyamideimide, polyesterimide, polyparaxylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride,
An insulating orientation control layer may be formed of two layers using an organic insulating material such as polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, Yulia resin, acrylic resin, or photoresist resin as the orientation control layer,
Alternatively, it may be a single layer of an insulating orientation control layer made of an inorganic material or an insulating orientation control layer of an organic material. If this insulating orientation 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 containing an organic insulating material or its precursor solution (
0.1 to 20% by weight (preferably 0.2 to 10% by weight) in a solvent and applied by a spinner coating method, dip coating method, screen printing method, spray coating method, roll coating method, etc. It can be cured and formed under curing conditions (eg, under heat).

The layer thickness of the insulating orientation control layer is usually 30 to 1 μm, preferably 30 to 3,000 μm, and more preferably 50 to 1 μm.
000 people is suitable.

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

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

The ferroelectric liquid crystal layer in which the ferroelectric liquid is encapsulated generally has a thickness of 0.5 to 20 tlm, preferably 1 to 5 μm.

Further, it is desirable that this ferroelectric liquid crystal has an SmC* phase (chiral smectic C phase) in a wide temperature range including room temperature (particularly on the low temperature side) and has high-speed response. Furthermore, it is desired that the temperature dependence of the response speed be small and that the driving voltage margin be wide.

In addition, especially when used as a device, in order to exhibit good homogeneity and obtain a monodomain state, the ferroelectric liquid crystal has to change from isophase to ch phase (cholesteric phase) - S m A phase (
It is desirable to have a phase transition series of smectic A phase)-SmC wood 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 2lb are respectively In203, Sn02 or ITO (Indiu
A substrate (glass plate) coated with a transparent electrode made of a thin film such as m-Tin Oxide, etc., between which a liquid crystal molecular layer 22 is oriented perpendicular to the glass surface.
or SmH* phase liquid crystal is enclosed. A thick line 23 represents a liquid crystal molecule, and this liquid crystal molecule 2
3 is the dipole moment (P±
)24. When a voltage higher than a certain threshold is applied between the electrodes on the substrates 21a and 21b, the helical structure of the liquid crystal molecules 23 is unraveled, and the liquid crystal molecules 23 are aligned so that all the dipole moments (P±) 24 are directed in the direction of the electric field. You can change direction. 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 liquid crystal cell preferably used in the optical modulation element of the present invention can have a sufficiently thin thickness (for example, 10 μm or less). As the liquid crystal layer becomes thinner in this way, the helical structure of the liquid crystal molecules unwinds even when no electric field is applied, as shown in Figure 3, and the dipole moment Pa or pb is directed upward (34a) or downward (34b). ). When an electric field Ea or Eb of different polarity above a certain threshold value is applied to such a cell by the voltage applying means 31a and 3lb as shown in FIG. 3, the dipole moment corresponds to the electric field vector of the electric field Ea or Eb. Then, the liquid crystal molecules change their direction to upward direction 34a or downward direction 34b, and accordingly, the liquid crystal molecules enter either the first stable state 33a or the second stable state.
is oriented in one of the stable states 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. Moreover, when an electric field Eb in the opposite direction is applied, the liquid crystal molecules enter the second stable state 3.
3b and changes the orientation of the molecule, but it remains in this state even after the electric field is turned off. Also, unless the applied electric field Ea or Eb exceeds a certain threshold value, the previous orientation state is maintained.

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited to these Examples.

Example I 2-sea-butyl-5-(4' monodecyloxyphenyl)-1.3.4-thiadiazole (Exemplary Compound NC
Production of L 1-1 1) i) vii) i) Synthesis of 2-methylbutanoic acid 2-methylbutanol 50.0g (5.68
0-'mol), KMnO 4 130g (8.23
X 10-'mol) KOH 15g, water 250
0 ml was placed in a 51 reaction vessel and stirred at room temperature for 2 hours. After the reaction, wash with ether (500ml x 3)
After that, conc. The mixture was acidified with HCl and extracted with chloroform (500 mI!X3). After drying the anhydrous magnesium sulfate, the solvent was distilled off to obtain 45.0 g of crude product. This was distilled under normal pressure to obtain 37.3 g of 2-methylbutanoic acid. (Yield 64.4%, b, pl61-162.
5°C) ii) Synthesis of 2-methylbutanoic acid chloride or 37.0 g (3.63 x 10-'mol) of 2-methylbutanoic acid
) and 173.0 g (1.45 mol) of thionyl chloride were placed in a 300 mj' reaction vessel and stirred at room temperature for 6 hours. The reaction mixture was distilled under normal pressure to obtain 20.0 g of 2-methylbutanoic acid chloride. (Yield 45.7%) iii) Ethyl p-anisate 150 g (8.33 x 10-
'mol), ethanol 300mj? was added to a 1 liter reaction vessel at room temperature under stirring with 80% hydrazine hydrate.
g (4.83 mol) was added.

