JPH08225784A - Liquid crystal composition and liquid crystal element and liquid crystal device using the same - Google Patents

Abstract

PURPOSE: To obtain the subject composition, consisting essentially of two kinds of liquid crystalline compounds having specific structures, capable of reducing the temperature dependence of response speed, excellent in contrast and improved in driving characteristics. CONSTITUTION: This composition consists essentially of (A) a compound of the formula R1 -A1 -X1 -A2 -X2 -A3 -R2 [R1 and R2 are each H, CN, etc.; X1 and X2 are each a single bond, O, etc.; A1 to A3 are each a single bond, formula I (R3 is H, a halogen, etc.), etc., with the proviso that at least one of A1 to A3 is formula I or II (R4 is R3 )] and (B) a compound of the formula R5 -A4 -R6 [R5 and R6 are each Q-X3 -(CH2 )L-X4 or R7 (Q is formula III, IV, etc.; X3 is a single bond, OCH2 , etc.; X4 is a signal bond, CH2 O, etc.; L is 3-16; R7 is a 1-18C straight-chain, a branched, a cyclic alkyl, etc.), with the proviso that at least one of R5 and R6 is the former; A4 is A5 -X5 -A6 or A5 -A6 -X5 -A7 (A5 to A7 are each formula V, VI, etc.); X5 is a single bond, CH=CH, etc.]. The composition preferably contains 1-20wt.% each of the components (A) and (B).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal composition used in a liquid crystal display device, a liquid crystal optical shutter, etc., a liquid crystal element, particularly a liquid crystal composition exhibiting ferroelectricity, and a liquid crystal element using the same. The present invention relates to a liquid crystal composition which maintains the temperature characteristics of orientation and optical response and further improves contrast, and a liquid crystal element and a liquid crystal device using the same.

[0002]

2. Description of the Related Art A display device of a type in which transmitted light rays are controlled by using a refractive index anisotropy of ferroelectric liquid crystal molecules in combination with a polarizing element is characterized by Clark and lagerwall. Kai 56-1
07216, U.S. Pat. No. 4,367,924.

This ferroelectric liquid crystal generally has a non-helical chiral smectic C phase (SmC ^* ) or H phase (SmH ^* ) in a specific temperature range, and in this state, it responds to an applied electric field. And has either the first optical stable state or the second optical stable state, and has the property of maintaining that state when no electric field is applied, that is, bistability. It is also expected to be widely used for high-speed and memory-type display elements, and its application is expected to a large-screen and high-definition display especially from the viewpoint of its function.

Conventionally, various problems have been pointed out and solutions have been proposed for such a ferroelectric liquid crystal composition, a ferroelectric liquid crystal element using the same, and a liquid crystal device using the same. There is.

For example, Japanese Patent Application Laid-Open No. 3-252624 proposes a method for improving the transmittance (contrast) in a bistable orientation state, which is called a C1 uniform orientation state from the constituent factors of the element and the orientation state.

That is, the apparent tilt angle θ _a , which is 1/2 of the angle formed by the bistable states of the molecules of the ferroelectric liquid crystal having the non-helical structure in the device, and the characteristics peculiar to the liquid crystal material. The tilt angle Θ (1/2 of the apex angle of the cone where the molecule exists in FIG. 3), the pretilt angle α that is the angle at which the liquid crystal molecules in the same element are inclined with respect to the substrate surface, and the liquid crystal molecules The slant angle δ of the smectic layer formed by the above with respect to the substrate is adjusted to a specific relationship (C1 uniform condition) to improve the contrast.

Generally, as a means for improving the contrast, a method of increasing the tilt angle Θ is known, but if the tilt angle Θ is too large, the condition for realizing the uniform alignment state described above can be satisfied. Disappeared
A C2 orientation state different from the C1 orientation appears, and conversely leads to a decrease in contrast.

Further, the temperature dependence of the tilt angle Θ and the correlation of the response speed may result in deterioration of the temperature dependence of the response speed.

Further, if the tilt angle Θ becomes large, a large torque is required for switching the liquid crystal molecules. If an attempt is made to compensate for this by increasing the spontaneous polarization value (Ps value), This results in an increase in viscosity and, depending on the temperature dependence of the viscosity, results in worsening the temperature dependence of the response speed. Alternatively, it is known that a switching failure is caused depending on the internal electric field induced by the spontaneous polarization value.

On the other hand, in order to improve the temperature dependence of the response speed while satisfying the device conditions for realizing the uniform orientation state, it is known to use a liquid crystal compound having a low viscosity temperature dependence. . As described above, from the viewpoint of responsiveness, too large spontaneous polarization is refrained from, and therefore an improvement method focusing on viscosity becomes important.

By constructing a liquid crystal composition containing a large amount of a low-viscosity liquid crystal compound, it is possible to reduce the temperature change of the viscosity at low temperature to high temperature and improve the temperature dependence of the response speed. In such a composition, the tilt angle Θ is generally small, resulting in a decrease in contrast.

In order to improve other characteristics while maintaining or improving uniform orientation, the ferroelectric liquid crystal does not consist of a single liquid crystal compound,
Since it is a composition composed of various liquid crystal compounds, it is attempted to improve the characteristics by introducing a new liquid crystal compound or a known liquid crystal compound, but various liquid crystal compounds have advantages and disadvantages. It should be easy to understand that they have both.

In other words, when constructing and constructing a ferroelectric liquid crystal composition, it is important to combine liquid crystal compounds so that the merits of various liquid crystal compounds can be fully brought out and the demerits can be supplemented. Therefore, there has been an urgent need for finding a combination of liquid crystal compounds for constructing a well-balanced ferroelectric liquid crystal composition.

On the other hand, in JP-A-60-31120 and JP-A-1-140198, the frame frequency (one screen forming frequency) is lowered as the liquid crystal display device is made larger in screen size and higher in definition. Therefore, an improved driving method has been proposed against the screen rewriting speed, slower moving image display such as character editing, smooth scrolling on a graphic screen, and cursor movement.

That is, a display panel in which scan electrodes and information electrodes are arranged in a matrix, and the total number of scan electrodes, or
It has a means for selecting a predetermined number (when selected by this means is called full writing), and a means for selecting all of the scanning electrodes or a part of a predetermined number (when selecting by this means is called partial writing). The use of a display device.

Thus, by performing partial moving image display by partial writing, high-speed display is possible, and both partial writing and full writing can be realized.

Further, in JP-A-3-35220,
It has been pointed out that the liquid crystal display element needs to have a wide range of drive characteristics called a drive margin in order to realize a large-screen, high-definition ferroelectric liquid crystal display element.

Further, since the driving margin is deviated even when the environmental temperature changes, in the case of an actual display device, it is necessary to set the optimal driving voltage to the liquid crystal material and the environmental temperature.

However, in practical use, when the display area of such a matrix display device is expanded, the difference in the environment in which the liquid crystal exists in each pixel (specifically, the difference in the temperature and the cell gap between the electrodes) is natural. There has been a problem that a liquid crystal having a large driving voltage margin cannot obtain a good image in the entire display area.

[0020]

DISCLOSURE OF THE INVENTION An object of the present invention is to reduce the temperature dependence of response speed, to provide a liquid crystal composition having excellent contrast and improved driving characteristics, a liquid crystal device using the same, and It is to provide a liquid crystal device.

[0021]

The liquid crystal composition of the present invention comprises:
A compound represented by the following general formula 1 and general formula 2 is contained as an essential component.

General formula 1 R ₁ --A ₁ --X ₁ --A ₂ --X ₂ --A ₃ --R ₂ (wherein R ₁ and R ₂ are a hydrogen atom, a halogen or a CN group.

[0023]

[Chemical formula 22] Alternatively, it is a linear, branched, or cyclic alkyl group having 1 to 18 carbon atoms, and one or two or more methylene groups in the alkyl group are -O under the condition that hetero atoms are not adjacent to each other. -, -S-, -CO-, -CHW-, -CH
It may be replaced by ═CH— or —C≡C—, and W represents halogen or CF ₃ . Further, R ₁ and R ₂ may each independently be optically active.

