JPH0312477A - Ferroelectric chiral smectic liquid crystal composition and liquid crystal element containing same - Google Patents

Abstract

PURPOSE:To obtain the subject composition, containing two kinds of liquid crystal compounds having specific structures and a liquid crystal compound having a negative dielectric anisotropy and excellent in display and operation characteristics due to switching characteristics and AC stabilizing effects with small temperature dependence of response speed. CONSTITUTION:The objective composition obtained by blending (A) a compound expressed by formula I (R1 is 1-18C chain alkyl capable of containing a substituent group; X1 is single bond, -O-, etc.; Z is single bond or formula II; formula III is formula IV or V) with (B) a compound expressed by formula VI (R2 and R3 are 1-18C chain alkyl which can be substituted with 1-12C alkoxy, provided that both are optically inactive group; X2 and X3 are -O-, formula II, etc.; p and q are 0-2, provided that p and q are not simultaneously 0) and (C) liquid crystal compound having a negative dielectric anisotropy ( epsilon). Furthermore, a compound having epsilon<-10, such as a compound expressed by formula VII, is preferred as the component (C).

Description

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

[Background technology]

Conventionally, liquid crystals have been applied as electro-optical elements in various fields. Most of the liquid crystal elements currently in practical use are, for example, M, 5chadt and W, “Applied Physics Letters” by Helfrich.
Vo, 18, No. 4 (1971, 2, 15), P
, 127-128'Voltage-Spenden
t 0ptical Activity of
aTwisted Nematic Liqui
d TN (twiste) shown in Crysta Pi
It uses a d nematic type liquid crystal.

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

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

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

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

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

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

In particular, it is expected to be applied to high-speed optical shutters and high-density, large-screen displays. 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 characteristics for use in liquid crystal devices, including low-temperature operation characteristics and high-speed response. It is hard to say that it is equipped with the following.

To increase the response speed, (a) increase the magnitude of spontaneous polarization Ps (b) increase the viscosity η
There is a method of reducing the voltage and increasing the applied voltage E.However, since the applied voltage is driven by an IC or the like, there is an upper limit to the applied voltage, and it is desirable that the applied voltage be as low as possible.

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

- In ferroelectric chiral smectic liquid crystal compounds with large spontaneous polarization, the internal electric field of the cell caused by the spontaneous polarization tends to be large (and there are many restrictions on the device configuration that can take a bistable state). Furthermore, even if the spontaneous polarization is increased unnecessarily, the viscosity tends to increase as well, and as a result, the response speed may not be very fast.

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

As mentioned above, in order to put ferroelectric liquid crystal devices into practical use, a ferroelectric chiral smectic liquid crystal composition that has low viscosity, high-speed response, and small temperature dependence of response speed is required. .

A typical ferroelectric liquid crystal cell has an I
Form an electrode pattern using TO, etc., and form a short-circuit prevention layer for the upper and lower substrates using SiO2, etc. (approximately 1000 people).
etc.) A film is formed to a thickness of about 400 layers, and the PI film is rubbed and then faced to each other in a vertically symmetrical orientation, and the spacing between the substrates is maintained at 1 to 3 μm.

On the other hand, it is known that ferroelectric liquid crystals aligned under such conditions generally connect the upper and lower substrates in a twisted state and do not exhibit -axial alignment (spray alignment). One of the problems in such a case is that the transmittance of the liquid crystal layer is low.

Assuming uniaxial molecular orientation, the amount of transmitted light is the incident light I under crossed Nicols. We obtain the intensity of I for the intensity of .

λ Here, Δn is the refractive index anisotropy, d is the cell thickness, λ is the wavelength of the incident light, and θa is the angle between bistable states (tilt angle).

When the above cell is used and spray orientation is adopted, θa is currently 5° to 8°. Since Δndπ/λ cannot be easily controlled in terms of physical properties, it is desirable to increase θa (and thereby increase I), but this is difficult to achieve using static alignment techniques.

To solve this problem, it is known that θa can be expanded by using the torque of the Δε term of the ferroelectric liquid crystal (published by ATT in 1983.3 ID, JP-A-61-245142.61- 246722.61-24
6723.61-246724.61-249024.
6l-249025).

When Δε of the liquid crystal is negative, the liquid crystal molecules tend to become parallel to the substrate due to the application of an electric field. Taking advantage of this property, i.e.
By applying a constant effective electric field even during switching, it is possible to eliminate this twisted arrangement, increase θa, and increase the transmittance (AC stabilization effect).

The torque r acting on the FLC molecule regarding state switching
P1 and the torque rΔ that acts on the FLC molecules regarding the AC stabilizing effect are each proportional to the following physical properties.

1' Ps 0eIPs @E... (2) r
Δa oo・Δε・ε.・E2 ...... (3
) As is clear from equation (3), it can be seen that 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 using a rectangular alternating current of 60 KHz to eliminate the influence of Ps.

(1) is Δε knee 5.5, (II) is Δε~-3,0,
(m) is Δε˜−〇, and (rV) is Δε˜1.0.

As can be seen from the graph, θa becomes large at extremely low voltages where Δε is large in the negative, 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) (60KHz±8V (when applying a square wave).

As is known from the above examples, the display characteristics of SS FLC can be greatly changed by controlling the physical properties of Δε and Ps.

In order to make the Δε of the ferroelectric liquid crystal composition negative,
It is most effective to mix materials with a negative Δε and a large absolute value. For example, a compound with a large Δε can be obtained by introducing a halogen or cyano group in the short axis direction of the molecule, or by introducing a heteroatom into the molecular ring skeleton.

The dielectric anisotropy of a compound with Δε<0 varies depending on its structure. An example is shown below.

2 ≦ ε ≦ 5 5 ε1<10 ε　く2 1ε ＞　　10 vinegar *R, R' represent an alkyl group.

Broadly classified, compounds with 1εi≦2 (1Δε1 small), compounds with 2×1εl≦10 (1Δε1 medium), and Δεl>
It can be divided into three types: 10 (lΔεl large). 1Δ
ε; A small value has almost no effect on increasing 1Δε1. A material with 1Δε greater than 1 is a very effective material for increasing 1Δε. At present, only dicyanohydroquinone derivatives are materials with a 1Δε;

However, dicyanohydroquinone derivatives have jΔ
Although the effect of increasing εI is large, since the viscosity is high, an increase in the content ratio tends to deteriorate the switching characteristics.

On the other hand, among those with medium 1Δε1, the IΔε increasing effect is smaller than that of the large 1Δε1 component, but some have low viscosity to some extent.

From the above, it is clear that the switching characteristics are good and the A
In order to obtain a liquid crystal composition having a C stabilizing effect and a liquid crystal element containing the same, a compound having negative dielectric anisotropy,
Preferably, it is necessary to carefully select the compound of 1Δε1>2, the mixing partner, and the mixing ratio.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a chiral smectic liquid crystal composition having a high response speed (and reduced temperature dependence of the response speed) and a liquid crystal element using such a liquid crystal composition so that a ferroelectric liquid crystal element can be put to practical use. Our goal is to provide the following.