Thereafter, the mixture was heated to 60° C. in an oil bath and reacted for 20 hours.

After the reaction was completed, the mixture was poured into 1.5 II' of ice water, and the precipitated crystals were recrystallized from ethanol to obtain 88.2 g of anisohydrazide. (Yield 63.8%) iv) N-anisoyl-N'-2-methylbutanoylhydrazineanisohydrazide 22.1g (1,33X10-'m
ol) Dry pyridine 217mj! was heated to 40°C, and while stirring, 16.0 g of 2-methylbutanoic acid chloride was added.
(1.33X10-1 mol) 75 ml of dry benzene
solution was added dropwise over 30 minutes. Then at 40℃
The reaction was allowed to proceed for 6 hours.

After the reaction was completed, only benzene was distilled off and used in the next step without further treatment.

v) 2-sec-butyl-5-anisyl-1.3.4-
Thiadiazole N-anisoyl-N'-2-methylbutanoylhydrazine was placed in a 500 ml reaction vessel, and 38.4 g (l., 73X 10-'mo+) of phosphorus pentasulfide was added over 15 minutes while stirring at room temperature. Thereafter, the mixture was heated to 100°C in an oil tank and reacted for 5 hours.

After the reaction, ethanol/water = 1/20 (ethanol 5
0 ml, water 1ffi) and extracted with chloroform (7
After washing with water (700 ml x 2) and drying over anhydrous magnesium sulfate, the solvent was distilled off to obtain 49.0 g of a crude product.

This was purified using a silica gel column using chloroform/ethyl acetate = 3/1 to obtain 21.0 g of 2-sec-butyl-5-anisyl-1,3,4-thiadiazole.

vi) 2-see-butyl-5-(4'-hydroxyphenyl)-1.3.4-thiadiazole combination 2-s
ec-butyl-5-anisyl-1.3.4-thiadiazole 20g (8.06 X 10-2mo+), HB
200 g of r (acetic acid solution) was placed in a 300 ml reaction vessel, heated to 100° C. in an oil bath, and reacted for 50 hours while blowing HBr gas. Furthermore, Hl
100 mj' was added and reacted at 100°C for 1 hour and 30 minutes.

After the reaction was completed, it was poured into water 11 and extracted with chloroform (l
I! After washing with water (II!X4) and drying over anhydrous magnesium sulfate, the solvent was distilled off to obtain 9.0 g of crude product.

This was subjected to silica gel ram filtration using chloroform/ethyl acetate=371 to obtain 5.9 g.

Furthermore, decolorization was performed using activated carbon, and 2-sec-butyl-5-(4'-hydroxyphenyl)-1.3.4
- 5.0 g of thiadiazole was obtained. (Yield 26.5%)
vii) Synthesis of 2-sec-butyl-5-(4'-monodecyloxyphenyl)-1.3.4-thiadiazole 2-sec-butyl-5-(4'-hydroxyphenyl)-1.3.4- Thiadiazole 0.5g (
2.14 mmol) in dimethylformamide 20 mA'
It was dissolved in Add 85% KOHO to this. 1 4
g (2.14 mm o + ) was added thereto, and the mixture was heated and stirred at 100° C. for 1 hour in an oil bath. To this was added 0.57 g (2.14 mmol) of n-decyl iodide, and the mixture was further heated at 100°C for 5 hours. After the reaction was completed, the reaction solution was poured into 100 ml of water and extracted with ethyl acetate (50r+1×2). After washing with water (100mfX2),
It was dried over anhydrous magnesium sulfate and the solvent was distilled off to obtain a crude product. This was subjected to silica gel column chromatography (
Purified with developing solution toluene/ethyl acetate = 2/1),
Further, it was recrystallized from ethanol to give 2-sec-1-butyl-5-(4'-1-decyloxyphenyl)-1,3,4
-0.16 g of thiadiazole was obtained. (Yield 20%) I
R (cm-1) 2940, 2860, 1612, 1466, 14481
258.1182,844 Example 2 The following exemplified compounds were mixed in the following parts by weight to prepare liquid crystal composition A.
It was created.

