JPH07101894A - Optically active compound, liquid crystal composition containing the same, liquid crystal element using the same, indicating method and indicating device therefor - Google Patents

Abstract

PURPOSE:To obtain the subject new compound useful as a display device, etc., readily orientating by simple rubbing treatment, showing uniform monodomain orientation free from defect, having excellent switching characteristics. CONSTITUTION:A compound of formula I [R1 and R2 are 1-18C (branched) alkyl; X1 is single bond, O, COO, OOC or CO; X2 is COO or CH2O; A1, A2 and A3 are (mono- or dihalogen-substituted) 1,4phenylene, 1,4-cyclohexylene or 2,5-pyrimidinylene; (m) and (n) are 0 or 1; * is optically activel such as 4'-decyloxy-biphenylcarboxylic acid 4'-(1-trifluoromethylheptyl)phenyl. The compound of formula I, in the case of X2 being COO, is obtained by reacting a compound of formula II with a compound of formula III or, in the case of X2 being CH2O, by reacting the compound of formula II with a compound of formula IV.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel optically active compound, a liquid crystal composition containing the same, a liquid crystal device using the liquid crystal composition, a method for displaying the same, and a display device using the liquid crystal device for display. It is about.

[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"
("Applied Physics Letter
s ") Vo.18, No.4 (1971.2.15)
P. 127-128 "Voltage Depend"
ent Optical Activity of a
Twisted Nematic Liquid Cr
TN (Twisted Nem)
atic) type liquid 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 display, the simple matrix drive is the most effective in consideration of price, productivity and the like. The simple matrix method employs an electrode configuration in which a scan electrode group and a signal electrode group are arranged in a matrix, and in order to drive the scan electrode group, 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.

However, when 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 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 works normally,
When the number of scanning lines (N) is increased, the whole screen (1
The time (duty ratio) in which an effective electric field is applied to one selection point during scanning of a frame decreases at a rate of 1 / N.

For this reason, the voltage difference as the effective value applied to the selected point and the non-selected point in the case of repeating scanning is
As the number of scanning lines increases, the number becomes smaller, and as a result, deterioration of image contrast and crosstalk are inevitable drawbacks.

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 an essentially unavoidable problem that occurs when driving (that is, repeatedly scanning) using the temporal accumulation effect.

In order to improve this point, the voltage averaging method, 2
The frequency drive 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 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 Lagerwell.
11) (Japanese Patent Laid-Open No. 56-10721).
6 gazette, US Pat. No. 4,367,924, etc.). Ferroelectric liquid crystals having a chiral smectic C phase (SmC ^* phase) or H phase (SmH ^* phase) are generally used as the bistable liquid crystal.

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, and therefore the optical modulation used in the above-mentioned TN type liquid crystal. Unlike the element, for example, the liquid crystal is oriented in the first optically stable state with respect to one electric field vector, and the liquid crystal is oriented in the second optically stable state with respect to the other electric field vector. Further, this type of liquid crystal has a property (bistability) of taking one of the 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, high-density, large-screen displays. For this reason, research has been conducted extensively on liquid crystal materials with ferroelectricity, but the ferroelectric liquid crystal materials developed to date have sufficient characteristics for use in liquid crystal elements, including low-temperature operating characteristics and high-speed response characteristics. It is hard to say that it has.

Between the response time τ, the magnitude Ps of spontaneous polarization and the viscosity η, the following equation [II]

[0015]

[Equation 1] (However, E is the applied electric field.)

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 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, the response speed may not be so fast.

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

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 having a small temperature dependence of the response speed is required. Required.

Furthermore, in order to realize a display device having excellent image quality, the alignment characteristics of the liquid crystal material used are also important issues. For example, a liquid crystal material exhibiting the SmC ^* phase has a zigzag defect or a gap retaining material (for example, a gap maintaining material in a liquid crystal cell).
The feature is that alignment defects are likely to occur around the spacer beads.

Furthermore, alignment defects easily occur due to the difference in the rubbing state of the alignment film caused by the unevenness of the alignment film surface derived from the constituent elements of the liquid crystal element. In many cases, the SmC ^* phase state is a phase state in which an isotropic phase state passes through some phase transitions, and is also a state closer to a crystalline phase than a nematic phase. Therefore, the present inventors speculate.