Another object of the present invention is to provide a liquid crystal element which has an AC stabilizing effect and greatly improves display characteristics by further mixing a liquid crystal compound with negative dielectric anisotropy into a liquid crystal composition. be.

[Means for solving the problem] The present invention is based on the following general formula (I) [However, R3 is a linear or branched alkyl group which may have a C1 to C+S substituent, and , indicates a single bond, -O-, or -C○-.

shows. ] At least one compound represented by the following general formula (II) (R2+ R3 may have a linear or branched alkyl group of C1 to Cl11, and an alkoxy group of 01 to CI2 as a substituent. However, it is non-optically active.X2
゜p and q are OSl or 2. However, at the same time p
=Q, q=Q does not hold. ) A ferroelectric chiral smectic liquid crystal composition characterized by containing at least one compound represented by (a) and at least one liquid crystal compound having negative dielectric anisotropy, and the liquid crystal composition. A liquid crystal element arranged between a pair of electrode substrates is provided.

Further, in the present invention, the liquid crystalline compound having negative dielectric anisotropy preferably exhibits Δε<-2, more preferably Δε<-5.
The present invention provides a ferroelectric chiral smectic liquid crystal composition in which the ferroelectric chiral smectic liquid crystal composition further contains a liquid crystal compound exhibiting Δε<-10, and a liquid crystal element having the same. .

Further, the present invention provides the ferroelectric chiral smectic liquid crystal using a compound selected from the following general formulas (■-■) to (■-■) as the liquid crystalline compound having negative dielectric anisotropy. The present invention provides a ferroelectric chiral smectic liquid crystal composition, which further contains a ferroelectric chiral smectic liquid crystal composition, and a liquid crystal element having the same.

General formula (m-■) General formula (■-■) [R6+ Rh is a linear or branched alkyl group that may have a substituent, (R,, R+ has a substituent and A linear or branched alkyl group, As, A, and t cannot be single bonds at the same time.] General formula (■-■) When Aa and Ab are both single bonds, Xb and Xc are single bonds. and Xa and Xd are both a single bond or both are 10-, or Xa is -CO- and xd is 10C-.

II II Y, , Yb is a cyano group, halogen, hydrogen, provided that Ya
, Yb cannot become hydrogen at the same time. ]R+, Rj is a straight chain or branched alkyl group that may have a substituent,
However, when A is a single bond, it is a straight chain alkyl group, and Z,
is -O or S1 General formula (■-■) However, when A is a single bond, X is a single bond, (Ri + Rm is a linear or branched alkyl group that may have a substituent, <, When A+ is a single bond, Xit is a single bond.]Ak
.

A1 cannot be a single bond at the same time.

-CH2CH2- -C=C-] The general formula Ro is a linear or branched alkyl group which may have a substituent. Among the compounds represented by the above general formula, preferred examples of compounds include the following general formula: Examples include compounds represented by the formula %).

(■ a) (I b) \, -22' (R+, II-a)
Examples include compounds represented by ~(II-e').

R2-X2 HFx 3-R3 (II-a) R2-X2-H , -R3 (II-d) Furthermore, the above-mentioned (II-a) ~ (II = e
) Preferred examples of Xz and X3 in the formula include the following (II-i) to (II-viii).

(11-i) Xz is a single bond, x3 is a single bond (If-ii) Xz is a single bond, x3 is a single bond
-〇-(II-iji) X 2 is a single bond,
X3 is -OC-]1 (11-iv) Xz is a single bond, X3 is -
CO-(II-v)

(as mentioned above) (II-vii) X 2 is 10-1x3 is -OC- (II-viii) X 2 is 10-1x3 is -CO-
Furthermore, R in the above formulas (II-a) to (II-e)
2. Preferred examples of R3 are as follows (II-ix)
~(II-xi) can be mentioned.

(II-ix) R2 is an n-alkyl group, R3 is an n-alkyl group Examples of specific structural formulas of the compound represented by the above general formula (I) are shown below.

Un(S is O-7, R4 is a linear or branched alkyl group) (II-xf) R2 is an n-alkyl group.

CH3 R3 is 'c CH2) t CM': CH2) u○
R5 (t is 0 to 7, U is 0 or 11 R5 is a linear or branched alkyl group) (I The compound represented by the general formula is synthesized by synthetic route A or B as shown below.

It can be obtained with C.

Synthetic route A Synthetic route B Synthetic route C CX , : -O-) Representative synthesis examples of the compound represented by the general formula (1) are shown below.

Synthesis Example 1 (Synthesis of Compound No. 2-17) 1.00 g of p-2-fluorooctyloxyphenol (4, 16 m
M) in 10 ml of pyridine. A solution of 1.30 g (6,00 mM) of trans-4-'n-pentylcyclohexanecarboxylic acid chloride dissolved in 5 ml of toluene was heated at 5° C. or below for 20 to 40 ml of toluene.
It was dripped in minutes. After the dropwise addition, the mixture was stirred at room temperature overnight to obtain a white precipitate.

After the reaction was completed, the reaction product was extracted with benzene, and the benzene layer was further washed with distilled water, and then the benzene layer was dried over magnesium sulfate, and the benzene was distilled off. It was further purified using silica gel column chromatography and recrystallized from ethanol/methanol.
n-pentylcyclohexanecarboxylic acid-p-2-fluorooctyloxyphenyl ester 1.20g (2
, 85mM) was obtained. (Yield 68.6%) NMR data (ppm) 0, 83-2, 83 ppm (34H, m
)4.00~4.50ppm (2f-1,q)
7, llppm (4H,5) IR data (cm-') 3456, 2928. 2852. 1742°14
70, 1248. 1200. 1166°854° Phase transition temperature (℃) 1508°1132° (Here, s3.s4.s5.s indicates a phase with a higher degree of order than SmC*.) Synthesis Example 2 (Compound No. 2- Synthesis of 29) In a container sufficiently purged with nitrogen, (-)-2-fluoroheptatool 0
．． 40g (3.0mmol) and dry pyridine 1.00
g (13 mmoJ) and dried under water cooling for 30 minutes.

Add 0.69 g of p-)luenesulfonic acid chloride to the solution.
(3.6 mmof) was added, and stirring was continued for 5 hours. After the reaction was completed, 1NH chloride was added, extraction was performed twice with 10 ml of methylene chloride, and the extract was washed once with 10 ml of distilled water. After appropriately adding anhydrous sodium sulfate to the obtained methylene chloride solution and drying, the solvent was distilled off to obtain +)-2-fluoroheptyl p-toluenesulfonic acid ester 0.59 g (2, Ommo, l)
I got it.

Yield is 66%. The specific rotation and IR data of the product are as follows.

Specific optical rotation [α] +2.59° (C=1, CHCl
3).