Exemplary compound no. Structural formula Weight part Phase transition temperature ('C) Exemplary compound No. Structural Formula Weight Parts 13 F U Further, the following exemplary compounds were mixed with the liquid crystal composition A in the weight parts shown below to prepare a liquid crystal composition B.

Exemplary compound no. Structural formula Weight part FU A Next, two glass plates with a thickness of 0.7 mm were prepared, an ITO film was formed on each glass plate, a voltage application electrode was created, and SiO 2 was vapor-deposited to form an insulating layer. A silane coupling agent [KBM-602 manufactured by Shin-Etsu Chemical ■] 0.2% isobrobyl alcohol solution was applied onto a glass plate at a rotational speed of 200 or so. p. The surface treatment was carried out by applying it for 15 seconds using a No. m svinner.

Thereafter, a heat drying treatment was performed at 120° C. for 20 minutes.

Furthermore, 1.5% polyimide resin precursor [Toray @ SP-510] was applied on a glass plate with an ITO film that was surface-treated.
The dimethylacetamide solution was rotated at 200 rpm. p. m
It was applied for 15 seconds using a tinner. After film formation, for 60 minutes,
A heating condensation firing treatment was performed at 300°C. The thickness of the coating film at this time was approximately 250.

The fired coating was rubbed with acetate flocked cloth, then washed with isopropyl alcohol solution, and alumina beads with an average particle size of 2 μm were sprinkled on one glass plate. Glue the glass plates together so that they are parallel to each other using adhesive sealant [Rixon Pond (Chitsuso ■)], and leave for 60 minutes.
A cell was prepared by heating and drying at 100°C. The cell thickness of this cell was measured using a Bereck phase plate and was approximately 2 μm.
Met.

By injecting liquid crystal composition B in an isotropic liquid state into this cell and slowly cooling it from the isotropic phase to 25°C at a rate of 20°C/h,
A ferroelectric liquid crystal device was created.

Using this ferroelectric liquid crystal element, the optical response (transmitted light amount change 0 to 90%) under crossed Nicols is detected by applying a voltage of peak-to-peak voltage Vpp = 20V, and the response speed (hereinafter referred to as optical response) is detected. speed) was measured.

The results are shown below.

15℃ 25℃ 35℃Response speed 130μsec 91μsec
78 μsec Comparative Example 2 A ferroelectric liquid crystal element was prepared in the same manner as in Example 2 except that one drop of liquid crystal composition A mixed in Example 2 was injected into the cell, and the optical response speed was measured.

The results are shown below.

15℃ 25℃ 35℃ Response speed 155 μsec 100 p sec
80 p sec Example 3 Exemplary compounds 1-3 and 1-6 used in Example 2.
In place of 1-46, the following exemplified compounds were mixed in the weight parts shown below to prepare liquid crystal composition C.

Exemplary compound no. Structural formula Weight parts 1-11 1-17 1-88 A 9J A ferroelectric liquid crystal element was prepared in the same manner as in Example 2 except that this liquid crystal composite was used. The optical response speed was measured using the method described above.

The measurement results are shown below.

l5°C 25°C 35°C Response speed 120 μsec 81 usee 70 μsec Example 4 Exemplary compounds 1-3 and 1-6 used in Example 2.
Liquid crystal composition D was prepared by mixing the following exemplified compounds in the weight parts shown below in place of 1-46.

Exemplary compound no. Structural formula Weight parts 1-37 A A ferroelectric liquid crystal element was prepared in the same manner as in Example 2 except that this liquid crystal composition was used, and the optical response speed was measured in the same manner as in Example 2. .

