JPH0797354A - Liquid crystal compound, liquid crystal composition containing the compound, liquid crystal element using the composition, and display method and display device using the element - Google Patents

Abstract

PURPOSE:To obtain a liquid crystal compound which is useful as a component for ferroelectric liquid crystal composition having high response speed, reduced temperature dependence and increased contrast. CONSTITUTION:A compound of formula I [R<1>, R<2> is H, a halogen, CN, a 1-20C straight, branched or cyclic alkyl (one of more CH2 in these groups may be substituted with O, S or CO unless it is adjacent to any heteroatom, further H may be repeated with F) or formula II ((m), (n), (p), (q) each is 1-16 where their total is 19 or less; Y<1> is a bond or O, CO, COO, CH=CH) where at least one is formula II; A<1> is A<2>, A<2>-X<1>-A<3>, A<2>-X<1>-A<3>-X<2>-A<4>; A<2>-A<4> are 1,4-phenylene, pyridine-2,5-diyl, 1,4-cyclohexylene which may be substituted; X<1>, X<2> are single bond, OCO, CH2O], for example, 2-[4-(6-propoxy-1H,1H,6H,6H-perfluorohexyloxy- carbonyl)phenyl]-6-hexylbenzothiazole.

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. Therefore, it is different from the optical modulation element used in the above-mentioned TN type liquid crystal. Differently, for example, the liquid crystal is aligned in the first optically stable state for one electric field vector and the second liquid crystal 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.

Further, when the operating temperature range as an actual display is, for example, about 5 to 40 ° C., the change in response speed is generally about 20 and the limit of adjustment by the drive voltage and frequency is exceeded at present. Is.

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.
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 -R ² (I)

[Wherein R ¹ and R ² are a hydrogen atom, halogen, CN, or a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms (one or 2 of the alkyl groups). One or more —CH ₂ — is —O—, —S—, —CO—, —CH (CN) —, —C under the condition that hetero atoms are not adjacent.
H = CH-, -C≡C- may be substituted,
The hydrogen atom in the alkyl group may be replaced by a fluorine _{atom), C m H 2m + 1} O (CH 2) n (CF 2) p (C
H ₂ ) _q −Y ¹ − (m, n, p, q are m + n + p + q ≦ 1
9 is an integer from 1 to 16 provided that 9 is satisfied, Y ¹ is a single bond, —O—, —CO—, —COO—,
-OCO -, - CH = CH - , - a C≡C- a is), at least one of R ^1, R ² _{is, C m H 2m + 1 O} (C
_{H 2) n (CF 2)} p (CH 2) q -Y 1 - is a. A ¹ is-
^{A 2 -, - A 2 -X} 1 -A 3 -, - A 2 -X 1 -A 3 -
X ² -A ⁴ - show the. A ² , A ³ , and A ⁴ are each independently an unsubstituted or one or two substituents (F, Cl, B
r, CH ₃ , CF 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, 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, Quinoxaline-2,6-diyl, quinoline-2,6-diyl, 2,6
-Naphthylene, indane-2,5-diyl, 2-alkylindan-2,5-diyl (the alkyl group is a linear or branched alkyl group having 1 to 18 carbon atoms),
Indanone-2,6-diyl, 2-alkylindanone-2,6-diyl (wherein the alkyl group has 1 to 18 carbon atoms)
Is a linear or branched alkyl group), 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), X ¹ , X ² is a single bond, -COO -, - OCO -, - CH 2 O -, - O
_{CH 2 -, - CH 2 CH} 2 -, - CH = CH -, - C≡C
− This liquid crystalline compound is a non-optically active compound. ] The liquid crystal compound represented by the formula, a liquid crystal composition containing at least one kind of the liquid crystal compound, a liquid crystal element comprising the liquid crystal composition arranged between a pair of electrode substrates, and a display method and display using the same. A device is provided.

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

(Ia) A ¹ represents —A ² —, A ² is unsubstituted or has one or two substituents (F, Cl, Br,
CH ₃ , CF ₃ or CN) 1,4-phenylene,
A liquid crystal compound selected from 1,4-cyclohexylene, quinoxaline-2,6-diyl, quinoline-2,6-diyl and 2,6-naphthylene.

[0026] (Ib) A ¹ is -A ² -X ¹ -A ³ - indicates, A ^2, at least one unsubstituted or 1 or 2 substituents (F in A ^3, Cl, Br, CH ₄ , CF ₃ or CN) 1,4-phenylene, 1,4-cyclohexylene, pyridine-2,5-diyl, pyrimidine-
A liquid crystal compound selected from 2,5-diyl.

(Ic) A ¹ is -A ² -X ¹ -A ³ -X
^2- A ⁴ —, at least one of A ² , A ³ and A ⁴ is unsubstituted or has 1 or 2 substituents (F, Cl, B
1, 4-phenylene having r, CH ₃ , CF ₃ or CN), the rest being unsubstituted or having 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN) 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4-cyclohexylene,
Thiazole-2,5-diyl, thiadiazole-2,5
-Zyle, indane-2,5-diyl, kumaran-2,
A liquid crystal compound selected from 5-diyl.

Further preferred compounds are the following (Iba)
~ (Ice).

(Iba) A ¹ is -A ² -X ¹ -A ^3-
Wherein A ² and A ³ are both unsubstituted or 1,4-phenylene having 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN), and X ¹ is a single group. Bond, -CO
_{O -, - CH 2 O -} , - CH 2 CH 2 -, - C≡C- a is liquid crystal compound.