Specific optical rotation [α] +9.58° (c = 1, C
HCl3).

iR (cm”) 2 2900, 2850. 1600, 1450.1
350, 1170, 1090, 980.810,
660, 550° 0.43 g (1,5
mmol) and 0.28 g (1.0 mmol) of 5-octyl-2-(4-hydroxyphenyl)pyrimidine
-Butanol 0.2 ml was added and stirred well.

Add 1.0 ml of l-butanol to the solution in advance.
Sodium hydroxide 0.048g (1.2mmol)
An alkaline solution prepared by dissolving was immediately poured into the solution, and the mixture was heated and refluxed for 5 and a half hours. After the reaction is complete, add 10ml of distilled water.
was added and extracted once with 10 ml and 5 ml of benzene, respectively, and the extract was dried by appropriately adding anhydrous sodium sulfate. After drying, the solvent was distilled off and the desired product (
+)-5-octyl-2-[4-(2-fluoroheptyloxy)phenyl]pyrimidine 0,17 g (0
, 43 mmol) was obtained.

The yield was 43%, and the specific rotation and IR were as follows:
The data was obtained.

Specific optical rotation [α] +0.44° (cm 1,, C
1 (C10).

Specific optical rotation [α coy + 4.19° (cm 1,
CHCl3).

IR (cm”): 2900.2850, 1600.1580.1420,
1250.1260.800.720, 650, 55
0° Examples of specific structural formulas of the liquid crystalline compound represented by the general formula (II) are shown below.

vinegar C5H11 (to) CIQH21 General formula (II) The compound represented by For example, East Germany Patent 95892 (1973), Patent Publication Sho 62-5434 It can be obtained by the method described in .

or, for example, The compound represented by Synthesize using the following synthetic route be able to.

(R2+ R3+ pl Q in the formula is as described above) A typical synthesis example of the compound represented by the general formula (II) is shown below.

Synthesis example! , (Synthesis of compound No. 2-60) 1.0 5-methoxyhexanol dissolved in 5 ml of pyridine
1.83 g (9°6 mmol) of p-toluenesulfonic acid chloride dissolved in 5 ml of pyridine was added dropwise to 6 g (8.0 mmol) in an ice-water solution at 5° C. or lower. 6 at room temperature
After stirring for an hour, the reaction mixture was poured into 100 ml of cold water. After making the mixture acidic with 6N hydrochloric acid, the mixture was extracted with isopropyl ether. After washing the organic layer with water, it was dried over anhydrous magnesium sulfate, and then the solvent was distilled off to give 5-methoxyhexyl-
p-Toluenesulfone I. was obtained.

5-decyl-2-(p
-hydroxyphenyl)pyrimidine 2.0g (6゜4
1mmol1), add 0.61g of potassium hydroxide,
Stirred at 0°C for 40 minutes. To this was added the previously obtained 5-methoxyhexyl-p-toluenesulfonate, and 100
The mixture was heated and stirred at ℃ for 4 hours. After the reaction was completed, the reaction mixture was poured into 100 ml of cold water and extracted with benzene. After washing with water, it was dried over anhydrous magnesium sulfate, and the solvent was distilled off to obtain a pale yellow oil. After purification by column chromatography (silica gel - ethyl acetate/benzene = 1/9), it was recrystallized from hexane to give 5-decyl-2-(4-(5
' -methoxyhexyloxy)phenyl)pyridine (
Compound Nα.

2-60) 1.35g was obtained.

Phase Transition Temperature Examples of specific structural formulas of liquid crystal compounds represented by the general formulas (■-■) to (■-■) are shown below. however,(
In formula II [), the number of carbon atoms in the alkyl group represented by each R is 1 to 18, preferably 4 to 16, more preferably 6 to 1.
2 is shown.

General formula (■-■) SuririRisuC m RiRiN Su (N ρN ρN SuN General formula (■-■) r (3, -68) RiRiRisu general formula (■-■) Ririg3-128 ) General formula (■-■) General formula (■-■) N N N N N N N N N N N N N (3-1,75) N N N N The liquid crystal composition of the present invention has the general formula (1) It can be obtained by mixing at least one of the compounds represented by formula (II), at least one of the compounds represented by the general formula (II), and one or more other liquid crystal compounds in an appropriate ratio. .

A liquid crystal composition for another purpose of the present invention can be obtained by further mixing at least one liquid crystal compound having negative dielectric anisotropy in an appropriate ratio to the above liquid crystal composition.

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.

Ca HITO + COS + 0CII 2 ClIC
2H5NeF Soot Invention 9 In the ferroelectric liquid crystal composition of the present invention, a liquid crystalline compound represented by the general formula (RI) of the present invention, a liquid crystalline compound represented by the general formula (I[), respectively, and the other liquid crystals mentioned above. The compounding ratio of at least one type of chemical compound or a liquid crystal composition containing the same (abbreviated as liquid crystal material) is the liquid crystal compound represented by the general formula (1) or general formula (II) of the present invention, per 100 parts by weight of the liquid crystal material. It is preferable that the amount of each of these compounds is 1 to 300 parts by weight, more preferably 2 to 100 parts by weight.

Furthermore, when using two or more of the liquid crystal compounds represented by general formula (1) and general formula (II) of the present invention, the blending ratio with other liquid crystal materials is 100% Parts by weight, general formula (I) of the present invention, general formula (
It is desirable that any or all of the liquid crystalline compounds represented by [[) be used in an amount of 1 to 500 parts by weight, more preferably 2 to 100 parts by weight.

Furthermore, the weight ratio of the liquid crystalline compound represented by general formula (n) to the liquid crystalline compound represented by general formula (I) [general formula (
I)/general formula (■)] is 1/300 to 300/1, preferably 1150 to 50/1.

When using two or more of the liquid crystal compounds represented by general formula (1) and general formula (II), the ratio of general formula (I)/general formula (n) is 11500 to 500/1, preferably 1150 to 50. /1 is desirable.

In addition, the compounding ratio of the liquid crystal compound represented by general formula (I), the total amount of the liquid crystal compound represented by general formula (I[), and the above-mentioned liquid crystal material is the same as that of general formula (I) It is desirable that the amount of other liquid crystal materials be 2 to 600 parts by weight, preferably 4 to 200 parts by weight, per 100 parts by weight of the total amount of n).

Furthermore, when using two or more of each of the liquid crystalline compounds represented by general formula (1) and general formula (n), - general formula (1)
The total amount of the liquid crystal compound represented by the formula (II) and the alignment ratio of the liquid crystal material described above is per 100 parts by weight of the total amount of the general formula (I) and the general formula (n). It is desirable that the above-mentioned liquid crystal material be used in an amount of 2 to 1000 parts by weight, preferably 4 to 200 parts by weight.

Furthermore, the content of the component with negative dielectric anisotropy in the ferroelectric liquid crystal composition containing the component with negative dielectric anisotropy is 1
~98% by weight. In particular, when using a component with Δε<-2, the content of the component with Δε<-2 is desirably 1 to 70% by weight, preferably 1 to 50% by weight.