[0024]

[Chemical formula 23]

Or a linear or branched alkyl group having 1 to 18 carbon atoms, one of the alkyl groups,
Alternatively, two or more methylene groups are -O-, -S-, -CO-, -CHW-,-under the condition that hetero atoms are not adjacent to each other.
It may be replaced by CH = CH-, -C≡C-, and W represents halogen or CF ₃ . In addition, R ₃ , R ₄
Each may independently be optically active.

Y ₁ and Y ₂ are H, F, Cl, Br and C
Indicates H _3, CF ₃ or CN, Z is -O- or -S-
Indicates.

However, at least one of A ₁ , A ₂ and A ₃ is

[0028]

[Chemical formula 24]

In this case, preferably A ₁ , A ₂ , A ₃
The remaining two do not become single bonds at the same time.

General formula 2 R ₅ -A ₄ -R ₆

[0031]

[Chemical 25]

L is an integer of 3 to 16, R ₇ is a linear, branched, or cyclic alkyl group having 1 to 18 carbon atoms (one or two of the alkyl groups are included). The above methylene group is -O- under the condition that hetero atoms are not adjacent to each other.
-S-, -CO-, -CHW-, -CH = CH-, -C
≡C- may be replaced by, W is a halogen, CN, a CF _3. ),

[0033]

[Chemical formula 26] A ₄ is, -A ₅ -X ₅ -A ₆ - or -A ₅ -A ₆ -X ₅ -A ₇
-Indicated.

A ₅ , A ₆ , and A ₇ are independent of each other,

[0035]

[Chemical 27] (Y ₉ , Y _9'are each independently H, F, CH ₃ , CF
_It is selected from the _three . ), A ₅ ,
At least one of A ₆ and A ₇

[0036]

[Chemical 28] Is one of.

[0037]

[Chemical 29]

Further, according to the present invention, there is provided a liquid crystal element comprising a pair of substrates which are opposed to each other with the liquid crystal sandwiched therebetween and on which electrodes for applying a voltage to the liquid crystal are formed on the opposing surfaces. Provided is a liquid crystal element which has an alignment control layer for controlling the alignment state of liquid crystal on at least one of the opposite surfaces of the substrates, and uses a liquid crystal composition containing the above two components as essential components as the liquid crystal.

Further, according to the present invention, there is provided a liquid crystal device comprising the above liquid crystal element and a drive circuit for the element.

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION The liquid crystal composition of the present invention contains two kinds of compounds represented by the general formulas (1) and (2) as essential components. These two kinds of compounds are preferably liquid crystal compounds which exhibit a liquid crystal phase independently, but whether or not they take a liquid crystal phase independently is not limited as long as they can suitably function as a liquid crystal component in the composition.

The liquid crystal composition of the present invention preferably contains at least one kind of optically active compound in addition to the above essential components, exhibits a chiral smectic phase, and functions as a ferroelectric liquid crystal.

Further, in the liquid crystal composition of the present invention, the clarification is not yet well understood, but if it is intentionally explained, the present inventors have found that the compound represented by the general formula 1 has an indane skeleton. , It is considered that the characteristics of the compound represented by the general formula 2 bring about the characteristics of mutually drawing out the merits and complementing the demerits by the interaction with the skeleton having the group of the cyclic structure at the terminal of the methylene side chain. To be

For example, due to the effect of lowering the degree of order in the smectic phase of liquid crystal molecules which may increase the viscosity of the liquid crystal composition as a whole, the speed is lowered due to an extreme increase in viscosity at low temperatures. As a result, it has the effect of reducing the temperature dependence of the response speed, and further adjusts the material properties of the liquid crystal composition (tilt angle Θ, layer tilt angle δ) to satisfy the specific device configuration. It also has the property of doing. Therefore, it is considered that high contrast was realized and the temperature dependence of the response speed could be reduced. Furthermore, we will promote the maintenance and improvement of uniform orientation characteristics of the device as described below.

In the present invention, the compound represented by the general formula 1 is preferably a compound represented by the following general formula 3.

General formula 3 R ₈ -A ₈ -A ₉ -A ₁₀ -R ₉ (wherein R ₈ and R ₉ are linear, branched or cyclic having 1 to 18 carbon atoms) An alkyl group, and one or two or more non-adjacent methylene groups in the alkyl group are -O-,-under the condition that hetero atoms are not adjacent.
S-, -CO-, -CHW-, -CH = CH-, -C≡
It may be replaced by C-, and W represents a halogen or CF ₃ group. R ₈ and R ₉ may each independently be optically active.

A ₈ , A ₉ and A ₁₀ are single bonds, or

[0047]

Embedded image At least one of A ₈ , A ₉ , and A ₁₀ is

[0048]

[Chemical 31]

The compound represented by the general formula 1 or 3 is
For example, it can be synthesized by the method described in JP-A-5-262678. The compounds represented by formula 1 or 3 are exemplified in the above-mentioned publications, but specific examples are shown in the following table in the form of a combination of groups constituting the compound.
The abbreviations in the table represent the following side chain groups, cyclic groups, and linking groups.

[0050]

Embedded image

[0051]

[Chemical 33]

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

Embedded image

The compound represented by the general formula 2 is preferably a compound represented by the following general formula 4.

General formula 4

[0057]

Embedded image R ₁₁ and R ₁₂ are hydrogen atoms or 1 to 18 carbon atoms.
Is a linear, branched, or cyclic alkyl group, and one or two or more methylene groups in the alkyl group are -O-, -S-, under the condition that hetero atoms are not adjacent to each other.
—CO—, —CHW—, —CH═CH—, —C≡C—, W is halogen, C
An N group and a CF ₃ group are shown. In addition, R ₁₁ and R ₁₂ may independently be optically active. However, either R ₁₁ or R ₁₂ is a hydrogen atom.

A ₁₁ , A ₁₂ , A ₁₃ , and A ₁₄ are single bonds,

[0059]

Embedded image

[0060] provided that one of A _11, A ₁₄ is a single bond, rather than a single bond simultaneously, A _12, A
_At least one of ₁₃ is a single bond.

N and m are 0 or an integer of 3 to 16. However, one of them is 0 and never 0 at the same time.

[0062]

Embedded image

The compound represented by the above general formula 2 or 4 is
For example, it can be synthesized by the method described in JP-A-6-256231. Although preferable examples of these compounds are also exemplified in the above-mentioned publication, the compounds represented by the general formula 2 or 4
Specific examples of the compound represented by are shown in the following table in the form of a combination of groups constituting the compound. The abbreviations in the table are the same as above, but the following abbreviations are also used.

[0064]

[Chemical 38]

[0065]

[Table 3]

In Table 3, 2-1 to 2-8 and 2-10 are R
₅ is R _7, R ₆ is _{Q-X 3 - (CH 2} ) L X 4 -, 2-9 is R _5, R ₆ together _{Q-X 3 - (CH 2} ) L -X 4 - a and, Q About Y ₃ to Y ₆ is H unless otherwise specified.

Tables 4 to 10 show specific examples of the general formula 4.

[0068]

[Table 4]

[0069]

[Table 5]

[0070]

[Table 6]

[0071]

[Table 7]

[0072]

[Table 8]

[0073]

[Table 9]

[0074]

[Table 10]

In the liquid crystal composition of the present invention, preferably, the compound represented by the general formula (1) or (3) and the compound represented by the general formula (2) or (4) are used in an amount of 1 for each component. -40 wt%, more preferably 1-
30 wt%, most preferably 1 to 20 wt% each. This prescription is appropriately set to adapt to the required contrast level and alignment state.

The optically active compound contained in the liquid crystal composition of the present invention is a compound having the structure of the general formula (1) or (3), (2) or (4), or a phenyl ring or a pyrimidine ring. A compound having a side chain having various optical sites with respect to the central skeleton is preferably used.