What is a serious problem is that these alignment defects lower the bistability characteristic of the SmC ^* liquid crystal material, and further lower the image quality, lower the contrast, and increase the crosstalk. Will be a factor that causes.

[0023]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the liquid crystal device as described above, and provides a ferroelectric liquid crystal device which is expected to be applied to a high-speed optical shirt, a high density display and a large screen display. As can be realized, by a simple rubbing treatment, the liquid crystal composition is easily aligned, exhibits uniform monodomain alignment without defects, and has a high response speed.
In particular, it is an object of the present invention to provide a liquid crystal composition exhibiting a ferroelectric chiral smectic phase, a liquid crystal element using the liquid crystal composition, a display method and a display device using the same.

[0024]

That is, the present invention provides the following general formula (I):

[0025]

[Chemical 13]

(In the formula, R ₁ and R ₂ are each 1 to 1 carbon atoms.
18 straight-chain or branched alkyl groups are shown. X ₁
Is a single bond, -O-, -COO-, -OOC-, -CO.
- indicates, _{X 2} is -COO -, - shows a _CH 2 O-.
A ₁ , A ₂ , and A ₃ are

[0027]

[Chemical 14] Indicates. Y ₁ and Y ₂ represent H or a halogen atom. m and n are 0 or 1. * Indicates that it is optically active. )

An optically active compound represented by the formula (1), a liquid crystal composition containing at least one of the optically active compounds, and the liquid crystal composition disposed between a pair of electrode substrates. The present invention provides a liquid crystal element, a display method thereof, and a display device.

Further, among the optically active compounds represented by the above general formula (I), a particularly preferable compound is (Ia)
(If) are mentioned.

[0030]

[Chemical 15]

(In the formula, R ₁ and R ₂ are each a carbon atom number of 1 to 1.
18 straight-chain or branched alkyl groups are shown. X ₁
Is a single bond, -O-, -COO-, -OOC-, -CO.
- indicates, _{X 2} is -COO -, - shows a _CH 2 O-.
Y ₁ and Y ₂ represent H or a halogen atom. * Indicates that it is optically active. ) You. )

Further, among the optically active compounds represented by the general formula (I), more preferred compounds are (Ia
a) to (Ifa).

[0033]

[Chemical 16]

[0034]

[Chemical 17]

(In the formula, R ₁ and R ₂ are each a carbon atom number of 1 to 1.
18 straight-chain or branched alkyl groups are shown. * Indicates that it is optically active. )

Further, R ₁ preferably has 3 carbon atoms.
Is a straight-chain alkyl group having 12 to 12, and R ₂ is preferably a straight-chain alkyl group having 1 to 14 carbon atoms.

Next, a general method for synthesizing the optically active compound represented by the general formula (I) will be shown.

[0038]

[Chemical 18]

[0039]

[Chemical 19]

The optically active compound represented by formula (I) is preferably applied by the present applicant (Japanese Patent Application No.
The following general formula (I
It is prepared from the optically active 4- (1-trifluoromethylalkyl) phenol of II).

[0041]

[Chemical 20] (In the formula, R ₂ represents a linear or branched alkyl group having 1 to 18 carbon atoms. * Represents optically active.)

Next, specific examples of the optically active compound represented by the general formula (I) will be shown below.

[0043]

[Chemical 21]

[0044]

[Chemical formula 22]

[0045]

[Chemical formula 23]

[0046]

[Chemical formula 24]

[0047]

[Chemical 25]

[0048]

[Chemical formula 26]

[0049]

[Chemical 27]

[0050]

[Chemical 28]

[0051]

[Chemical 29]

[0052]

[Chemical 30]

[0053]

[Chemical 31]

[0054]

[Chemical 32]

[0055]

[Chemical 33]

[0056]

[Chemical 34]

[0057]

[Chemical 35]

[0058]

[Chemical 36]

The liquid crystal composition of the present invention can be obtained by mixing at least one kind of the optically active compound represented by the general formula (I) and one or more kinds of other liquid crystal compounds 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.

Other liquid crystal compounds used in the present invention are represented by the following general formulas (III) to (XIII).

[0061]

[Chemical 37]

Preferred compounds of the formula (III) are (I
IIa) to (IIIe).

[0063]

[Chemical 38]

[0064]

[Chemical Formula 39]

Preferred compounds of formula (IV) are (IV
a) to (IVc).

[0066]

[Chemical 40]

[0067]

[Chemical 41]

As a preferred compound of the formula (V), (V
a) and (Vb).

[0069]

[Chemical 42]

[0070]

[Chemical 43]

Preferred compounds of the formula (VI) are (VI
a) to (VIf).

[0072]

[Chemical 44]

Here, R ₁ 'and R ₂ ' have 1 to 1 carbon atoms.
8 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 —. Further X _1, X ₂ directly bonded to -CH ₂ - one except group or not adjacent two or more -CH ₂ - groups

[0074]

[Chemical formula 45]

It may be replaced with

However, R ₁ 'or R ₂ ' is one CH ₂ group.

[0077]

[Chemical formula 46]

Or when it is an alkyl halide substituted with -CH halogen-, R ₁ 'or R ₂ ' is not attached to the ring by a single bond.

R ₁ 'and R ₂ ' are preferably i) a straight-chain alkyl group having 1 to 15 carbon atoms.

[0080]

[Chemical 47] p: 0-5 q: 2-11 integer may be optically active.

[0081]

[Chemical 48] r: 0 to 6 s: 0,1 t: 1 to 14 integer may be optically active.

[0082]

[Chemical 49] u: 0, 1 v: 1-16 integer

[0083]

[Chemical 50] w: 1 to 15 integer Optically active

[0084]

[Chemical 51] x: 0 to 2 y: 1 to 15 integer

[0085]

[Chemical 52] z: 1 to 15 integer

[0086]

[Chemical 53] A: 0 to 2 B: 1 to 15 integer Optically active

[0087]

[Chemical 54] C: 0 to 2 D: 1 to 15 integer may be optically active X) H XI) F

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

[0089]

[Chemical 55]

[0090]

[Chemical 56]

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

[0092]

[Chemical 57]

More preferable compounds (Va) to (Vd) include (Vaa) to (Vdf).

[0094]

[Chemical 58]

[0095]

[Chemical 59]

More preferred compounds of (VIa) to (VIf) include (VIaa) to (VIfa).

[0097]

[Chemical 60]

[0098]

[Chemical formula 61]

[0099]

[Chemical formula 62]

More preferred compounds of (VII) include (VIIa) and (VIIb).

[0101]

[Chemical formula 63]

Preferred compounds of the formula (VIII) include (VIIIa) and (VIIIb).

[0103]

[Chemical 64]

More preferable compounds of (VIIIb) include (VIIIba) and (VIIIbb).

[0105]

[Chemical 65]

Here, R ₃ 'and R ₄ ' have 1 to 1 carbon atoms.
8 is a straight-chain or branched alkyl group, wherein one or two or more non-adjacent -CH ₂ groups in the alkyl group-
May be replaced by -CH halogen-. Further X _1, X ₂ directly bonded to -CH ₂ - one except group or not adjacent two or more -CH ₂ - groups

[0107]

[Chemical formula 66]

It may be replaced with.

However, 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 ' is bonded to the ring by a single bond. do not do.

Further, R ₃ 'and R ₄ ' are preferably i) a straight-chain alkyl group having 1 to 15 carbon atoms.

[0111]

[Chemical formula 67] p: 0-5 q: 2-11 integer may be optically active.

[0112]

[Chemical 68] r: 0 to 6 s: 0,1 t: 1 to 14 integer may be optically active.

[0113]

[Chemical 69] u: 0, 1 v: 1-16 integer

[0114]

[Chemical 70] w: 1 to 15 integer Optically active

[0115]

[Chemical 71] A: 0 to 2 B: 1 to 15 integer Optically active

[0116]

[Chemical 72] C: 0 to 2 D: 1 to 15 integer Optically active

[0117]

[Chemical formula 73]

[0118]

[Chemical 74]

[0119]

[Chemical 75]

[0120]

[Chemical 76]

[0121]

[Chemical 77]

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

[0123]

[Chemical 78]

As a preferred compound of the formula (X), (X
a) and (Xb).

[0125]

[Chemical 79]

Preferred compounds of the formula (XII) are (X
IIa) to (XIId).

[0127]

[Chemical 80]

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

[0129]

[Chemical 81]

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

[0131]

[Chemical formula 82]

More preferable compounds of (Xa) and (Xb) are (Xaa) to (Xbb).

[0133]

[Chemical 83]

More preferred compounds of (XI) are (X
Ia) to (XIg).

[0135]

[Chemical 84]

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

[0137]

[Chemical 85]

[0138]

[Chemical 86]

Here, R ₅ 'and R ₆ ' have 1 to 1 carbon atoms.
8 is a straight-chain or branched alkyl group, excluding the —CH ₂ — group directly bonded to X ₁ and X ₂ in the alkyl group 1
Two or more non-adjacent —CH ₂ — groups are

[0140]

[Chemical 87] May be replaced with.

Further, R ₅ 'and R ₆ ' are preferably i) a straight-chain alkyl group having 1 to 15 carbon atoms.

[0142]

[Chemical 88] p: 0-5 q: 2-11 integer may be optically active.

[0143]

[Chemical 89] r: 0 to 6 s: 0,1 t: 1 to 14 integer may be optically active.

[0144]

[Chemical 90] w: 1 to 15 integer Optically active

[0145]

[Chemical Formula 91] A: 0 to 2 B: 1 to 15 integer Optically active

[0146]

[Chemical Formula 92] C: 0 to 2 D: 1 to 15 integer Optically active

When the optically active compound represented by the general formula (I) in the present invention is mixed with one or more kinds of the above-mentioned liquid crystalline compounds or the liquid crystal composition, the liquid crystal composition obtained by the mixing is added. The proportion of the optically active compound represented by formula (I) is preferably 1% by weight to 80% by weight, preferably 1% by weight to 60% by weight, and more preferably 1% by weight to 40% by weight.

When two or more optically active compounds represented by the general formula (I) are used, two or more optically active compounds represented by the general formula (I) in the liquid crystal composition obtained by mixing are used. It is desirable that the proportion of the mixture is 1% by weight to 80% by weight, preferably 1% by weight to 60% by weight.

Next, the liquid crystal element of the present invention comprises the above-mentioned liquid crystal composition disposed between a pair of electrode substrates. Particularly, the ferroelectric liquid crystal layer in the ferroelectric liquid crystal element is as described above. It is preferable to heat the ferroelectric liquid crystal composition prepared in the above to a temperature of an isotropic liquid in a vacuum, to fill it in an element cell, and to cool it gradually to form a liquid crystal layer and return it to normal pressure.

FIG. 1 is a schematic sectional view showing an example of a liquid crystal element having a chiral smectic liquid crystal layer for explaining the structure of a liquid crystal element utilizing ferroelectricity.

Referring to FIG. 1, in the liquid crystal element, a liquid crystal layer 1 exhibiting a chiral smectic phase is arranged between a pair of glass substrates 2 provided with a transparent electrode 3 and an insulating orientation control layer 4, respectively, and the layer is formed. The thickness is set by a spacer 5, and a voltage is applied between a pair of transparent electrodes 3 via a lead wire 6 so that a voltage can be applied from a power supply 7. Also, a pair of substrates 2
Are sandwiched between a pair of crossed Nicol polarizing plates 8, and a light source 9 is arranged outside one of them.

That is, In ₂ O ₃ , SnO ₂ or ITO (Indium Tin Oxide; Indium Tin O ₂₎ is provided on each of the two glass substrates 2.
The transparent electrode 3 made of a thin film such as xide) is covered. An insulating alignment control layer 4 for arranging the liquid crystal in the rubbing direction is formed by rubbing a polymer thin film such as polyimide with gauze or acetate flocking cloth or the like.

As the insulating orientation control layer 4, for example, silicon nitride, silicon nitride containing hydrogen, silicon carbide, silicon carbide containing hydrogen, silicon oxide, boron nitride, boron nitride containing hydrogen. Substance, cerium oxide, aluminum oxide, zirconium oxide, inorganic oxide such as titanium oxide and magnesium fluoride is formed, polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylene, polyester , Polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate,
It may have a two-layer structure in which a layer of an organic insulating material such as polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin or photoresist resin is formed, or an inorganic material insulating orientation control layer or an organic material insulating property. The orientation control layer may be a single layer.

If this insulating orientation control layer is an inorganic type, it can be formed by a vapor deposition method or the like. 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 in a solvent) is used.
% By weight, preferably 0.2 to 10% by weight) and applied by a spinner coating method, a dip coating method, a screen printing method, a spray coating method, a roll coating method, etc. under predetermined curing conditions (for example, under heating). ) And can be formed by curing.

The layer thickness of the insulating orientation control layer 4 is usually 10Å or more.
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 sealing material, for example, an epoxy adhesive material. Other,
A polymer film or glass fiber may be used as the spacer. A liquid crystal exhibiting a chiral smectic phase is enclosed between the two glass substrates. Liquid crystal layer 1
Is generally 0.5 to 20 μm, preferably 1 to 5 μm
Is set to the thickness of.

The transparent electrode 3 is connected to an external power source 7 by a lead wire. Further, on the outer side of the glass substrate 2, a pair of polarizing plates 8 whose polarization axes are, for example, orthogonal crossed Nicols state are attached. The example of FIG. 1 is a transmissive type, and includes a light source 9.

FIG. 2 is a schematic drawing of an example of a cell for explaining the operation of a liquid crystal element utilizing ferroelectricity.
21a and 21b are In ₂ O ₃ and SnO ₂ respectively.
Alternatively, ITO (indium tin oxide; I
a substrate (glass plate) covered with a transparent electrode composed of a thin film such as ndium tin oxide (Sn), in which the liquid crystal molecular layer 22 is oriented so as to be perpendicular to the glass surface.
Liquid crystal of mC ^* phase or SmH ^* phase is enclosed.
A thick line 23 represents a liquid crystal molecule, and this liquid crystal molecule 23 has a dipole moment (P⊥) 24 in a direction orthogonal to the molecule. When a voltage above a certain threshold is applied between the electrodes on the substrates 21a and 21b, the helical structure of the liquid crystal molecules 23 is unraveled, and the dipole moment (P⊥)
The liquid crystal molecules 23 can change the orientation direction so that all 24 are oriented in the electric field direction. The liquid crystal molecule 23 has an elongated shape and exhibits refractive index anisotropy in the major axis direction and the minor axis direction thereof. Therefore, for example, if crossed Nicol polarizers are placed above and below the glass surface, the voltage application polarity is increased. It can be easily understood that the liquid crystal optical modulation element changes its optical characteristics depending on the situation.

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 shown in FIG. 3, as the liquid crystal layer becomes thinner, the helical structure of the liquid crystal molecules unwinds even when no electric field is applied, and the dipole moment Pa or Pb of the liquid crystal molecule is directed upward (34a) or downward (34b). Take either state. When an electric field Ea or Eb having a polarity equal to or higher than a certain threshold is 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 field Ea or Eb. The liquid crystal molecules are turned to the upward stable state 34a or the downward stable direction 34b, and accordingly, the liquid crystal molecules move to the first stable state 3
3a 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 explained with reference to FIG. 3, for example.
When a 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. Further, as long as the applied electric field Ea or Eb does not exceed a certain threshold value, the previous alignment state is still maintained.

By using the liquid crystal element of the present invention in the display panel section and taking the communication synchronizing means by the data format as the image information having the scanning line address information and the SYNC signal shown in FIGS. 4 and 5, a liquid crystal display device is obtained. To realize.

In the figure, the symbols are as follows. 101 ferroelectric liquid crystal display device 102 graphics 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

By using the liquid crystal element of the present invention in the display panel section and taking the communication information synchronizing means by the data format as the image information having the scanning line address information and the SYNC signal shown in FIGS. 4 and 5, a liquid crystal display device is obtained. To realize.

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

[0165]

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 Optically active 4'-decyloxybiphenylcarboxylic acid 4-
Production of (1-trifluoromethylheptyl) phenyl (Exemplary Compound 18)

[0167]

[Chemical formula 93]

Under dry nitrogen, 100 mg (0.282 mmol) of 4'-biphenylcarboxylic acid and 4- (1
-Trifluoromethylheptyl) phenol 69 mg
(0.265 mmol), 4-dimethylaminopyridine 17 mg (0.139 mmol), dicyclohexylcarbodiimide (DCC) 233 mg (1.13 mmo)
l), 3 ml of dry dichloromethane was stirred at room temperature for 12 hours. Ethyl acetate was added thereto, and the mixture was stirred for another 30 minutes, and then crystals were removed by filtration. After distilling off the solvent, thin layer chromatography (hexane / ethyl acetate = 8/1)
Purification was carried out to obtain 98 mg (0.16 mmol) of 4- (1-trifluoromethylheptyl) phenyl optically active 4'-decyloxybiphenylcarboxylic acid.

Yield 62% [α] _D = −16 ° (c 0.93, CHCl 3
₃ ) [α] ₄₃₅ = −34 ° (c 0.93, CHCl 3
₃ )

[0170]

[Equation 2]

Example 2 Two 0.7 mm thick glass plates were prepared, an ITO film was formed on each glass plate, and voltage application electrodes were prepared.
Further, SiO ₂ was vapor-deposited on this to form an insulating layer. Silane coupling agent on glass plate [KB manufactured by Shin-Etsu Chemical Co., Ltd.
M-602] 0.2% isopropyl alcohol solution was rotated at a rotation speed of 2000 r. p. Apply for 15 seconds at m speed,
A surface treatment was applied. After that, a heat drying treatment was performed at 120 ° C. for 20 minutes.

Further, a polyimide resin precursor [Toray Industries, Inc. SP-
510] 1.5% dimethylacetamide solution was rotated at a rotation speed of 2000 r.p.m. p. m spinner for 15 seconds.
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 coating film was about 250Å.

The coating film after firing was subjected to rubbing treatment with an acetate flocked cloth, then washed with an isopropyl alcohol solution, sprayed with alumina beads having an average particle diameter of 2 μm on one glass plate, and then each rubbing treatment. The axes were made parallel to each other, and the glass plates were bonded together using an adhesive sealant [Rixon Bond (Chisso Corporation)], and heated and dried at 100 ° C. for 60 minutes to prepare a cell.

The exemplified compound 18 produced in Example 1 was injected into this cell in an isotropic liquid state, and the temperature was changed from the isotropic phase to 20 ° C./h.
A ferroelectric liquid crystal device was prepared by gradually cooling to 25 ° C. When the cell thickness of this cell was measured with a Berek phase plate, it was about 2 μm.

Using this ferroelectric liquid crystal element, the magnitude Ps of spontaneous polarization and the peak-to-peak voltage Vpp = 10.
By applying a voltage of V, an optical response (change in transmitted light amount: 10% to 90%) under a crossed Nicols was detected, and a response speed (hereinafter referred to as an optical response speed) and a tilt angle were measured. The results are shown in Table 1 below.

[0176]

[Table 1] Measurement temperature Spontaneous polarization Response speed Tilt angle (° C) (nC / cm ² ) (μsec) (°) 55 +0.092 37 8 50 +0.378 56 16 45 +0.444 78 21

Example 3 Liquid Crystal Composition A was prepared by mixing the following compounds in the following parts by weight.

[0178]

[Chemical 94] The phase transition temperature of the liquid crystal composition A is shown.

[0179]

[Equation 3] Further, Exemplified Compound 18 was mixed with Liquid Crystal Composition A in the following parts by weight to prepare Liquid Crystal Composition B.

[0180]

[Chemical 95] It exhibits the following phase transition temperatures:

[0181]

[Equation 4] Next, the optical response speed at 30 ° C. was measured in the same manner as in Example 2 except that the liquid crystal compositions A and B were used. The results are shown below.

[0182]

## EQU00005 ## Liquid Crystal Composition Optical Response Speed (.mu.sec) A 194 B 67

Examples 4 to 8 In place of Exemplified Compound 18 used in Example 3, 5 parts by weight of Exemplified Compound shown below was added to obtain each liquid crystal composition. The optical response speed at 30 ° C. was measured in the same manner as in Example 2 except that this liquid crystal composition was used. The results are shown below.

[0184]

[Table 2]

As is apparent from the results of Examples 4 to 8, the compositions B, C, D, E, F and G containing the optically active compound represented by the general formula (I) of the present invention were used. It can be seen that the optical response speed is faster than that of the composition A containing no.

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

[0187]

[Chemical 96]

[0188]

[Chemical 97]

Further, the following compounds were mixed with the liquid crystal composition H in the weight parts shown below to prepare a liquid crystal composition I.

[0190]

[Chemical 98]

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 2 except that these liquid crystal compositions H and I were used, and the orientation was observed. The results are shown below.

[0192]

## EQU00006 ## Liquid crystal composition Orientation H Many zigzag defects I Uniform monodomain alignment state

Example 10 Liquid crystal composition J was prepared by mixing the following compounds instead of the exemplified compounds 52 and 59 used in Example 9 in the respective parts by weight shown.

[0194]

[Chemical 99]

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 2 except that this liquid crystal composition J was used, and the alignment was observed. As a result, a uniform monodomain alignment state with few zigzag defects was observed. Met.

Example 11 A liquid crystal composition K was prepared by mixing the following compounds instead of the exemplified compounds 52 and 59 used in Example 9 in the respective parts by weight shown.

[0197]

[Chemical 100]

Next, a ferroelectric liquid crystal device was prepared in the same manner as in Example 2 except that this liquid crystal composition K was used, and the alignment was observed. As a result, a uniform monodomain alignment state with few zigzag defects was observed. Met.

As is clear from the results of Examples 9, 10 and 11, the liquid crystal compositions I, J and K of the present invention containing the optically active compound represented by the general formula (I) are compositions not containing them. It can be seen that the liquid crystal composition has less zigzag defects than H and exhibits uniform monodomain alignment, and has good alignment.

[0200]

INDUSTRIAL APPLICABILITY The present invention provides a novel optically active compound. Further, the liquid crystal composition using the optically active compound of the present invention is easily aligned by a simple rubbing treatment,
In addition, a good effect can be obtained in which the orientation showing uniform monodomain orientation without defects is obtained.

Further, the ferroelectric liquid crystal device using the liquid crystal composition of the present invention can be a liquid crystal device having a good switching characteristic and a high response speed. 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 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 Chiral Smectic Phase 2 Glass Substrate 3 Transparent Electrode 4 Insulating Alignment Control Layer 5 Spacer 6 Lead Wire 7 Power Supply 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 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 (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C07C 69/86 69/92 69/94 C07D 239/26 277/84 285/12 C09K 19/10 9279 -4H 19/12 9279-4H 19/20 9279-4H 19/30 9279-4H 19/34 9279-4H 19/42 9279-4H 19/46 9279-4H G02F 1/13 500 9225-2K

Claims (30)

[Claims] 1. An optically active compound represented by the following general formula (I). [Chemical 1] _(Wherein, R 1, _{R 2} is .X ₁ showing a straight-chain or branched alkyl group having 1 to 18 carbon atoms is a single bond,
Represents -O-, -COO-, -OOC-, -CO-, X
₂ -COO -, - shows a _CH 2 O-. A ₁ , A ₂
, A ₃ is Indicates. Y ₁ and Y ₂ represent H or a halogen atom. m and n are 0 or 1. * Indicates that it is optically active. ) 2. The optically active compound according to claim 1, wherein the optically active compound represented by the general formula (I) is any one of the following (Ia) to (If). [Chemical 3] _(Wherein, R 1, _{R 2} is .X ₁ showing a straight-chain or branched alkyl group having 1 to 18 carbon atoms is a single bond,
Represents -O-, -COO-, -OOC-, -CO-, X
₂ -COO -, - shows a _CH 2 O-. Y ₁ , Y ₂
Represents H or a halogen atom. * Indicates that it is optically active. ) You. ) 3. The optically active compound according to claim 1, wherein the optically active compound represented by the general formula (I) is any of the following (Iaa) to (Ifa). [Chemical 4] [Chemical 5] (In the formula, R ₁ and R ₂ represent a linear or branched alkyl group having 1 to 18 carbon atoms. * Represents optically active.) 4. R ₁ in the general formula (I) is a linear alkyl group having 3 to 12 carbon atoms, and R ₂ is a linear alkyl group having 1 to 14 carbon atoms. The optically active compound according to claim 1. 5. A liquid crystal composition comprising at least one kind of the optically active compound according to claim 1. 6. The liquid crystal composition according to claim 5, wherein the optically active compound represented by the general formula (I) is contained in an amount of 1 to 80% by weight based on the liquid crystal composition. 7. The liquid crystal composition according to claim 5, which contains the optically active compound represented by the general formula (I) in an amount of 1 to 60% by weight based on the liquid crystal composition. 8. The liquid crystal composition according to claim 5, wherein the optically active compound represented by formula (I) is contained in an amount of 1 to 40% by weight based on the liquid crystal composition. 9. The liquid crystal composition according to claim 5, wherein the liquid crystal composition has a chiral smectic phase. 10. The liquid crystal composition according to claim 5, wherein the liquid crystal composition has a nematic phase. 11. A liquid crystal device comprising the liquid crystal composition according to claim 5 disposed between a pair of electrode substrates. 12. The liquid crystal device according to claim 11, wherein an alignment control layer is 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 with a film thickness in which a spiral formed by an arrangement of liquid crystal molecules is released. 15. A display device comprising the liquid crystal element according to claim 11. 16. The display is performed by switching the liquid crystal molecules by utilizing the ferroelectricity exhibited by the liquid crystal composition.
Display device described. 17. The display device according to claim 15, further comprising a light source. 18. A display method using a liquid crystal composition containing an optically active compound represented by the following general formula (I). [Chemical 6] _(Wherein, R 1, _{R 2} is .X ₁ showing a straight-chain or branched alkyl group having 1 to 18 carbon atoms is a single bond,
Represents -O-, -COO-, -OOC-, -CO-, X
₂ -COO -, - shows a _CH 2 O-. A ₁ , A ₂
, A ₃ is Indicates. Y ₁ and Y ₂ represent H or a halogen atom. m and n are 0 or 1. * Indicates that it is optically active. ) 19. The display method according to claim 18, wherein the optically active compound represented by the general formula (I) is any of the following (Ia) to (If). [Chemical 8] _(Wherein, R 1, _{R 2} is .X ₁ showing a straight-chain or branched alkyl group having 1 to 18 carbon atoms is a single bond,
Represents -O-, -COO-, -OOC-, -CO-, X
₂ -COO -, - shows a _CH 2 O-. Y ₁ , Y ₂
Represents H or a halogen atom. * Indicates that it is optically active. ) You. ) 20. The display method according to claim 18, wherein the optically active compound represented by the general formula (I) is any of the following (Iaa) to (Ifa). [Chemical 9] [Chemical 10] (In the formula, R ₁ and R ₂ represent a linear or branched alkyl group having 1 to 18 carbon atoms. * Represents optically active.) 21. In the general formula (I), R ₁ is a linear alkyl group having 3 to 12 carbon atoms, and R ₂ is a linear alkyl group having 1 to 14 carbon atoms. Claim 1
8. The display method described in 8. 22. The display method according to claim 18, wherein the optically active compound represented by the general formula (I) is contained in an amount of 1 to 80% by weight based on the liquid crystal composition. 23. The display method according to claim 18, wherein the optically active compound represented by formula (I) is contained in an amount of 1 to 60% by weight based on the liquid crystal composition. 24. The display method according to claim 18, wherein the optically active compound represented by the general formula (I) is contained in an amount of 1 to 40% by weight based on the liquid crystal composition. 25. The display method according to claim 18, wherein the liquid crystal composition has a chiral smectic phase. 26. The display method according to claim 18, wherein the liquid crystal composition has a nematic phase. 27. A display method using a liquid crystal element comprising a liquid crystal composition containing an optically active compound represented by the following general formula (I), which is disposed between a pair of electrode substrates. [Chemical 11] _(Wherein, R 1, _{R 2} is .X ₁ showing a straight-chain or branched alkyl group having 1 to 18 carbon atoms is a single bond,
Represents -O-, -COO-, -OOC-, -CO-, X
₂ -COO -, - shows a _CH 2 O-. A ₁ , A ₂
, A ₃ is Indicates. Y ₁ and Y ₂ represent H or a halogen atom. m and n are 0 or 1. * Indicates that it is optically active. ) 28. The display method according to claim 27, wherein an alignment control layer is provided on the electrode substrate. 29. The display method according to claim 28, wherein the orientation control layer is a layer subjected to a rubbing treatment. 30. The display method 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.