A liquid crystal compound represented by general formula (1) and general formula (II
) and the component with negative dielectric anisotropy in the ferroelectric liquid crystal composition of the present invention.
Contains ~100% by weight.

The dielectric anisotropy of the liquid crystalline compound having negative dielectric anisotropy used in the present invention is preferably 1ε1>2.

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

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

The two glass substrates 2 are each coated with In 203 +S
nO2 or ITO (Indium-Tin 0x
A transparent electrode made of 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 insulating layer of inorganic material such as zirconium oxide, titanium oxide or magnesium fluoride, and then apply polyvinyl alcohol, polyimide, polyamideimide, polyesterimide, polyvaraxylene, 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 (
Solvent o 4-20% by weight, preferably 0.2-10% by weight
) using a spinner coating method, dip coating method, screen printing method, spray coating method, roll coating method, etc.
It can be cured and formed under predetermined curing conditions (for example, under heating).

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

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

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

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

In addition, this ferroelectric liquid crystal has an SmC* phase (chiral smectic C phase) in a wide temperature range including room temperature (especially on the low temperature side), and when used as an element, it has low viscosity and high-speed response. This is desirable. Furthermore, it is desired that the temperature dependence of the response speed be small.

In addition, in order to exhibit good homogeneous orientation and obtain a monodomain state especially when used as an element, the ferroelectric liquid crystal must be changed from the tomoyoshi phase to the ch phase (cholesteric phase) -8mA phase (smectic A phase) -3mC* Phase (chiral smectic C phase)
It is desirable to have the following phase transition series.

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

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

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

FIG. 2 schematically depicts an example of a cell for explaining the operation of a ferroelectric liquid crystal element. 21a and 21b are In203, SnO2 or ITO (In
It is a substrate (glass plate) coated with a transparent electrode made of a thin film such as dium-Tin oxide), between which a liquid crystal molecular layer 22 is oriented perpendicularly to the glass surface.
Liquid crystal of mC* phase or SmH* phase is sealed. A thick line 23 represents a liquid crystal molecule, and this liquid crystal molecule 23 has a dipole moment (P) 24 in a direction perpendicular to the molecule. When a voltage higher than a certain threshold is applied between the electrodes on the substrates 21a and 21°b, the helical structure of the liquid crystal molecules 23 is unraveled, and the dipole moment (P±)
24 are all oriented in the direction of the electric field (so that the liquid crystal molecules 23 can change the orientation 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, 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 (34a). 34b).In such a cell, as shown in FIG.
is applied by the voltage applying means and 31b, the dipole moment changes direction to upward direction 34a or downward direction 34b corresponding to the electric field angle of the electric field Ea or El), and accordingly, the liquid crystal molecules move to the first stable state. It is oriented to either the state 33a or the second stable state 33b.

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

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

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 1 A liquid crystal composition 1-A was prepared by mixing one part of the following mold.

Illustrative structure formula
Weight part hardware No.

C4Hs OCH2CH20+ COO+ C00Ca
) I l* Exemplified Compounds 1-3 and 2-9 were mixed with the liquid crystal composition 1-A in the following parts by weight to obtain a liquid crystal composition 1-B.

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

Prepare two 1.1 mm thick glass plates, form an ITO film on each glass plate, create a voltage application electrode,
Furthermore, 5i02 was deposited on top of this to form an insulating layer.

On this substrate, a polyimide resin precursor [Toshikuki 5P-5
10] 1.0% dimethylacetamide solution at 3 rotations.
It was applied for 15 seconds using a 00Or, pom spinner. After the film was formed, a heating condensation firing process was performed at 300° C. for 60 minutes.

The thickness of the coating film at this time was about 120 people.

This fired coating was rubbed with acetate flocked cloth, then washed with isopropyl alcohol solution, and silica beads with an average particle size of 1.5 μm were sprinkled on one glass plate. so that they are parallel to each other, and apply adhesive sealant [Rixon Bond (
Glass plates were glued together using Nisso (Japanese) and dried by heating at 100° C. for 60 minutes to create a cell. The cell thickness of this cell was measured using a Bereck phase plate and was approximately 1.
It was 5 μm.

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

Using this ferroelectric liquid crystal element, the optical response under crossed Nicols (transmitted light amount change 0~90%) was detected by applying a voltage of peak-to-peak voltage V pp =25 V, and the response speed ( (hereinafter referred to as optical response speed) was measured.

The results are shown below.

10°C 25°0 40°C Response speed 970 μsec 270 ps
ec 85 μsec Further, the contrast during this driving at 25° C. was 12, and a clear switching operation was observed.

Comparative Example 1 Liquid crystal composition 1 in which only exemplary compound No. 2-9 was mixed with 1-A without mixing exemplary compound No. 1-3 of liquid crystal composition 1-B mixed in Example 1. Liquid crystal composition 1- in which only exemplary compound No. 1-3 was mixed with 1-A without mixing -C and exemplary compound No. 2-9
I created a new version.

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

Response speed 10°0 25°C 40°C1-
A, 1600 μsec 430 ps
ec 120 μsec1-0 1360 μ
sec 370 μsec 105 μsec
c1-D 1080μsec 300μsec
90 μsec As is clear from Example 1 and Comparative Example 1, the ferroelectric liquid crystal element containing the liquid crystal composition 1-B according to the present invention has improved operating characteristics and high-speed response at low temperatures, and Example 2 The temperature dependence of speed is reduced. Liquid crystal composition 1-A mixed in Example 1 is mixed with the exemplified compounds shown below in the shaking section shown below to prepare liquid crystal composition 2-B. I got it.

Exemplary Compound Na Structural Formula A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that this was used, and the optical response speed 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.

Response speed 10℃ 25℃ 40℃ 875 μsec 230 μsec 75 μs
ec Also, the contrast during this drive at 25° C. was 13, a clear switching operation was observed, and the bistability was also good when the voltage application was stopped.

-A Comparative Example 2 Among the liquid crystal compositions 2-B mixed in Example 2, exemplified compounds No. 1-10. Liquid crystal composition 2-C in which only exemplary compound No. 2-60.2-69 was mixed with l-A without mixing 1-13, and exemplary compound No. 2-60. 2
Exemplary compound No. 1-A without mixing -69.

1-10. Liquid crystal composition 2- containing only 1-13 mixed
Created D.

A ferroelectric liquid crystal device was prepared in the same manner as in Example 1, except that liquid crystal compositions 2-C and 2-D were injected into the cell instead of using liquid crystal composition 1-B, and the optical response was The speed was measured and the results are shown below.

Response speed 10℃ 25℃40℃2-CI4
00μsec 380μsec 1lOuse
c2-D 1050 μsec 310 μ
sec 90 μsec As is clear from Example 2 and Comparative Example 2, the ferroelectric liquid crystal element containing the liquid crystal composition 2-B according to the present invention has improved operating characteristics and high-speed response at low temperatures, In addition, the temperature dependence of response speed is reduced.

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

S-A A ferroelectric liquid crystal element was produced in the same manner as in Example 1, except that this element was used, and the optical response speed was measured in the same manner as in Example 1, and the switching state and the like were observed.