In the present invention, other preferable compounds constituting the liquid crystal composition, excluding the above-mentioned essential components and optically active compounds, include the following general formulas (5) to (5).
A liquid crystal compound having the structure (8) can be mentioned. These compounds are used as main constituent components, that is, base liquid crystals, and preferably 20 to 75% by weight, 5 to 25% by weight, 5 to 30% by weight, respectively, of the liquid crystalline compounds represented by the general formulas (5) to (8). It is preferable to use 0.1 to 30% by weight of the liquid crystal compound to appropriately change the compounding ratio of each liquid crystal compound to form a liquid crystal composition.

[0078]

[Chemical Formula 39] (P and q are 0, 1, and 2, p + q is 1 or 2, Y ₁₀ represents a hydrogen atom or a fluorine atom, R ₂₁ ,
R ₂₂ is a linear or branched alkyl group having 1 to 18 carbon atoms, and one or more methylene groups in the alkyl group are -O-,-under the condition that hetero atoms are not adjacent.
S-, -CO-, -CHW-, -CH = CH-, -C≡
C-may be substituted, W is a halogen atom,
A CN group and a CF ₃ group are shown. Further, R ₂₁ and R ₂₂ may be optically active. )

[0079]

[Chemical 40] (Y ₀ represents a hydrogen atom or a fluorine atom, Y ₁₁ represents a hydrogen atom or a fluorine atom, and R ₂₃ represents 1 carbon atom.
To 18 are linear or branched alkyl groups, R ₂₄ is a hydrogen atom, a halogen atom, a CN group, or a carbon number of 1 to 1.
8 is a linear or branched alkyl group, and one or more methylene groups in the alkyl groups represented by R ₂₃ and R ₂₄ are —O—, —S under the condition that hetero atoms are not adjacent to each other. -,
-CO-, -CHW-, -CH = CH-, -C≡C-, W may be a halogen atom or CN.
Group and CF ₃ group. R ₂₃ and R ₂₄ may be optically active. )

[0080]

Embedded image (R ₂₅ and R ₂₆ are linear or branched alkyl groups having 1 to 18 carbon atoms, and one or two or more methylene groups in the alkyl group may have a structure in which hetero atoms are not adjacent to each other.
O-, -S-, -CO-, -CHW-, -CH = CH
-, - C≡C- may be replaced with, W is a halogen atom, CN group, CF ₃ group. Also, R ₂₅ and R ₂₆
May be optically active. )

[0081]

Embedded image (R ₂₇ and R ₂₈ are linear or branched alkyl groups having 1 to 18 carbon atoms, and one or two or more methylene groups in the alkyl group may be a group represented by the formula:
O-, -S-, -CO-, -CHW-, -CH = CH
-, - C≡C- may be replaced with, W is a halogen atom, CN group, CF ₃ group. Also, R ₂₇ and R ₂₈
May be optically active. ) More preferably, as the other liquid crystal compound that constitutes the liquid crystal composition, for example, can be a base liquid crystal, the following general formula (5-1)
~ (5-7), (6-1) ~ (6-5), (7-1) ~
Liquid crystal compounds having the structures of (7-9) and (8-1) to (8-6) are mentioned. The abbreviations in the formula (R _{21 to} R ₂₈
And Y ₁ ) are the same as those used in the general formulas (5) to (8).

[0082]

[Chemical 43]

Particularly preferably, the formulas (5-1) to (5)
-5) a bicyclic phenylpyrimidine derivative,
R ₂₁ is a linear alkyl group having 4 to ₁₄ carbon atoms, R ₂₂ is a linear alkyl group having 4 to 12 carbon atoms, and 3 of the general formulas (5-6) to (5-7) A cyclic phenylpyrimidine derivative in which R ₂₁ is a linear alkyl group having 4 to ₁₄ carbon atoms and R ₂₂ is a linear alkyl group having 4 to 10 carbon atoms is used.

[0084]

[Chemical 44]

Particularly preferably, the formulas (6-1) to (6)
The compound of -5), wherein R ₂₃ is a straight chain alkyl group having 4 to 14 carbon atoms and R ₂₄ is a straight chain alkyl group having 2 to 10 carbon atoms is used.

[0086]

Embedded image

Particularly preferably, the formulas (7-1) to (7)
-9), wherein R ₂₅ has 2 to 5 carbon atoms
A compound in which 10 is a linear alkyl group and R ₂₆ is a linear alkyl group having 2 to 12 carbon atoms is used.

[0088]

Embedded image

Particularly preferably, the formulas (8-1) to (8)
As the compound of (6), a compound in which R ₂₇ is a linear alkyl group having 2 to 10 carbon atoms and R ₂₈ is a linear alkyl group having 4 to 12 carbon atoms is used.

Further, more preferably, the liquid crystal composition has a chiral smectic C phase and has a temperature of 0 ° C. to 60 ° C.
It is desirable that the inclination angle δ of the layer in the chiral smectic C phase as a characteristic peculiar to the material is adjusted to 3 ° or more and 15 ° or less in the temperature range of.

Further, the liquid crystal composition of the present invention exhibits good orientation when a device is formed, and in order to obtain a monodomain function, preferably from an isotropic phase to a chiral nematic phase (cholesteric phase) at a lowered temperature. ), A smectic A phase, and a chiral smectic phase.

The liquid crystal element of the present invention has a structure in which the above-mentioned liquid crystal composition, particularly a liquid crystal composition exhibiting a chiral smectic phase, is sandwiched between a pair of substrates provided with electrodes for applying a voltage to the liquid crystal. Take At least one of the pair of substrates is provided with an alignment control layer that has been subjected to an alignment treatment as needed to control the alignment state of the liquid crystal.

Preferably, in the liquid crystal device using the above chiral smectic liquid crystal, when the pretilt angle near room temperature is α, the tilt angle of the liquid crystal is Θ, and the tilt angle of the liquid crystal layer is δ, the chiral smectic liquid crystal is
It has an alignment state represented by the following formula (I) and preferably formula (II), and exhibits at least two stable states in this alignment state, and at an angle ½ of the angle formed by these optical axes. It is desirable that the apparent tilt angle θ _a and the tilt angle Θ have the relationship of the following formula (III).

Θ <α + δ (I) δ <α (II) Θ> θ _a > Θ / 2 (III)

The reason why it is preferable to satisfy such a relationship will be described with reference to the drawings.

Generally, in the case of a liquid crystal element utilizing the birefringence of liquid crystal, the transmittance I / I ₀ under the crossed Nicols is expressed by the following equation. From this equation, the transmittance I / I ₀ is increased and displayed. It is understood that the apparent tilt angle θ _a (details described later) is preferably 22.5 ° in order to improve the quality.

I / I ₀ = sin4θ _a sin ² (Δnd / λ) π (where I ₀ is the incident light intensity, I is the transmitted light intensity, θ _a is the apparent tilt angle, and Δn is the refractive index anisotropy. , D is the thickness of the liquid crystal layer, and λ is the wavelength of incident light.

The apparent tilt angle θ _a in the liquid crystal device in which the helical structure of the liquid crystal molecule is released in the major axis direction according to the above-mentioned Clark-Lager-Wall type model is the same as that of the device in the first and second alignment states. It appears as the angle of the average molecular axis direction of the liquid crystal molecules twist-arranged in the thickness direction (normal direction of the substrate).

However, for example, in a ferroelectric liquid crystal having a helical structure of liquid crystal molecules obtained by orienting a uniaxially oriented polyimide film as an orientation control layer, an apparent tilt angle θ _a (two stable The angle 1/2 formed by the molecular axes of the state is smaller than the tilt angle (1/2 angle Θ of the apex angle of the triangular pyramid shown in FIG. 3) which is a characteristic of the ferroelectric liquid crystal material, and is generally 3 The transmittance I / I ₀ at that time was about 3 to 5%, which was low.

By the way, smectic liquid crystals generally have a layered structure, but when the SmA phase transitions to the SmC phase or the SmC ^* phase, the liquid crystal layer represented by 21 as shown in FIG. Takes the structure (chevron structure) bent at. As shown in the figure, the bending direction is mixed in the portion 22 in the orientation state (C1 orientation state) that appears immediately after the transition from the high temperature phase to the SmC ^* phase, and in the C1 orientation state when the temperature is further lowered. In the case of the portion 23 of the appearance alignment state (C2 alignment state), there are two possible cases. In addition to two low-contrast stable states (hereinafter referred to as a twisted state) in which the director of the liquid crystal is conventionally twisted between the upper and lower substrates in the C1 orientation, the director of the liquid crystal is located on the upper and lower substrates. It was discovered that two other high-contrast states (hereinafter referred to as uniform states) with reduced twist appear.

