JPH07179856A - Liquid crystalline compound, liquid crystal composition containing the same, liquid crystal element using the liquid crystal composition, display method using the same, and display device - Google Patents

Abstract

PURPOSE:To obtain a compound useful for obtaining a ferroelectric liquid crystal element having a high response speed, a small temperature dependency response speed, and a high contrast by selecting a specified liquid crystal compound. CONSTITUTION:This compound is obtained by selecting a liquid crystal compound represented by the formula: R1-A1-X1-A2-X2-A3-R2 [wherein R1 and R2 are each F, CN, or a 1-20 C alkyl; A1 to A3 each is a single bond, 1,4-phenylene having no or one or two substituents (F, Cl, Br, CH3, CF3 or CN), pyridine-2,5- diyl, pyrimidine-2,5-diyl, piperazine-2,5-diyl, pyridazine-3,6-diyl, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, benzofuran-2,5-diyl, benzofuran-2,6-diyl or the like; at least one of A1 to A3 is benzofuran-2,5-diyl or benzofuran-2,6-diyl; and X1 and X2 are each a single bond, COO, OCO, CH2O, OCH2, CH2CH2, CH=CH or C=C].

Description

Detailed Description of the Invention

[0001]

The present invention relates to a novel liquid crystalline compound,
The present invention relates to a liquid crystal composition containing the same, a liquid crystal element using the same, and a display device, and more specifically, a novel liquid crystal composition having improved response characteristics against an electric field, a liquid crystal display element using the same, a liquid crystal-optical shutter, etc. And a display device using the liquid crystal element for display.

[0002]

2. Description of the Related Art 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. Sch.
adt) and W. Helfri
ch) "Applied Physics Letters (Ap
"Plied Physics Letters)" Vo
l. 18, No. 4 (1971.2.15) P.I. 127
~ 128 "Voltage Dependent O"
optical Activity of a Twis
ted Nematic Liquid Crystal
TN (Twisted Nemati)
A liquid crystal of type c) is used. These are based on the dielectric alignment effect of the liquid crystal, and utilize the effect that the average molecular axis direction is directed in a specific direction by an applied electric field due to the dielectric anisotropy of the liquid crystal molecules. The optical response speed limit of these devices is said to be milliseconds, which is too slow for many applications.

On the other hand, in the application to a large flat display, the driving by the simple matrix system is the most effective in consideration of price, productivity and the like. In the simple matrix system, an electrode configuration in which a scan electrode group and a signal electrode group are configured in a matrix is adopted, and in order to drive them, an address signal is sequentially and selectively selected and applied to the scan electrode group, and the signal electrode group is applied. A time-division driving method is adopted in which a predetermined information signal is synchronized with an address signal and selectively applied in parallel.

However, when the above-mentioned TN type liquid crystal is adopted for the device of such a driving system, the scan electrode is selected and the signal electrode is not selected, or the scan electrode is not selected and the signal electrode is selected. An electric field is applied to a finite amount (so-called "half selection point"). If the difference between the voltage applied to the selection point and the voltage applied to the half-selection point is sufficiently large and the voltage threshold value required to align the liquid crystal molecules perpendicularly to the electric field is set to an intermediate voltage value, the display element is Although it operates normally, when the number of scanning lines (N) is increased, the time (duty ratio) during which an effective electric field is applied to one selection point while scanning the entire screen (one frame) ) Will decrease at a rate of 1 / N. For this reason, the voltage difference as an effective value applied to the selected point and the non-selected point in the case of performing repeated scanning becomes smaller as the number of scanning lines increases, and as a result, lowering of image contrast and crosstalk occur. It is an unavoidable drawback.

Such a phenomenon is caused by a liquid crystal having no bistability (a stable state in which liquid crystal molecules are aligned horizontally with respect to an electrode surface, and a vertical state only while an electric field is effectively applied). This is a problem that is essentially unavoidable when driving (i.e., oriented to) is driven (that is, repeatedly scanned) by utilizing the temporal accumulation effect.

In order to improve this point, the voltage averaging method,
The two-frequency driving method, the multiple matrix method, etc. have already been proposed, but none of them is sufficient, and the increase in the screen size and the density of the display element are stopped because the number of scanning lines cannot be increased sufficiently. This is the current situation.

In order to improve the drawbacks of the conventional liquid crystal device, the use of a liquid crystal device having bistability is explained by Clark and Lagerwall.
1) (Japanese Patent Laid-Open No. 56-107216).
Gazette, U.S. Pat. No. 4,367,924).

Bistable liquid crystals are generally chiral smectic C phase (SmC ^* phase) or H phase (SmH).
Ferroelectric liquid crystal having ^* phase) is used. This ferroelectric liquid crystal has a bistable state consisting of a first optical stable state and a second optical stable state with respect to an electric field. Differently, for example, the liquid crystal is aligned in the first optically stable state for one electric field vector and the second liquid crystal is aligned for the other electric field vector.
The liquid crystal is aligned in the optically stable state. Further, this type of liquid crystal has a property (bistability) of taking one of the two stable states described above in response to an applied electric field and maintaining that state when no electric field is applied.

In addition to the above-mentioned characteristic of having bistability, the ferroelectric liquid crystal has an excellent characteristic of high-speed response. This is because the spontaneous polarization of the ferroelectric liquid crystal and the applied electric field act directly to induce the transition of the alignment state.
It is 3 to 4 orders faster than the response speed due to the effect of the dielectric anisotropy and the electric field.

As described above, the ferroelectric liquid crystal potentially has extremely excellent characteristics, and by utilizing such characteristics, many of the problems of the conventional TN type element described above are solved. A fairly substantial improvement is obtained. In particular, it is expected to be applied to high-speed optical optical shutters and high-density, large-screen displays. For this reason, there has been extensive research on ferroelectric liquid crystal materials, but the ferroelectric liquid crystal materials that have been developed to date are sufficient for use in liquid crystal elements, including low-temperature operability, high-speed response, and contrast. It is hard to say that it has characteristics.

The following equation (1) is used between the response time τ, the magnitude Ps of spontaneous polarization and the viscosity η.

[0012]

[Equation 1] There is a relationship of. Therefore, in order to increase the response speed, there are methods of (a) increasing the magnitude Ps of spontaneous polarization (b) decreasing the viscosity η (c) increasing the applied electric field E. However, the applied electric field has an upper limit because it is driven by an IC or the like, and it is desirable that the applied electric field be as low as possible. Therefore, it is actually necessary to reduce the viscosity η or increase the value of the spontaneous polarization magnitude Ps. Generally, in a ferroelectric chiral smectic liquid crystal compound having a large spontaneous polarization, the internal electric field of the cell caused by the spontaneous polarization is also large, and there is a tendency that there are many restrictions on the device structure that can assume a bistable state. Moreover, even if the spontaneous polarization is unnecessarily increased, the viscosity tends to increase accordingly, and as a result, the response speed may not be so fast.

When the temperature range used as an actual display is, for example, about 5 to 40 ° C., the change in response speed is generally about 20 times, which exceeds the limit of adjustment by the drive voltage and frequency. The current situation.

Further, in general, in the case of a liquid crystal element utilizing the refractive index of liquid crystal, the transmittance under the crossed Nicols has the following (2).
It is represented by a formula.

[0015]

[Equation 2]

In the equation (2), I ₀ is the incident light intensity, I is the transmitted light intensity, θ _a is the apparent tilt angle defined below,
Δn is the refractive index anisotropy, d is the thickness of the liquid crystal layer, and λ is the wavelength of incident light. The apparent tilt angle θ _a in the above-mentioned non-helical structure appears as an angle in the average molecular axis direction of the twisted liquid crystal molecules in the first and second alignment states. According to the equation (2), the maximum transmittance is obtained when the apparent tilt angle θ _a is 22.5 °, and the apparent tilt angle θ in the non-helical structure that realizes the bistability is obtained.
_a must be as close as possible to 22.5 °.

[0017]

However, when it is applied to the ferroelectric liquid crystal of the non-helical structure exhibiting the bistability announced by Clark and Lagawell, it has the following problems. , Which causes a decrease in contrast.

First, an apparent tilt angle θ _{a in a} ferroelectric liquid crystal having a non-helical structure obtained by orienting with a conventional rubbing-treated polyimide film (1 / a of the angle formed by the molecular axes of two stable states). 2) is the tilt angle in the ferroelectric liquid crystal (angle Θ which is 1/2 of the apex angle of the triangular pyramid shown in FIG. 4 described later)
Since it is smaller than, the transmittance is low.

Secondly, even if the contrast is high in a static state where no electric field is applied, when driving display is performed by applying a voltage, liquid crystal molecules fluctuate due to a minute electric field in a non-selection period in matrix driving, and thus black is pale. Become.

As described above, in order to put the ferroelectric liquid crystal device into practical use, a liquid crystal composition having a high-speed response, a small temperature dependence of the response speed, and a high contrast chiral smectic phase. Is required. further,
Uniform display switching, good viewing angle characteristics,
Stable storage at low temperature, spontaneous polarization of liquid crystal composition, reduction of load on driving IC, chiral smectic C pitch, cholesteric pitch, temperature range of liquid crystal phase, optical anisotropy, tilt angle, dielectric anisotropy Etc. need to be optimized.

An object of the present invention is to provide a liquid crystal compound which has a high response speed, is effective in reducing its temperature dependence, and is high in contrast so that a ferroelectric liquid crystal device can be put to practical use. Another object of the present invention is to provide a liquid crystal composition containing the same, particularly a ferroelectric chiral smectic liquid crystal composition, and a liquid crystal element and a display device using the liquid crystal composition.