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

Comparative Example 3 Of the liquid crystal composition 3-H mixed in Example 3, only Exemplified Compound No. 2-82.2-100 was mixed with l-A without mixing Exemplified Compound No. 1-17. Liquid crystal composition 3-D was prepared by mixing only exemplary compound No. 1-17 with respect to 1-A without mixing liquid crystal composition 3-C and exemplary compound No. 2-82.2-100.

Instead of using liquid crystal composition 1-B, liquid crystal composition 3-C is used.
A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that 3-D and 3-D were injected into the cell, and the optical response speed was measured.

The results are shown below.

10℃ 25℃ 40℃ Response speed 1000 μsec 260 μsec
Further, the contrast during this driving at 25° C. was 12, a clear switching operation was observed, and the bistability was also good when the voltage application was stopped.

Response speed 10℃ 25℃ 40'C3-
CI450 μsec 390 μsec
115 μ5ec3-D l300 μsec
330 μsec 105 μsec As is clear from Example 3 and Comparative Example 3, the ferroelectric liquid crystal element containing the liquid crystal composition 3-B according to the present invention has improved operating characteristics and high-speed response at low temperatures. , and the temperature dependence of the response speed is reduced.

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

S-A A ferroelectric liquid crystal element was produced in the same manner as in Example 1, except that this element was used, and the optical response speed was measured in the same manner as in Example 1, and the switching state and the like were observed.

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

10℃ 25℃ 40℃ Response speed 895 μsec 238 p sec
80 μsec Further, the contrast during this drive at 25° C. was I4, a clear switching operation was observed, and the bistability was also good when the voltage application was stopped.

Comparative Example 4 Among the liquid crystal compositions 4-H mixed in Example 4, Exemplary Compound No. 1-26. Liquid crystal composition 4-C in which only exemplary compound No. 2-23.2-31 was mixed with 1-A without mixing 1-54 and exemplary compound No. 2-23.2-3
Exemplary compound No., 1- for l-A without mixing 1°
A liquid crystal composition 3-D was prepared by mixing only 26°1-54.

A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that liquid crystal compositions 4-C and 4-D were injected into the cell instead of using liquid crystal composition 1-B, and the optical response was The speed was measured. The results are shown below.

Response speed 10℃ 25℃ 40℃4-C
I285 μsec 315 μsec 1
00 μ5ec4-D 1125 μsec
2681 t sec 90 p sec As is clear from Example 4 and Comparative Example 4, the ferroelectric liquid crystal element containing the liquid crystal composition 4-B according to the present invention has improved operating characteristics and high-speed response at low temperatures. and the temperature dependence of response speed is reduced.

Example 5 Liquid crystal composition 1-A mixed in Example 1 was mixed with 1 part of the following exemplified compounds to obtain liquid crystal composition 5-B.

Exemplary Compound NQ Structural Formula A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that this was used, and the optical response speed was measured in the same manner as in Example 1 and the switching state etc. was observed. .

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

10℃ 25℃ 40℃Response speed
965 μsec 250 μsec 85 μs
ec Also, the contrast during this drive at 25° C. was 13, a clear switching operation was observed, and the bistability was also good when the voltage application was stopped.

Comparative Example 5 Of the liquid crystal composition 5-H mixed in Example 5, only exemplary compound No. 2-58.2-66 was mixed with 1-A without mixing exemplary compound No. 1-40. Liquid crystal composition 5
Liquid crystal composition 5-D was prepared by mixing only exemplary compound No. 1-40 with 1-A without mixing -C and exemplary compound No. 2-58.2-66.

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

Response speed 10'c 25°C40°C3-
C1250μsec 350μsec 1
05 μ5ec5-D 1150 μsec
308 μsec 97 μsec As is clear from Example 5 and Comparative Example 5, the liquid crystal composition 5-
A ferroelectric liquid crystal element containing B has improved operating characteristics and high-speed response at low temperatures, and has reduced temperature dependence of response speed.

Example 6 Liquid crystal composition 1-A mixed in Example 1 was mixed with 1 part of the exemplified compounds shown below to obtain liquid crystal composition 6-B.

A ferroelectric liquid crystal element was produced in the same manner as in Example 1 except that this was used, and the optical response speed was measured in the same manner as in Example 1, and the switching state and the like were observed.

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

10℃ 25℃ 40℃ Response speed 985 μsec 2701t see
Furthermore, the contrast during this drive at 30° C. was 12, a clear switching operation was observed, and the bistability was also good when the voltage application was stopped.

Comparative Example 6 Of the liquid crystal composition 6-B mixed in Example 6, Exemplified Compound No. 1-63.1-68 was not mixed, and Exemplified Compound No. 2-83.2-112 was mixed with respect to 1-A. Liquid crystal composition 6-C mixed with Exemplary Compound No. 2-83.2-1
Exemplary compound No. 1-A for 1-A without mixing 12
A liquid crystal composition 6-D was prepared by mixing only 63°1-68.

A ferroelectric liquid crystal device was prepared in the same manner as in Example 1, except that liquid crystal compositions 6-C and 6-D were injected into the cell instead of using liquid crystal composition 1-B, and the optical response was The speed was measured. The results are shown below.

Response speed 10°C 25°0 40°C6-
Cl350 μsec 375 μsec
115μ5ec6-D 1180μsec
3101. tsec loOμsec
As is clear from Example 6 and Comparative Example 6, the ferroelectric liquid crystal element containing the liquid crystal composition 6-B according to the present invention has a higher
The operating characteristics and high-speed response at low temperatures have been improved, and the temperature dependence of the response speed has been reduced.

Example 7 Liquid crystal composition mixed in the following parts by weight? -A was created.

Exemplary compound 1-3.2- for this liquid crystal composition 7-A
9 in the following parts by weight, respectively, to prepare liquid crystal composition 7-B.
I got it.

-A A ferroelectric liquid crystal element was prepared in the same manner as in Example 1 except that the liquid crystal composition was replaced with this liquid crystal composition, and the optical response speed 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.

10℃ 25℃ 40℃ response speed 1
300 μsec 340 μsec 120 μsec
sec Furthermore, the contrast during this driving at 25° C. was 13, and a clear switching operation was observed.

Comparative Example 7 Among the liquid crystal compositions mixed in Example 7, exemplary compound No.
Exemplary compound No. for 7-A without mixing 1-3,
Liquid crystal composition 7-C in which only 2-9 was mixed with Exemplified Compound No. Liquid crystal composition 7-D in which only Exemplified Compound No. 1-3 was mixed with 7-A without 2-9. Created.

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

10℃ 25℃ 40℃ Response speed μsec μsec μ5ec7
-A 2000 530 1587-C1
700460145 7-D 1600 400 135 As is clear from Example 7 and Comparative Example 7, the ferroelectric liquid crystal element containing liquid crystal composition 7-B according to the present invention has improved operating characteristics and high-speed response at low temperatures. and the temperature dependence of response speed is reduced.