These states transit to each other when an electric field is applied, transition between twist 2 states occurs when a weak positive and negative pulse electric field is applied, and transition between uniform 2 states occurs when a strong positive and negative pulse electric field is applied. But C1
It was found that the use of the uniform 2 state in the oriented state causes _a large apparent tilt angle θ _a, and can realize a display device which is brighter and has higher contrast than the conventional one.

Therefore, as the display element, the entire screen is unified in the C1 orientation state, and the high contrast 2 in the C1 orientation is obtained.
If the state (uniform state) is used as two states of monochrome display, it is expected that a display of higher quality than ever can be realized.

Here, the directors near the substrate in the C1 orientation and the C2 orientation are respectively on the cone 31, as shown in FIGS. 3 (a) and 3 (b). As is well known, the liquid crystal molecules at the substrate interface form an angle called pretilt with respect to the alignment control film that has been uniaxially aligned such as rubbing, and the direction is the rubbing direction (see FIG. 3).
In the directions (A) and (b), the liquid crystal molecules hang their heads (the tips become floating).

From the above, the tilt angle Θ of the liquid crystal,
Between the pretilt angle α and the layer inclination angle δ (the angle formed by the liquid crystal layer and the substrate normal) δ, the relation of Θ + δ> α for C1 orientation and Θ−δ> α for C2 orientation must be established. .

Therefore, the condition for producing the C1 orientation without producing the C2 orientation is Θ−δ <α, that is, Θ <α + δ (I).

Further, from the simple consideration of the torque received when the liquid crystal molecules near the substrate interface are transferred from one position to the other position by the electric field, α> δ (II) is set as a condition that the interface molecules are easily switched. Is obtained.

Therefore, the C1 → C2 transition is unlikely to occur,
It can be understood that in order to form the C1 orientation state more stably, it is effective to satisfy the relationship of the formula (II) in addition to the relationship of the formula (I).

When the above conditions (I) and (II) are satisfied, the apparent tilt angle θ _a of the liquid crystal is
The angle increases from about 3 ° to 8 ° to about 8 ° to 16 °, and between the tilt angle Θ of the liquid crystal and the apparent tilt angle θ _a , Θ> θ _a > Θ / 2 (III) The relational expression holds.

As described above, (I), (II) and (II
It has been clarified that a display on which a high-contrast image is displayed can be realized if the condition of the formula (I) is satisfied.

The liquid crystal element of the present invention uses the above-mentioned liquid crystal composition, for example, forms a specific alignment control layer for aligning liquid crystals on the opposing surfaces of both substrates, and subject at least one of them to a uniaxial alignment treatment. And the uniaxial alignment treatment axes for aligning the liquid crystal are parallel or intersect at a predetermined angle, and preferably (I), (II) and (II
The alignment state of the liquid crystal is controlled so as to satisfy the condition I).

In order to stably form the above-mentioned C1 orientation state and further uniform orientation and obtain good orientation, it is more preferable to intersect the uniaxial orientation treatment axes of both substrates within a range of more than 0 ° and 25 ° or less. Let Further, the magnitude of the pretilt angle α in the liquid crystal element of the present invention is preferably 5 ° or more.

Hereinafter, a general structural example of the liquid crystal element of the present invention will be described with reference to FIG.

The liquid crystal element is composed of two glass substrates 11
a, 11b, and these glass substrates 11a,
On the surface of 11b, transparent electrodes 12a,
12b are formed respectively. This transparent electrode 12
a and 12b are In ₂ O ₃ .SnO ₂ or ITO (Indium-Tin: Indium-Tin).
Oxide) and other thin films.

The transparent electrodes 12a and 12b are the insulating film 13
a, 13b and alignment control films 14a, 14b.

The insulating films 13a and 13b are made of, for example, silicon nitride, silicon carbide containing hydrogen, silicon oxide, boron nitride, boron nitride containing hydrogen,
The counter substrate is formed of an inorganic material such as cerium oxide, aluminum oxide, zirconium oxide, titanium oxide, or magnesium fluoride or another organic insulating material, and has at least one layer or, if necessary, a multi-layer structure. It has the function of preventing short circuit between (electrodes). Further, a coating type insulating film such as Ti-Si may be formed on the organic or inorganic insulating film for preventing the short circuit described above. Further, in order to solve the movement phenomenon of liquid crystal molecules during driving as a cell structure, an insulating coating film containing insulating beads such as SiO ₂ beads may be provided to roughen the alignment control film as an upper layer. Yes (not shown).

The alignment control films 14a and 14b are made of polyvinyl alcohol, polyimide, polyamide imide, polyester imide, polyparaxylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride,
It can be formed of an organic insulating material such as polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, acrylic resin or photoresist resin, or other inorganic insulating material. The insulating films 13a and 13b and the orientation control films 14a and 14b are not divided into two or more layers as described above, if necessary, and the inorganic material insulation orientation control layer or the organic material insulation orientation control layer is a single layer. Can also be

As the orientation control films 14a and 14b, specifically, for example, a polyimide obtained from a precursor composed of a repeating unit represented by the following structural formula is used.

[0118]

[Chemical 47]

Further, at least one of the orientation control films 14a and 14b is subjected to orientation treatment such as rubbing treatment with gauze or acetate flock cloth regardless of whether it is a double layer or a single layer.

The insulating films 13a and 13b and the orientation control films 14a and 14b can be formed by a vapor deposition method or the like if it is an inorganic type, and if it is an organic type, a solution in which an organic insulating material is dissolved or a precursor solution thereof. (0.1 to 20% by weight, preferably 0.2 to 10% by weight in a solvent) is applied by spinner coating method, dip coating method, screen printing method, spray coating method, roll coating method, etc. It can be formed by curing under the curing conditions of (for example, under heating).

The thickness of the insulating films 13a and 13b and the orientation control films 14a and 14b is usually 3 to 1000 nm.
Preferably 3 to 300 nm, more preferably 4 to 10 nm.
0 nm is suitable.

When such a liquid crystal element is applied as a color display element, at least one of the glass substrates 11a and 11b is composed of dots or lines made of various color members such as R, G, B and W. A color filter pattern is provided (not shown). The color filter pattern is formed on the substrate and can be covered with a flattening layer made of an inorganic material or an organic material in order to reduce the step difference between lines and dots forming the pattern. In addition, a black light-shielding layer made of a metal or a resin material is preferably provided between the dots or lines of the color filter to prevent color mixing (not shown). In such a color display element, the pattern of the transparent electrodes 11a and 11b can be set according to the shape of the color filter pattern.

On the other hand, the above-mentioned two glass substrates 11a,
Spacers 16 are scattered between 11b, and the glass substrates 11a and 11b are spaced by a predetermined distance (cell gap; generally 0.1 to 20 μm, by this spacer 16).
It is preferably maintained at 0.5 to 3 μm).

As the spacer 16 for holding the cell gap, silica beads, alumina beads, a polymer film, glass fibers, and a space between the substrates formed by the spacer are held to improve the impact resistance of the device. A granular adhesive (not shown) or the like is used.

Further, the periphery of the glass substrates 11a and 11b is adhered by a sealing agent such as an epoxy adhesive (not shown), and the glass substrates 11a and 11b are provided with the above-described structure of the present invention. A chiral smectic liquid crystal is enclosed.

On the other hand, polarizing plates 17a and 17b are attached to the outside of the glass substrates 11a and 11b.

The alignment control films 14a and 14b are, for example, counterclockwise when the alignment control film 14a on the upper side is viewed from the alignment control film 14a on the upper side with respect to the alignment control film 14b on the lower side. For example, uniaxial orientation treatment such as rubbing treatment is performed so that the crossing angle is ± 25 ° or less and the same direction (direction of arrow A in FIG. 3). In the present invention, the intersection angle is defined as described above.

In the above liquid crystal element, when a transmissive display element is used, a light source (not shown) is provided on the back side of one substrate.

The liquid crystal element according to the present invention constitutes a liquid crystal device having various functions. For example, in addition to the liquid crystal element, a means for driving the liquid crystal element and a light source serving as a backlight are provided to form a liquid crystal display device. Specifically, by using the liquid crystal element in the display panel section and taking a communication synchronizing means by a data format and an SYNC signal which is image information having scanning line address information shown in FIGS. 6 and 7, a liquid crystal display device is obtained. To realize.

The image information is generated by the graphic controller 102 on the main body side and transferred to the display panel 103 according to the signal transfer means shown in FIGS. 6 and 7. The graphic controller 102 includes a CPU (Central Processing Unit, hereinafter abbreviated as GCPU 112) and a VR.
With the AM (memory for storing image information) 114 as the core, the host C
It manages image information and communicates between the PU 113 and the liquid crystal display device 101, and the liquid crystal display device control method using the liquid crystal element according to the present invention is mainly realized on the graphics controller 102. .

Next, the driving method applied to the liquid crystal element of the present invention will be described.

In the case of a simple matrix display device using an element in which this ferroelectric liquid crystal layer is sandwiched between a pair of substrates, for example, JP-A-59-193426 and JP-A-59-1.
No. 93427, JP-A-60-156046,
The driving method disclosed in JP-A-60-156047 can be applied.

FIG. 8 is an example of a waveform diagram of the above driving method. Further, FIG. 5 is a plan view of an example of a chiral smectic liquid crystal panel in which matrix electrodes are arranged. Figure 5
In the liquid crystal panel 51, the scanning lines of the scanning electrode group 52 and the data lines of the information electrode group 53 are wired so as to intersect with each other, and the chiral smectic liquid crystal is arranged between the scanning lines and the data lines at the intersections. Has been done.

In FIG. 8A, S _S is a selected scan waveform applied to the selected scan line, S _N is a non-selected scan waveform not selected, and I _S is applied to the selected data line. selection information waveform (black), I _N represents the non-selection information signal applied to the data line which is not selected (white). In the figure the _{(I S -S S) (I} N -S S) is the voltage waveforms applied to pixels on a selected scanning line, the voltage (I _S -S _S) is applied pixel black take the display state, the voltage (I _N -
The pixel to which S _S ) is applied has a white display state.

FIG. 8B shows the drive waveform shown in FIG. 8A, which is a time-series waveform when the display shown in FIG. 9 is performed.

In the driving example shown in FIG. 8, the minimum application time Δt of the single polarity voltage applied to the pixel on the selected scanning line.
Corresponds to the time of the write phase t _{2, and} the time of the 1-line clear t ₁ phase is set to 2Δt.

The values of the parameters V _S , V _I and Δt of the drive waveform shown in FIG. 8 are determined by the switching characteristics of the liquid crystal material used.

FIG. 10 shows that the bias ratio described later is kept constant.
Drive voltage (V_S+ V_I) Transmissivity T when is changed
Of VT characteristics, that is, VT characteristics. here
Δt = 50 μsec, bias ratio V _I/ (V_I+ V_S) =
It is fixed at 1/3. The positive side of FIG. 10 is shown in FIG.
(I_N-S_S), The negative side is (I_S-S_S) Waveform is applied
Is done. The waveform (I_N-S_S) And (I_S-S_S) Then,
V_RThe previous state is cleared by the_B ¹, V_B ²To
Then, the next write state is determined.

Here, V ₁ and V ₃ are called the actual driving threshold voltage and the crosstalk voltage, respectively. Also, V ₂ <V ₁ <V ₃
At that time, ΔV = V ₃ −V ₁ is called a voltage margin, which is a parameter of the voltage width capable of matrix driving. V ₁ is shown in FIG.
It is a voltage value that causes switching by V _B ^{2 in} (A). It can be said that V ₃ is generally present in driving a chiral smectic liquid crystal display device. Specifically, FIG.
A voltage value causing switching by V _B ¹ in the waveform of _{(A) (I N -S S} ). Of course, it is possible to increase the value of V ₃ by increasing the bias ratio, but increasing the bias ratio means increasing the amplitude of the information signal, which causes an increase in image flicker and contrast. Is caused, which is not preferable.

According to our study, the bias ratio is 1/3 to 1/4.
The degree was practical. By the way, if the bias ratio is fixed, it goes without saying that the voltage margin ΔV strongly depends on the switching characteristics of the liquid crystal material and the element configuration, and an element having a large ΔV is very advantageous for matrix driving.

At such a constant temperature, it is possible to write two states of "black" and "white" to the selected pixel depending on the two directions of the information signal, and the non-selected pixel has the "black" or "white" state. The voltage margin or the voltage application time margin capable of maintaining the “white” state is unique because there is a difference depending on the liquid crystal material and the element configuration. Also,
Since the drive margin shifts even if the environmental temperature changes, in the case of an actual display device, it is necessary to set the optimal driving conditions for the liquid crystal material, the element configuration, and the environmental temperature.

The tilt angle Θ, the apparent tilt angle θ _a , the tilt angle δ of the liquid crystal layer, the pretilt angle α and the spontaneous polarization Ps in the liquid crystal device according to the present invention can be measured as follows.

[Measurement of tilt angle Θ] ± 30 to ± 50
While applying AC (alternating current) of V, 1 to 100 Hz through the electrodes between the upper and lower substrates of the liquid crystal element, the liquid crystal element placed between them under DC crossed Nicols is rotated in parallel with the polarizing plate, and at the same time, the photo (Hamamatsu Photonics Co., Ltd.
The first extinction position (the position where the transmittance is the lowest) and the second extinction position are obtained while detecting the optical response of the product. Then, 1/2 of the angle from the first extinction position to the second extinction position at this time is defined as the tilt angle Θ.

[0144] After applying the single pulse of the liquid crystal threshold Measurement of tilt angle theta _a apparent, electroless under and under DC crossed Nicols, rotating the liquid crystal element disposed therebetween in parallel with the polarizing plate , Find the first extinction position. Next, after applying a pulse of the opposite polarity to the single pulse above,
The second extinction position is obtained under no electric field. At this time, 1/2 of the angle from the first extinction position to the second extinction position is an apparent tilt angle θ _a .

[Measurement of Inclination Angle δ of Liquid Crystal Layer] Basically,
The method used by Clark and Lagerfor (Ja
panDisplay '86, Sep. 30-O
ct. 2, 1986. 456-458) or the method of Ouchi et al. (JJAP 27 (5) (19).
88) Measured by the same method as 725 to 728).
A rotating cathode X-ray analyzer (manufactured by MAC Science) was used as a measuring device, and a microsheet (80 μm) manufactured by Corning was used for the substrate in order to reduce absorption of X-rays into the glass substrate of the liquid crystal cell. .

[Measurement Method of Pretilt Angle α] The pretilt angle α is measured by the crystal rotation method (Jp
a. J. Appl. Phys. Vo. 119 (1
980) No. Short Notes 203
It was determined by 1). The liquid crystal for measuring the pretilt angle α is a ferroelectric liquid crystal (CS-1014 manufactured by Chisso Corporation).
A mixture of 20% by weight of a compound represented by the following structural formula was injected as a standard liquid crystal and measured.

[0147]

Embedded image

The mixed liquid crystal composition had a composition of 10-55.
It showed an SmA phase at ° C.

The measurement procedure is as follows. While rotating the liquid crystal panel having the target alignment control layer on the plane perpendicular to the upper and lower substrates and including the alignment treatment axis (rubbing axis), the polarization plane forming an angle of 45 ° with the rotation axis is measured. The helium-neon laser light was emitted from the direction perpendicular to the rotation axis, and the transmitted light intensity was measured with a photodiode through a polarizing plate having a transmission axis parallel to the incident polarization plane on the opposite side. Then, the pretilt angle α was obtained from the spectrum of the transmitted light intensity generated by the interference by a theoretical curve and the following equation and a simulation for fitting.

[0150]

[Equation 1]

[Measurement of spontaneous polarization (Ps) value] Miyasato et al. "Direct measurement method of spontaneous polarization of ferroelectric liquid crystal using triangular wave" (Journal of the Japan Society of Applied Physics 22 and 10).
Issue (661) 1983, "Direct Method"
with Triangular Waves fo
r Measuring Spontaneous P
polarization in Ferrolectr
ic Liquid Crystal ”, as des
crib by K. Miyasato et a
l. (Jap. J. Appl. Phys. 22. No.
10, L661 (1983))).

[0152]

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 (1) A liquid crystal composition A was prepared by mixing the compounds having the following structures in the following parts by weight.

[0154]

[Chemical 49]

The liquid crystal composition A had a phase transition temperature of 30
The magnitude of spontaneous polarization (Ps) and the tilt angle (Θ) at ° C are shown below.

[0156]

Embedded image

Next, the cells prepared by the procedure showing the orientation and the optical response showing the uniform property of these liquid crystal compositions were observed.

A thin film of tantalum oxide was formed on a glass substrate having a transparent electrode by a sputtering method, and polyamic acid LQ1 manufactured by Hitachi Chemical Co., Ltd., represented by the above structural formula 1, was formed on the thin film.
802 1% NMP solution is applied with a spinner and 270
Calcination was carried out at ℃ for 1 hour.

Next, this substrate was rubbed, and another substrate subjected to the same treatment had a crossing angle of 10 ° (described above), and a gap of about 1.2 to 1.3 μm was formed so as to be in the same direction. A cell was created by keeping and pasting. The pretilt angle α of the cell is 17 ° by the crystal rotation method.
Met.

A liquid crystal element was prepared by injecting the liquid crystal composition A into this cell in an isotropic liquid state and gradually cooling from the isotropic phase to 25 ° C. at 20 ° C./h.

Using this liquid crystal element, the orientation showing uniform properties was observed. As a result, 95% of the liquid crystal elements had an orientation showing a uniform property, but 5% had a twist orientation, and the entire surface of the element was observed. No uniform uniform orientation was obtained over the entire length.

The tilt angle δ of the smectic layer and the apparent tilt angle θ _a of the liquid crystal composition and the device using the same were measured and found to be 12.0 ° and 12.5.
It was °.

Using this liquid crystal element, the drive margin ΔV (V _{3 is obtained with the} drive waveform (1/3 bias ratio) shown in FIG.
-V ₁₎ was observed. (Note that Δt was set so that V ₁ ≈15 V.) The results are shown below.

[0164]

[Table 11]

The contrast ratio at 30 ° C. was 28.

(2) 1-AI was produced in the liquid crystal composition by mixing the following exemplary compounds in the liquid crystal composition A in the following parts by weight.

[0167]

[Chemical 51]

The phase transition temperature, the magnitude of spontaneous polarization (Ps) at 30 ° C. and the tilt angle (θ) of this liquid crystal composition 1-AI are shown below.

[0169]

Embedded image

Next, a liquid crystal element was produced by the same method as in (1) above except that this liquid crystal composition 1-AI was used, and alignment and optical properties showing uniform properties were obtained in the same manner as in (1) above. Response was measured. The results are shown below.

Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

When the tilt angle δ and the apparent tilt angle θ _a of the smectic layer were measured in the same manner as in the case of using the composition A, they were 10.3 ° and 10.8 °, respectively.

[0173]

[Table 12]

Further, the contrast ratio at 30 ° C. was measured and found to be 41.

(3) Liquid crystal composition 1-AII was prepared by mixing the following exemplary compounds with liquid crystal composition A of (1) in the following parts by weight.

[0176]

Embedded image

The phase transition temperature, the magnitude of spontaneous polarization (Ps) at 30 ° C. and the tilt angle (θ) of this liquid crystal composition 1-AII are shown below.

[0178]

[Chemical 54]

Next, a liquid crystal element was manufactured by the same method as in (1) above except that this liquid crystal composition 1-AII was used, and alignment and optical properties exhibiting uniform properties were obtained by the same method as in (1) above. Response was measured. The results are shown below.

Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

When the tilt angle δ and the apparent tilt angle θ _a of the smectic layer were measured in the same manner as in the case of using the composition A, they were 9.5 ° and 10.1 °, respectively.

[0182]

[Table 13]

Further, the contrast ratio at 30 ° C. was measured and found to be 42.

(4) The liquid crystal composition A was mixed with the following exemplary compounds in the weight parts shown below to prepare a liquid crystal composition 1-AIII.

[0185]

[Chemical 55]

The phase transition temperature, the magnitude of spontaneous polarization (Ps) at 30 ° C. and the tilt angle (Θ) of this liquid crystal composition 1-AIII are shown below.

[0187]

[Chemical 56]

Next, a liquid crystal element was produced in the same manner as in the above (1) except that this liquid crystal composition 1-AIII was used.
The orientation and optical response exhibiting uniform properties were measured by the same method as in (1) above. The results are shown below.

Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

When the tilt angle δ and the apparent tilt angle θ _a of the smectic layer were measured in the same manner as in the case of using the composition A, they were 9.7 ° and 10.4 °, respectively.

[0191]

[Table 14]

Further, the contrast ratio at 30 ° C. was measured and found to be 48.

Comparative Example 1 (1) The following compounds similar to the exemplified compound 3-4 used in the liquid crystal composition 1-AI used in Example 1 were mixed in the following parts by weight to prepare a liquid crystal composition. 1-AIV was made.

[0194]

[Chemical 57]

The phase transition temperature, the magnitude of spontaneous polarization (Ps) at 30 ° C. and the tilt angle (θ) of this liquid crystal composition 1-AIV are shown below.

[0196]

Embedded image

A liquid crystal device was produced in the same manner as in the above (1) except that this liquid crystal composition 1-AIV was used, and the orientation and the optical response showing the uniform property in the same illegal manner as in the above (1). Was measured. The results are shown below.

Alignment showing uniform property (microscopic observation by visual observation): 95% of the liquid crystal elements had alignment showing uniform property, but 5% had twisted alignment,
Uniform uniform orientation was not obtained over the entire surface of the device.

When the tilt angle δ and the apparent tilt angle θ _a of the smectic layer were measured in the same manner as in the case of using the composition A, they were 12.0 ° and 12.4 °, respectively.

[0200]

[Table 15]

Further, the contrast ratio at 30 ° C. was measured and found to be 32.

As is clear from Example 1 and Comparative Example 1, the liquid crystal composition A of the base has a uniform alignment state in which 5% of twist alignment exists, whereas the liquid crystal composition A has a uniform alignment state. Thing 1-AI, 1-AII,
1-AIII had a uniform uniform orientation.

The temperature characteristics are shown in Exemplified Compounds 3-4, 4-10
And liquid crystal compositions 1-AI and 1-A
II is 3.89, 4.06, while the liquid crystal composition 1-using both of the exemplified compounds 3-4 and 4-10
It can be seen that AIII shows an appropriate temperature characteristic of 3.73. Also, it can be seen that the contrast ratio is significantly improved when both are used at the same time as compared with the case where they are used alone.

Further, as compared with the case where the compounds similar to the exemplified compounds 3-4 and 4-10 were used (Comparative Example 1), the compound of the present invention showed the uniform orientation,
It can be seen that the temperature characteristics and the contrast ratio are improved in a well-balanced manner, and that the drive margin is significantly improved.

[0205]

[Table 16]

Example 2 In place of the exemplary compound used in Example 1, the following exemplary compounds were mixed in the respective parts by weight shown below, and liquid crystal composition 2 was prepared in the same manner as in Example 1.
AI, 2-AII, and 2-AIII were produced, respectively.

[0207]

Embedded image

This liquid crystal composition 2-AI, 2-AII, 2
The phase transition temperature of -AIII and the magnitude of spontaneous polarization (Ps) at 30 ° C and the tilt angle (Θ) are shown below.