(Ibb) A ¹ is -A ² -X ¹ -A ^3-
Wherein A ² is 1,4-phenylene which is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN), and A ³ is 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, benzoxazole-2,5- Diyl, benzothiazole-2,6-diyl, quinoxaline-2,6-diyl, quinoline-2,6-diyl, 2,6-naphthylene,
A liquid crystal compound selected from indane-2,5-diyl and coumarane-2,5-diyl, wherein X ¹ is a single bond.

(Ibc) A ¹ is -A ² -X ¹ -A ^3-
, A ² is pyridine-2,5-diyl, A ³
Is selected from 1,4-cyclohexylene, 2,6-naphthylene, indane-2,5-diyl and coumarane-2,5-diyl, and X ¹ is a liquid crystal compound having a single bond.

(Ibd) A ¹ is -A ² -X ¹ -A ^3-
, A ² is pyrimidine-2,5-diyl, and A ^2
3 is 1,4-cyclohexylene, 2,6-naphthylene,
A liquid crystal compound selected from indane-2,5-diyl and coumarane-2,5-diyl, wherein X ¹ is a single bond.

(Ica) A ¹ is -A ² -X ¹ -A ^3-
X ² -A ⁴ - ^{indicates, A 2, A 3, A} 4 are both unsubstituted or 1 or 2 substituents (F, Cl, Br, CH 3,
1,4-phenylene having CF ₃ or CN),
A liquid crystal compound in which at least one of X ¹ and X ² is a single bond.

(Icb) A ¹ is -A ² -X ¹ -A ^3-
X ² —A ⁴ —, ^two of A ² , A ³ , and A ⁴ are unsubstituted or one or two substituents (F, Cl, Br, CH
₃ , CF ₃ or CN) 1,4-phenylene, the remaining one is pyridine-2,5-diyl, pyrimidine-2,
5-diyl, 1,4-cyclohexylene, thiazole-
A liquid crystal compound selected from 2,5-diyl, thiadiazole-2,5-diyl, indane-2,5-diyl and coumarane-2,5-diyl, wherein X ¹ and X ² are single bonds.

(Icc) A ¹ is -A ² -X ¹ -A ^3-
X ² —A ⁴ —, A ² is pyridine-2,5-diyl, A ³ is unsubstituted or 1 or 2 substituents (F, C
1,4-phenylene having 1, 1, Br, CH ₃ , CF ₃ or CN), A ⁴ is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN). Selected from 1,4-phenylene, 1,4-cyclohexylene, thiophene-2,5-diyl and indane-2,5-diyl, X ¹ is a single bond, X ² is —OCO—, —OCH.
_{2 -, - CH 2 CH 2} - in which the liquid crystal compound.

(Icd) A ¹ is -A ² -X ¹ -A ^3-
X ² —A ⁴ —, A ² is pyrimidine-2,5-diyl, A ³ is unsubstituted or 1 or 2 substituents (F, C
1,4-phenylene having 1, 1, Br, CH ₃ , CF ₃ or CN), A ⁴ is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN). Selected from 1,4-phenylene, 1,4-cyclohexylene, thiophene-2,5-diyl and indane-2,5-diyl, X ¹ is a single bond, X ² is —OCO—, —OCH.
_{2 -, - CH 2 CH 2} - in which the liquid crystal compound.

(Ice) A ¹ is -A ² -X ¹ -A ^3-
X ² —A ⁴ —, A ² is 1,4-cyclohexylene, A ³ is unsubstituted or 1 or 2 substituents (F, C
1,4-phenylene having 1, 1, Br, CH ₃ , CF ₃ or CN), A ⁴ is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN). Selected from 1,4-phenylene, 1,4-cyclohexylene, thiophene-2,5-diyl and indane-2,5-diyl, X ¹ is a single bond, X ² is —OCO—, —OCH.
_{2 -, - CH 2 CH 2} - in which the liquid crystal compound.

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.

^One of R ¹ and R ² is (i) below,
The other is preferably selected from (i) to (vii).

[0040]

[Chemical 2]

(A is an integer of 1 to 16, m is 1 to 13)
, N, q are integers from 1 to 5, d, g, i are integers from 0 to 7, p, b, e, h are integers from 1 to 10, and f is 0.
Or 1 is shown. However, m + n + p + q ≦ 16, b + d ≦
16, the conditions of e + f + g ≦ 16 and h + i ≦ 16 are satisfied. Y ¹ represents a single bond, —O—, —COO—, or —OCO—. )

Next, an example of a method for synthesizing the liquid crystal compound represented by the general formula (I) will be shown.

[0043]

[Chemical 3]

(DCC represents dicyclohexylcarbodiimide. M, n, p, q, A ¹ and R ² are in accordance with the above general formula.)

Next, specific structural formulas of the liquid crystal compounds represented by formula (I) are shown in Tables 1 to 7. Hereinafter, the abbreviations used in the present invention represent the following groups.

[0046]

[Chemical 4]

[0047]

[Chemical 5]

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

[Table 3]

[0051]

[Table 4]

[0052]

[Table 5]

[0053]

[Table 6]

[0054]

[Table 7]

[0055]

[Table 8]

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) with 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 (II
Iaa) to (XIIdb). In addition, compounds (III) to (VI), preferable compounds (IIIa) to
(VIf), more preferred compound (IIIaa) to
(VIFA) R _'1, R' at least one of the _two in, but also compounds (VII), (VIII), preferred compounds (VIIa) ~ (VIIIb), more preferred compounds (VIIIba), (VIIIbb) in R '
₃ , at least one of R ′ ₄ , and compound (IX) to
(XII), preferred compounds (IXa) to (XII
d), more preferred compounds (IXba), (XIId
in _{b) R '5, R'} 6 of at least one of - (CH
_{2) E C G F 2G +} 1 (E: 0~10, G: 1~15 integer)
The compound of can be similarly used. Furthermore, liquid crystal compounds represented by the following general formulas (XIII) to (XVIII) can also be used.

[0059]

[Chemical 6]

[0060] wherein R _'7, R' ₈ is a hydrogen atom or a linear or branched alkyl group having 1 to 18 carbon atoms, one in the alkyl group or two or more -CH ₂ - Is -O-, -CO-, -OCO unless hetero atoms are adjacent to each other.
-, -COO-, -CH (CN)-, -C (CN) (C
H ₃₎ -, it may be replaced with. Hydrogen atoms in the alkyl group may be exchanged for fluorine atoms.

[0061] Further R _'7, R' ₈ is preferably i) to v
iii).

I) a straight-chain alkyl group having 1 to 15 carbon atoms

[0063]

[Chemical 7]

[0064] N, Q, R, T: 0 or 1 Y _{'7,
Y '8, Y' 9:} H or _{F A '4: Ph, Np} X' 7, X '8: single bond, -CO
O -, - OCO -, - CH 2 O -, - OCH 2 -

Preferred compounds of (XIII) are (X
IIIa).

[0066] _{R '7 - [Py2] -} [Ph] -OCO- [Tn] -R' 8 (XIIIa) Preferred compounds of (XVI) (XVIa), ( X
VIb).

[0067] _{R '7 - [Tz1] -} [Ph] -R' 8 (XVIa) R '7 - [PhY' 7] - [Tz1] - [PhY '8] -R' 8 (XVIb)

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

[0069] _{R '7 - [Boa2] -} [Ph] -O-R' 8 (XVIIa) R '7 - [Boa2] - [Np] -O-R' 8 (XVIIb)

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

[0071] _{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).

[0073] _{R '7 - [Tz1] -} [Ph] -O-R' 8 (XVIaa) R '7 - [Ph] - [Tz1] - [Ph] -R' 8 (XVIba) R '7 - [ Ph] - [Tz1] - [ Ph] -O-R '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.

[0075]

[Chemical 8]

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 preferably 1 to 80% by weight, preferably 1 to 60% by weight, and more preferably 1 to 40% by weight. 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, Preferably 1% by weight to 60
It is desirable to set the content 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 to a temperature of an isotropic liquid in a vacuum to obtain the device. It is preferable that the liquid crystal layer be sealed in a 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
1 μm, preferably 10 Å to 3000 Å, more preferably 10 Å to 1000 Å are suitable.

The two glass substrates 2 are held by the spacer 5 at arbitrary intervals. 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. Since FIG. 1 is a transmissive type, a 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 molecules 23 have an elongated shape and exhibit 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 device of the present invention in the display panel section and taking the data format as the image information having the scanning line address information shown in FIGS. 7 and 8 and the communication synchronizing means by the SYNC signal, the liquid crystal display device 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 unit 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.

[0091]

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 2- [4- (6-propoxy-1H, 1H, 6H, 6H
-Perfluorohexyloxycarbonyl) phenyl]
-6-Hexylbenzothiazole (Exemplified Compound No. 9
5) Manufacturing

(1) 6-propoxy-1H, 1H, 6
Production of H, 6H-perfluorohexanol

1H, 1 in a 2 liter three neck flask
50 g (190.8 mmol) of H, 6H, 6H-perfluoro-1,6-hexanediol and 511 ml of N, N-dimethylformamide were added and dissolved, and sodium hydride (60% inoil) 7.63 g (under stirring with ice cooling). 19
0.8 mmol) was added over 25 minutes. (Internal temperature 6
Then, the mixture was stirred at an internal temperature of 20 to 23 ° C for 1 hour.
Next, 32.4 g of propyl iodide (190.6
mmol) was added dropwise over 15 minutes. (Internal temperature 6 to 8 ° C) After that, the mixture was stirred at an internal temperature of 35 to 40 ° C for 4 hours and 30 minutes. The reaction was allowed to stand overnight then poured into 1.5 liters of cold water, adjusted to pH 1 with 5% hydrochloric acid and extracted with ether. The organic layer was washed 3 times with saturated brine, dried over anhydrous magnesium sulfate, and the solvent was evaporated. The residue was purified by silica gel column chromatography (eluent hexane / ethyl acetate: 4/1), and 20.1 g of 6-propoxy-1H, 1H, 6H, 6H-perfluorohexanol as a slightly yellow liquid (yield 34.7%). ) Got.

(2) 2- [4- (6-propoxy-1)
Preparation of H, 1H, 6H, 6H-perfluorohexyloxycarbonyl) phenyl] -6-hexylbenzothiazole

0.3 g (0.88 mmol) of 2- (4-carboxyphenyl) -6-hexylbenzothiazole
And 6-propoxy-1H, 1H, 6H, 6H-perfluorohexanol 0.27 g (0.89 mmol), dicyclohexylcarbodiimide 0.18 g (0.87 m
mol), 0.02 g of 4-dimethylaminopyridine and 6 ml of dichloromethane were placed in a 50 ml eggplant-shaped flask and stirred at room temperature for 24 hours. After the reaction was completed, the precipitated crystals were removed by filtration, and the filtrate was concentrated. The obtained crude product was purified by silica gel column chromatography (toluene / ethyl acetate = 50/1) and recrystallization (toluene / hexane) to give 2- [4- (6-propoxy-
0.30 g of 1H, 1H, 6H, 6H-perfluorohexyloxycarbonyl) phenyl] -6-hexylbenzothiazole was obtained (yield 54%, mp103.1).
C).

Example 2 2- [4- (5-butyloxy-1H, 1H, 5H, 5
H-perfluoropentyloxycarbonyl) phenyl] -5-nonylpyrimidine (Exemplified compound No. 70)
Manufacturing of

(1) 5-Butyloxy-1H, 1H, 5
Production of H, 5H-perfluoropentanol

1H, 1H, 5 in a 1 liter reaction vessel
H, 5H-perfluoro-1,5-pentanediol 4
8.3 g (228 mmol) and dry dimethylformamide (DMF) 735 ml were charged, and sodium hydride (60% in oil) 9.22 g (231 mmol) was charged.
Was added below 10.degree. After stirring at the same temperature for 10 minutes, the mixture was stirred at room temperature for 1 hour. Next, the mixture was cooled to 10 ° C. or lower and 31.4 g (229 mmol) of n-butyl bromide was added to 1
It was dripped in 0 minutes. Then, it stirred at 35 degreeC for 6 hours.
After completion of the reaction, the reaction solution was poured into 1 liter of water, and diluted hydrochloric acid was added to make the solution acidic. After adding sodium chloride to this to make it saturated, it was extracted with ethyl acetate. The extract was washed with brine, dried over anhydrous magnesium sulfate and dried.

After distilling off the solvent, distillation under reduced pressure (bp 86 ° C.)
˜98 ° C./4 torr) and silica gel column chromatography (hexane / ethyl acetate = 4/1) for purification, and 5-butyloxy-1H, 1H, 5H, 5.
H-perfluoropentanol 32.5 g (121 mm
ol) was obtained (53% yield).

(2) 2- [4- (5-butyloxy-1)
Production of H, 1H, 5H, 5H-perfluoropentyloxycarbonyl) phenyl] -5-nonylpyrimidine

0.35 g (1.07 mmol) of 2- (4-carboxyphenyl) -5-nonylpyrimidine and 5-
Butyloxy-1H, 1H, 5H, 5H-perfluoropentanol 0.30 g (1.12 mmol), dicyclohexylcarbodiimide 0.22 g (1.07 mmo)
l), 0.03 g of 4-dimethylaminopyridine and 8 ml of dichloromethane were placed in a 50 ml eggplant-shaped flask and stirred at room temperature for 14 hours. After the reaction was completed, the precipitated crystals were removed by filtration, and the filtrate was concentrated. The obtained crude product was purified by silica gel column chromatography (toluene / ethyl acetate = 100/1) and recrystallization (toluene / methanol) to give 2- [4- (5-butyloxy-
1H, 1H, 5H, 5H-perfluoropentyloxycarbonyl) phenyl] -5-nonylpyrimidine 0.3
7 g was obtained (yield 66%, mp 65.2 ° C.).

(Example 3) 4-pentyloxy-4'-biphenylcarboxylic acid 5-
Production of Butyloxy-1H, 1H, 5H, 5H-Perfluoropentyl (Exemplified Compound No. 71)

0.30 g (1.06 mmol) of 4-pentyloxy-4'-biphenylcarboxylic acid, 0.30 g (1.12 mmol) of 5-butyloxy-1H, 1H, 5H, 5H-perfluoropentanol and dicyclohexylcarbodiimide. 0.22 g (1.07 mmol),
0.03 g of 4-dimethylaminopyridine and 8 ml of dichloromethane were placed in a 50 ml eggplant-shaped flask, and 1
Stir for 4 hours. After the reaction was completed, the precipitated crystals were removed by filtration, and the filtrate was concentrated. The obtained crude product is subjected to silica gel column chromatography (toluene / ethyl acetate = 100/1) and recrystallized (toluene / methanol).
Purified by 5-pentyloxy-4′-biphenylcarboxylic acid 5-butyloxy-1H, 1H, 5H, 5H
-0.06 g of perfluoropentyl was obtained (yield 10
%).

Phase transition temperature (° C.)

[0106]

[Chemical 9]

Example 4 2- [4- (5-butyloxy-1H, 1H, 5H, 5
H-Perfluoropentyloxy) phenyl] -5-decylpyrimidine (Exemplified Compound No. 232)

(1) Trifluoromethanesulfonic acid 5-
Production of butyloxy-1H, 1H, 5H, 5H-perfluoropentyl

In a 100 ml eggplant-shaped flask, 1.34 g (5.0 mmol) of 5-butyloxy-1H, 1H, 5H, 5H-perfluoropentanol and 1.1 of pyridine were added.
9 g (15.0 mmol) was added and the mixture was cooled. Further, 2.82 g (10.
(0 mmol) was added dropwise, and the mixture was stirred at room temperature for 1 hour. After the reaction was completed, ice water was added, and the mixture was extracted with ethyl acetate. Extract 3
After washing with M-hydrochloric acid and water, anhydrous sodium sulfate was added and dried. The solvent was distilled off to obtain 1.78 g (4.45 mmol) of 5-butyloxy-1H, 1H, 5H, 5H-perfluoropentyl trifluoromethanesulfonate (yield 89%).

(2) 2- [4- (5-butyloxy-1)
H, 1H, 5H, 5H-perfluoropentyloxy)
Production of phenyl] -5-decylpyrimidine

A 50 ml eggplant-shaped flask was charged with 0.08 g (2.00 mmol) of sodium hydride [60%] and 3 ml of dimethylformamide (DMF). And 5-
Decyl-2- (4-hydroxyphenyl) pyrimidine (0.52 g, 1.66 mmol) was added, and the mixture was stirred at room temperature for 30 minutes. And trifluoromethanesulfonic acid 5-
Butyloxy-1H, 1H, 5H, 5H-perfluoropentyl 0.66 g (1.66 mmol) and DMF2m
1 of the mixed solution was added, and the mixture was stirred at 100 ° C. for 1 hour. After the reaction was completed, water was added and the mixture was extracted with ethyl acetate. Extract 3M
-After washing with hydrochloric acid and water, anhydrous sodium sulfate was added and dried. After distilling off the solvent, silica gel column chromatography (toluene) and recrystallization (methanol)
And purified to give 2- [4- (5-butyloxy-1
H, 1H, 5H, 5H-perfluoropentyloxy)
Phenyl] -5-decylpyrimidine 0.31 g (0.5
5 mmol) was obtained (33% yield).

Phase transition temperature (° C.)

[0113]

[Chemical 10]

Example 5 A liquid crystal composition A was prepared by mixing the following compounds in the following parts by weight.

[0115]

[Chemical 11]

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

[0117]

[Chemical 12]

(Example 6) Two 0.7 mm thick glass plates were prepared, an ITO film was formed on each glass plate, a voltage applying electrode was prepared, and SiO ₂ was vapor-deposited on this. It was an insulating layer. A silane coupling agent [KBM-602 manufactured by Shin-Etsu Chemical Co., Ltd.] 0.2% isopropyl alcohol solution was spun on a glass plate at a rotation speed of 2000 r. p. m spinner applied for 15 seconds to give a surface treatment. After that, heat drying treatment was performed at 120 ° C. for 20 minutes. Polyimide resin precursor [Toray Industries, Inc. SP-510] 1.5% on a glass plate with an ITO film that was further surface treated
Rotate the dimethylacetamide solution at a rotation speed of 2000 r. p. m
Was applied for 15 seconds with the spinner of. 60 minutes after film formation, 3
It was subjected to heat condensation baking treatment at 00 ° C. At this time, the film thickness of the coating film was about 250Å.

The coating film after firing was subjected to rubbing treatment with an acetate flocked cloth, then washed with isopropyl alcohol solution, and silica beads having an average particle diameter of 2 μm were dispersed on one glass plate, and then each rubbing treatment axis was applied. Were parallel to each other, and glass plates were stuck together using an adhesive sealant [Rixon Bond, Chisso Corporation], and dried by heating at 100 ° C. for 60 minutes to prepare a cell. The liquid crystal composition B mixed in Example 4 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 element, the optical response (transmission light amount change 0 to 90%) under the crossed Nicols is detected by applying the voltage of peak-to-peak voltage Vpp = 20V, and the response speed (hereinafter optical The response speed) was measured. The results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 551 μsec 295 μsec 164 μsec

Comparative Example 1 A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 except that the liquid crystal composition A mixed in Example 5 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 7 A liquid crystal composition C was prepared by mixing the following exemplary compounds in the weight parts shown below instead of the exemplary compounds mixed in Example 5.

[0124]

[Chemical 13]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 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 547 μsec 293 μsec 162 μsec

Example 8 A liquid crystal composition D was prepared by mixing the following exemplary compounds in the weight parts shown below instead of the exemplary compounds mixed in Example 5.

[0128]

[Chemical 14]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 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 544 μsec 292 μsec 162 μsec

Example 9 A liquid crystal composition E was prepared by mixing the following compounds in the following parts by weight.

[0132]

[Chemical 15]

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.

[0134]

[Chemical 16]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 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 601 μsec 310 μsec 168 μsec

Comparative Example 2 A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 except that the liquid crystal composition E mixed in Example 5 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 784 μsec 373 μsec 197 μsec

Example 10 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 9.

[0140]

[Chemical 17]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 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 610 μsec 321 μsec 177 μsec

Example 11 A liquid crystal composition H was prepared by mixing the following exemplary compounds in the following parts by weight instead of the exemplary compound mixed in Example 5.

[0144]

[Chemical 18]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 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 604 μsec 313 μsec 172 μsec

Example 12 A liquid crystal composition I was prepared by mixing the following compounds in the following parts by weight.

[0148]

[Chemical 19]

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.

[0150]

[Chemical 20]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 except that the liquid crystal composition J 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 509 μsec 257 μsec 133 μsec

Comparative Example 3 A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 except that the liquid crystal composition I mixed in Example 12 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 13 A liquid crystal composition K was prepared by mixing the following exemplary compounds in the following parts by weight instead of the exemplary compound mixed in Example 11.

[0156]

[Chemical 21]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 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 518 μsec 262 μsec 136 μsec

Example 14 A liquid crystal composition L was prepared by mixing the following exemplary compounds in the following parts by weight instead of the exemplary compound mixed in Example 5.

[0160]

[Chemical formula 22]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 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 498 μsec 254 μsec 132 μsec

As is clear from Examples 5 to 14, the ferroelectric liquid crystal devices containing the liquid crystal compositions B, C, D, F, G, H, 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 15) Instead of the polyimide resin precursor 1.5% dimethylacetamide solution used in Example 6, a polyvinyl alcohol resin [PUA, Kuraray Co., Ltd.] was used.
-117] A ferroelectric liquid crystal device 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 6. The results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 550 μsec 294 μsec 164 μsec

(Example 16) SiO used in Example 6
_A ferroelectric liquid crystal device was prepared in the same manner as in Example 6 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 6. . The results are shown below.

10 ° C. 25 ° C. 40 ° C. Response speed 540 μsec 288 μsec 160 μsec

As is apparent from Examples 15 and 16, the liquid crystal element containing the ferroelectric liquid crystal composition according to the present invention has a very low temperature operating characteristic which is much improved as in Example 6 even when the element structure is changed. In addition, the temperature dependence of the optical response speed is reduced.

Example 17 A liquid crystal composition M was prepared by mixing the following compounds in the following parts by weight.

[0170]

[Chemical formula 23]

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

[0172]

[Chemical formula 24]

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

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 silane coupling agent [KBM-602 manufactured by Shin-Etsu Chemical Co., Ltd.] 0.2% isopropyl alcohol solution was spun on a glass plate at a rotation speed of 2000 r. p. m spinner 15
It was applied for 2 seconds and surface-treated. After that, heat drying treatment was performed at 120 ° C. for 20 minutes. Furthermore, a polyimide resin precursor [Toray Industries, Inc. SP-510] 1.0% dimethylacetamide solution was spun on the surface-treated glass plate with an ITO film at a rotation speed of 3000 r. p. m spinner 15
It was applied for 2 seconds. 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 film was rubbed with an acetate flocked cloth and then washed with an isopropyl alcohol solution to give an average particle size of 1. After spraying silica beads of μm on one of the glass plates, the rubbing axes of the glass plates were made parallel to each other, and the glass plates were bonded together using an adhesive sealant [Rixon Bond of Chisso Corporation] for 60 minutes. A cell was prepared by heating and drying at 100 ° C. When the cell thickness of this cell was measured with a Berek phase plate, it was about 1.5 μm. A liquid crystal composition N 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 15 except that the liquid crystal composition M mixed in Example 15 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 18 A liquid crystal composition O was prepared by mixing the exemplified compounds shown below instead of the exemplified compound used in Example 17 in the following parts by weight.

[0178]

[Chemical 25]

A ferroelectric liquid crystal element was prepared in the same manner as in Example 17 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 17. did. As a result, the contrast is 2
It was 5.4.

Example 19 A liquid crystal composition P was prepared by mixing the exemplified compounds shown below instead of the exemplified compound used in Example 17 in the following parts by weight.

[0181]

[Chemical formula 26]

A ferroelectric liquid crystal element was prepared in the same manner as in Example 17 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 17. did. As a result, the contrast is 2
It was 2.1.

Example 20 A liquid crystal composition Q was prepared by mixing the exemplified compounds shown below instead of the exemplified compound used in Example 17 in the following parts by weight.

[0184]

[Chemical 27]

A ferroelectric liquid crystal device was prepared in the same manner as in Example 17 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 17. did. As a result, the contrast is 2
It was 1.9.

As is clear from Examples 17 to 20, the ferroelectric liquid crystal elements containing the liquid crystal compositions N, O, P and Q according to the present invention have high contrast during driving.

(Example 21) Instead of the polyimide resin precursor 1.0% dimethylacetamide solution used in Example 17, a polyvinyl alcohol resin [P manufactured by Kuraray Co., Ltd. was used.
VA-117] Example 17 except that a 2% aqueous solution was used.
A ferroelectric liquid crystal device was prepared in the same manner as in Example 17, and
As a result of measuring the contrast at the time of driving at 30 ° C. by the same method as described above, the contrast was 23.7.

(Example 22) Si used in Example 17
A ferroelectric liquid crystal device was prepared in the same manner as in Example 17 except that the alignment control layer was formed only by using a polyimide resin without using O ₂ , and was driven at 30 ° C. in the same manner as in Example 17. As a result of measuring the contrast, the contrast was 18.0.

(Example 23) Instead of the polyimide resin precursor 1.0% dimethylacetamide solution used in Example 17, 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 17 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 35.0.

As is clear from Examples 21, 22 and 23, the liquid crystal element containing the ferroelectric liquid crystal composition according to the present invention can obtain high contrast as in Example 17, even when the element structure is changed. There is. Further, as a result of detailed examination even when the drive waveform was changed, it was found that similarly a liquid crystal element containing the ferroelectric liquid crystal composition of the present invention could obtain higher contrast.

[0191]

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 (θ).

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 diagram showing a liquid crystal display device having a liquid crystal element utilizing ferroelectricity and a graphic 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 orientation control layer 5 Spacer 6 Lead wire 7 Power source 8 Polarizing plate 9 Light source I ₀ Incident light I Transmitted light 21a Substrate 21b Substrate 22 Liquid crystal having chiral smectic phase Layer 23 Liquid crystal molecule 24 Dipole moment (P⊥) 31a Voltage applying means 31b Voltage applying means 33a First stable state 33b Second stable state 34a Upward dipole moment 34b Downward dipole moment Ea Upward electric field Eb Downward Electric field 101 Ferroelectric liquid crystal display device 102 Graphic controller 103 Display panel 104 Scan line drive circuit 105 Information line drive circuit 106 Decoder 107 Scan signal generation circuit 108 Shift register 109 Line memory 110 Information signal generation circuit 11 Drive control circuit 112 GCPU 113 host CPU 114 VRAM