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

exemplification
Heavy parts - structure
Formulation A ferroelectric liquid crystal element was produced in the same manner as in Example 1 except that this was used, the optical response speed was measured in the same manner as in Example 1, and the switching state etc. were observed. The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below.

10℃ 25℃ 40℃Response speed
1100μsec 270μsec 97μsec
Also, the contrast during this drive at 25°C is 14
A clear switching behavior was observed, and the bistability was also good when the voltage application was stopped.

Comparative Example 8 Among the liquid crystal compositions 8-B mixed in Example 8, 7-A was prepared without mixing exemplified compounds No. 1-10 and 1-13.
For example compound No. 2-60. Liquid crystal composition 8-C mixed with only 2-69 and exemplified compound No. 2-6
0.

Exemplary compound No. for 7-A without mixing 2-69,
A liquid crystal composition 8-D was prepared by mixing only 1-10.1-13.

A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that liquid crystal compositions 8-C and 8-D were injected into the cell instead of using liquid crystal composition 1-B, and the optical response speed was improved. It was measured.

The results are shown below.

10℃ 25℃ 40℃ Response speed μsec μsec usec7
-C1445380120 7-D 1195 305 100 Example 8
As is clear from Comparative Example 8, the ferroelectric liquid crystal element containing the liquid crystal composition 8-B according to the present invention has improved operating characteristics and high-speed response at low temperatures, and has a lower temperature dependence of response speed. It has been reduced.

Example 9 Liquid crystal composition 7-A mixed in Example 7 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 9-B.

A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that this formula was used, and the optical response speed was measured in the same manner as in Example 1 and the switching state etc. was observed. .

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

10℃ 25℃ 40℃Response speed
1210μsec 300μsec 110μsec
c Also, the contrast during this drive at 25°C is 1
4, clear switching behavior was observed, and good bistability was observed when voltage application was stopped.

Comparative Example 9 Of the liquid crystal composition 9-B mixed in Example 9, only exemplary compound No. 2-58.2-66 was mixed with 7-A without mixing exemplary compound No. 1-40. Liquid crystal composition 9
Liquid crystal composition 1-D was prepared by mixing only exemplary compound No. 1-40 with 7-A without mixing -C and exemplary compound No. 2-58.2-66.

A ferroelectric liquid crystal device was prepared in the same manner as in Example 1, except that liquid crystal compositions 9-C and 9-D were injected into the cell instead of using liquid crystal composition 1-B, and the optical response was The speed was measured and the results are shown below.

Response speed io℃ 25℃40℃9-Cl8
00 μsec 460 μsec 145
μ5ec9-D 1540 g, sec
390 μsec 130 At seeAs is clear from Example 9 and Comparative Example 9, the ferroelectric liquid crystal element containing the liquid crystal composition 9-B according to the present invention has improved operating characteristics and high-speed response at low temperatures. and the temperature dependence of response speed is reduced.

Example 10 A liquid crystal composition 10-A was prepared by mixing the following parts by weight.

exemplification Compound No.

Structural formula Exemplary compound 1-3.2 for this liquid crystal composition 10-8
-9 in the following parts by weight, respectively, to prepare liquid crystal composition 10.
-B was obtained.

0-A A ferroelectric liquid crystal element was prepared in the same manner as in Example 1 except that the liquid crystal composition was replaced with this liquid crystal composition, and the optical response speed was measured in the same manner as in Example 1 to determine the switching state. etc. were observed. The uniform alignment within this liquid crystal element was good and a monodomain state was obtained.3 The measurement results are shown below.

10℃ 25℃ 40℃ response speed
375 p sec 95 μsec 35 p
sec Furthermore, the contrast during this driving at 25° C. was 13, and a clear switching operation was observed.

Comparative Example 10 Among the liquid crystal compositions mixed in the example, exemplary compound No.
Illustrative compound No. 10-A without mixing l-3
, Liquid crystal composition 1o-c in which only Exemplified Compound No. 2-9 was mixed with Exemplified Compound No. 10-C, in which Exemplified Compound No. 1-3 was mixed with Exemplified Compound No. 10-A without mixing Exemplified Compound No. 2-9.
Created D.

Instead of using liquid crystal composition 1-B, liquid crystal composition 10-A is used.
, except for injecting 10-C and 10-D into the cell.
A ferroelectric liquid crystal device was prepared in the same manner as in Example 1, and its optical response speed was measured. The results are shown below.

10℃ 25℃40℃ Response speed μsec μsec usecl
o-A 620 170 5210-C
55015048 10-D 445 120 40 As is clear from Example 1O and Comparative Example 10, the ferroelectric liquid crystal element containing the liquid crystal composition 10-B according to the present invention has better operating characteristics and high-speed response at low temperatures. This has been improved, and the temperature dependence of response speed has been reduced.

Example 11 Liquid crystal composition 11-B was obtained by mixing the following exemplified compounds in the weight parts shown below with respect to liquid crystal composition 10-A mixed in Example 10.

Exemplary Compound Ha Structural Formula A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that this was used, and the optical response speed was measured in the same manner as in Example 1 and the switching state etc. was observed. . The uniform alignment within this liquid crystal element was good, and a monodomain state was obtained.

The measurement results are shown below.

10°C 25°C 40°C Response speed 400 μsec 103 μsec
Further, the contrast during this driving at 25° C. was 12, a clear switching operation was observed, and the bistability was also good when the voltage application was stopped.

Comparative Example 11 Among the liquid crystal compositions 11-B mixed in Example 11, exemplified compounds No. 1-17 were not mixed with 10-A, and exemplified compounds No. 2-28. Liquid crystal composition 11-C mixed with only 2-100 and exemplified compound No. 2-82.2
Exemplary compound N for 10-A without mixing -100
A liquid crystal composition 11-D was prepared by mixing only 1-1.7.

Liquid crystal composition! -B instead of using liquid crystal composition 11-C
and 11-D into the cell, all <Example 1>
A ferroelectric liquid crystal device was created using the same method, and its optical response speed was measured. The results are shown below.

10℃ 25℃ 40℃ Response speed μsec μsec μ5ec1
1-C57015249 11-D 500 135
45 As is clear from Example 11 and Comparative Example 11, the ferroelectric liquid crystal element containing the liquid crystal composition 11-B according to the present invention has improved operating characteristics and high-speed response at low temperatures, and has a higher response speed. temperature dependence is reduced.

Example 12 Liquid crystal composition 10-A mixed in Example 10 was mixed with 1 part of the following exemplified compounds to obtain liquid crystal composition 12-B.

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

10℃ 25℃ 40℃ Response speed 310 μsec 83 μsec
Further, the contrast during this driving at 25° C. was 14, a clear switching operation was observed, and the bistability was also good when the voltage application was stopped.