Liquid Crystal Composition 2-AI

[0210]

Embedded image

Liquid Crystal Composition 2-AII

[0212]

[Chemical formula 61]

Liquid Crystal Composition 2-AIII

[0214]

Embedded image

Next, the liquid crystal compositions 2-AI, 2-AI
A liquid crystal device was produced in the same manner as in Example 1 except that I and 2-AIII were used, and the orientation and optical response showing a uniform shape were measured in the same manner as in Example 1. Further, the contrast ratio at 30 ° C. was also measured. The results are shown below.

Liquid Crystal Composition 2-AI Orientation showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

[0219]

[Table 17] Contrast ratio at 30 ° C: 41

Liquid Crystal Composition 2-AII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal device.

[0219]

[Table 18] Contrast ratio at 30 ° C: 31

Liquid Crystal Composition 2-AIII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

[0221]

[Table 19] Contrast ratio at 30 ° C: 49

As is clear from Example 2, the liquid crystal compositions 2-AI, 2-AII,
All of the liquid crystal devices using 2-AIII showed uniform uniform alignment, but the temperature characteristics were the same as those of Exemplified Compound 3
Liquid crystal compositions 2-AI and 2-AII in which each of -22 and 4-86 are used alone are 4.18 and 4.32.
(F ^10/40 ) while the exemplary compound 3-22,
The liquid crystal composition 2-AIII in which both 4-86 were used had a value of 4.00, indicating that the liquid crystal composition 2-AIII exhibits appropriate temperature characteristics. Also, it can be seen that the contrast ratio is better when both of them are used at the same time than when they are used alone. Furthermore, the composition 2-AIII has a significantly improved driving margin.

Example 3 In place of the exemplified compound used in Example 1, the following exemplified compounds were mixed in the respective parts by weight shown below, and the liquid crystal composition 3 was prepared in the same manner as in Example 1.
AI, 3-AII, and 3-AIII were produced, respectively.

[0224]

[Chemical formula 63]

This liquid crystal composition 3-AI, 3-AII, 3
The phase transition temperature of -AIII and the magnitude of spontaneous polarization (Ps) at 30 ° C and the tilt angle (Θ) are shown below.

Liquid Crystal Composition 3-AI

[0227]

[Chemical 64]

Liquid Crystal Composition 3-AII

[0229]

Embedded image

Liquid Crystal Composition 3-AIII

[0231]

[Chemical formula 66]

Next, the liquid crystal compositions 3-AI, 3-AI
A liquid crystal element was produced in the same manner as in Example 1 except that I, 3-AIII was used, and the orientation and optical response showing a uniform shape were measured in the same manner as in Example 1. Further, the contrast ratio at 30 ° C. was also measured. The results are shown below.

Liquid Crystal Composition 3-AI Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

[0234]

[Table 20] Contrast ratio at 30 ° C: 39

Liquid Crystal Composition 3-AII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

[0236]

[Table 21] Contrast ratio at 30 ° C: 43

Liquid Crystal Composition 3-AIII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

[0238]

[Table 22] Contrast ratio at 30 ° C: 54

As is clear from Example 3, at the phase transition temperature of the liquid crystal composition, the liquid crystal composition 3-AII was SmA →
The phase transition point T _c of Sm ^* C is lower and worse than those of the other two compositions.

As for the orientation showing the uniform property, all of the elements using the liquid crystal compositions 3-AI, 3-AII, and 3-AIII showed uniform uniform orientation, but the temperature characteristics were as shown in Example Compound 3-25, Liquid Crystal Composition 3-AI using 3-20 is 5.24 (f ^10/40 ), exemplified compound 4
The liquid crystal composition 3-AI using -18, 4-16, 4-85, 4-90 is 5.13, while the liquid crystal composition 3-AIII using all two series is 4.63. And shows appropriate temperature characteristics. It is also seen that the contrast ratio is better when both systems are used than when each system is used alone. The composition 3-AIII has a significantly improved driving voltage margin.

Example 4 A liquid crystal composition B was prepared by mixing the compounds having the following structures in the parts by weight shown below.

[0242]

Embedded image

The liquid crystal composition B had a phase transition temperature of 30 and
The magnitude of spontaneous polarization (Ps) and the tilt angle (Θ) at ° C are shown below.

[0244]

[Chemical 68]

Next, a liquid crystal element was manufactured in the same manner as in Example 1 except that this liquid crystal composition B was used.
Similarly to the above, the orientation and optical response showing a uniform were measured. Further, the contrast ratio at 30 ° C. was also measured. The results are shown below.

Orientation showing uniform property (visual observation with a microscope): 70% of liquid crystal elements had an orientation showing uniform property, but 30% had a twist orientation, and uniform uniform orientation was obtained over the entire surface of the element. Was not obtained.

The inclination angle δ of the smectic layer and the apparent tilt angle θ _a of the composition B and the device using the composition B were 14.1 ° and 13.7 °.

[0248]

[Table 23] Contrast ratio at 30 ° C: 19

To the liquid crystal composition B, the exemplified compounds shown below were mixed in the following parts by weight, and the liquid crystal compositions 4-BI, 4-BII, 4-BII were prepared in the same manner as in Example 1.
I was prepared respectively.

[0250]

[Chemical 69]

This liquid crystal composition 4-BI, 4-BII, 4
The phase transition temperature of -BIII and the magnitude of spontaneous polarization (Ps) at 30 ° C and the tilt angle (Θ) are shown below.

Liquid crystal composition 4-BI

[0253]

Embedded image

Liquid Crystal Composition 4-BII

[0255]

Embedded image

Liquid Crystal Composition 4-BIII

[0257]

Embedded image

Next, this liquid crystal composition 4-BI, 4-BI
A liquid crystal element was produced in the same manner as in Example 1 except that I, 4-BIII was used, and the orientation and optical response showing a uniform shape were measured in the same manner as in Example 1. Further, the contrast ratio at 30 ° C. was also measured. The results are shown below.

Liquid Crystal Composition 4-BI Orientation showing uniform property (microscopic observation by visual observation): 85% of liquid crystal elements had an orientation showing uniform property, but 15% had a twisted orientation. No uniform uniform orientation was obtained over the entire surface.

When the tilt angle δ and the apparent tilt angle θ _a of the smectic layer were measured in the same manner as in the case of using the composition B, they were 13.3 ° and 14.0 °, respectively.

[0261]

[Table 24] Contrast ratio at 30 ° C: 22

Liquid Crystal Composition 4-BII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over the entire surface of the liquid crystal element.

The tilt angle δ and the apparent tilt angle θ _a of the smectic layer were measured in the same manner as in the case of using the composition B, and they were respectively 8.2 ° and 8.4 °.

[0264]

[Table 25] Contrast ratio at 30 ° C: 41

Liquid Crystal Composition 4-BIII Orientation showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over the entire surface of the liquid crystal element.

When the tilt angle δ and the apparent tilt angle θ _a of the smectic layer were measured in the same manner as in the case of using the composition B, they were 10.9 ° and 11.9 °, respectively.

[0267]

[Table 26] Contrast ratio at 30 ° C: 38

As is clear from Example 4, Exemplified Compound 4
The liquid crystal composition 4-BII using -6 is SmA → Sm
^Since the phase transition point T _c of ^* C was low, the driving margin at 40 ° C. could not be measured.

The liquid crystal composition 4-BI using the exemplified compound 3-26 had a uniform orientation of 15 or more.
%, Uniform uniform orientation was not obtained over the entire surface of the device including the twist orientation.

However, the liquid crystal composition 4-BIII using the exemplified compounds 3-26 and 4-6 shows a uniform uniform orientation over the entire surface of the device, has an optimum temperature characteristic, has a high contrast ratio, and has a very high contrast ratio. It can be seen that the liquid crystal element is well balanced. Furthermore, the driving voltage margin also showed excellent characteristics.

Example 5 In place of the exemplary compound used in Example 4, the following exemplary compounds were mixed in the following parts by weight, and liquid crystal composition 5-B was prepared in the same manner as in Example 1.
I, 5-BII, 5-BIII were produced respectively.