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C07C 25/18 25/24 43/14 255/49 321/12 C07D 213/30 213/65 215 / 20 237/08 237/14 239/26 239/34 241/12 241/18 241/42 241/44 263/56 277/22 277/34 285/12 285/13 307/79 333/16 333/38 405 / 04 213 417/04 417/06 417/12 C09K 19/12 9279-4H 19/34 9279-4H 19/46 9279-4H G02F 1/13 500 9225-2K C07D 285/12 C (72) Inventor Gate Goji Kano 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yoko Yamada 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (18)

[Claims] 1. A liquid crystalline compound represented by the following general formula (I): R ¹ -A ¹ -R ² (I) [In the formula, R ¹ and R ² are a hydrogen atom, halogen, CN, or a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms ( One or more-in the alkyl group
CH ₂ — is —O—, —S under the condition that hetero atoms are not adjacent to each other.
-, -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), C
_{m H 2m + 1 O (CH} 2) n (CF 2) p (CH 2) q -Y 1 -
(M, n, p, and q are integers from 1 to 16 provided that m + n + p + q ≦ 19 is satisfied, Y ¹ is a single bond, —O—, —CO—, —COO—, —OCO—, −
CH = CH -, - a C≡C- a is), R ^1, R ²
At least one of C _m H _{2m + 1} O (CH ₂ ) _n (CF ₂ )
^{_{p (CH 2) q -Y 1}} - it is a. A ¹ is -A ^2- , -A ^{2
-X 1 -A 3 -, - A} 2 -X 1 -A 3 -X 2 -A 4 - shows a. A ² , A ³ , and A ⁴ are each independently an unsubstituted or one or two 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, 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, benzo Oxazole-2,6-
Diyl, benzothiazole-2,5-diyl, benzothiazole-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 to 18 carbon atoms
Is a linear or branched alkyl group), indanone-2,6-diyl, 2-alkylindanone-2,6-
Diyl (the 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 carbon atom) Is a linear or branched alkyl group having a number of 1 to 18), X ¹ and X ² are single bonds,
COO -, - OCO -, - CH 2 O -, - OCH 2 -, -
_{CH 2 CH 2 -, - CH} = CH -, - is C≡C-. This liquid crystalline compound is a non-optically active compound. ] 2. The liquid crystal compound according to claim 1, wherein the liquid crystal compound represented by the general formula (I) is any one of the following (Ia) to (Ic). (Ia) A ¹ represents —A ² —, A ² is unsubstituted or has one or two substituents (F, Cl, Br, CH ₃ , CF _3).
Or a CN) -containing liquid crystalline compound (Ib) A ¹ selected from 1,4-phenylene, 1,4-cyclohexylene, quinoxaline-2,6-diyl, quinoline-2,6-diyl, and 2,6-naphthylene. There -A ² -X ¹ -A ³ - indicates, a ^2,
At least one of A ³ is unsubstituted or has 1,4-phenylene, 1,4-cyclohexylene, pyridine- having 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN). 2,5-diyl, the liquid crystal compound selected from pyrimidine-2,5-diyl (Ic) a ¹ is ^{-A 2 -X 1 -A 3 -X 2} -A 4 - indicates, a ^2, a ^3, At least one of A ⁴ is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH ₃ , C
F ₃ or CN) 1,4-phenylene having a rest 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, thiazole-2,
Liquid crystalline compound selected from 5-diyl, thiadiazole-2,5-diyl, indane-2,5-diyl and coumarane-2,5-diyl 3. The liquid crystal compound (Iba) A ^{1 according} to claim 1, wherein the liquid crystal compound represented by the general formula (I) is any one of the following (Iba) to (Ice). -A ² -X ¹ -A ³ - indicates,
A ² and A ³ are both unsubstituted or 1,4-phenylene having 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN), X ¹ is a single bond, − COO
_{-, - CH 2 O -,} - CH 2 CH 2 -, - C≡C- a is a liquid crystal compound (Ibb) A ¹ is -A ² -X ¹ -A ³ - indicates, A ²
Is an unsubstituted or one or two substituents (F, Cl, B
r, CH ₃ , CF ₃ or CN) and A ³ is 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, benzoxazole-2,5-diyl, benzothiazole-2,6-
Diyl, quinoxaline-2,6-diyl, quinoline-
2,6-diyl, 2,6-naphthylene, indane-2,
5-diyl, coumarin-2,5-diyl, X
¹ is a single bond liquid crystal compound (Ibc) A ¹ represents -A ² -X ¹ -A ^3- , and A ²
Is pyridine-2,5-diyl, A ³ is 1,4-cyclohexylene, 2,6-naphthylene, indane-2,
5-diyl, coumarin-2,5-diyl, X
¹ is a liquid crystal compound (Ibd) A ¹ which is a single bond represents -A ² -X ¹ -A ^3- , and A ²
Is pyrimidine-2,5-diyl and A ³ is 1,4-
Cyclohexylene, 2,6-naphthylene, indane-
Liquid crystal compound (Ica) A ¹ selected from 2,5-diyl and coumarane-2,5-diyl, wherein X ¹ is a single bond, is —A ² —X ¹ —A ³ —X ² —A ⁴ —
Where A ² , A ³ and A ⁴ are all unsubstituted or one or two substituents (F, Cl, Br, CH ₃ , CF ₃ or C
N-)-containing 1,4-phenylene, wherein at least one of X ¹ and X ² is a single bond, (Icb) A ¹ is -A ² -X ¹ -A ³ -X ² -A ⁴ −
Wherein ^two of A ² , A ³ and A ⁴ are unsubstituted or have 1,4-phenylene having 1 or 2 substituents (F, Cl, Br, CH ₃ , CF ₃ or CN), The remaining one is pyridine-2,5-diyl, pyrimidine-2,5-diyl,
1,4-cyclohexylene, thiazole-2,5-diyl, thiadiazole-2,5-diyl, indane-2,
5-diyl, coumarin-2,5-diyl, X
^1, X ² is a liquid crystal compound is a single bond (Icc) A ¹ is ^{-A 2 -X 1 -A 3 -X 2} -A 4 -
, A ² is pyridine-2,5-diyl, A ³ is unsubstituted or 1 or 2 substituents (F, Cl, Br, CH
_3, CF ₃ or CN) to a 1,4-phenylene, A ⁴
Is an unsubstituted or one or two substituents (F, Cl, B
r, CH ₃ , CF ₃ or CN), 1,4-phenylene, 1,4-cyclohexylene, thiophene-2,5-
Selected from diyl and indane-2,5-diyl, X ¹ is a single bond, X ² is —OCO—, —OCH ₂ —, —CH ₂ CH.
₂ - is a liquid crystal compound (Icd) A ¹ is ^{-A 2 -X 1 -A 3 -X 2} -A 4 -
, A ² is pyrimidine-2,5-diyl, A ³ is unsubstituted or 1 or 2 substituents (F, Cl, Br, C
H ₃ , CF ₃ or CN) 1,4-phenylene, A
⁴ is unsubstituted or 1 or 2 substituents (F, Cl, B
r, CH ₃ , CF ₃ or CN), 1,4-phenylene, 1,4-cyclohexylene, thiophene-2,5-
Selected from diyl and indane-2,5-diyl, X ¹ is a single bond, X ² is —OCO—, —OCH ₂ —, —CH ₂ CH.
₂ - ² liquid crystal compound (Ice) A ¹ is -A is -X ¹ -A ³ -X ² -A ⁴ -
Where A ² is 1,4-cyclohexylene, A ³ is unsubstituted or has 1 or 2 substituents (F, Cl, Br, CH
_3, CF ₃ or CN) to a 1,4-phenylene, A ⁴
Is an unsubstituted or one or two substituents (F, Cl, B
r, CH ₃ , CF ₃ or CN), 1,4-phenylene, 1,4-cyclohexylene, thiophene-2,5-
Selected from diyl and indane-2,5-diyl, X ¹ is a single bond, X ² is —OCO—, —OCH ₂ —, —CH ₂ CH.
₂ -is a liquid crystalline compound 4. At least one of A ² and A ³ of the liquid crystal compound represented by the general formula (I) is 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, quinoxaline-2,6-diyl, quinoline-2,6-diyl, indane-2,5-diyl, 2-alkylindan-2,5-diyl (wherein the alkyl group has 1 to 18 carbon atoms) A chain or branched alkyl group), indanone-2,6-diyl, 2-alkylindanone-2,6-diyl (the alkyl group is a linear or branched alkyl group having 1 to 18 carbon atoms) Group), coumarane-2,5-diyl, 2-alkyl coumarane-2,5
2. A liquid crystalline compound according to claim 1, which is selected from -diyl (the alkyl group is a linear or branched alkyl group having 1 to 18 carbon atoms). 5. ^One of R ¹ and R ² of the liquid crystal compound represented by the general formula (I) is the following (i), and the other is any one of (i) to (vii). The liquid crystalline compound according to any one of claims 1 to 4, which is characterized in that. [Chemical 1] (A is an integer from 1 to 16, m is an integer from 1 to 13, n,
q is an integer from 1 to 5, d, g, i are integers from 0 to 7,
p, b, e, and h are integers from 1 to 10, and f is 0 or 1. However, m + n + p + q ≦ 16, b + d ≦ 16, e +
The conditions of f + g ≦ 16 and h + i ≦ 16 are satisfied. Y ¹ represents a single bond, —O—, —COO—, or —OCO—. ) 6. A liquid crystal composition comprising at least one liquid crystal compound according to claim 1. 7. The liquid crystal composition according to claim 6, wherein the content of the liquid crystal compound represented by the general formula (I) is 1 to 80% by weight. 8. The liquid crystal composition according to claim 6, wherein the content of the liquid crystal compound represented by the general formula (I) is 1 to 60% by weight. 9. The liquid crystal composition according to claim 6, wherein the content of the liquid crystal compound represented by the general formula (I) is 1 to 40% by weight. 10. The liquid crystal composition according to claim 6, which has a chiral smectic phase. 11. A liquid crystal device comprising the liquid crystal composition according to claim 6 disposed between a pair of electrode substrates. 12. The liquid crystal device according to claim 11, further comprising an alignment control layer provided on the electrode substrate. 13. The liquid crystal device according to claim 12, wherein the alignment control layer is a layer subjected to a rubbing treatment. 14. The liquid crystal device according to claim 11, wherein the pair of electrode substrates are arranged so as to have a film thickness capable of releasing the spiral of liquid crystal molecules. 15. A display method using the liquid crystal composition according to claim 6. 16. A display device comprising the liquid crystal element according to claim 11. 17. The display device according to claim 16, further comprising a drive circuit for the liquid crystal element. 18. The display device according to claim 16, further comprising a light source.