Comparative Example 12 Among the liquid crystal compositions 12-B mixed in Example 12, Exemplified Compound No. 1-26.1-54 was not mixed, and Exemplified Compound No. 2-23. Liquid crystal composition 12-C mixed with only 2-31 and exemplified compound No. 2-23
Exemplary compound N for 10-A without mixing ゜2-31
o, 1-26. Liquid crystal composition 1 mixed only with 1-54
2-D was created.

Instead of using liquid crystal composition 1-B, liquid crystal composition 12-C is used.
All Example 1 except that 12-D and 12-D were injected into the cell.
A ferroelectric liquid crystal device was created using the same method as described above, and the optical response speed was measured. The results are shown below.

Response speed io℃ 25℃ 40℃12-C
515 p sec 140 μsec 45
μ5ec12-D 445 μsec 12
0 μsec 40 p sec As is clear from Example 12 and Comparative Example 12, the liquid crystal composition 12 according to the present invention
The ferroelectric liquid crystal element containing -B has improved operating characteristics and high-speed response at low temperatures, and has reduced temperature dependence of the response speed.

Example 13 The liquid crystal composition used in Example 1 and the comparative example was
A ferroelectric liquid crystal element was prepared in the same manner as in Example 1, except that the alignment control layer was formed only with polyimide resin, and the optical response speed was measured in the same manner as in Example 1.

The results are shown below.

Response speed 10℃ 25℃ 40℃
I -8875μsec 245μsec 7
6 μsec1-A 1450 μsec 3
90 μsec 105 μsec1-C1230
μsec 330 μsec 96 μsec
1-D 990μsec 275μsec
85 μsec As is clear from Example 13, even when the element configuration is changed, the ferroelectric liquid crystal composition 1-
As in Example 1, the element containing B has greatly improved low-temperature operating characteristics and reduced temperature dependence of response speed, compared to elements containing other liquid crystal compositions.

Examples 14 to 21 In place of the exemplified compounds and liquid crystal compositions used in Example 1.10, each part by weight of the exemplified compounds and liquid crystal compositions shown in Table 1 were used to prepare 14-B to 21-B. A liquid crystal composition was obtained. A ferroelectric liquid crystal element was prepared using the same method as in Example 1, and the optical response speed was measured using the same method as in Example 1, and the switching state was observed. Uniform orientation within the device is good;
A monodomain state was obtained. The measurement results are shown in Table 1.

Example 22 Liquid crystal composition 1-B used in Example 1 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 22-B.

Exemplary compound Nα Structural formula Part by weight A ferroelectric liquid crystal device was prepared in the same manner as in Example 1, except that this liquid crystal composition was used, and the optical response speed was measured in the same manner as in Example 1. .

Optical response speed 10°C 25°0 40°C], 100
μsec 295 μsec 93 μsec Furthermore, using the overnight crystal element described above, the tilt angle was measured under crossed Nicols at 25° C. and found to be 7.8°. Next, the tilt angle was measured while applying a ±8v square wave at a frequency of 60 KHz, and found to be 13.9°. When the transmittance was measured at this time, it was 13.8%. At the same time, the contrast ratio was measured and found to be 50:1.

Comparative Example 22 In place of Liquid Crystal Composition 1-B, Liquid Crystal Composition 22-C was prepared by adding the above-described compound 3-10 to Liquid Crystal Composition 1-A in the same ratio as Example 22.

Using these liquid crystal compositions 22-C, 1-A, and 1-B, ferroelectric liquid crystal elements were prepared in the same manner as in Example 1, and the optical response speed was measured in the same manner as in Example 1. did.

Furthermore, the tilt angle was measured in the same manner as in Example 22. The results are shown below.

Optical response speed 10'0 25℃ 40℃1-A I
600 μsec 430 μsec 120 μsec
5ec1-I3 970 μsec 270 μsec
c 85 μ5ec22-CI 928 μsec
470 μsec 1.331tsec Tilt angle (25℃) Initial tilt angle At AC stabilization (no electric field) (When applying 60KHz, ±8V square wave) 1-A7.5° 7.8°1-87.3
° 7.6°22-C7,7°
13.3° As is clear from Example 22 and Comparative Example 22, by mixing a liquid crystal compound with negative dielectric anisotropy into the liquid crystal composition of the present invention, not only the response characteristics were improved, but also the response characteristics were improved. It has been found that when used in a display method based on the AC stabilization effect, the display characteristics are significantly improved.

Example 23 Liquid crystal composition 1-B used in Example 1 was mixed with the following exemplified compounds in the weight parts shown below to obtain liquid crystal composition 23-B.

Exemplary compound Na Structural formula Heavy 1
Part Exemplary Compound Nα Structural Formula A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that this liquid crystal composition was used, and the optical response speed was measured in the same manner as in Example 1.

Optical response speed 10℃ 25℃40℃ 1045μsec 292μsec 89
Further, when the tilt angle of the above liquid crystal element was measured under crossed Nicols at 25° C., it was 8.7°. Next, the tilt angle was measured while applying a square wave of ±8 V at a frequency of 60 KHz, and found to be 13.5°. When the transmittance was measured at this time, it was 14.3%. At the same time, the contrast ratio was measured: 58:
It was 1.

Comparative Example 23 In place of liquid crystal composition 1-B, the above-mentioned disease 3-90.3-12.3-112.3-70.3-1 was added to liquid crystal composition 1-A.
A liquid crystal composition 23-C was prepared in which the compounds No. 07°3-111 and 3-166 were contained in the same proportions as in Example 23.

Using these liquid crystal compositions 23-C, 1-A, and 1-B, ferroelectric liquid crystal elements were prepared in the same manner as in Example 1, and the optical response speed was measured in the same manner as in Example 1. did.

Furthermore, the tilt angle was measured in exactly the same manner as in Example 23. The results are shown below.

Optical response speed 10°C25°C 40°C 1-A 1600 μsec 430 tLsec
120 μ5ec1-8 970 μsec 27
0μsec 85μ5ec23-Cl767μs
ec 453 μsec 129 μsec Tilt angle (25℃) Initial tilt angle At AC stabilization (no electric field) (When applying 60KHz, ±8V square wave) 1-A 7.5° 7.8°1-
8 7.3° 7.6°23-C8,
3° 13.0° Example 23 and Comparative Example 23
As is clear from the above, by mixing a liquid crystal compound with negative dielectric anisotropy into the liquid crystal composition according to the present invention, not only the response characteristics are improved, but also when used in a display method using AC stabilization effect, It was found that the display characteristics were significantly improved.

As is clear from Examples 14 to 23, the ferroelectric liquid crystal elements containing liquid crystal compositions 14-B to 23-B according to the present invention have improved operating characteristics and high response speed at low temperatures, and have improved response speed. Temperature dependence is reduced.

Further, as is clear from Examples 22 and 23, when the liquid crystal composition according to the present invention is used in a display method based on the AC stabilization effect, the display characteristics are significantly improved.

〔Effect of the invention〕

A device containing the ferroelectric liquid crystal composition of the present invention is a liquid crystal device having good switching characteristics and improved operating characteristics.
In addition, a liquid crystal element with reduced temperature dependence of response speed can be obtained.