[0022]

The present invention provides the following general formula (I) R ₁ -A ₁ -X ₁ -A ₂ -X ₂ -A ₃ -R ₂ (I) [wherein R ₁ , R ₂ is F, CN, or has 1 to 2 carbon atoms
0 In some linear, one in branched or cyclic alkyl group (the alkyl group or two or more -CH ₂ - in the condition heteroatoms are not adjacent, -O -, - S -, - CO -,
-CH (CN)-, -CH = CH-, -C≡C- may be substituted, and the hydrogen atom in the alkyl group may be replaced by a fluorine atom). A ₁ , A
₂ , A ₃ are each independently a single bond or unsubstituted or 1,4-phenylene having 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN), pyridine-2,
5-diyl, pyrimidine-2,5-diyl, pyrazine-
2,5-diyl, pyridazine-3,6-diyl, 1,4
-Cyclohexylene, 1,3-dioxane-2,5-diyl, 1,3-dithian-2,5-diyl, thiophene-2,5-diyl, thiazole-2,5-diyl, thiadiazole-2,5- Diyl, benzoxazole-
2,5-diyl, benzoxazole-2,6-diyl, benzothiazole-2,5-diyl, benzothiazole-2,6-diyl, benzofuran-2,5-diyl, benzofuran-2,6-diyl, quinoxaline −
2,6-diyl, quinoline-2,6-diyl, 2,6-
Naphthylene, indane-2,5-diyl, 2-alkylindan-2,5-diyl (alkyl group has 1 carbon atom
To 18 linear or branched alkyl groups), indanone-2,6-diyl, 2-alkylindanone-
2,6-diyl (alkyl group is a linear or branched alkyl group having 1 to 18 carbon atoms), coumarane-
It is selected from 2,5-diyl and 2-alkylcoumarane-2,5-diyl (the alkyl group is a linear or branched alkyl group having 1 to 18 carbon atoms). However, A
_At least one of ₁ , A ₂ and A ₃ is benzofuran-2,5-diyl or benzofuran-2,6-diyl. X ₁ and X ₂ are a single bond, —COO—, —OCO—,
_{-CH 2 O -, - OCH 2} -, - CH 2 CH 2 -, - C
H = CH- and -C≡C-. ] A liquid crystal compound represented by the following formula, a liquid crystal composition containing at least one kind of the liquid crystal compound, a liquid crystal element in which the liquid crystal composition is disposed between a pair of electrode substrates, and a display method and a display device using the same Is provided.

Among the liquid crystalline compounds represented by the above-mentioned general formula, the following compounds (Ia) to (Ic) are mentioned as preferable compounds from the viewpoint of the temperature range of the liquid crystal phase, miscibility, viscosity and orientation.

(Ia) A ₁ is benzofuran-2,5-diyl or benzofuran-2,6-diyl, A ₂ is unsubstituted or has 1 or 2 substituents (F, Cl, Br,
CH ₃ , CF ₃ or CN) having 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-
Diyl, pyrazine-2,5-diyl, pyridazine-3,
6-diyl, 1,4-cyclohexylene, thiophene-
2,5-diyl, thiazole 2,5-diyl, thiadiazole-2,5-diyl, quinoline 2,6-diyl,
A liquid crystal compound selected from 2,6-naphthylene, in which A ₃ and X ₂ are single bonds.

(Ib) A ₁ is benzofuran-2,5-diyl or benzofuran-2,6-diyl, A ₂ ,
A ₃ is an unsubstituted or 1 or 2 substituent (F, Cl,
Br, CH ₃ , CF ₃ or CN), 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,
5-diyl, pyrazine-2,5-diyl, pyridazine-
A liquid crystal compound selected from 3,6-diyl, 1,4-cyclohexylene, thiophene-2,5-diyl, thiazole-2,5-diyl and thiadiazole-2,5-diyl.

(Ic) A ₂ is benzofuran-2,5-diyl or benzofuran-2,6-diyl, A ₁ ,
A ₃ is an unsubstituted or 1 or 2 substituent (F, Cl,
Br, CH ₃ , CF ₃ or CN), 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,
5-diyl, pyrazine-2,5-diyl, pyridazine-
A liquid crystal compound selected from 3,6-diyl, 1,4-cyclohexylene, thiophene-2,5-diyl, thiazole-2,5-diyl and thiadiazole-2,5-diyl.

Further preferred compounds are the following (Iaa)
(Icc) are mentioned.

(Iaa) A ₁ is benzofuran-2,5-
Diyl or benzofuran-2,6-diyl, A ₂
Is an unsubstituted or one or two substituents (F, Cl, B
1,4-phenylene having r, CH ₃ , CF ₃ or CN), and A ₃ and X ₁ and X ₂ are single bonds.

(Iab) A ₁ is benzofuran-2,5-
Diyl or benzofuran 2,6-diyl, A ₂ is pyridine-2,5-diyl, A ₃ and X ₁ , X ₂
Is a liquid crystal compound having a single bond.

(Iac) A ₁ is benzofuran-2,5-
Diyl or benzofuran-2,6diyl, A ₂ is pyrimidine-2,5-diyl, A ₃ and X ₁ , X
₂ is a liquid crystal compound that is a single bond.

(Iad) A ₁ is benzofuran-2,5-
Diyl or benzofuran-2,6-diyl, A ₂
Is 1,4-cyclohexylene, A ₃ and X ₁ , X
₂ is a liquid crystal compound that is a single bond.

(Iba) A ₁ is benzofuran-2,5-
Diyl or benzofuran-2,6-diyl, A ₂
Is an unsubstituted or one or two substituents (F, Cl, B
r, CH ₃ , CF ₃ or CN), and A ₃ is an unsubstituted or 1 or 2 substituent (F, Cl, Br, CH ₃ , CF ₃ or CN). Having 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4-cyclohexylene,
Selected from thiophene-2,5-diyl, thiazole-2,5-diyl, thiadiazole-2,5-diyl, X
Liquid crystal compounds in which ₁ and X ₂ are single bonds.

(Ibb) A ₁ is benzofuran-2,5-
Diyl or benzofuran-2,6-diyl, A ₂
Is pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4-cyclohexylene, thiophene-2,5
-Diyl, thiazole-2,5-diyl, thiadiazole-2,5-diyl, A ₃ is unsubstituted or 1
Or two substituents (F, Cl, Br, CH ₃ , CF ₃
Or CN) with 1,4-phenylene, X ₁ ,
X ₂ is a liquid crystal compound having a single bond.

(Ica) A ₂ is benzofuran-2,5-
Diyl or benzofuran-2,6-diyl, A ₁
Is an unsubstituted or one or two substituents (F, Cl, B
r, CH ₃ , CF ₃ or CN), and A ₃ is an unsubstituted or 1 or 2 substituent (F, Cl, Br, CH ₃ , CF ₃ or CN). Having 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4-cyclohexylene,
Selected from thiophene-2,5-diyl, thiazole-2,5-diyl, thiadiazole-2,5-diyl, X
Liquid crystal compounds in which ₁ and X ₂ are single bonds.

(Icb) A ₂ is benzofuran-2,5-
Diyl or benzofuran-2,6-diyl, A ₁
Is pyridine-2,5-diyl and A ₃ is pyridine-
2,5-diyl, pyrimidine-2,5-diyl, 1,4
-Cyclohexylene, thiophene-2,5-diyl, thiazole-2,5-diyl, thiadiazole-2,5-
A liquid crystal compound selected from diyl, in which X ₁ and X ₂ are single bonds.

(Icc) A ₂ is benzofuran-2,5-
Diyl or benzofuran-2,6-diyl, A ₁
Is pyrimidine-2,5-diyl, A ₃ is pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,
4-cyclohexylene, thiophene-2,5-diyl,
Thiazole-2,5-diyl, thiadiazole-2,5
A liquid crystal compound selected from diyl, wherein X ₁ and X ₂ are single bonds.

When 1,4-phenylene having one or two substituents is present in the liquid crystal compound represented by the general formula (I), preferable substituents are F, Cl, Br and C.
F ₃ and more preferably F.

R ₁ and R ₂ are preferably the following (i) to
Selected from (v).

[0039]

[Chemical 2]

(A is an integer from 1 to 16 and d, g and i are 0
To 7 are integers, b, e, h and j are integers from 1 to 10 and f
Indicates 0 or 1. However, b + d ≦ 16, e + f + g ≦
16, h + i ≦ 16 is satisfied. Y ₁ is a single bond, −
O -, - COO -, - OCO- indicates, Y ₂ is -COO
-, - shows a CH ₂ O-. It may be optically active. ) Next, an example of a method for synthesizing the liquid crystal compound represented by the general formula (I) will be described.

[0041]

[Chemical 3]

[0042] (R ₁ 'is a 2 carbon atoms less radical than _{R 1, R 1, R 2} , A 1, A 2, A 3, X 2 is equivalent to the general formula)

Next, specific structural formulas of the liquid crystal compounds represented by the general formula (I) are shown in Tables 1 to 13. Hereinafter, the abbreviations used in the present invention represent the following groups.

[0044]

[Chemical 4]

[0045]

[Chemical 5]

[0046]

[Table 1]

[0047]

[Table 2]

[0048]

[Table 3]

[0049]

[Table 4]

[0050]

[Table 5]

[0051]

[Table 6]

[0052]

[Table 7]

[0053]

[Table 8]

[0054]

[Table 9]

[0055]

[Table 10]

[0056]

[Table 11]

[0057]

[Table 12]

[0058]

[Table 13]

The liquid crystal composition of the present invention can be obtained by mixing at least one liquid crystal compound represented by the general formula (I) and one or more other liquid crystal compounds in an appropriate ratio. The number of other liquid crystal compounds used in combination is 1 to 5
The range is 0, preferably 1 to 30, and more preferably 3 to 30.

The liquid crystal composition according to the present invention is preferably a ferroelectric liquid crystal composition, particularly a ferroelectric chiral smectic liquid crystal composition.

As other liquid crystal compounds used in the present invention, compounds (III) to (XII) described in JP-A-4-272989, pages 23 to 39, preferred compounds (I
IIa) to (XIId), more preferred compound (III
aa) to (XIIdb). In addition, compounds (III) to (VI), preferable compounds (IIIa) to
(VIf), more preferred compounds (IIIaa) to (V
At least one of R ′ ₁ and R ′ ₂ in Ifa) is compound (VII), (VIII), preferred compounds (VIIa) to (VIIIb), more preferred compound (VIIIba), R ′ ₃ in (VIIIbb),
At least one, and compound of _{R '4 (IX) ~ (} XI
I), preferred compounds (IXa) ~ (XIId), more preferred compounds _{(IXba), R '5,} R' at least one of ₆ in _{(XIIdb) - (CH 2)} E C G F
_The compound which is _{2G + 1} (E: 0-10, G: 1-15 integer) can be used similarly. Furthermore, the following general formula (X
The liquid crystal compounds represented by III) to (XVIII) can also be used.

[0062] _{R '7 -X' 6 - [} Py2] -X '7 - [Ph] -X' 8 ([PhY '7]) N - [Tn] -R' 8 (XIII) R '7 -X _{'6 - [Py2] - [} Ph] -OCO- [Ph4F] (XIV) R' 7 -X '6 - [Py2] - [Ph] -OCO- [Ph34F] (XV) R' 7 - ([PhY _{'7]) Q - [Tz1} ] - [PhY' 8] -X '7 - ([PhY' 9]) R - ([Cy]) T -X '9 -R' 8 (XVI) R '7 - _{[Bo2] -A '4 -X'} 9 -R '8 (XVII) R' 7 - [Bt2] -A '4 -X' 9 -R '8 (XVIII)

[0063] wherein R _'7, R' ₈ represents a linear or branched alkyl group having 1 to 18 hydrogen atoms or carbon atoms, bonded directly and X _'6, X' ₉ in the alkyl group -CH ₂
-One excluding groups, or two or more -CH that are not adjacent
₂ -group is -O-, -CO-, -OCO-, -COO-,
-CH (CH) -, - C (CN) (CH 3) - it may be replaced by.

[0064] Moreover R _'7, R' ₈ is preferably i) to v
iii).

I) an alkyl group having 1 to 15 carbon atoms

[0066]

[Chemical 6]

[0067] N, Q, R, T: 0 or 1 Y _{'7,
Y '8, Y' 9:} H or _{F A '4: Ph, Np} X' 6, X '9: a single bond, -COO -, - OCO -, -
_{O- X '7, X' 8} : single bond, -COO -, - OCO -, -
_{CH 2 O -, - OCH 2} -

Preferred compounds of (XIII) are (XI
IIa).

[0069] _{R '7 -X' 6 - [} Py2] - [Ph] -OCO- [Tn] -R '8 (XIIIa)

Preferred compounds of (XVI) are (XV
Ia) and (XVIb).

[0071] _{R '7 - [Tz1] -} [Ph] -X' 9 -R '8 (XVIa) R' 7 - [PhY '7] - [Tz1] - [PhY' 8] -X '9 -R ' ₈ (XVIb)

Preferred compounds of (XVII) are (X
VIIa) and (XVIIb).

[0073] _{R '7 - [Boa2] -} [Ph] -O-R' 8 (XVIIa) R '7 - [Boa2] - [Np] -O-R' 8 (XVIIb)

Preferred compounds of (XVIII) include (XVIIIa) to (XVIIIc).

[0075] _{R '7 - [Btb2] -} [Ph] -R' 8 (XVIIIa) R '7 - [Btb2] - [Ph] -O-R' 8 (XVIIIb) R '7 - [Btb2] - [Np] -OR ' ₈ (XVIIIc)

Preferred compounds of (XVIa) and (XVIb) include (XVIaa) to (XVIbc). _{R '7 - [Tz1] -} [Ph] -O-R' 8 (XVIaa) R '7 - [Ph] - [Tz1] - [Ph] -R' 8 (XVIba) R '7 - [Ph] - [Tz1 _{] - [Ph] -OR '8} (XVIbb) R' 7 - [Ph] - [Tz1] - [Ph] -OCO-R '8 (XVIbc)

Ph, Py2, Tn, Tz1, Cy, N
Abbreviations for p, Boa2, and Btb2 are in accordance with the above definitions, and other abbreviations are the following groups.

[0078]

[Chemical 7]

When the liquid crystalline compound of the present invention is mixed with one or more of the above liquid crystalline compounds or the liquid crystal composition, the proportion of the liquid crystalline compound of the present invention in the liquid crystal composition obtained by mixing. Is 1% to 80% by weight, preferably 1% to 60% by weight, more preferably 1% to 40% by weight.
Is desirable. When two or more liquid crystal compounds of the present invention are used, the proportion of the mixture of two or more liquid crystal compounds of the present invention in the liquid crystal composition obtained by mixing is 1% by weight to 80% by weight, It is desirable that the amount is preferably 1% by weight to 60% by weight, and more preferably 1% by weight to 40% by weight.

Further, the ferroelectric liquid crystal layer in the ferroelectric liquid crystal device of the present invention is prepared by heating the ferroelectric liquid crystal composition prepared as described above in vacuum to an isotropic liquid temperature,
It is preferable that the liquid crystal layer is sealed in an element cell and gradually cooled to form a liquid crystal layer and then returned to normal pressure.

FIG. 1 is a schematic cross-sectional view showing an example of a liquid crystal element having a ferroelectric liquid crystal layer of the present invention for explaining the structure of the ferroelectric liquid crystal element. In FIG. 1, reference numeral 1 is a ferroelectric liquid crystal layer, 2 is a glass substrate, 3 is a transparent electrode, 4 is an insulating orientation control layer, 5 is a spacer, 6 is a lead wire, 7 is a power source, 8 is a polarizing plate, and 9 is The light source is shown.

The two glass substrates 2 were each coated with In ₂
A transparent electrode 3 made of a thin film of O ₃ , SnO ₂ or ITO (Indium Tin Oxide) is covered. An insulating alignment control layer 4 for arranging liquid crystals in the rubbing direction is formed on top of this by rubbing a polymer thin film such as polyimide with gauze or acetate flocking cloth. Further, as the insulating material, for example, silicon nitride, silicon carbide containing hydrogen, silicon oxide, boron nitride, boron nitride containing hydrogen, cerium oxide, aluminum oxide,
Zirconium oxide, titanium oxide, an inorganic material insulating layer such as magnesium fluoride is formed, and polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, etc. are formed thereon. As an orientation control layer, an organic insulating substance such as polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin or photoresist resin is used.
The insulating orientation control layer 4 may be formed of two layers, or may be an inorganic material insulating orientation control layer or a single organic material insulating orientation control layer. If this insulating orientation control layer is an inorganic type, it can be formed by a vapor deposition method, and if it is an organic type, a solution in which an organic insulating substance is dissolved or a precursor solution thereof (0.1 to 20% by weight in a solvent, preferably 0 2 to 10% by weight)
Can be applied by a spinner coating method, a dip coating method, a screen printing method, a spray coating method, a roll coating method, or the like, and can be cured and formed under predetermined curing conditions (for example, under heating).

The layer thickness of the insulating orientation control layer 4 is usually 10Å to
1 μm, preferably 10 Å to 3000 Å, more preferably 10 Å to 1000 Å are suitable.

The two glass substrates 2 are kept at an arbitrary interval by the spacer 5. For example, there is a method in which silica beads and alumina beads having a predetermined diameter are sandwiched between two glass substrates as spacers, and the periphery is sealed with a sealant, for example, an epoxy adhesive. Alternatively, a polymer film or glass fiber may be used as the spacer. Ferroelectric liquid crystal is enclosed between the two glass substrates.

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

The transparent electrode 3 is connected to an external power source 7 by a lead wire. A polarizing plate 8 is attached to the outside of the glass substrate 2. 1 is a transmissive type, so the light source 9
Is equipped with. FIG. 2 schematically shows an example of a cell for explaining the operation of the ferroelectric liquid crystal element. 21a and 21b are In ₂ O ₃ , SnO ₂ or ITO, respectively.
A substrate (glass plate) covered with a transparent electrode made of a thin film such as (Indium Tin Oxide), between which a liquid crystal of SmC ^* phase or SmH ^* phase in which the liquid crystal molecular layer 22 is oriented perpendicular to the glass surface is formed. It is enclosed.
A thick line 23 represents a liquid crystal molecule, and this liquid crystal molecule 23 has a dipole moment (P⊥) 24 in a direction orthogonal to the molecule. When a voltage above a certain threshold is applied between the electrodes on the substrates 21a and 21b, the helical structure of the liquid crystal molecules 23 is unraveled, and the dipole moment (P⊥)
The liquid crystal molecules 23 can change the orientation direction so that all 24 are oriented in the electric field direction. The liquid crystal molecule 23 has an elongated shape and exhibits refractive index anisotropy in the major axis direction and the minor axis direction thereof. Therefore, for example, if crossed Nicols polarizers are placed above and below the glass surface, the voltage application polarity It is easy to understand that the liquid crystal optical modulator has optical characteristics that change.

The liquid crystal cell preferably used in the optical modulator of the present invention has a sufficiently thin thickness (for example, 1
0 μ or less). As the liquid crystal layer becomes thinner in this way, as shown in FIG. 3, the helical structure of the liquid crystal molecules is unwound even when no electric field is applied, and the dipole moment Pa or Pb thereof is directed upward (34a) or downward (34b). Take either state. When an electric field Ea or Eb having a polarity different from a certain threshold value is applied to such a cell by the voltage applying means 31a and 31b as shown in FIG. 3, the dipole moment is directed upward 34a corresponding to the electric field vector of the electric field Ea or Eb. Alternatively, the liquid crystal molecules are turned downward 34b, and the liquid crystal molecules are aligned in one of the first stable state 33a and the second stable state 33b accordingly.

As described above, there are two advantages of using such a ferroelectric liquid crystal element as an optical modulation element. The first is that the response speed is extremely fast, and the second is that the alignment of the liquid crystal molecules has bistability. Explaining the second point further with reference to FIG. 3, for example, when the electric field Ea is applied, the liquid crystal molecules are aligned in the first stable state 33a, but this state is stable even when the electric field is cut off. Further, when the electric field Eb in the opposite direction is applied, the liquid crystal molecules are brought into the second stable state 33b.
The molecules are oriented to change the direction of the molecules, but they remain in this state even when the electric field is cut off. Further, unless the applied electric field Ea or Eb exceeds a certain threshold value, the previous alignment state is maintained.

FIG. 5 shows an example of the drive waveform used in the present invention. In FIG. 5A, S _S is a selected scanning waveform applied to the selected scanning line, S _N is an unselected scanning waveform not selected, and I _S is a selection information waveform applied to the selected data line. (black), I _N represents the non-selection information signal applied to the data line which is not selected (white). In the figure the _{(I S -S S) (I} N -S S) is the voltage waveforms applied to pixels on a selected scanning line, the voltage (I _S -S _S) is applied pixel black take the display state, the voltage (I _N -
The pixel to which S _S ) is applied has a white display state.

FIG. 5B shows the drive waveform shown in FIG. 5A, which is a time-series waveform when the display shown in FIG. 6 is performed.
In the driving example shown in FIG. 5, the minimum application time Δt of the single polarity voltage applied to the pixels on the selected scanning line corresponds to the time of the writing phase t ₂ , and the time of the 1-line clear t ₁ phase is 2Δt. It is set. The values of the parameters V _S , V ₁ and Δt of the drive waveform shown in FIG. 5 are determined by the switching characteristics of the liquid crystal material used. Here, the bias ratio V ₁ / (V ₁ + V _S ) = 1/3 is fixed. Although it is possible to increase the width of the appropriate drive voltage by increasing the bias ratio, increasing the bias ratio means increasing the amplitude of the information signal, which causes an increase in image quality flicker and contrast. It is not preferable because it causes deterioration. In our study, the bias ratio is 1/3 to 1/4
The degree was practical.

By using the liquid crystal element of the present invention in the display panel section and taking the communication information synchronizing means by the data format as the image information having the scanning line address information and the SYNC signal shown in FIGS. 7 and 8, the liquid crystal display device is obtained. To realize.

In the figure, the symbols are as follows. 101 Ferroelectric Liquid Crystal Display Device 102 Graphic Controller 103 Display Panel 104 Scanning Line Driving Circuit 105 Information Line Driving Circuit 106 Decoder 107 Scanning Signal Generating Circuit 108 Shift Register 109 Line Memory 110 Information Signal Generating Circuit 111 Driving Control Circuit 112 GCPU 113 Host CPU 114 VRAM

The image information is generated by the graphic controller 102 on the main body side and transferred to the display panel 103 according to the signal transfer means shown in FIGS. 7 and 8. The graphic controller 102 includes a CPU (Central Processing Unit, hereinafter abbreviated as GCPU 112) and VRA.
Host CP with M (memory for storing image information) 114 as a core
It controls the image information and communication between the U113 and the liquid crystal display device 101, and the control method of the present invention is mainly realized on the graphic controller 102. A light source is arranged on the back surface of the display panel.

[0094]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1 Preparation of 6- (5-decylpyrimidin-2-yl) -2-octylbenzofuran (Exemplified Compound No. 126)

(1) Production of 4-bromosalicylic acid 300 g (1.96 mol) of 4-aminosalicylic acid, 900 ml of hydrobromic acid (47%) and 900 ml of water were cooled to 0 ° C. 140g of sodium nitrite (2.03
(mol) and 900 ml of water were added dropwise, and the mixture was stirred for 30 minutes. The solution of the obtained diazo compound was cooled in a freezing medium, and 338 g (2.36 mol) of cuprous bromide and hydrobromic acid (4
7%) 900 ml of the mixed solution was added dropwise. After stirring at room temperature for 1 hour, the mixture was extracted with ethyl acetate, washed with water, dried and the solvent was distilled off to obtain 345 g of crude 4-bromosalicylic acid.

(2) Production of methyl 4-bromosalicylate 345 g of 4-bromosalicylic acid, 7 liters of methanol and 400 ml of concentrated sulfuric acid were heated under reflux for 13 hours. After completion of the reaction, the mixture was cooled, 20 liters of water was added, extracted with ethyl acetate, washed with water and dried. After distilling off the solvent, the residue was purified by silica gel column chromatography (developing solvent: hexane) and recrystallization (hexane) to obtain 291 g of methyl 4-bromosalicylate (total yield from 4-aminosalicylic acid 64%). .

(3) Preparation of 2-hydroxy-4-bromobenzyl alcohol 48.3 g (1.27 mo) of lithium aluminum hydride
l) and 800 ml of dry tetrahydrofuran (THF) were cooled, and 291 g of methyl 4-bromosalicylate was added thereto.
A dry THF solution of (1.26 mol) was added dropwise at 0 to 5 ° C. After stirring for 30 minutes at room temperature, the mixture was poured into 3 liters of ice water, and concentrated hydrochloric acid was added until pH 3 was reached. After extraction with ethyl acetate, washing with water and drying, the solvent was distilled off. Purification by silica gel column chromatography (developing solvent: hexane / ethyl acetate = 4/1) and recrystallization (hexane / ethyl acetate once, chloroform once) gave 130 g of 2-hydroxy-4-bromobenzyl alcohol. (Yield 51%).

(4) Preparation of 2-hydroxy-4-bromobenzyltriphenylphosphonium bromide 2-hydroxy-4-bromobenzyl alcohol 127
g (626 mmol) and triphenylphosphine hydrobromide 215 g (626 mmol), acetonitrile 640 m
was refluxed for 4 hours. After completion of the reaction, the mixture was cooled and the precipitated crystals were filtered to obtain 308 g of 2-hydroxy-4-bromobenzyltriphenylphosphonium bromide (yield 94%).

(5) Preparation of 6-bromo-2-octylbenzofuran 2-hydroxy-4-bromobenzyltriphenylphosphonium bromide 11.8 g (22.3 mmol) and nonanoic anhydride 7.34 g (24.6 mmol) ), Toluene 80 ml, triethylamine 9.32 ml (66.
8 mmol) was added and the mixture was refluxed for 6 hours. After the reaction was completed, the precipitated crystals were removed by filtration, and the filtrate was concentrated and purified by silica gel column chromatography (developing solvent: hexane / toluene = 3/2) to give 6-bromo-2-octylbenzofuran 5.89 g. Was obtained (yield 86%).

(6) Preparation of 2-octylbenzofuran-6-boronic acid 6-Bromo-2-octylbenzofuran 5.7 g (1
8.4 mmol) and 50 ml of dry THF are cooled to -70 ° C. and 13 m of n-butyllithium (1.65M) are added thereto.
1 was added dropwise. After stirring at the same temperature for 4 hours, a mixed solution of 9.2 ml of triisopropoxyborone and 15 ml of dry THF was added dropwise, and the mixture was stirred at room temperature for 2 hours. 10 after completion of reaction
27% of hydrochloric acid was added, and the mixture was extracted with ethyl acetate. After the extract was dried, the solvent was distilled off and the residue was purified by recrystallization (hexane) to give 2-octylbenzofuran-6-boronic acid 3.21.
g was obtained (yield 64%).

(7) 6- (5-decylpyrimidine-2-
Preparation of 2-octylbenzofuran 2-octylbenzofuran-6-boronic acid 1.00 g
(3.65 mmol) and 2-chloro-5-decylpyrimidine 0.92 g (3.61 mmol), tetrakis (triphenylphosphine) palladium 0.17 g, 2M-
Aqueous sodium carbonate solution 5.6 ml, toluene 5.6 m
1 and 3 ml of ethanol were heated at 80 ° C. for 5 hours under nitrogen. After completion of the reaction, extraction was performed with toluene, and the extract was dried over anhydrous sodium sulfate. After distilling off the solvent, silica gel chromatography (developing solvent: toluene / ethyl acetate = 10)
0/1) and recrystallized (toluene / methanol) to give 6- (5-decylpyrimidin-2-yl) -2-
1.19 g of octylbenzofuran was obtained (yield 74
%).

Phase transition temperature (° C.)

[0104]

[Chemical 8]

[Example 2] 6- (5-decyloxypyrimidin-2-yl) -2-
Production of Octylbenzofuran (Exemplified Compound No. 128)

2-octylbenzofuran-6-boronic acid (1.00 g, 3.65 mmol) and 2-chloro-5-decyloxypyrimidine (0.98 g, 3.62 mmo).
l), tetrakis (triphenylphosphine) palladium 0.17 g, 2M sodium carbonate aqueous solution 5.6 m
1, toluene 5.6 ml, ethanol 3 ml under nitrogen,
Heated at 80 ° C. for 5 hours. After completion of the reaction, extraction was performed with toluene, and the extract was dried over anhydrous sodium sulfate. After distilling off the solvent, silica gel column chromatography (developing solvent:
It was purified by toluene / ethyl acetate = 100/1) and recrystallization (toluene / methanol) to obtain 0.88 g of 6- (5-decyloxypyrimidin-2-yl) -2-octylbenzofuran (yield 52% ).

Phase transition temperature (° C.)

[0108]

[Chemical 9]

Example 3 5- (5-hexylpyrimidin-2-yl) -2- (4
-Hexylphenyl) benzofuran (Exemplified Compound No.
Production of 72)

(1) Preparation of 2-hydroxy-5-bromobenzyltriphenylphosphonium bromide 2-hydroxy-5-bromobenzyl alcohol 14
5.8 g (718 mmol), triphenylphosphine hydrobromide 246.5 g (718 mmol) and 730 ml of acetonitrile were refluxed for 3 hours. After the reaction is complete, cool down,
The precipitated crystals were filtered to obtain 362 g of 2-hydroxy-5-bromobenzyltriphenylphosphonium bromide (yield 96%).

(2) Preparation of 5-bromo-2- (4-hexylphenyl) benzofuran 69.5 g (338 mmol) of 4-hexylbenzoic acid and 280 ml of thionyl chloride were stirred at 60 ° C. for 2 hours. After completion of the reaction, excess thionyl chloride was distilled off to obtain 4-hexylbenzoic acid chloride. Besides, 2-hydroxy-5
-Bromobenzyltriphenylphosphonium bromide 162 g (307 mmol), toluene 2 liters, triethylamine 128 ml (921 mmol) were added,
Refluxed for 6 hours. After completion of the reaction, the precipitated crystals were removed by filtration, the filtrate was concentrated, and purified by silica gel column chromatography (developing solvent: hexane) to give 5-bromo-2- (4-hexylphenyl) benzofuran 90.
4 g was obtained (yield 83%).

Similarly, 4-octylbenzoic acid chloride was used in place of 4-hexylbenzoic acid chloride used here to prepare 5-bromo-2- (4-hexylphenyl) benzofuran (yield 64%). .

(3) Preparation of 2- (4-hexylphenyl) benzofuran-5-boronic acid 5-bromo-2- (4-hexylphenyl) benzofuran 40.0 g (112 mmol) and dry THF 500 m
1 was cooled to -70 ° C, and 71.3 ml of n-butyllithium (1.65M) was added dropwise thereto. After stirring at the same temperature for 2 hours, 24.4 g of trimethoxyboron (235
mmol) and 155 ml of dry THF are added dropwise,
The mixture was stirred at room temperature for 16 hours. After the reaction, 10% hydrochloric acid 90
ml was added, and the precipitated crystals were filtered. Purification by recrystallization (hexane) yielded 22.0 g of 2- (4-hexylphenyl) benzofuran-5-boronic acid (yield 61
%).

Similarly used here, 5-bromo-2-
Instead of (4-hexylphenyl) benzofuran, 5-
2- (4-octylphenyl) benzofuran-5-using bromo-2- (4-octylphenyl) benzofuran
Boronic acid (64% yield) was produced.

(4) 5- (5-hexylpyrimidine-2
-Yl) -2- (4-hexylphenyl) benzofuran 2.0 g (6.2 mmol) of 2- (4-hexylphenyl) benzofuran-5-boronic acid and 1.23 g of 2-chloro-5-hexylpyrimidine ( 6.2 mmol), tetrakis (triphenylphosphine) palladium 0.23
g, 2M-aqueous sodium carbonate solution 9 ml, benzene 9 m
1 and 5 ml of ethanol were heated at 80 ° C. for 3 hours under nitrogen. After completion of the reaction, extraction was performed with toluene, and the extract was dried over anhydrous sodium sulfate. After the solvent was distilled off, the residue was purified by silica gel column chromatography (developing solvent: toluene) and recrystallization (toluene / methanol) to give 5- (5-hexylpyrimidin-2-yl) -2- (4-hexylphenyl) benzofuran 0. .40 g was obtained (yield 15
%).