The measurement results are shown below.

l5°C 25°C 35°C Response speed 119 μsec 83 μsec 69 μsec Example 5 Exemplary compound 1-3 used in Example 2, ! -6.
In place of 1-46, the following exemplified compounds were mixed in the weight parts shown below to prepare liquid crystal composition E.

Exemplary compound no. Structural formula Parts by weight 1-24 1-59 A A ferroelectric liquid crystal element was prepared in the same manner as in Example 2 except that this liquid crystal composition was used, and the optical response speed was determined in the same manner as in Example 2. was measured.

The measurement results are shown below.

Example 6 The following exemplified compounds were mixed in the following parts by weight to prepare liquid crystal composition F.
was created.

Exemplary compound no. Structural formula Weight part 15°C 25°C 35°C Response speed 134 μsec 90 μsec 78 μsec Exemplary compound No. Structural formula Parts by weight Furthermore, the following exemplary compounds were mixed with the liquid crystal composition F in the weight parts shown below to prepare a liquid crystal composition G.

Exemplary compound no. Structural formula Weight part U 1-32 F A ferroelectric liquid crystal element was prepared in the same manner as in Example 2 except that this liquid crystal composition was used, and the optical response speed was measured in the same manner as in Example 2. 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.

15℃ 25℃ 35℃ Response speed 350 μsec 227 μ
sec 178 μsec Comparative Example 6 A ferroelectric liquid crystal device was prepared in the same manner as in Example 2 except that the liquid crystal composition F mixed in Example 6 was injected into the cell, and the optical response speed was measured.

The results are shown below.

l5℃ 25℃ 35℃ Response speed 450 μsec 270 μ
sec 195 μsec Example 7 Exemplary Compounds 1-10 used in Example 6. 1-32
．． In place of 1-63.1-82, the following exemplified compounds were mixed in the weight parts shown below to prepare liquid crystal composition H.

Exemplary compound no. Structural formula Parts by weight 1-36 UF A ferroelectric liquid crystal element was prepared in the same manner as in Example 2 except that this liquid crystal composition was used, and the optical response speed was measured in the same manner as in Example 2. The switching state, etc., were observed.

The homogeneity within this liquid crystal element was good, and a monodomain state was obtained.

The measurement results are shown below.

15℃ 25℃ 35℃ Response speed 355 μsec 237 μ
sec 186 μsec Also, clear switching behavior was observed during driving, and good bistability was observed when voltage application was stopped.

Example 8 Exemplary compounds used in Example 6! -10, l-32.
In place of 1-63 and 1-82, the following exemplified compounds were mixed in the weight parts shown below to prepare liquid crystal composition I.

Exemplary compound no. Structural formula Weight part U F 9l A ferroelectric liquid crystal element was prepared in the same manner as in Example 2 except that this liquid crystal assembly was used, and the optical response speed was measured in the same manner as in Example 2. , switching state, etc. were observed.

The homogeneity within this liquid crystal element was good, and a monodomain state was obtained.

The measurement results are shown below.

15℃ 25℃ 35℃ Response speed 383 p see 241
usee 187 μSeC Also, clear switching behavior was observed during driving, and good bistability was observed when voltage application was stopped.

Example 9 Exemplary compounds 1-10 used in Example 6, l. -3
In place of 2.1-63.1-82, the following exemplified compounds were mixed in the weight parts shown below to prepare liquid crystal composition J.

Exemplary compound no. Structural formula Weight part F 9l A ferroelectric liquid crystal element was produced in the same manner as in Example 2 except that this liquid crystal composition was used, and the optical response speed was measured in the same manner as in Example 2. The switching status etc. were observed.

The homogeneity within this liquid crystal element was good, and a monodomain state was obtained.

The measurement results are shown below.

15°C 25°C 35°C Response speed 369 p sec 240 μsec
191 μsec Also, clear switching behavior was observed during driving, and good bistability was observed when voltage application was stopped.

Example 10 Liquid crystal CS-101 manufactured by Chisso Corporation where Δε is almost 0.
4 [Δε% − 0.4 (sin wave, 100KHz
)) and the exemplified compounds shown below were mixed in the parts by weight shown below to prepare liquid crystal composition K.

Exemplary compound no. Structural formula Weight part! -13 U CS-1014 Using this liquid crystal composition, a ferroelectric liquid crystal element was produced in exactly the same manner as in Example 2, except that the liquid crystal layer thickness was 1.5 μm.

Using the liquid element described above, the tilt angle was measured at 25° C. under crossed Nicols conditions. Next, microscopic observation was performed while applying a square wave of ±8 V at a frequency of 60 KHz, and the tilt angle was measured. Also, the transmittance at this time was measured. moreover,
Contrast ratio was also measured.

The results are shown below.

Orthogonal Nicols lower Tilt angle application lower Tilt angle l/Transmittance no l Contrast ratio CS-1014 Liquid crystal assembly K'7c'7.4° 8.8° 13.8° 7.8% 12.5% 8 : 1 44 : 1 Example 11 Chisso liquid crystal CS-1014 with Δε almost 0
[Δe −− − 0.4 (sin wave, 1 0
0 KHz)] and the exemplified compounds shown below were mixed in the parts by weight shown below to prepare a liquid crystal composition L.

Exemplary compound no. Structural formula Weight part l-27 From the above, CS-1014 whose Δε is almost O
It was found that the display characteristics of a liquid crystal element obtained by mixing the liquid crystal compound of the present invention with the liquid crystal compound of the present invention can be improved due to the AC stabilizing effect.

CS-1014 9l Using this liquid crystal composition, a ferroelectric liquid crystal element was produced in the same manner as in Example 2, except that the liquid crystal layer thickness was 1.5 μm.

Using the above liquid crystal element, the tilt angle was measured under crossed Nicols conditions at 25°C. Then ±8v at a frequency of 60KHz
Microscopic observation was performed while applying a rectangular wave of , and the tilt angle was measured. Also, the transmittance at this time was measured. Furthermore, the contrast ratio was also measured.

The results are shown below.

Below crossed Nicols Tilt angle application Below Tilt angle Transmittance Contrast ratio CS-1014 Liquid crystal composition L 767.2° 8.8° 11.9° 7.8% lO. 5% 8:1 32:1 Example 12 Chisso liquid crystal CS-1014 with Δε almost 0
[Δεz-0.4 (sin wave, loOKHz)] and the exemplified compounds shown below were mixed in the parts by weight shown below,
A liquid crystal composition M was prepared.

Exemplary compound no. Structural formula Weight part l-60 CS-1014 whose Δε is almost O
It was found that the display characteristics of a liquid crystal element obtained by mixing the liquid crystal compound of the present invention with the liquid crystal compound of the present invention can be improved due to the AC stabilizing effect.

CS-1014 A ferroelectric liquid crystal element was prepared using this liquid crystal composition in the same manner as in Example 2, except that the liquid crystal layer thickness was 1.5 μm.

Using the above liquid crystal element, the tilt angle was measured under crossed Nicols conditions at 25°C. Next, microscopic observation was performed while applying a square wave of ±8 V at a frequency of 60 KHz, and the tilt angle was measured. Also, the transmittance at this time was measured. moreover,
Contrast ratio was also measured.

The results are shown below.

Orthogonal Nicol lower Tilt angle application lower Tilt angle // Transmittance // Contrast ratio CS-1014 Liquid crystal composition M 7° 7.3° 8.8° 10.5° 7.8% 9.8% 8: 1 28:1 Example 13 Liquid crystal CS-1014 manufactured by Chisso Corporation in which Δε is almost O
[Δe2-0.4 (sin wave, 100KHz)]
and the exemplified compounds shown below were mixed in the parts by weight shown below to prepare a liquid crystal composition N.

Exemplary compound no. Structural formula CS-10 whose Δε is almost O due to the weight part or more
It was found that the display characteristics of a liquid crystal element obtained by mixing No. 14 with the liquid crystal compound of the present invention can be improved due to the AC stabilizing effect.

l-93 CS-1014 A ferroelectric liquid crystal element was prepared using this liquid crystal composite in the same manner as in Example 2, except that the liquid crystal layer thickness was 1.5 μm.

Using the above liquid crystal element, the tilt angle was measured under crossed Nicols conditions at 25°C. Next, microscopic observation was performed while applying a square wave of ±8 V at a frequency of 60 KHz, and the tilt angle was measured. Also, the transmittance at this time was measured. moreover,
Contrast ratio was also measured.

The results are shown below.

Orthogonal Nicols Lower Tilt angle application Lower Tilt angle 1/Transmittance Contrast ratio CS-1014 Liquid crystal composition N 7° 7.6° 8.8° 13.6° 7.8% 12.1% 8: 1 39 : 1 From the above, CS-1014 has Δε almost 0.
It was found that the display characteristics of a liquid crystal element obtained by mixing the liquid crystal compound of the present invention with the liquid crystal compound of the present invention can be improved due to the AC stabilizing effect.

Example 14 In place of the 1.5% dimethylacetamide solution of the polyimide resin precursor used in Example 2, a 2% aqueous solution of polyvinyl alcohol resin [Kuraray (Kiyuki Co., Ltd. PUA-117) was used. Create a dielectric liquid crystal element,
The optical response speed was measured in the same manner as in Example 2. The results are shown below.

15°0 25°C 35°C126
μsec 89 1t see 75 μsec
c Example 15 A ferroelectric liquid crystal element was created in the same manner as in Example 2, except that the alignment control layer was created only with polyimide resin without using Sj02 used in Example 2. Optical response speed was measured in a similar manner. The results are shown below.

15℃ 25℃ 35℃122μse
c 86 μsec 72 μsec Example 1
4. As is clear from Example 15, even when the element configuration is changed, the element containing the ferroelectric liquid crystal composition according to the present invention has greatly improved low-temperature operation characteristics and response speed as in Example 2. Temperature dependence is reduced.

〔Effect of the invention〕

A device containing the ferroelectric liquid crystal composite of the present invention can be a liquid crystal device with good switching characteristics, improved low-temperature operation characteristics, and a liquid crystal device with reduced temperature dependence of response speed. .

Furthermore, when used in a display method based on the AC stabilization effect, display characteristics can be significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of an example of a liquid crystal element using ferroelectric liquid crystal. 2 and 3 are perspective views schematically showing an example of an element cell for explaining the operation of a ferroelectric liquid crystal element. Figure 4 shows four types of FL with different physical properties regarding Δε.
It is a figure which shows the change of (theta)a with respect to Vrms of C. In Fig. 1, l...... Ferroelectric liquid crystal layer 2...
・・・・・・・・・・・・Glass substrate 3・・・・・・
・・・・・・・・・Transparent electrode 4・・・・・・・・・・
・・Insulating orientation control layer 5・・・・・・・・・・・・・・
・Subasa・6 ・・・・・・・・・・・・・・・Lead wire 7・・・・・・・・・・・・・・Power supply 8・・・・・・・・・...Polarizing plate 9...
・・・・・・・・・・・・・・・Light source Io・・・・・・
・・・・・・・・・・・・Incoming light [Transmitted light In Figure 2, 21a 2lb Substrate Substrate Ferroelectric liquid crystal layer Liquid crystal molecule dipole moment (P soil) In Figure 3, 31a 3lb 33a 33b 34a 34b ...... Ea Eb Voltage application means Voltage application means 1st stable state 2nd stable state Upward dipole moment Downward dipole moment Upward electric field Downward electric field

Claims (3)

[Claims] (1) The following general formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (However, R_1 and R_2 are linear or branched alkyl groups having 1 to 18 carbon atoms, and the alkyl group One or more non-adjacent methylene groups may be replaced by ▲There are mathematical formulas, chemical formulas, tables, etc.▼ However, Z represents -O- or -S-, and R_3 represents H or carbon. It represents an alkyl group of numbers 1 to 5. Furthermore, at least one of R_1 and R_2 is optically active. Also, A represents -A_1-, -A_1-A_2-, and A_1 and A_2 each represent a ▲mathematical formula, chemical formula, or table. A liquid crystalline compound represented by ▼. (2) A liquid crystal composition containing at least one of the liquid crystal compounds according to claim 1. (3) A liquid crystal element, characterized in that the liquid crystal composition according to claim 2 is disposed between a pair of electrode substrates.