Furthermore, by using the ferroelectric liquid crystal composition containing the specific compound of the present invention, it is possible to obtain a liquid crystal element that not only has the above-mentioned characteristics but also has greatly improved display characteristics due to the AC stabilization effect.

[Brief explanation of drawings]

Figure 1 is a schematic cross-sectional view of an example of a liquid crystal display element using ferroelectric liquid crystal, and Figures 2 and 3 are schematic diagrams of an example of an element cell to explain the operation of a ferroelectric liquid crystal element. Figure 4 is a perspective view showing the relationship between θ and Vrms of FLCs with different values of Δε.
It is a figure which shows the change of a. In FIG. 1, l......ferroelectric liquid crystal layer 2.
......Glass substrate 3...
・・・・・・・・・・・・・・・Transparent electrode 4・・・・・・
...... Insulating orientation control layer 5 ......
・・・・・・Spacer 6 ・・・・・・・・・・・・
・・・・・・Lead wire 7・・・・・・・・・・・・・・・
・・・・・・Power supply 8 ・・・・・・・・・・・・・・・
・・・Polarizing plate 9・・・・・・・・・・・・・・・・・・
・ ・Light source 1o・・・・・・・・・・・・・・・Incoming light 1・・・・・・・・・・・・・・・・・・Transmitted light In Fig. 2, 1a Substrate 1b Substrate In FIG. 3, ferroelectric liquid crystal layer 1a
Liquid crystal molecule 1b dipole moment 1-(P soil)
3a Voltage application means 3b
Voltage application means 4a First stable state 4b Second stable state a Upward dipole moment b
downward dipole moment
upward electric field
Downward electric field Z1υ

Claims (5)

[Claims] (1) The following general formula (I) ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) (However, R_1 is a linear or branched alkyl group that may have a substituent of C_1 to C_1_8. and
X_1 indicates a single bond, -O-, ▲a mathematical formula, a chemical formula, a table, etc.▼. Z is a single bond or ▲There is a mathematical formula, chemical formula, table, etc.▼
, and there are ▲mathematical formulas, chemical formulas, tables, etc. ▼ is ▲mathematical formulas,
There are chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼. Further, n represents 1 to 12. ) and the following general formula (II) ▲Mathical formula, chemical formula, table, etc. ▼(II) (R_2 and R_3 are C_1 to C_1_8 linear or branched alkyl groups, as substituents It may have an alkoxy group of C_1 to C_1_2.However, it is non-optically active.X_2 and X_3 are single bonds, -O-, ▲Mathematical formulas, chemical formulas, tables, etc. There are ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, p and q are 0
, 1 or 2. However, at the same time p=0, q=0
It is not. ) A ferroelectric chiral smectic liquid crystal composition comprising at least one compound represented by the following formula and at least one liquid crystal compound having negative dielectric anisotropy (Δε). (2) The liquid crystal compound with negative dielectric anisotropy is Δε<−2
The ferroelectric chiral smectic liquid crystal composition according to claim 1. (3) The liquid crystal compound with negative dielectric anisotropy is Δε<−5
3. The ferroelectric chiral smectic liquid crystal composition according to claim 2. (4) The liquid crystal compound with negative dielectric anisotropy is Δε<−1
4. The ferroelectric chiral smectic liquid crystal composition according to claim 3, wherein the ferroelectric chiral smectic liquid crystal composition is 0. (5) A claim characterized in that the liquid crystalline compound having negative dielectric anisotropy is selected from compounds represented by any one of the following general formulas (III-[1]) to (III-[5]). Item 1
The ferroelectric chiral smectic liquid crystal composition according to item 4. General formula (III-[1]) ▲Mathematical formulas, chemical formulas, tables, etc.▼ [R_a, R_b are linear or branched alkyl groups that may have substituents, X_a, X_d are single bonds, -O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼,
X_b, X_c are single bonds, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, -CH_
2CH_2-, A_a, A_b are single bonds, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (trans), ▲ Mathematical formulas, chemical formulas,
There are tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼
(Trans/Trans), ▲There are mathematical formulas, chemical formulas, tables, etc.▼(Trans), ▲There are mathematical formulas, chemical formulas, tables, etc.▼, If A_a and A_b are both single bonds, X_b and X_c are single bonds, X_
a, X_d are both single bonds or both -O-, or X_a is ▲There is a mathematical formula, chemical formula, table, etc.▼, and X_d
is ▲There are mathematical formulas, chemical formulas, tables, etc.▼. Y_a and Y_b are a cyano group, halogen, and hydrogen; however, Y_a and Y_b cannot be hydrogen at the same time. ] General formula (
III-[2]) ▲Mathematical formulas, chemical formulas, tables, etc.▼ [R_e, R_f are linear or branched alkyl groups that may have substituents, X_e, X_h are single bonds, -O- ,▲There are mathematical formulas, chemical formulas, tables, etc.▼,▲There are mathematical formulas, chemical formulas, tables, etc.▼,
X_f, X_g have ▲mathematical formulas, chemical formulas, tables, etc.▼,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, single bond, A_e,
A_f has ▲mathematical formulas, chemical formulas, tables, etc.▼, ▲mathematical formulas,
There are chemical formulas, tables, etc. ▼, single bond, but A_e, A
__f cannot be a single bond at the same time. ] General formula (III-[
3]) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [A_i is a single bond, ▲There are mathematical formulas, chemical formulas, tables, etc.▼
, A_j is a single bond, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, R_iR_j is a straight chain or branched alkyl group that may have a substituent, however, when A_j is a single bond, it is a straight chain alkyl group, and Z_1 is -O or S , X_i, X_k are single bonds, -O-, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, X_j is a single bond,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
There are tables, etc. ▼, -CH_2O-, -OCH_2-,
However, when A_i is a single bond, X_i is a single bond, and A
When j is ▲There is a mathematical formula, chemical formula, table, etc.▼, ▲There is a mathematical formula, chemical formula, table, etc.▼, X_j is not a single bond,
When A_j is a single bond, X_k is a single bond. ] General formula (III-[4]) ▲ Numerical formulas, chemical formulas, tables, etc. are available▼ [R_l, R_m are linear or branched alkyl groups that may have substituents, A_l, A_m are single bonds, ▲ There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, but A
_k and A_l cannot be a single bond at the same time. X_l is a single bond, -O-, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, X_m is a single bond, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ mathematical formulas,
There are chemical formulas, tables, etc. ▼, -CH_2O, -OCH_
2-, -CH_2CH_2-, -C≡C-] General formula (I
II-[5]) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [R_n, R_o are linear or branched alkyl groups that may have substituents, X_n, X_q are single bonds, -O-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼,
X_o, X_p are single bonds, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, -CH_
2O-, -OCH_2-, -CH_2CH_2-, A_n, A_p are single bonds, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼, A_o is ▲ mathematical formulas, chemical formulas, tables, etc. There are ▼, ▲mathematical formulas, chemical formulas,
There are tables, etc. ▼, Z_2 is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼]