JPH07118255A - Optically active compound, liquid crystal composition containing the same, liquid crystal element having the same composition, display device using the same element and display method using the same composition - Google Patents

Abstract

PURPOSE:To obtain a new optically active compound useful for a liquid crystal element, display device, etc., providing a liquid crystal composition having a high response rate, showing a ferroelectric chiral smectic phase, comprising a compound containing plural rings of an aromatic ring, a heterocyclic ring, etc., in the molecule. CONSTITUTION:A new optically active compound is shown by formula l [R1 and R2 are H, halogen, CH, group of formula II, 1-18C (substituted) alkyl, etc.; X1 and X2 are single bond, COO, OOC, CH2O, OCH2, CH2CH2 or CidenticalC; A1 to A3 are group of formula III to group of formula XXI (Y1 and Y2 are H, F, Cl, Br, CH3, CF3 or CN; R3 to R5 are Hor 1-18C alkyl; Z is O or S)]. This compound provides a liquid crystal composition having a high response rate, effectively reduced temperature dependence of the response rate, effectively controlled spiral pitch of cholesteric phase, showing ferroelectric chiral smectic phase, and is useful for a liquid crystal element, display device, etc.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention uses a novel optically active compound, a liquid crystal composition containing the same, a liquid crystal device having the liquid crystal composition, a display method using the device, and the above liquid crystal composition. More specifically, the present invention relates to a display device, a novel liquid crystal composition having improved response characteristics to an electric field, a liquid crystal display device using the same, a liquid crystal device used in a liquid crystal-optical shutter, and the liquid crystal device used for display. Display device.

[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 devices currently in practical use are, for example, “Applied Physics Lett” by M. Schadt and W. Helfrich.
ers "Vo.18, No.4 (1971.2.15) P.127-128" Voltage De
pendent Optical Activity of a Twisted Nematic Liqu
TN (Twisted Nematic) type liquid crystal shown in "id Crystal") is used.

These are based on the dielectric alignment effect of liquid crystals, 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 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 panel display, the drive by the simple matrix method is the most effective in consideration of price and productivity. 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 for driving thereof, an address signal is sequentially and selectively selected and applied to the scan electrode group, Employs a time-division drive system in which a predetermined information signal is synchronized with an address signal and selectively applied in parallel.

[0004]

However, if the above-mentioned TN type liquid crystal is adopted for the element 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 not selected. A finite electric field is applied to a region (so-called “half-selection point”) where is selected. If the difference between the voltage applied to the selection point and the voltage applied to the semi-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 the intermediate voltage value, the display element is Although it operates normally, when the number of scanning lines (N) is increased, the time (duty ratio) that an effective electric field is applied to one selection point while scanning the entire screen (1 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 repeating scanning becomes smaller as the number of scanning lines increases, and as a result, the image contrast is lowered or Crosstalk is an unavoidable problem. Such a phenomenon is caused by a liquid crystal having no bistability (a stable state in which the liquid crystal molecules are aligned horizontally with respect to the electrode surface, and is aligned vertically only while an electric field is effectively applied. Is a problem that is essentially unavoidable when (1) is driven by utilizing the temporal accumulation effect (that is, repeated scanning). In order to improve this point, the voltage averaging method,
The two-frequency driving method and the multi-matrix method have already been proposed, but none of them is sufficient, and the increase in the screen size and the density of the display element is stopped because the number of scanning lines cannot be increased sufficiently. It is the current situation.

In order to improve the drawbacks of the conventional liquid crystal device, the use of a bistable liquid crystal device has been proposed by Clark and Lagerwall (Japanese Patent Laid-Open No. 56-107216). Gazette, U.S. Pat. No. 4,367,924). As a bistable liquid crystal, a chiral smectic C phase (SmC ^* phase) is generally used.
Alternatively, a ferroelectric liquid crystal having an H phase (SmH ^* 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. In contrast, for example, the liquid crystal is aligned in the first optical stable state with respect to one electric field vector and the liquid crystal is aligned in the second optical stable state with respect to the other electric field vector. Further, this type of liquid crystal has a property (bistability) of taking one of the above two stable states in response to an applied electric field and maintaining that state when no electric field is applied.

In addition to the above-mentioned 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 directly act to induce the transition of the alignment state, which is 3 to 4 orders faster than the response speed due to the action of the dielectric anisotropy and the electric field. Thus, the ferroelectric liquid crystal potentially has extremely excellent characteristics, and by utilizing such characteristics, it is quite essential to many of the problems of the conventional TN type element described above. Significant improvement. In particular, it is expected to be applied to high-speed optical optical shutters, high-density, large-screen displays. For this reason, although extensive research has been conducted on liquid crystal materials having ferroelectricity, the ferroelectric liquid crystal materials developed to date are sufficient for use in liquid crystal elements, including low-temperature operating characteristics and high-speed response. It is hard to say that it has characteristics.

Here, the response time τ and the magnitude of spontaneous polarization P
The relationship of the following formula (II) exists between s and the viscosity η. (However, E is the applied electric field.) Therefore, the following method can be used to increase the response speed. (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, etc. desirable. Therefore, actually, it is 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 capable of assuming a bistable state. Further, even if the spontaneous polarization is unnecessarily increased, the viscosity tends to increase accordingly, and as a result, it is considered that the response speed does not become so fast. When the temperature range used as an actual display is, for example, about 5 to 40 ° C., the change in response speed in the temperature range is generally 20.
The current situation is that the limit of adjustment by the drive voltage and frequency is exceeded. As described above, in order to put a ferroelectric liquid crystal device into practical use, a liquid crystal composition having a low viscosity, a high-speed response, and a chiral smectic phase with a small temperature dependence of the response speed is required. It

Further, in order to put the ferroelectric liquid crystal device into practical use, it is necessary to satisfy the uniform orientation on a large screen.
As a method of aligning a ferroelectric liquid crystal, a molecular layer composed of a plurality of molecules forming a smectic liquid crystal over a large area can be aligned uniaxially along its normal line, and the manufacturing process is also What can be realized by a simple rubbing process is desirable. The ferroelectric liquid crystal composition generally needs to have a cholesteric phase and have a long helical pitch in the cholesteric phase in order to easily orientate by rubbing treatment.

Therefore, the object of the present invention is to improve the response speed and to reduce the temperature dependence of the response speed so that the above-mentioned ferroelectric liquid crystal device can be put to practical use. And an optically active compound effective for controlling the helical pitch in a cholesteric phase, a liquid crystal composition containing the same, particularly a liquid crystal composition exhibiting a ferroelectric chiral smectic phase, and a liquid crystal using the liquid crystal composition element,
It is to provide a display method using the element and a display device using the liquid crystal composition.

[0012]

The above object can be achieved by the present invention described below. That is, the present invention provides an optically active compound represented by the following general formula (I), a liquid crystal composition containing at least one of the compounds, and the liquid crystal composition disposed between a pair of electrode substrates. And a display method using the device, and a display device using the liquid crystal composition.

[Chemical 40](In the formula, R ₁And R ₂Is a hydrogen atom, halogen, CN,

[Chemical 41]Alternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
The hydrogen atom may be exchanged for a fluorine atom. X ₁
And X ₂Is a single bond, -COO-, -OOC-, -CH₂
O-, -OCH₂-, -CH ₂CH ₂-Or-C≡C-
Show, A ₁, A ₂And A ₃Are single bonds, or
Indicates either.

[Chemical 42]

R ₃, R _Four, R _FiveAnd R ₆Are hydrogen atoms and
Is a linear or branched alkyl having 1 to 18 carbon atoms
Indicates a group. Y₁And Y₂Is H, F, Cl, Br, C
H ₃, CF ₃Or CN. Z represents O or S. However
Then A ₁, A ₂And A ₃At least one of
It is either, and the other two can be a single bond at the same time.
Absent.

[Chemical 43]

Also, -A ₁-X ₁-A ₂-X ₂-A ₃-Is

[Chemical 44]Then X ₁And X ₂Is -COO- or -CH ₂O-
There is no. Also, -A ₁-X ₁-A ₂-X ₂-A ₃-Is

[Chemical formula 45]Then X ₁And X ₂Is -OOC- or -OCH ₂-In
There is no.

A ₁Or-A ₁-X ₁-A ₂− Is the following formula
In case of R ₁And R _FiveAre different from each other,

[Chemical formula 46]A ₃Or A ₂-X ₂-A ₃Where R is ₂And R ₆Are mutual
Very different.

[Chemical 47] In addition, * shows that it is optically active. )

[0016]

The present inventors have made detailed investigations on a novel optically active compound having a coumaran skeleton represented by the general formula (I). As a result, a ferroelectric chiral smectic liquid crystal composition containing the optically active compound of the present invention and According to the liquid crystal device using it, various characteristics such as good alignment property by adjusting the cholesteric pitch, high-speed response and reduction of temperature dependence of response speed are improved, and good display properties are obtained. The findings led to the present invention. Further, the optically active compound of the present invention has excellent compatibility with other optically active compounds, and has spontaneous polarization as a liquid crystal mixture, chiral smectic C pitch, temperature range for taking a liquid crystal phase, optical anisotropy, tilt angle and high strength. It can also be usefully used for adjusting the dielectric anisotropy and the like.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to preferred embodiments. Among the optically active compounds of the present invention represented by the general formula (I), the temperature range of the liquid crystal phase,
From the viewpoint of miscibility and orientation, the compounds represented by (Ia) to (Iu), (Iv) and (Iw), which are preferably cyclic groups, are mentioned.

[0018]

[Chemical 48]

[0019]

[Chemical 49]

[0020]

[Chemical 50]

[0021]

[Chemical 51]

(Where R is ₁And R ₂Is a hydrogen atom, halogen
N, CN,

[Chemical 52]Alternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
Hydrogen atoms may be exchanged for fluorine atoms. X ₁Over
And X ₂Is a single bond, -COO-, -OOC-, -CH₂O
-, -OCH₂-, -CH₂CH₂− Or −C≡C−
Then A ₁Is one of the following formulas,

[Chemical 53]

A ₂And A ₃Are A respectively ₁Or

[Chemical 54]Indicates. R ₃, R _Four, R _FiveAnd R ₆Are hydrogen atom or charcoal, respectively
Indicates a linear or branched alkyl group having 1 to 18 elementary atoms
You Y₁And Y₂Is H, F, Cl, Br, CH ₃, CF ₃
Or CN. Z represents O or S. However, R ₁And R _Five
Are different from each other, R ₂And R ₆Are also different from each other. In addition, * is light
It shows that it is academically active. )

[0024]

[Chemical 55]

(In the formula, R ₁And R ₂Is a hydrogen atom, halogen
N, CN,

[Chemical 56]Alternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
The hydrogen atom may be exchanged for a fluorine atom. X ₂
Is a single bond, -OOC-, -OCH₂-, -CH₂CH₂
-Or-C represents C-, and X₁Is X₂, -COO-, or
Is -CH₂Indicates O-. R₆Is the number of hydrogen or carbon atoms
Represents a linear or branched alkyl group of 1 to 18. Y
₁And Y₂Is H, F, Cl, Br, CH₃, CF₃Or C
Represents N. However, R₂And R₆Are different from each other, * means optical activity
Represents sex. )

Further, among the compounds represented by the above (Ia) to (Iw), more preferable compound is (Ia
a) to (Iwg). These optically active compounds are compounds having a small number of polar bonds and can be expected to have a low viscosity in addition to the above-mentioned temperature range of the liquid crystal phase, miscibility and orientation.

[0027]

[Chemical 57]

[0028]

[Chemical 58]

[0029]

[Chemical 59]

[0030]

[Chemical 60]

[0031]

[Chemical formula 61]

[0032]

[Chemical formula 62]

[0033]

[Chemical formula 63]

[0034]

[Chemical 64]

[0035]

[Chemical 65]

[0036]

[Chemical formula 66]

[0037]

[Chemical formula 67]

[0038]

[Chemical 68](In the formula, R ₁And R ₂Is a hydrogen atom, halogen, CN,

[0039]

[Chemical 69]Alternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
Hydrogen atoms may be exchanged for fluorine atoms. R _FiveOver
And R ₆Are each a hydrogen atom or a straight chain having 1 to 18 carbon atoms.
A branched or branched alkyl group. Y₁And Y₂Is H,
F, Cl, Br, CH ₃, CF ₃Or CN. However,
R ₁And R _FiveIs different from ₂And R ₆Are also different from each other.
In addition, * shows that it is optically active. )

[0040]

[Chemical 70]

[0041]

[Chemical 71]

(In the formula, R ₁And R ₂Is a hydrogen atom, halogen
N, CN,

[Chemical 72]Alternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
Hydrogen atoms may be exchanged for fluorine atoms. R
₆Is a hydrogen atom or a linear or branched chain having 1 to 18 carbon atoms.
It is a branched alkyl group. Y₁And Y₂Is H, F, C
l, Br, CH ₃, CF ₃Or CN. However, R ₂
And R ₆Is different from, and * indicates that it is optically active.
You )

Further, R ₁ and R ₂ are preferably selected from the following.

[Chemical formula 73](However, a is an integer of 1 to 17, d, g and i
Is an integer from 0 to 7 and b, e and h are 1 to 8
Some integer, f and k are 0 or 1, j is an integer from 1 to 15
Number, X ₃Is a single bond, -O-, -OOC- or -COO-
Indicates. ) R ₁And R ₂Is more preferably (i), (ii), (v) and
And (vi), more preferably (i) or (vi)
Is. X ₃Is preferably a single bond or -O-,
More preferably, it is a single bond.

Next, a method for synthesizing the optically active compound represented by the general formula (I) will be described. The general formula (I)
As an example of an intermediate for producing the optically active compound of the present invention represented by the following formula, an optically active 2-alkylcoumarane-5-of the following general formula (I ″) shown in Japanese Patent Application No. Examples thereof include carboxylic acids.

[Chemical 74] (R is a linear or branched alkyl group having 1 to 18 carbon atoms, and * indicates optically active.)

A preferred example of the method for synthesizing the optically active compound of the present invention represented by the general formula (I) using the above compound (I ″) is shown below.

[Chemical 75]

However, R ₁, R ₂, A ₁, A ₂, X ₁And X
₂Is as defined in the general formula (I). E ₂,
E ₃, E _FourAnd E _FiveIs X ₂When is not a single bond, X ₂The conclusion
A group suitable for becoming a child and A ' ₂Is A ₃And
It Also, X ₂Is a single bond, E ₂, E ₃, E _Four, E
_FiveAnd A ' ₂Is A after reaction ₂It is a suitable group to become.

The preferred specific structural formula of the optically active compound of the present invention represented by the general formula (I) is shown below.

[0048]

[Chemical 76]

[0049]

[Chemical 77]

[0050]

[Chemical 78]

[0051]

[Chemical 79]

[0052]

[Chemical 80]

[0053]

[Chemical 81]

[0054]

[Chemical formula 82]

[0055]

[Chemical 83]

[0056]

[Chemical 84]

[0057]

[Chemical 85]

[0058]

[Chemical 86]

[0059]

[Chemical 87]

[0060]

[Chemical 88]

[0061]

[Chemical 89]

[0062]

[Chemical 90]

[0063]

[Chemical Formula 91]

The liquid crystal composition of the present invention is characterized by containing at least one optically active compound represented by the general formula (I) as described above. It can also be obtained by mixing at least one optically active compound represented by the general formula (I) with at least one other liquid crystal compound in an appropriate ratio. The liquid crystal composition according to the present invention is preferably a ferroelectric liquid crystal composition, particularly a ferroelectric chiral smectic liquid crystal composition. Preferred examples of other liquid crystal compounds used in the present invention are shown below by the general formulas (III) to (XIII).

[0065]

[Chemical Formula 92]

[0066]

[Chemical formula 93]

[0067]

[Chemical 94]

[0068]

[Chemical 95]

Here, R ₁ 'and R ₂ ' have 1 to 18 carbon atoms.
Is a linear or branched alkyl group, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may be replaced by —CH halogen —. Furthermore, -CH ₂ binds directly X ₁ 'and X _2' - not one or adjacent excluding group two or more -CH ₂ - groups may be replaced by the following equation.

[Chemical 96] Provided that when R ₁ ′ or R ₂ ′ is a halogenated alkyl in which one CH ₂ group is replaced by the following formula, R ₁ ′ or R ₂ ′
Is not a single bond to the ring.

[Chemical 97]

Preferred values for R ₁ 'and R ₂ ' are shown below. i) a straight-chain alkyl group having 1 to 15 carbon atoms

[Chemical 98] p: an integer of 0 to 5, q: an integer of 2 to 11 may be optically active.

[0071]

[Chemical 99] r: integer of 0 to 6, s: 0 or 1, t: 1 to 1
Integer of 4 Optically active.

[Chemical 100] u: 0 or 1, v: an integer from 1 to 16

[0072]

[Chemical 101] w: integer of 1 to 15 may be optically active.

[Chemical 102] x: integer of 0 to 2, y: integer of 1 to 15

[0073]

[Chemical 103] z: an integer from 1 to 15

[Chemical 104] A: integer of 0 to 2; B: integer of 1 to 15 It may be optically active.

[0074]

[Chemical 105] C: integer of 0 to 2, D: integer of 1 to 15 may be optically active. x) H xi) F

More preferable compounds (IIIa) to (IIId) include (IIIaa) to (IIIdc).

[0076]

[Chemical formula 106]

[0077]

[Chemical formula 107]

More preferable compounds (IVa) to (IVc) include the following (IVaa) to (IVcb).

[Chemical 108]

More preferable compounds of (Va) and (Vb) include the following (Vaa) to (Vbf).

[0080]

[Chemical 109]

[0081]

[Chemical 110]

More preferable compounds (VIa) to (VIf) include the following (VIaa) to (VIfa).

[0083]

[Chemical 111]

[0084]

[Chemical 112]

More preferable compounds of (VII) include the following (VIIa) and (VIIb).

[Chemical 113]

More preferred compounds of (VIII) include the following (VIIIa) and (VIIIb).

[Chemical 114]

Further preferred compounds of (VIIIb) are:
The following (VIIIba) and (VIIIbb) are mentioned.

[Chemical 115]

Where R ' ₃And R ' _FourHas 1 to 18 carbon atoms
A linear or branched alkyl group, in which the alkyl group is
One or two or more -CH that are not adjacent₂-Group is
It may be replaced by -CH halogen-.
Furthermore, X ' ₁And X ' ₂-CH directly bonded to₂-Excluding groups
One or two or more non-adjacent -CH₂-Group is below
It may be replaced by a notation.

[Chemical formula 116] Provided that when R ₃ ′ or R ₄ ′ is a halogenated alkyl in which one —CH ₂ — group is replaced with —CH halogen—
R ₃ 'or R ₄ ' are not bonded to the ring by a single bond.

Further, preferable examples of R ₃ 'and R ₄ ' are shown below. i) a straight-chain alkyl group having 1 to 15 carbon atoms

[Chemical 117] p: an integer of 0 to 5, q: an integer of 2 to 11 may be optically active.

[Chemical 118] r: integer of 0 to 6, s: 0 or 1, t: 1 to 1
Integer of 4 Optically active.

[0090]

[Chemical formula 119] u: 0 or 1, v: an integer from 1 to 16

[Chemical 120] w: integer of 1 to 15 may be optically active.

[0091]

[Chemical 121] A: integer of 0 to 2; B: integer of 1 to 15 It may be optically active.

[Chemical formula 122] C: integer of 0 to 2, D: integer of 1 to 15 may be optically active.

[0092]

[Chemical 123]

[0093]

[Chemical formula 124]

[0094]

[Chemical 125]

Preferred compounds of (IX) are the following (IX
a) to (IXc).

[Chemical formula 126]

Preferred compounds of (X) are the following (X
a) and (Xb).

[Chemical 127]

Preferred compounds of (XII) are the following (X
IIa)-(XIIf).

[Chemical 128]

Preferred compounds of (XIII) include the following (XIIIa) to (XIIIe).

[Chemical formula 129]

More preferred compounds (IXa) to (IXc) include the following (IXaa) to (IXcc).

[0100]

[Chemical 130]

[0101]

[Chemical 131]

More preferable compounds of (Xa) and (Xc) include the following (Xaa) to (Xbb).

[Chemical 132]

More preferred compounds of (XI) include the following (XIa) to (XIg).

[Chemical 133]

More preferable compounds (XIIa) to (XIIf) include the following (XIIaa) to (XIIfc).

[0105]

[Chemical 134]

[0106]

[Chemical 135]

Here, R ₅ 'and R ₆ ' have 1 to 18 carbon atoms.
A linear or branched alkyl groups, -CH ₂ binds directly as X ₁ and X ₂ in the alkyl group - one or not adjacent two or more -CH ₂ except groups - group, It may be replaced by the following formula.

[Chemical 136]

Further, preferable examples of R ₅ 'and R ₆ ' include the following. i) a straight-chain alkyl group having 1 to 15 carbon atoms

[Chemical 137] p: an integer of 0 to 5, q: an integer of 2 to 11 may be optically active.

[Chemical 138] r: integer of 0 to 6, s: 0 or 1, t: 1 to 1
Integer of 4 Optically active.

[0109]

[Chemical 139] w: integer of 1 to 15 may be optically active.

[0110]

[Chemical 140] A: integer of 0 to 2; B: integer of 1 to 15 It may be optically active.

[Chemical 141] C: integer of 0 to 2, D: integer of 1 to 15 may be optically active.

When the optically active compound of the present invention is mixed with one or more of the above-mentioned liquid crystal compounds or liquid crystal compositions,
The proportion of the optically active compound of the present invention in the liquid crystal composition obtained by mixing is 0.1% by weight to 40% by weight, preferably 0.1% by weight to 20% by weight, more preferably 0.1% by weight.
% To 10% by weight. When two or more optically active compounds of the present invention are used, the ratio of the mixture of two or more optically active compounds of the present invention in the liquid crystal composition obtained by mixing is 0.1% by weight to 40%. % By weight, preferably 0.
1% to 20% by weight, more preferably 0.1% by weight
It is set to 10% by weight.

Further, the ferroelectric liquid crystal layer in the ferroelectric liquid crystal element according to 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 preferably prepared by sealing in a device cell and then gradually cooling to form a liquid crystal layer and returning to normal pressure. FIG. 1 is a schematic sectional view showing an example of a liquid crystal element having a ferroelectric liquid crystal layer of the present invention for the purpose of 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 a light source. The two glass substrates 2 are covered with transparent electrodes 3 each made of a thin film of In ₂ O ₃ , SnO ₂ or ITO (Indium Tin Oxide). 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.

The insulating orientation control layer 4 in the liquid crystal device of the present invention is, for example, silicon nitride, silicon carbide containing hydrogen, silicon oxide, boron nitride, boron nitride containing hydrogen, cerium oxide, Aluminum oxide, zirconium oxide, titanium oxide or an inorganic material insulating layer such as magnesium fluoride is formed, and further polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylene, polyester,
An organic insulating material such as polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin or photoresist resin is used as the orientation control layer. The insulating orientation control layer 4 may have a two-layer structure, and may be a single layer of an inorganic material insulating orientation control layer or an organic material insulating orientation control layer.

When the insulating alignment control layer 4 in the liquid crystal device of the present invention is made of an inorganic insulating substance, it can be formed by a vapor deposition method, and when an organic insulating substance is used, the organic insulating substance is dissolved. Solution or its precursor solution (0.1 to 20% by weight, preferably 0.2 to 10% by weight in the solvent)
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 then cured under predetermined curing conditions (for example, under heating) to form a film. At this time, the insulating orientation control layer 4
The layer thickness is usually 10Å to 1 μm, preferably 10Å to 30
00Å, more preferably 10Å to 1000Å are suitable.

The two glass substrates 2 that have been subjected to the above treatment can be kept at an arbitrary interval by the spacers 5, and for example, silica beads or alumina beads having a predetermined diameter can be sandwiched between the two glass substrates 2 as spacers. However, there is a method of sealing the periphery with a sealing material, for example, an epoxy adhesive. Alternatively, a polymer film or glass fiber may be used as a spacer. Ferroelectric liquid crystal is enclosed between the two glass substrates thus formed.

The thickness of the ferroelectric liquid crystal layer 1 in which the ferroelectric liquid crystal is enclosed is generally 0.5 to 20 μm, preferably 1
~ 5 μm. Also, it is connected to an external power source 7 by a lead wire connected from the transparent electrode 3. Glass substrate 2
A polarizing plate 8 is attached to the outside of the. Since the liquid crystal element shown in FIG. 1 is a transmissive type, a light source 9 is provided.

FIG. 2 schematically shows an example of a cell for explaining the operation of the ferroelectric liquid crystal element. 21a and 2
1b is In ₂ O ₃ , SnO ₂ or ITO (Indium-Tin), respectively.
Oxide) is a substrate (glass plate) covered with a transparent electrode composed of a thin film. A liquid crystal of SmC ^* phase or SmH ^* phase, which is oriented so that the liquid crystal molecular layer 22 is perpendicular to the glass surface of the substrate 2, is enclosed between the substrates 21a and 21b. 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. Here, when a voltage of a certain threshold value or more 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 moments (P⊥) 24 are all oriented in the electric field direction. 23 can change the orientation 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 Nicol polarizers are placed above and below the glass surface, a voltage is applied. It is easy to understand that the liquid crystal optical modulation element has optical characteristics that change depending on the polarity.

The liquid crystal cell preferably used in the optical modulator of the present invention has a sufficiently thin thickness (for example,
10 μm or less). As a result, as the liquid crystal layer becomes thinner, the helical structure of the liquid crystal molecules unwinds as shown in FIG. 3, and the dipole moment Pa or Pb of the liquid crystal molecule is upward (34a) or downward (34b). Take either state. When electric fields Ea or Eb having different polarities which are equal to or more than a certain threshold value are applied to such a cell by the voltage applying means 31a and 31b, the dipole moment corresponds to the electric field vector of the electric fields Ea or Eb. And the liquid crystal molecules are oriented to either the first stable state 33a or the second stable state 33b.

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. The second point will be further described 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. When a reverse electric field Eb is applied, the liquid crystal molecules are oriented in the second stable state 33b and change their orientation, but they remain in this state even when the electric field is cut off. Also, the applied electric field E
As long as a or Eb does not exceed a certain threshold value, the previous orientation state is still maintained. The liquid crystal device of the present invention is used in a display panel unit, and a data format and SY which are image information having scanning line address information shown in FIGS.
The liquid crystal display device of the present invention is realized by using the communication synchronizing means based on the NC signal.

The image information is generated by the graphics controller 102 on the main body side and transferred to the display panel 103 according to the signal transfer means shown in FIGS. The graphics controller 102 is a CPU
(Central processing unit, hereinafter abbreviated as GCPU 112) and VRAM (memory for storing image information) 114 are in charge of managing and communicating image information between the host CPU 113 and the liquid crystal display device 101, and control method of the present invention. Are mainly implemented on the graphics controller 102. A light source is arranged on the back surface of the display panel.

[0121]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. The present invention is not limited to these examples.

Example 1 Synthesis of Exemplified Compound I-78

[Chemical 142]

In a 30 ml eggplant flask, 0.30 g of optically active 2-hexylmalan-5-carboxylic acid (A)
(1.21 mmol), 4- (5-decylpyrimidine-
2-yl) phenol 0.38 g (1.22 mmmo
l) and 9 ml of dichloromethane were added and dissolved, and 0.25 g (1.21 mmol) of N, N′-dicyclohexylcarbodiimide and 0.03 g of 4-dimethylaminopyridine were sequentially added while stirring at room temperature, and the mixture was stirred at room temperature for 6 hours. Then, it was left at room temperature overnight. The precipitated N, N'-dicyclohexylurea was filtered off, and the filtrate was dried under reduced pressure. The residue was purified by silica gel column chromatography (eluent: toluene / ethyl acetate: 100/1), recrystallized with a mixed solvent of toluene-methanol, and further recrystallized with acetone to give an optically active 2
-Hexylmalan-5-carboxylic acid-4- (5-decylpyrimidin-2-yl) phenyl ester (I-7
8) 0.51 g (yield 77.8%) was obtained.

The phase transition temperature of this compound is shown below.

Example 2 Synthesis of Exemplified Compound I-5

[Chemical 143]

0.30 g (1.21 mmol) of optically active 2-hexylmalan-5-carboxylic acid (A) and 0.27 g (1.21 mmo) of 4-octyloxyphenol.
1) was used in the same manner as in Example 1 to obtain optically active 2-hexylmalan-5-carboxylic acid-4-octyloxyphenyl ester (I-5) (0.38 g, yield: 69.4).
%) Was obtained.

The phase transition temperature of this compound is shown below.

Example 3 Liquid crystal composition A was prepared by mixing the following compounds including the exemplified compound I-78 prepared in Example 1 in the following parts by weight.

[0129]

[Chemical 144]

[0130]

[Chemical 145]

This composition A exhibits the following phase transition temperature.

Example 4 Two 0.7 mm thick glass plates were prepared, an ITO film was formed on each of the glass plates, voltage application electrodes were prepared, and SiO ₂ was vapor-deposited on this to form an insulating layer. did. Further, a silane coupling agent [Shin-Etsu Chemical Co., Ltd .: K
BM-602] in 0.2% isopropyl alcohol at a rotation speed of 2,000 rpm. Was applied for 15 seconds with a spinner of No. 1 and surface-treated. After that, a heat drying treatment was performed at 120 ° C. for 20 minutes.

Next, a polyimide resin precursor [manufactured by Toray Industries, Inc .: SP
-510] in a 1.5% dimethylacetamide solution at a rotation speed of 2,000 rpm. Was applied for 15 seconds using the spinner of After the film formation, a heat condensation baking treatment was performed at 300 ° C. for 60 minutes. At this time, the film thickness of the polyimide coating film was about 250Å.

Further, the fired coating was rubbed with an acetate flocked cloth, washed with an isopropyl alcohol solution, and silica beads having an average particle diameter of 2 μm were dispersed on one of the glass plates, and then rubbed. The axes were made parallel to each other, and glass plates were attached 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 A mixed in Example 3 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 obtain the ferroelectric liquid crystal device of this example. It was created. When the cell thickness of this cell was measured with a Berek phase plate, it was about 2 μm.

[0135] Using the ferroelectric liquid crystal device of this example,
Magnitude of polarization P_sAnd Peak To Woo peak voltage V_pp
= 20V voltage applied, the optical
Detect a response (change in transmitted light amount 0 to 90%),
Response speed at 30 ℃ and 40 ℃ (hereinafter optical response speed
I said).

[0136] The measurement results are shown below. ^{20 ℃ 30 ℃ 40 ℃ Response speed 193μsec 123μsec 82μsec} P _s 9.1 nC / cm ² 7.5 nC / cm ² 5.4 nC / cm ²

Example 5 The following compounds were mixed in the following parts by weight to prepare a liquid crystal composition B.
It was created.

[0138]

[Chemical 146]

Further, for this liquid crystal composition B, the optically active 2-hexylmalan-5-carboxylic acid-4- (5-decylpyrimidin-2-yl) phenyl ester prepared in Example 1 (exemplified compound) was used. I-78), liquid crystal composition B: exemplary compound I-78 = 99 wt%: 1.0 wt%
The liquid crystal composition C was prepared by mixing the above components.

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 4 except that these liquid crystal compositions B and C were used, and the respective orientations were observed. The cholesteric pitch was measured by the Kano's wedge method. The results are shown below.

[0141]

[Table 1] From the above results, it can be seen that the optically active compound of the present invention is effective in controlling the cholesteric pitch, and the liquid crystal composition of the present invention has excellent alignment properties.

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

[0143]

[Chemical 147]

[0144]

[Chemical 148]

Further, the following exemplary compounds were mixed with the liquid crystal composition D in the following parts by weight to prepare a liquid crystal composition E of this example.

[0146]

[Chemical 149]

Next, a ferroelectric liquid crystal device was prepared in exactly the same manner as in Example 4 except that the liquid crystal composition E was injected into the cell, and the optical response speeds at 10 ° C., 25 ° C. and 40 ° C. were measured. did. The uniform alignment in the liquid crystal device using the liquid crystal composition E of this example was good, and a monodomain state was obtained. The measurement results are shown below. 10 ° C. 25 ° C. 40 ° C. Response speed 545 μsec 272 μsec 153 μsec Further , when the switching state was observed, a clear switching operation was observed during driving, and the bistability when the voltage application was stopped was also good.

Comparative Example 1 A ferroelectric liquid crystal device was prepared in the same manner as in Example 4 except that the liquid crystal composition D mixed in Example 6 was injected into the cell, and the liquid crystal composition was manufactured at 10 ° C., 25 ° C. and 40 ° C. The optical response speed in was measured. The measurement results of the optical response speed are shown below. 10 ° C 25 ° C 40 ° C Response speed 784 μsec 373 μsec 197 μsec

Example 7 Instead of the liquid crystal compositions I-12, I-33 and I-84 used in Example 6, the following exemplified compounds were mixed in the respective parts by weight shown below to prepare the compound of this example. A liquid crystal composition F was prepared.

[0150]

[Chemical 150]

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 4 except that the liquid crystal composition F obtained as described above was used, and the liquid crystal composition was prepared at 10 ° C., 25 ° C. and 40 ° C. When the optical response speed was measured and the switching state and the like were observed, uniform alignment in the liquid crystal element was good, and a monodomain state was obtained. The measurement results are shown below. 10 ℃ 25 ℃ 40 ℃ Response speed 522μsec 256μsec 146μsec

Example 8 Exemplified compounds I-3, I-26 and I used in Example 7
Instead of -66, the following exemplary compounds were mixed in the respective weight parts shown below to prepare a liquid crystal composition G of this example.

[0153]

[Chemical 151]

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 4 except that the liquid crystal composition G was used.
Measuring the optical response speed at ℃, 25 ℃ and 40 ℃,
When the switching state and the like were observed, uniform alignment in the 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 567 μsec 280 μsec 155 μsec

Example 9 The following compounds were mixed in the following parts by weight to prepare a liquid crystal composition H.
It was created.

[0156]

[Chemical 152]

[0157]

[Chemical 153]

[0158]

[Chemical 154]

Further, the following exemplary compounds were mixed with the liquid crystal composition H in the following parts by weight to prepare a liquid crystal composition J of this example.

[0160]

[Chemical 155]

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 4 except that the liquid crystal composition J was used.
Measuring the optical response speed at ℃, 25 ℃ and 40 ℃,
When the switching state and the like were observed, uniform alignment in the 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 508 μsec 266 μsec 147 μsec

Comparative Example 2 A ferroelectric liquid crystal device was prepared in exactly the same manner as in Example 4 except that the liquid crystal composition H mixed in Example 9 was injected into the cell, and the ferroelectric liquid crystal device was manufactured at 10 ° C., 25 ° C. and 40 ° C. The optical response speed in was measured. The results are shown below. 10 ° C 25 ° C 40 ° C Response speed 668 μsec 340 μsec 182 μsec

Example 10 Exemplified Compounds I-8, I-31 and I used in Example 9
In place of -52, the following exemplary compounds were mixed in the respective weight parts shown below to prepare a liquid crystal composition K of this example.

[0164]

[Chemical 156]

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 4 except that the liquid crystal composition K was used.
Measuring the optical response speed at ℃, 25 ℃ and 40 ℃,
When the switching state and the like were observed, uniform alignment in the liquid crystal element was good, and a monodomain state was obtained.
The measurement results are shown below. 10 ℃ 25 ℃ 40 ℃ Response speed 536μsec 275μsec 155μsec

Example 11 In place of Exemplified Compounds I-16, I-40 and I-104 used in Example 10, the following example compounds were mixed in the respective parts by weight shown below to prepare a liquid crystal composition of this example. Item L was created.

[0167]

[Chemical 157]

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 4 except that the liquid crystal composition L was used.
Measuring the optical response speed at ℃, 25 ℃ and 40 ℃,
When the switching state and the like were observed, uniform alignment in the 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 491μsec 255μsec 139μsec

As is clear from the results of Examples 6 to 11, the liquid crystal compositions E, F, G, J, K and L of the present invention containing the optically active compound represented by the general formula (I) are contained. The ferroelectric liquid crystal device has improved operating characteristics at low temperatures and high-speed response, and also has reduced temperature dependence of response speed.

Example 12 An example except that a 2% aqueous solution of polyvinyl alcohol resin (PUA-117 manufactured by Kuraray Co., Ltd.) was used in place of the 1.5% dimethylacetamide solution of the polyimide resin precursor used in Example 8. Exactly the same method as in 4, 10 ° C, 2
The optical response speed at 5 ° C. and 40 ° C. was measured. The results are shown below. 10 ° C 25 ° C 40 ° C Response speed 557μsec 274μsec 157μsec

Example 13 Except that the SiO ₂ used in Example 8 was not used and an alignment control film was formed only with a polyimide resin, the same method as in Example 4 was performed at 10 ° C., 25 ° C. and 40 ° C. The optical response speed was measured. The measurement results are shown below. 10 ℃ 25 ℃ 40 ℃ Response speed 546μsec 271μsec 150μsec

As is apparent from Examples 12 and 13, even when the element structure was changed, the element containing the ferroelectric liquid crystal composition according to the present invention had a very low temperature operating characteristic as in Example 8. It is improved and the temperature dependence of the response speed is reduced.

[0173]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a novel optically active compound can be provided. Further, such an optically active compound of the present invention can be effectively applied to a liquid crystal device utilizing ferroelectricity if it exhibits a chiral smectic phase by itself. Further, when the liquid crystal composition partially containing the optically active compound of the present invention exhibits a chiral smectic phase, a liquid crystal element containing the liquid crystal composition utilizes the ferroelectricity exhibited by the liquid crystal composition. It can be operated. The ferroelectric liquid crystal element of the present invention that can be used in this manner has good switching characteristics, improved low-temperature operability, and can reduce temperature dependence of response speed. Further, by controlling the helical pitch of the cholesteric phase using the optically active compound of the present invention, uniform orientation can be obtained. It should be noted that a display device in which the liquid crystal element is used as a display element in the present invention and is combined with a light source and a drive circuit 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 a block diagram showing a liquid crystal display device having a liquid crystal element utilizing ferroelectricity and a graphics controller.

FIG. 5 is a timing chart of image information communication between the liquid crystal display device and the graphics controller.

[Explanation of symbols]

 1 Liquid crystal layer having a 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 Io Incident light I Transmitted light 21a Substrate 21b Substrate 22 Having chiral smectic phase Liquid crystal 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 Graphics 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 (72) Inventor Shinichi Nakamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yoko Yamada 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Ikuro Nakazawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (34)

[Claims] 1. A compound represented by the following general formula (I):
And an optically active compound. [Chemical 1](In the formula, R ₁And R ₂Is a hydrogen atom, halogen, CN, orAlternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
The hydrogen atom may be exchanged for a fluorine atom. X ₁
And X ₂Is a single bond, -COO-, -OOC-, -CH₂
O-, -OCH₂-, -CH ₂CH ₂-Or-C≡C-
Show, A ₁, A ₂And A ₃Are single bonds, or
Indicates either. [Chemical 3]R ₃, R _Four, R _FiveAnd R ₆Is the number of hydrogen atoms or carbon atoms, respectively
Represents a linear or branched alkyl group of 1 to 18. Y
₁And Y₂Is H, F, Cl, Br, CH ₃, CF ₃Or
Indicates CN. Z represents O or S. However, A ₁, A ₂Over
And A ₃At least one of the following formulas
Therefore, the other two do not become a single bond at the same time. [Chemical 4]Also, -A ₁-X ₁-A ₂-X ₂-A ₃− Is,Then X₁And X₂Is -COO- or -CH₂O-
There is no. Also, -A₁-X₁-A₂-X₂-A₃− Is,Then X₁And X₂Is -OOC- or -OCH_Two-In
There is no. Also, A₁Or-A₁-X₁-A₂− Is the following formula
In the case of R₁And R_FiveAre different from each other, andA₃Or A₂-X₂-A₃Where R is₂And R₆Are mutual
Very different. [Chemical 8]In addition, * shows that it is optically active. ) 2. The optically active compound represented by formula (I) is any one of the following (Ia) to (Iu):
The optically active compound according to item 1. [Chemical 9] [Chemical 10] [Chemical 11] [Chemical 12] (In the formula, R ₁ and R ₂ are a hydrogen atom, halogen, CN, or Alternatively, it is a linear or branched alkyl group having 1 to 18 carbon atoms, and one or two or more non-adjacent methylene groups in the alkyl group are -O-, -S-, -CO-. ,
-COO-, -OOC-, -CH = CH-, -C≡C-
And a hydrogen atom in the alkyl group may be replaced by a fluorine atom. X ₁ and X ₂ are a single bond, -COO -, - OOC -, - CH 2 O
_{-, - OCH 2 -, -} CH 2 CH 2 - or -C≡C- indicates, A ₁ represents one of the following formulas. [Chemical 14] A ₂ and A ₃ are respectively A ₁ or Indicates. R ₃ , R ₄ , R ₅ and R ₆ each represent a hydrogen atom or a linear or branched alkyl group having 1 to 18 carbon atoms. Y ₁ and Y ₂ are H, F, Cl, Br, CH ₃ , C
Indicates F ₃ or CN. Z represents O or S. However, R ₁ and R ₅ are different from each other, and R ₂ and R ₆ are also different from each other. still,*
Indicates that it is optically active. ) 3. The optically active compound according to claim 1, wherein the optically active compound represented by the general formula (I) is one of the following (Iv) or (Iw). [Chemical 16] (In the formula, R ₁ and R ₂ are a hydrogen atom, halogen, CN, or Alternatively, it is a linear or branched alkyl group having 1 to 18 carbon atoms, and one or two or more non-adjacent methylene groups in the alkyl group are -O-, -S-, -CO-. ,
-COO-, -OOC-, -CH = CH-, -C≡C-
The hydrogen atom in the alkyl group may be replaced with a fluorine atom. X ₂
It represents a single _{bond, -OOC -, - OCH 2 -} , - CH 2 CH 2
-Or-C≡C- is shown, and X ₁ is X ₂ , -COO-, or -CH ₂ O-. R ₆ represents a hydrogen atom or a linear or branched alkyl group having 1 to 18 carbon atoms. Y
₁ and Y ₂ are H, F, Cl, Br, CH ₃ , CF ₃ or C
Represents N. However, R ₂ and R ₆ are different from each other, and * means that it is optically active. ) 4. An optically active compound represented by formula (I)
Is any of (Iaa) to (Iud).
The optically active compound described. [Chemical 18][Chemical 19][Chemical 20][Chemical 21][Chemical formula 22][Chemical formula 23][Chemical formula 24][Chemical 25][Chemical formula 26][Chemical 27][Chemical 28][Chemical 29](In the formula, R ₁And R ₂Is a hydrogen atom, halogen, CN, orAlternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
Hydrogen atoms may be exchanged for fluorine atoms. R _FiveOver
And R ₆Are each a hydrogen atom or a straight chain having 1 to 18 carbon atoms.
A branched or branched alkyl group. Y₁And Y₂Is H,
F, Cl, Br, CH ₃, CF ₃Or CN. However,
R ₁And R _FiveIs different from ₂And R ₆Are also different from each other.
In addition, * shows that it is optically active. ) 5. An optically active compound represented by formula (I)
Is (Ian) or (Ibf).
Optically active compound. [Chemical 31](In the formula, R ₁And R ₂Is a hydrogen atom, halogen, CN, orAlternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
Hydrogen atoms may be exchanged for fluorine atoms. R
₆Is a hydrogen atom or a straight chain having 1 to 18 carbon atoms or
Is a branched alkyl group. Y₁And Y₂Is H, F,
Cl, Br, CH ₃, CF ₃Or CN. However, R ₂
And R ₆Is different from, and * indicates that it is optically active.
You ) 6. An optically active compound represented by formula (I)
Is any of (Iva) to (Iwg).
The optically active compound according to item 1. [Chemical 33][Chemical 34](In the formula, R ₁And R ₂Is a hydrogen atom, halogen, CN, orAlternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
Hydrogen atoms may be exchanged for fluorine atoms. R
₆Is a hydrogen atom or a linear or branched chain having 1 to 18 carbon atoms.
It is a branched alkyl group. Y₁And Y₂Is H, F, C
l, Br, CH ₃, CF ₃Or CN. However, R ₂When
R ₆Is different from, and * indicates that it is optically active.
You ) 7. An optically active compound represented by formula (I)
Is the following formula (I) '. Optically activated according to claim 1.
Compound [Chemical 36](In the formula, R ₁And R ₂Is a hydrogen atom, halogen, CN, orAlternatively, a straight-chain or branched alkyl group having 1 to 18 carbon atoms
Is an alkyl group and is not adjacent to one of the alkyl groups
Two or more methylene groups are -O-, -S-, -CO-,
-COO-, -OOC-, -CH = CH-, -C≡C-
In the alkyl group
The hydrogen atom may be exchanged for a fluorine atom. X ₁
Is a single bond, -COO-, -OOC-, -CH₂O-,
-OCH₂-, -CH ₂CH ₂-Or -C≡C- is shown,
A ₁Is one of the following formulas:A₂Is a single bond or A₁Is. R ₃, R _FourAnd R ₆Respectively
Straight or branched chain having 1 to 18 hydrogen atoms or carbon atoms
Is an alkyl group. Y₁And Y₂Is H, F, Cl, B
r, CH ₃, CF ₃Or CN. Z represents O or S
You However, R₂And R₆Are different from each other, * is optically active
Indicates that ) 8. The optically active compound according to claim _1, wherein R ₁ and R ₂ in the general formula (I) are any of the following (i) to (vii). [Chemical Formula 39] (However, a is an integer of 1 to 17, d, g and i
Is an integer of 0 to 7, b, e and h are integers of 1 to 8, f and k are 0 or 1, j is an integer of 1 to 15, X ₃ is a single bond, —O— , -OOC- or -COO-
Indicates. ) 9. Formulas (Ia) to (Iu) and (Iv) to
R in (Iw) _FiveAnd R ₆Is a hydrogen atom, or
The optically active compound according to claim 3. 10. A liquid crystal composition comprising at least one kind of the optically active compound according to claim 1. 11. The liquid crystal composition according to claim 10, wherein the optically active compound is contained in an amount of 0.1 to 60% by weight based on the liquid crystal composition. 12. The liquid crystal composition according to claim 10, wherein the optically active compound is contained in an amount of 0.1 to 40% by weight based on the liquid crystal composition. 13. The liquid crystal composition according to claim 10, wherein the optically active compound is contained in an amount of 0.1 to 20% by weight with respect to the liquid crystal composition. 14. The liquid crystal composition according to claim 10, which has a chiral smectic phase. 15. A liquid crystal device comprising the liquid crystal composition according to claim 10 disposed between a pair of electrode substrates. 16. The liquid crystal device according to claim 15, further comprising an alignment control layer provided on the electrode substrate. 17. The liquid crystal device according to claim 16, wherein the alignment control layer is a layer that has been subjected to a rubbing treatment. 18. The liquid crystal device according to claim 15, wherein the pair of electrode substrates are arranged with a film thickness in which the spiral formed by the alignment of the liquid crystal molecules is released. 19. A display device comprising the liquid crystal element according to claim 15. Description: 20. The display device according to claim 19, further comprising a drive circuit for the liquid crystal element. 21. The display device according to claim 19, further comprising a light source. 22. A liquid crystal composition comprising at least one kind of the optically active compound according to claim 1, and one or more kinds of other optically active compounds and a non-chiral compound. 23. The liquid crystal composition according to claim 22, wherein the optically active compound according to claim 1 is contained in an amount of 0.1 to 40% by weight based on the liquid crystal composition. 24. The liquid crystal composition according to claim 22, wherein the optically active compound according to claim 1 is contained in an amount of 0.1 to 20% by weight based on the liquid crystal composition. 25. The liquid crystal composition according to claim 22, wherein the optically active compound according to claim 1 is contained in an amount of 0.1 to 10% by weight based on the liquid crystal composition. 26. The liquid crystal composition according to claim 22, which has a chiral smectic phase. 27. A liquid crystal device comprising the liquid crystal composition according to claim 22 disposed between a pair of electrode substrates. 28. The liquid crystal device according to claim 27, further comprising an alignment control layer provided on the electrode substrate. 29. The liquid crystal device according to claim 28, wherein the orientation control layer is a layer which has been subjected to a rubbing treatment. 30. The liquid crystal device according to claim 27, wherein the pair of electrode substrates are arranged with a film thickness in which the spiral formed by the alignment of liquid crystal molecules is released. 31. A display device comprising the liquid crystal element according to claim 27. 32. The display device according to claim 31, further comprising a drive circuit for the liquid crystal element. 33. The display device according to claim 31, further comprising a light source. 34. A display method using the liquid crystal composition according to claim 10.