Phase transition temperature (° C.)

[0117]

[Chemical 10]

[Example 4] 5- (5-decylpyrimidin-2-yl) -2- (4-
Hexylphenyl) benzofuran (Exemplified Compound No. 7
1) production

2.0 g (6.2 mmol) of 2- (4-hexylphenyl) benzofuran-5-boronic acid and 1.58 g (6.2 mmo) of 2-chloro-5-decylpyrimidine.
l), tetrakis (triphenylphosphine) palladium 0.23 g, 2M-sodium carbonate aqueous solution 9 ml, benzene 9 ml, and ethanol 5 ml under nitrogen at 80 ° C.
Heated for hours. After completion of the reaction, extraction was performed with toluene, and the extract was dried over anhydrous sodium sulfate. After distilling off the solvent, silica gel column chromatography (developing solvent: toluene)
And purified by recrystallization (toluene / methanol) to 5
0.68 g of-(5-decylpyrimidin-2-yl) -2- (4-hexylphenyl) benzofuran was obtained (yield 22%).

Phase transition temperature (° C.)

[0121]

[Chemical 11]

Example 5 Production of 5-octyl-2- (4-hexylphenyl) benzofuran (Exemplified Compound No. 2)

Under nitrogen, 0.56 g of 1-octene (5.0
mmol) and TFH (2.5 ml) were cooled to −14 ° C., and 9-borabicyclo (3,3,1] nonane (0.5 M in THF) (12 ml) was added dropwise thereto. 0 ° C
After reacting for 2 hours at 10 ° C. for 2 hours, 0.10 g of tetrakis (triphenylphosphine) palladium and 5
-Bromo-2- (4-hexylphenyl) benzofuran 1.18 g (3.3 mmol), TFH 9 ml, 3M-
Add 5.2 ml of sodium hydroxide aqueous solution, and add 3 at 60 ° C.
Heated for hours. After completion of the reaction, extraction was performed with toluene, and the extract was dried over anhydrous sodium sulfate. After distilling off the solvent, silica gel column chromatography (developing solvent: toluene)
And purified by recrystallization (toluene / methanol) to 5
0.34 g of -octyl-2- (4-hexylphenyl) benzofuran was obtained (yield 26%).

Phase transition temperature (° C.)

[0125]

[Chemical 12]

Example 6 Production of 5- (5-decylpyrimidin-2-yl) -2-octylbenzofuran (Exemplified Compound No. 111)

(1) Preparation of 5-bromo-2-octylbenzofuran 2-hydroxy-5-bromobenzyltriphenylphosphonium bromide 50.0 g (94.7 mmol) and nonanoic acid anhydride 31.1 g (104 mmol), Toluene 450 ml, triethylamine 39.6 g (392 m
(mol) and refluxed for 6 hours. After completion of the reaction, the precipitated crystals were removed by filtration, the filtrate was concentrated, and purified by silica gel column chromatography (developing solvent: hexane) to give 5-bromo-2-octylbenzofuran 25.
1 g (86% yield).

(2) Preparation of 2-octylbenzofuran-5-boronic acid 5-bromo-2-octylbenzofuran 19.0 g (6
1.5 mmol) and tetrahydrofuran (THF) 19
0 ml was cooled to −70 ° C., and 48 ml of n-butyllithium (1.65M) was added dropwise thereto. After stirring at the same temperature for 4 hours, 17.8 g (171 mm) of trimethoxyboron
ol) and 70 ml of TFH added dropwise at room temperature
Stir for hours. After the reaction was completed, 100 ml of 10% hydrochloric acid was added, and the mixture was extracted with ether. After the extract was dried, the solvent was distilled off and the residue was purified by silica gel column chromatography (developing solvent: hexane / ethyl acetate = 4/1) to obtain 10.9 g of 2-octylbenzofuran-5-boronic acid (yield). 64%).

(3) 5- (5-hexylpyrimidine-2
-Yl) -2-Octylbenzofuran Preparation 2-octylbenzofuran-5-boronic acid 1.7 g
(6.2 mmol) and 2-chloro-5-decylpyrimidine 1.58 g (6.2 mmol), tetrakis (triphenylphosphine) palladium 0.23 g, 2M-aqueous sodium carbonate solution 9 ml, toluene 9 ml, ethanol 5 ml under nitrogen. Heated at 80 ° C. for 3 hours. After completion of the reaction, extraction was performed with toluene, and the extract was dried over anhydrous sodium sulfate. After distilling off the solvent, silica gel column chromatography (developing solvent: toluene) and recrystallization (toluene /
0.92 g of 5- (5-decylpyrimidin-2-yl) -2-octylbenzofuran after purification by methanol)
Was obtained (yield 33%, melting point 60.1 ° C.).

Example 7 Preparation of 5- [4- (1H, 1H-perfluorooctyloxy) phenyl] -2-octylbenzofuran (Exemplified Compound No. 106)

0.30 g (1.08 mmol) of 2-octylbenzofuran-5-boronic acid and 0.60 g of 1H, 1H-perfluorooctyloxy) phenyl bromide.
(1.08 mmol), tetrakis (triphenylphosphine) palladium 0.05 g, 2M aqueous sodium carbonate solution 3 ml, toluene 3 ml, and ethanol 2 ml were heated at 80 ° C. for 3 hours under nitrogen. After completion of the reaction, extraction was performed with toluene, and the extract was dried over anhydrous sodium sulfate. After distilling off the solvent, silica gel column chromatography (developing solvent: toluene) and recrystallization (toluene / methanol)
Was purified by to obtain 0.33 g of 5- [4- (1H, 1H-perfluorooctyloxy) phenyl] -2-octylbenzofuran (yield 43%).

Phase transition temperature (° C.)

[0133]

[Chemical 13]

Example 8 The following compounds were mixed in the following parts by weight to prepare a liquid crystal composition A.

Structural formula parts by weight CH ₉ H ₁₉ -Py2-Ph-OC ₉ H ₁₉ 6 C ₁₀ H ₂₁ -Py2-Ph-OC ₈ H ₁₇ 6 C ₈ H ₁₇ O-Pr1-Ph-O (CH ₂ ) ₅ ^* CH (CH ₃ ) C ₂ H ₅ 7 C ₁₁ H ₂₃ O-Py2-Ph-O (CH ₂ ) ₂ ^* CH (CH ₃ ) C ₂ H ₅ 14 C ₁₀ H ₂₁ -Pr2-Ph-C ₆ H ₁₃ 8 C ₆ H ₁₃ -Py2-Ph-Ph-C ₄ H ₉ 4 C ₈ H ₁₇ -Ph-Pr2-Ph-OC ₅ H ₁₁ 2 C ₃ H ₇ -Cy-COO-Ph-Py1-C ₁₂ H ₂₅ 10 C ₅ H ₁₁ -Cy-COO-Ph-Py1-C ₁₂ H ₂₅ 5 C ₁₀ H ₂₁ O-Ph-COS-Ph-OC ₈ H ₁₇ 10 C ₆ H ₁₃ -Ph-COO-Ph-Ph -OCH ₂ CH (CH ₃ ) C ₂ H ₅ 7 C ₃ H ₇ -Cy-CH ₂ O-Ph-Py1-C ₈ H ₁₇ 7 C ₁₀ H ₂₁ -Ph-Ph-OCH ₂ -Ph-C ₇ H ₁₅ 5 C ₁₂ H ₂₅ -Py2-Ph-OCH ₂ ^* CH (F) C ₅ H ₁₁ 2 C ₅ H ₁₁ -Cy-COO-Ph-OCH ₂ ^* CH (F) C ₆ H ₁₃ 2 C ₁₂ H ₂₅ O-Ph-Pa-COO (CH ₂ ) ₃ ^* CH (CH ₃ ) C ₂ H ₅ 2 C ₁₂ H ₂₅ O-Ph-Pa-O (CH ₂ ) ₃ ^* CH (CH ₃ ) OC ₃ H ₇ 3

Further, with respect to this liquid crystal composition A, the following exemplified compounds were mixed in the respective parts by weight shown below to prepare a liquid crystal composition B.

Exemplified Compound No. Structural formula Weight part 6 C ₇ H ₁₅ -Ha2-Cy-COOC ₆ H ₁₃ 3 16 C ₆ H ₁₃ -Ha2-Ph-Py1-C ₈ H ₁₇ 3 76 C ₃ H ₇ -Py2-Ha2-Tz1-C ₆ H ₁₃₃ A 91

[Embodiment 9] Two 0.7 mm thick glass plates were prepared, an ITO film was formed on each glass plate, a voltage application electrode was prepared, and SiO ₂ was vapor-deposited on the electrode. It was an insulating layer. A 0.2% isopropyl alcohol solution of a silane coupling agent [KBM-602 manufactured by Shin-Etsu Chemical Co., Ltd.] was applied on a glass plate for 15 seconds by a spinner at a rotation speed of 2000 rpm to perform surface treatment. After this, 1
A heat drying treatment was performed at 20 ° C. for 20 minutes. Further, a polyimide resin precursor [SP-510 manufactured by Toray Industries, Inc.] 1.5% dimethylacetamide solution was applied on a glass plate having an ITO film subjected to surface treatment for 15 seconds by a spinner at a rotation speed of 2000. After the film formation, the film was heat-condensed and baked at 300 ° C. for 60 minutes. The film thickness of the coating film at this time is about 250Å
Met.

The coating film after the baking was rubbed with an acetate flocked cloth, washed with an isopropyl alcohol solution, and silica beads having an average particle size of 2 μm were sprinkled on one of the glass plates. Were parallel to each other, and glass plates were stuck together using an adhesive sealant [Rixon bond manufactured by Chisso Corporation], and dried by heating at 100 ° C. for 60 minutes to prepare a cell. The liquid crystal composition B mixed in Example 8 was injected into this cell in an isotropic liquid state and gradually cooled from the isotropic phase to 25 ° C. at 20 ° C./h to prepare a ferroelectric liquid crystal element.
When the cell thickness of this cell was measured with a Berek phase plate, it was about 2 μm. By using this ferroelectric liquid crystal device, an optical response (transmission light amount change 0 under a crossed Nicols state) was obtained by applying a voltage of peak-to-peak voltage V _pp = 20V.
˜90%) was detected and the response speed (hereinafter referred to as optical response speed) was measured. The results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 588 μsec 312 μsec 172 μsec

[Comparative Example 1] A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition A mixed in Example 8 was injected into the cell, and the optical response speed was measured. . The results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 668 μsec 340 μsec 182 μsec

Example 10 A liquid crystal composition C was prepared by mixing the following exemplary compounds in the following parts by weight in place of the exemplary compounds mixed in Example 8.

Exemplified Compound No. Structural formula Weight part 47 C ₈ H ₁₇ -Hb2-Gp2-C ₁₂ H ₂₅ 3 67 C ₈ H ₁₇ -Hb2-Tn-Ph-C ₅ H ₁₁ 3 82 C ₃ H ₇ -Ph-Ha2-Td-C ₁₀ H ₂₁ 2 A 92

A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition C was injected into the cell.
The optical response speed was measured and the switching state was observed.
The uniform alignment in 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 581 μsec 309 μsec 169 μsec

Example 11 A liquid crystal composition D was prepared by mixing the exemplary compounds shown below instead of the exemplary compounds mixed in Example 8 in the following parts by weight.

Exemplified Compound No. Structural formula Weight part 13 C ₁₂ H ₂₅ -Ha2-Cm2-C ₈ H ₁₇ 4 34 C ₆ H ₁₃ -Ha2-Pr2-Ph-OC ₁₀ H ₂₁ 3 56 C ₆ H ₁₃ -Hb2-Ph-Tz1-C ₃ H ₇ 3 A 90

A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition D was injected into the cell.
The optical response speed was measured and the switching state was observed.
The uniform alignment in 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 570 μsec 302 μsec 165 μsec

Example 12 The following compounds were mixed in the following parts by weight to prepare a liquid crystal composition E.

Structural part by weight C ₇ H ₁₅ -Py2-Ph-OC ₉ H ₁₉ 12 C ₁₁ H ₂₃ -Py2-Ph-OC ₆ H ₁₃ 10 C ₈ H ₁₇ -Pr2-Ph-O (CH ₂ ) ₅ ^* CH (CH ₃ ) C ₂ H ₅ 10 C ₁₀ H ₂₁ -Py2-Ph-O (CH ₂ ) ₄ CH (CH ₃ ) OCH ₃ 3 C ₈ H ₁₇ -Py2-Ph-Ph-OC ₆ H ₁₃ 8 C ₆ H ₁₃ O-Ph-OCO-Np-OC ₉ H ₁₉ 4 C ₃ H ₇ -Cy-COO-Ph-Py1-C ₁₁ H ₂₃ 6 C ₈ H ₁₇ -Cy-COO-Ph-Py1-C ₁₁ H ₂₃ 2 C ₅ H ₁₁ -Cy-COO-Ph-Py1-C ₁₁ H ₂₃ 8 C ₁₀ H ₂₁ O-Ph-COO-Ph-OCH ₂ ^* CH (CH ₃ ) C ₂ H ₅ 15 C ₄ H ₉ -Cy-CH ₂ O-Ph-Py1-C ₆ H ₁₃ 7 C ₅ H ₁₁ -Cy-CH ₂ O-Ph-Py1-C ₆ H ₁₃ 7 C ₉ H ₁₉ O-Ph-OCH ₂ -Ph-Ph -C ₇ H ₁₅ 4 C ₆ H ₁₃ ^* CH (CH ₃ ) O-Ph-COO-Ph-Ph-OCO ^* CH (CH ₃ ) OC ₄ H ₉ 2 C ₁₂ H ₂₅ -Py2-Ph-OCO ^* CH (Cl) ^* CH (CH ₃ ) C ₂ H ₅ 2

Further, the liquid crystal composition E was prepared by mixing the following exemplary compounds with the liquid crystal composition E in the weight parts shown below.

Exemplified Compound No. Structural formula Weight part 48 C ₅ H ₁₁ -Hb2-Boa2-C ₆ H ₁₃ 3 120 C ₁₁ H ₂₃ O-Ha1-Np-COOC ₁₀ H ₂₁ 3 136 C ₅ H ₁₁ O-Hb1-Ep1-OC ₉ H ₁₉ 3 E 91

A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition F was injected into the cell.
The optical response speed was measured and the switching state was observed.
The uniform alignment in 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 681 μsec 341 μsec 184 μsec

[Comparative Example 2] A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition E mixed in Example 12 was injected into the cell, and the optical response speed was measured. . The measurement results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 784 μsec 373 μsec 197 μsec

Example 13 A liquid crystal composition G was prepared by mixing the following exemplary compounds in the following parts by weight in place of the exemplary compound mixed in Example 12.

Exemplified Compound No. Structural formula Weight part 11 C ₁₀ H ₂₁ -Ha2-Tz1-C ₄ H ₉ 3 100 C ₃ H ₇ -Ph-CH ₂ O-Hb ₂ -Ph-SC ₇ H ₁₅ 3 107 C ₆ H ₁₃ -Ha1-C ≡ C-Ph-OC ₈ H ₁₇ 3 E 91

A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition G was injected into the cell.
The optical response speed was measured and the switching state was observed.
The uniform alignment in 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 711 μsec 357 μsec 193 μsec [Example 14] Instead of the exemplary compounds mixed in Example 12, the exemplary compounds shown below were mixed in the respective parts by weight shown below to prepare a liquid crystal composition H. It was created.

Exemplified Compound No. Structural formula Weight part 12 C ₁₁ H ₂₃ -Ha2-Bta2-c ₆ H ₁₃ 3 61 C ₉ H ₁₉ -Hb2-Ph-Ph23F-C ₅ H ₁₁ 3 117 C ₄ H ₉ -Ha1-Tn-Ph-OCH ₂ CH (CH ₃ ) OC ₄ H ₉ 3 E 91

A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition H was injected into the cell.
The optical response speed was measured and the switching state was observed.
The uniform alignment in 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 691 μsec 344 μsec 184 μsec

Example 15 The following compounds were mixed in the following parts by weight to prepare a liquid crystal composition I.

Structural part by weight C ₈ H ₁₇ -Py2-Ph-OC ₆ H ₁₃ 10 C ₈ H ₁₇ -Py2-Ph-OC ₉ H ₁₉ 5 C ₁₀ H ₂₁ -Py2-Ph-OCOC ₈ H ₁₇ 7 C ₁₀ H ₂₁ -Py2-Ph-O (CH ₂ ) ₃ CH (CH ₃ ) OC ₃ H ₇ 7 C ₁₂ H ₂₅ -Py2-Ph-O (CH ₂ ) ₄ CH (CH ₃ ) OCH ₃ 6 C ₅ H ₁₁ -Py2-Ph-Ph-C ₆ H ₁₃ 5 C ₇ H ₁₅ -Py2-Ph-Ph-C ₆ H ₁₃ 5 C ₄ H ₉ -Cy-COO-Ph-Py1-C ₁₂ H ₂₅ 8 C ₃ H ₇ -Cy-COO-Ph-Py1-C ₁₀ H ₂₁ 8 C ₉ H ₁₉ O-Ph-COO-Ph-OC ₅ H ₁₁ 20 C ₈ H ₁₇ -Ph-COO-Ph-Ph-OCH ₂ CH (CH ₃ ) C ₂ H ₅ 5 C ₈ H ₁₇ -Ph-OCO-Ph-Ph- ^* CH (CH ₃ ) OCOC ₆ H ₁₃ 5 C ₆ H ₁₃ -Ph-OCH ₂ -Ph-Ph-C ₇ H ₁₅ 6 C ₁₂ H ₂₅ -Py2-Ph-OCH ₂ ^* CH (F) C ₆ H ₁₃ 3

Further, with respect to this liquid crystal composition I, the following exemplary compounds were mixed in the respective parts by weight shown below to prepare a liquid crystal composition J.

Exemplified Compound No. Structural formula Weight part 4 C ₉ H ₁₉ O-Ha2-COO-Ph-C ₁₀ H ₂₁ 4 31 C ₉ H ₁₉ O-Ha2-Ph-OCH ₂ -Ph-C ₅ H ₁₁ 3 46 C ₁₁ H ₂₃ -Hb2 -Np-OCH ₂ C ₆ F ₁₃ 2 I 91 A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition J was injected into the cell, the optical response speed was measured, and switching was performed. The condition was observed. The uniform alignment in 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 511 μsec 262 μsec 134 μsec

Comparative Example 3 A ferroelectric liquid crystal device was prepared in the same manner as in Example 1 except that the liquid crystal composition I mixed in Example 15 was injected into the cell, and the optical response speed was measured. The results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 653 μsec 317 μsec 159 μsec

Example 16 A liquid crystal composition K was prepared by mixing the exemplified compounds shown below instead of the exemplified compound mixed in Example 15 in the respective parts by weight shown below.

Exemplified Compound No. Structural formula Weight part 3 C ₅ H ₁₁ -Ha2-Ph-OCH ₂ ^* CHFC ₆ H ₁₃ 3 10 C ₈ H ₁₇ -Ha2-Id2-C ₈ H ₁₇ 3 134 C ₅ H ₁₁ -Hb1-Pd-C ₇ H ₁₅ 3 I 91

A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition K was injected into the cell.
The optical response speed was measured and the switching state was observed.
The uniform alignment in 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 431 μsec 210 μsec 107 μsec

Example 17 A liquid crystal composition L was prepared by mixing the exemplified compounds shown below instead of the exemplified compound mixed in Example 15 in the following parts by weight.

Exemplified Compound No. Structural formula Weight part 24 C ₃ H ₇ -Ha2-Ph-Id2-C ₆ H ₁₃ 3 69 C ₆ H ₁₃ -Hb2-Dx2-Ph-CN 3 89 C ₁₁ H ₂₃ -Py2-Hb2-Ph3F-C ₆ H ₁₃ 3 I 91

A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the liquid crystal composition L was injected into the cell.
The optical response speed was measured and the switching state was observed.
The uniform alignment in 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 551 μsec 284 μsec 145 μsec

As is clear from Examples 8 to 17, the ferroelectric liquid crystal devices containing the liquid crystal compositions B, C, D, F, G, J, J, K and L according to the present invention have operating characteristics at low temperatures. The high-speed response is improved, and the temperature dependence of the optical response speed is also reduced.

Example 18 Instead of the polyimide resin precursor 1.5% dimethylacetamide solution used in Example 9, a polyvinyl alcohol resin [P manufactured by Kuraray Co., Ltd. was used.
UA-117] A liquid crystal element made of ferroelectric was prepared by the same method except that a 2% aqueous solution was used, and the optical response speed was measured by the same method as in Example 9. The results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 583 μsec 310 μsec 169 μsec

Example 19 SiO used in Example 9
_A ferroelectric liquid crystal device was prepared in the same manner as in Example 9 except that the alignment control layer was prepared using only a polyimide resin without using ₂ , and the optical response speed was measured in the same manner as in Example 9. . The results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 573 μsec 307 μsec 167 μsec

As is clear from Examples 18 and 19, the liquid crystal element containing the ferroelectric liquid crystal composition according to the present invention has much improved low temperature operating characteristics as in Example 9 even when the element structure is changed. Moreover, the temperature dependence of the optical response speed is reduced.

Example 20 The following compounds were mixed in the following parts by weight to prepare a liquid crystal composition M.

Structural part by weight C ₆ H ₁₃ -Py2-Ph-O (CH ₂ ) ₄ C ₃ F ₇ 5 C ₁₁ H ₂₃ -Py2-Ph-OCH ₂ C ₄ F ₉ 10 C ₈ H ₁₇ O-Pr1 -Ph-O (CH ₂ ) ₅ CH (CH ₃ ) C ₂ H ₅ 5 C ₁₀ H ₂₁ -Py2-Ph-O (CH ₂ ) ₄ CH (CH ₃ ) OCH ₃ 10 C ₆ H ₁₃ -Py2-Ph -Ph-C ₈ H ₁₇ 7 C ₈ H ₁₇ -Py2-ph-OC ₆ H ₁₃ 15 C ₅ H ₁₁ -Cy-COO-Ph-Py1-C ₁₂ H ₂₅ 5 C ₄ H ₉ -Cy-COO-Ph -Py1-C ₁₁ H ₂₃ 5 C ₃ H ₇ -Cy-COO-Ph-Py1-C ₁₁ H ₂₃ 5 C ₁₂ H ₂₅ O-Ph-Pa-CO (CH ₂ ) ₃ ^* CH (CH ₃ ) C ₂ H ₅ 2 C ₁₀ H ₂₁ -Py2-Ph-OCH ₂ ^* CH (F) C ₂ H ₅ 5 C ₆ H ₁₃ -Cy-COO-Ph-OCH ₂ ^* CH (F) C ₆ H ₁₃ 2 C ₈ H ₁₇ -Ph-OCO-Ph-Ph-CH (CH ₃ ) OCOC ₆ H ₁₃ 6 C ₈ H ₁₇ -Py2-Ph-OCO-Ph-F 2 C ₇ H ₁₅ O-Ph-Tz1-Ph-C ₅ H ₁₁ 3 C ₆ H ₁₃ O-Btb2-Ph-OCO (CH ₂ ) ₆ C ₂ F ₅ 3 C ₈ H ₁₇ O-Ph-COS-Ph-OCH ₂ C ₃ F ₇ 10

Furthermore, the liquid crystal composition N was prepared by mixing the following exemplary compounds with the liquid crystal composition M in the weight parts shown below.

Exemplified Compound No. Structural formula Weight part 18 C ₅ H ₁₁ -Ha2-CH ₂ O-Ph-Pr1-OCOCH ₂ ^* CH (CF ₃ ) C ₄ H ₉ 3 94 C ₈ H ₁₇ -Ph-Hb2-Ph-C ≡ CC ₁₀ H ₂₁ 3 139 C ₉ H ₁₉ -Hb1-Dt2-Ph-C ₆ H ₁₃ 3 M 91

Next, the optical response was observed using a cell prepared from these liquid crystal compositions by the following procedure.

Prepare two 0.7 mm thick glass plates,
An ITO film was formed on each glass plate to form a voltage application electrode, and SiO ₂ was further vapor-deposited on this to form an insulating layer. A 0.2% isopropyl alcohol solution of a silane coupling agent [KBM-602 manufactured by Shin-Etsu Chemical Co., Ltd.] was applied on a glass plate for 15 seconds by a spinner at a rotation speed of 2000 rpm to perform surface treatment. After this, at 20 ℃ 20
A heat-drying treatment was performed for a minute. Further surface treatment I
A polyimide resin precursor [SP-510 manufactured by Toray Industries, Inc.] 1.0% dimethylacetamide solution was applied on a glass plate with a TO film for 15 seconds by a spinner at a rotation speed of 3000 rpm. After the film formation, the film was heat-condensed and baked at 300 ° C. for 60 minutes. The film thickness of the coating film at this time was about 120Å.

The baked coating was rubbed with an acetate flocked cloth, washed with an isopropyl alcohol solution, and sprayed with silica beads having an average particle size of 1.5 μm on one glass plate, and then each rubbed. The treatment axes were made parallel to each other, and glass plates were bonded together using an adhesive sealant [Rixon bond manufactured by Chisso Corporation], and dried by heating at 100 ° C. for 60 minutes to prepare a cell. When the cell thickness of this cell was measured with a Berek phase plate, it was about 1.5 μm. A liquid crystal composition M was injected into this cell in an isotropic liquid state and gradually cooled from the isotropic phase to 25 ° C. at 20 ° C./h to prepare a ferroelectric liquid crystal element. Using this ferroelectric liquid crystal device, the contrast at the time of driving at 30 ° C. was measured with the driving waveform (1/3 bias ratio) shown in FIG.

[Comparative Example 4] A ferroelectric liquid crystal device was prepared in the same manner as in Example 20 except that the liquid crystal composition M mixed in Example 20 was injected into the cell, and the same drive waveform was used. The contrast during driving at 30 ° C. was measured. As a result, the contrast was 8.1.

Example 21 A liquid crystal composition O was prepared by mixing the following exemplary compounds in the following parts by weight in place of the exemplary compound used in Example 20.

Exemplified Compound No. Structural formula Weight part 25 C ₅ H ₁₁ -Ha2-Ph-Io2-C ₈ H ₁₇ 3 54 C ₉ H ₁₉ -Hb2-Ph-Pa-C ₅ H ₁₁ 3 112 C ₆ H ₁₃ -Ha1-Py1-OC ₆ H ₁₃₃ M 91

A ferroelectric liquid crystal device was prepared in the same manner as in Example 20 except that this liquid crystal composition was used, and the contrast at the time of driving at 30 ° C. was measured using the same driving waveform as in Example 20. did. As a result, the contrast is 1
It was 9.3.

Example 22 A liquid crystal composition P was prepared by mixing the following exemplary compounds in the following parts by weight in place of the exemplary compound used in Example 20.

Exemplified Compound No. Structural formula Weight part 19 C ₉ H ₁₉ -Ha2-Ph-Pa-OCH ₂ CH (CH ₃ ) C ₂ H ₅ 2 92 C ₆ H ₁₃ -Py2-Hb2-Ph-C ₆ H ₁₃ 3 127 C ₁₀ H ₂₁ O-Hb1-Py1-C ₇ H ₁₅ 3 M 92

A ferroelectric liquid crystal device was prepared in the same manner as in Example 20 except that this liquid crystal composition was used, and the contrast at the time of driving at 30 ° C. was measured using the same driving waveform as in Example 20. did. As a result, the contrast is 2
It was 1.0.

Example 23 A liquid crystal composition Q was prepared by mixing the following exemplary compounds in the following parts by weight in place of the exemplary compound used in Example 20.

Exemplified Compound No. Structural formula Weight part 1 C ₆ H ₁₃ -Ha2-Ph-OC ₈ H ₁₇ 3 73 C ₆ H ₁₃ O-Py2-Ha2-Ph2F-C ₅ H ₁₁ 3 129 C ₅ H ₁₁ -Hb1-Py1-CH ₂ CH ₂ -Ph-C ₈ H ₁₇ 2 M 92

A ferroelectric liquid crystal element was prepared in the same manner as in Example 20 except that this liquid crystal composition was used, and the contrast at the time of driving at 30 ° C. was measured using the same driving waveform as in Example 20. did. As a result, the contrast is 1
It was 9.8.

As is clear from Examples 20 to 23, the ferroelectric liquid crystal device containing the liquid crystal compositions N, O, P and Q according to the present invention has a high contrast during driving.

[Example 24] A 2% aqueous solution of polyvinyl alcohol resin [PVA-117 manufactured by Kuraray Co., Ltd.] was used in place of the 1.0% dimethylacetamide solution of the polyimide resin precursor used in Example 20. Example 2
A ferroelectric liquid crystal device was prepared in the same manner as in Example 2, and
As a result of measuring the contrast at the time of driving at 30 ° C. by the same method as 0, the contrast was 20.2.

[Example 25] Si used in Example 20
A ferroelectric liquid crystal element was prepared in the same manner as in Example 20 except that the alignment control layer was formed only with a polyimide resin without using O _2, and when driven at 30 ° C. in the same manner as in Example 20. As a result of measuring the contrast, the contrast was 15.1.

[Example 26] Instead of the polyimide resin precursor 1.0% dimethylacetamide solution used in Example 20, a polyamic acid [LQ180 manufactured by Hitachi Chemical Co., Ltd.] was used.
2] A ferroelectric liquid crystal device was prepared in the same manner as in Example 20 except that 1% NMP solution was used and baked at 270 ° C. for 1 hour. The contrast was measured. As a result, the contrast was 26.3.

As is clear from Examples 24, 25 and 26, even when the element structure was changed, the liquid crystal element containing the ferroelectric liquid crystal composition according to the present invention showed high contrast as in Example 20. There is. Further, as a result of detailed examination even when the drive waveform was changed, it was found that a liquid crystal element containing the ferroelectric liquid crystal composition of the present invention similarly provided higher contrast.

[0209]

The liquid crystal composition containing the liquid crystalline compound of the present invention can be operated by utilizing the ferroelectricity of the liquid crystal composition. The ferroelectric liquid crystal element of the present invention that can be used in this manner is a liquid crystal element having excellent switching characteristics, high-speed response, reduction in temperature dependence of optical response speed, and high contrast. be able to. A display device in which the liquid crystal device of the present invention is used as a display device in combination with a light source, a drive circuit, etc. is a good device.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an example of a liquid crystal element using a liquid crystal exhibiting a chiral smectic phase.

FIG. 2 is a perspective view schematically showing an example of an element cell for explaining the operation of a liquid crystal element utilizing the ferroelectricity of liquid crystal.

FIG. 3 is a perspective view schematically showing an example of an element cell for explaining the operation of a liquid crystal element utilizing the ferroelectricity of liquid crystal.

FIG. 4 is an explanatory diagram showing a tilt angle.

FIG. 5 is a waveform diagram of a driving method of a liquid crystal element used in the present invention.

6 is a schematic diagram of a display pattern when actual driving is performed with the time-series driving waveform shown in FIG.

FIG. 7 is a block configuration diagram showing a liquid crystal display device having a liquid crystal element utilizing ferroelectricity and a graphics controller.

FIG. 8 is a timing chart of image information communication between the liquid crystal display device and the graphic controller.

[Explanation of symbols]

 1 Liquid Crystal Layer Having Chiral Smectic Phase 2 Glass Substrate 3 Transparent Electrode 4 Insulating Alignment Control Layer 5 Spacer 6 Lead Wire 7 Power Supply 8 Deflection Plate 9 Light Sources 21a, 21b Substrate 22 Liquid Crystal Layer 23 Liquid Crystal Molecule 24 Dipole Moment 31a, 31b Voltage Applying means 33a, 33b Stable states 34a, 34b Dipole moment 101 Ferroelectric liquid crystal display device 102 Graphic controller 103 Display panel 104 Scan line driving circuit 105 Information line driving circuit 106 Decoder 107 Scan signal generating circuit 108 Shift register 109 Line memory 110 Information signal generation circuit 111 Drive control circuit 112 GCPU 113 Host CPU 114 VRAM

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI technical indication location G02F 1/13 500 1/141 (72) Inventor Goji Kadono 3-30 Shimomaruko, Ota-ku, Tokyo No. 2 Canon Inc. (72) Inventor Yoko Yamada 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (17)

[Claims] 1. A liquid crystalline compound represented by the following general formula (I): _{R 1 -A 1 -X 1 -A 2} -X 2 -A 3 -R 2 (I) [ wherein, R _1, R ₂ is F, CN, from 1 carbon atoms 2
0 In some linear, one in branched or cyclic alkyl group (the alkyl group or two or more -CH ₂ - in the condition heteroatoms are not adjacent, -O -, - S -, - CO -,
-CH (CN)-, -CH = CH-, -C≡C- may be substituted, and the hydrogen atom in the alkyl group may be replaced by a fluorine atom). A ₁ , A
₂ , A ₃ are each independently a single bond or unsubstituted or 1,4-phenylene having 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN), pyridine-2,
5-diyl, pyrimidine-2,5-diyl, pyrazine-
2,5-diyl, pyridazine-3,6-diyl, 1,4
-Cyclohexylene, 1,3-dioxane-2,5-diyl, 1,3-dithian-2,5-diyl, thiophene-2,5-diyl, thiazole-2,5-diyl, thiadiazole-2,5- Diyl, benzoxazole-
2,5-diyl, benzoxazole-2,6-diyl, benzothiazole-2,5-diyl, benzothiazole-2,6-diyl, benzofuran-2,5-diyl, benzofuran-2,6-diyl, quinoxaline −
2,6-diyl, quinoline-2,6-diyl, 2,6-
Naphthylene, indane-2,5-diyl, 2-alkylindan-2,5-diyl (alkyl group has 1 carbon atom
To 18 linear or branched alkyl groups), indanone-2,6-diyl, 2-alkylindanone-
2,6-diyl (alkyl group is a linear or branched alkyl group having 1 to 18 carbon atoms), coumarane-
2,5-diyl, 2-alkylcoumarane-2,5-diyl (the alkyl group is a linear or branched alkyl group having 1 to 18 carbon atoms). However, A ₁ ,
At least one of A ₂ and A ₃ is benzofuran-
It is 2,5-diyl or benzofuran-2,6-diyl. X ₁ and X ₂ are a single bond, —COO—, —OCO—, —
_{CH 2 O -, - OCH 2} -, - CH 2 CH 2 -, - CH
= CH- and -C≡C-. ] 2. The liquid crystal compound according to claim 1, wherein the liquid crystal compound represented by the general formula is any one of the following (Ia) to (Ic). (Ia) A ₁ is benzofuran-2,5-diyl or benzofuran-2,6-diyl, A ₂ is unsubstituted or has one or two substituents (F, Cl, Br, CH ₃ , CF ₃₎ .
₃ or CN) 1,4-phenylene, pyridine-
2,5-diyl, pyrimidine-2,5-diyl, pyrazine-2,5-diyl, pyridazine-3,6-diyl,
1,4-cyclohexylene, thiophene-2,5-diyl, thiazole 2,5-diyl, thiadiazole-2,
A liquid crystal compound selected from 5-diyl, quinoline 2,6-diyl and 2,6-naphthylene, wherein A ₃ and X ₂ are single bonds (Ib) A ₁ is benzofuran-2,5-diyl or benzofuran-2 , 6-diyl, A ₂ , A ₃ are unsubstituted or have 1 or 2 substituents (F, Cl, Br, CH
_3, CF ₃ or CN) to a 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, pyrazine-2,5-diyl, pyridazine-3,6
Diyl, 1,4-cyclohexylene, thiophene-2,
A liquid crystal compound (Ic) A ₂ selected from 5-diyl, thiazole-2,5-diyl and thiadiazole-2,5-diyl is benzofuran-2,5-diyl or benzofuran-2,6-diyl, and A ₁ , A ₃ are unsubstituted or one or two substituents (F, Cl, Br, CH
_3, CF ₃ or CN) to a 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, pyrazine-2,5-diyl, pyridazine-3,6
Diyl, 1,4-cyclohexylene, thiophene-2,
Liquid crystalline compound selected from 5-diyl, thiazole-2,5-diyl and thiadiazole-2,5-diyl 3. The liquid crystal compound according to claim 1, wherein the liquid crystal compound represented by the general formula (I) is any one of (Iaa) to (Icc). (Iaa) A ₁ is benzofuran-2,5-diyl or benzofuran-2,6-diyl, A ₂ is unsubstituted or has one or two substituents (F, Cl, Br, CH ₃ , C
1,3-phenylene having F ₃ or CN), A
₃ and X ₁ and X ₂ are single bonds, the liquid crystal compound (Iab) A ₁ is benzofuran-2,5-diyl or benzofuran 2,6-diyl, and A ₂ is pyridine-
A liquid crystal compound (Iac) A ₁ is 2,5-diyl and A ₃ and X ₁ and X ₂ are single bonds, and benzofuran-2,5-diyl or benzofuran-2,6diyl is used, and A ₂ is Pyrimidine-
A liquid crystal compound (Iad) A ₁ which is 2,5-diyl and A ₃ and X ₁ and X ₂ are single bonds is benzofuran-2,5-diyl or benzofuran-2,6-diyl, and A ₂ Is 1,4-cyclohexylene, A ₃ and X ₁ , and X ₂ are single bonds, and the liquid crystal compound (Iba) A ₁ is benzofuran-2,5-diyl or benzofuran-2,6-diyl, A ₂ is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH ₃ , C
1,3-phenylene having F ₃ or CN), A
₃ is unsubstituted or 1 or 2 substituents (F, Cl, B
r, CH ₃ , CF ₃ or CN), 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5
-Diyl, 1,4-cyclohexylene, thiophene-
Liquid crystal compound (Ibb) A ₁ selected from 2,5-diyl, thiazole-2,5-diyl and thiadiazole-2,5-diyl, wherein X ₁ and X ₂ are single bonds is benzofuran-2,5- Diyl or benzofuran-2,6-diyl, A ₂ is pyridine-
2,5-diyl, pyrimidine-2,5-diyl, 1,4
-Cyclohexylene, thiophene-2,5-diyl, thiazole-2,5-diyl, thiadiazole-2,5-
Selected from diyl, A ₃ is 1,4-phenylene which is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN), and X ₁ and X ₂ are The liquid crystal compound (Ica) A ₂ which is a single bond is benzofuran-2,5-diyl or benzofuran-2,6-diyl, and A ₁ is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH ₃ , C
1,3-phenylene having F ₃ or CN), A
₃ is unsubstituted or 1 or 2 substituents (F, Cl, B
r, CH ₃ , CF ₃ or CN), 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5
-Diyl, 1,4-cyclohexylene, thiophene-
A liquid crystal compound (Icb) A ₂ selected from 2,5-diyl, thiazole-2,5-diyl and thiadiazole-2,5-diyl, wherein X ₁ and X ₂ are single bonds is benzofuran-2,5- Diyl or benzofuran-2,6-diyl, A ₁ is pyridine-
2,5-diyl, A ₃ is pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4-cyclohexylene, thiophene-2,5-diyl, thiazole-
Liquid crystal compound (Icc) A ₂ selected from 2,5-diyl and thiadiazole-2,5-diyl, wherein X ₁ and X ₂ are single bonds is benzofuran-2,5-diyl or benzofuran-2,6- Diyl, A ₁ is pyrimidine-2,5-diyl, A ₃ is pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4-cyclohexylene, thiophene-2,5-diyl , Thiazole-
Liquid crystalline compound selected from 2,5-diyl and thiadiazole-2,5-diyl, wherein X ₁ and X ₂ are single bonds 4. The liquid crystal compound represented by the general formula (I), wherein R ₁ and R ₂ are any one of the following (i) to (v). The liquid crystal compound according to item 1. [Chemical 1] (A is an integer from 1 to 16, d, g, i are integers from 0 to 7, b, e, h, j are integers from 1 to 10, and f is 0 or 1
Indicates. However, b + d ≦ 16, e + f + g ≦ 16, h +
The condition of i ≦ 16 is satisfied. Y ₁ is a single bond, -O-, -C
OO -, - OCO- indicates, Y ₂ is -COO -, - CH
₂ O-is shown. It may be optically active. ) 5. A liquid crystal composition comprising at least one liquid crystal compound according to any one of claims 1 to 4. 6. The liquid crystal composition according to claim 5, wherein the content of the liquid crystal compound according to any one of claims 1 to 4 is 1 to 80% by weight. 7. The liquid crystal composition according to claim 5, wherein the content of the liquid crystal compound according to any one of claims 1 to 4 is 1 to 60% by weight. 8. The liquid crystal composition according to claim 5, wherein the content of the liquid crystal compound according to any one of claims 1 to 4 is 1 to 40% by weight. 9. The liquid crystal composition according to claim 5, which has a chiral smectic phase. 10. A liquid crystal device comprising the liquid crystal composition according to claim 5 arranged between a pair of electrode substrates. 11. The liquid crystal device according to claim 10, further comprising an alignment control layer provided on the electrode substrate. 12. The liquid crystal device according to claim 11, wherein the alignment control layer is a layer subjected to a rubbing treatment. 13. The liquid crystal element according to claim 10, wherein the pair of electrode substrates are arranged with a film thickness in which the spiral of liquid crystal molecules is released. 14. A display method using the liquid crystal composition according to claim 5. 15. A display device comprising the liquid crystal element according to claim 10. 16. The display device according to claim 15, further comprising a drive circuit for the liquid crystal element. 17. The display device according to claim 15, further comprising a light source.