[0272]

Embedded image

This liquid crystal composition 5-BI, 5-BII, 5
The phase transition temperature of -BIII and the magnitude of spontaneous polarization (Ps) at 30 ° C and the tilt angle (Θ) are shown below.

Liquid Crystal Composition 5-BI

[0275]

[Chemical 74]

Liquid Crystal Composition 5-BII

[0277]

[Chemical 75]

Liquid Crystal Composition 5-BIII

[0279]

[Chemical 76]

Next, this liquid crystal composition 5-BI, 5-BI
A liquid crystal element was produced in the same manner as in Example 1 except that I, 5-BIII was used, and the orientation and optical response showing a uniform shape were measured in the same manner as in Example 1. Further, the contrast ratio at 30 ° C. was also measured. The results are shown below.

Liquid Crystal Composition 5-BI Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

[0282]

[Table 27] Contrast ratio at 30 ° C: 40

Liquid Crystal Composition 5-BII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal element.

[0284]

[Table 28] Contrast ratio at 30 ° C: 31

Liquid Crystal Composition 5-BIII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal device.

[0286]

[Table 29] Contrast ratio at 30 ° C: 37

As is clear from Example 5, Exemplified Compound 3
The liquid crystal composition 5-BI using -27 is SmA → Sm
^Since the phase transition point T _c of ^* C was low, the driving margin at 40 ° C. could not be measured.

Exemplified Compounds 4-10, 4-63, 4-16
The liquid crystal composition 5-BII used in Example 5 showed uniform uniform orientation over the entire surface of the device and had a temperature characteristic of 4.17 (f ^10/40 ), but both systems were used. The liquid crystal composition 5-BIII is
A uniform uniform orientation is shown over the entire surface of the element, and the temperature characteristic is 3.88, which shows appropriate characteristics. It is also understood that the contrast ratio is high, which is much better than the case where each system is used alone. Further, the driving voltage margin is also significantly improved.

Example 6 In place of the exemplified compound used in Example 4, the following exemplified compounds were mixed in the following parts by weight, and liquid crystal composition 6-B was prepared in the same manner as in Example 1.
I, 6-BII, 6-BIII were produced respectively.

[0290]

Embedded image

This liquid crystal composition 6-BI, 6-BII, 6
The phase transition temperature of -BIII and the magnitude of spontaneous polarization (Ps) at 30 ° C and the tilt angle (Θ) are shown below.

Liquid Crystal Composition 6-BI

[0293]

Embedded image

Liquid Crystal Composition 6-BII

[0295]

Embedded image

Liquid Crystal Composition 6-BIII

[0297]

Embedded image

Next, this liquid crystal composition 6-BI, 6-BI
A liquid crystal element was produced in the same manner as in Example 1 except that I, 6-BIII was used, and the orientation and optical response showing a uniform shape were measured in the same manner as in Example 1. Further, the contrast ratio at 30 ° C. was also measured. The results are shown below.

Liquid Crystal Composition 6-BI Alignment showing uniform property (visual observation with a microscope): Alignment was extremely poor and measurement was not possible.

[0300]

[Table 30] Contrast ratio at 30 ℃: Not measurable

Liquid Crystal Composition 6-BII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal device.

[0302]

[Table 31] Contrast ratio at 30 ° C: 32

Liquid Crystal Composition 6-BIII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal device.

[0304]

[Table 32] Contrast ratio at 30 ° C: 35

As is clear from Example 6, Exemplified Compound 3
The liquid crystal composition 6-BI containing -30 had a bad phase transition series and was not in a measurable alignment state.

The liquid crystal composition 6-BII using the exemplified compounds 4-10 and 4-85 shows uniform uniform orientation over the entire surface of the device, and has a temperature characteristic of 4.53 (f ^{10 /} f ^{10 / 40} ), the liquid crystal composition 6-BIII using both systems shows uniform uniform orientation over the entire surface of the device and has a temperature characteristic of 4.20, which is at an appropriate level. It is also understood that the contrast ratio is high, which is much better than the case where each system is used alone. Furthermore, the composition 6-BIII also showed excellent characteristics in terms of driving margin.

Example 7 In place of the exemplary compound used in Example 4, the following exemplary compounds were mixed in the following parts by weight, and liquid crystal composition 7-B was prepared in the same manner as in Example 1.
I, 7-BII, 7-BIII were produced respectively.

[0308]

[Chemical 81]

This liquid crystal composition 7-BI, 7-BII, 7
The phase transition temperature of -BIII and the magnitude of spontaneous polarization (Ps) at 30 ° C and the tilt angle (Θ) are shown below.

Liquid Crystal Composition 7-BI

[0311]

[Chemical formula 82]

Liquid Crystal Composition 7-BII

[0313]

[Chemical 83]

Liquid Crystal Composition 7-BIII

[0315]

[Chemical 84]

Next, the liquid crystal compositions 7-BI and 7-BI were used.
A liquid crystal element was produced in the same manner as in Example 1 except that I, 7-BIII was used, and the orientation and optical response showing a uniform shape were measured in the same manner as in Example 1. Further, the contrast ratio at 30 ° C. was also measured. The results are shown below.

Liquid Crystal Composition 7-BI Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal device.

[0318]

[Table 33] Contrast ratio at 30 ° C: 33

Liquid crystal composition 7-BII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal device.

[0320]

[Table 34] Contrast ratio at 30 ° C: 29

Liquid Crystal Composition 7-BIII Alignment showing uniform property (visual observation with a microscope): Uniform uniform alignment was obtained over almost the entire surface of the liquid crystal device.

[0322]

[Table 35] Contrast ratio at 30 ° C: 37

As is clear from Example 7, the liquid crystal compositions 7-BI, 7-BII,
Liquid crystal devices using 7-BIII all showed uniform uniform alignment, but the concentration characteristics were
Liquid crystal composition 7 using 34 and 4-86 respectively
-BI, 7-BII is 4.19,4.28 (f ^10/40)
On the other hand, the liquid crystal composition 7-BIII using both of the exemplified compounds 3-34 and 4-86 has a value of 4.00, which shows that the liquid crystal composition has an appropriate temperature characteristic. Also, it can be seen that the contrast ratio is better when both of them are used at the same time than when they are used alone. further,
The composition 7-BIII also exhibits excellent characteristics in terms of driving voltage margin.

[0324]

As described above, the liquid crystal element using the ferroelectric liquid crystal composition containing the specific liquid crystal compound under the specific element constitution conditions according to the present invention shows good uniform orientation, The temperature dependence of the response speed is reduced and high contrast is achieved in a well-balanced manner. In addition, it exhibits excellent physical properties in terms of driving voltage margin.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a liquid crystal element of the present invention.

FIG. 2 is an explanatory diagram showing C1 and C2 orientations.

FIG. 3 is an explanatory diagram showing a relationship among a tilt angle Θ, a pretilt angle α, and a layer inclination angle δ in C1 and C2 orientations.

FIG. 4 is a timing chart showing driving waveforms applied to the liquid crystal element of FIG.

FIG. 5 is a plan view of a liquid crystal panel in which matrix electrodes are arranged.

FIG. 6 is a block diagram showing a liquid crystal display device and a graphic controller used in the present invention.

FIG. 7 is a timing chart of image information communication between the liquid crystal display device and the graphic controller used in the present invention.

FIG. 8 is a waveform diagram of a driving method related to the present invention.

FIG. 9 is a schematic test plot diagram of a display pattern when actual driving is performed with the time-series driving waveform shown in FIG.

FIG. 10 is a (VT characteristic diagram) graph showing a change in transmittance when a drive voltage is changed.

[Explanation of symbols]

11a, 11b Glass substrate 12a, 12b Transparent electrode 13a, 13b Insulating alignment control layer (insulating film) 14a, 14b Insulating alignment control layer (alignment control film) 15 Liquid crystal layer 16 Spacer 17a, 17b Polarizing plate 21a, 21b Substrate 23 Liquid crystal molecule 24 Dipole moment (P⊥) 31a, 31b Voltage applying means 33a, 33b First stable state of liquid crystal molecule, or
Second stable state 34a, 34b Dipole moment upward or downward 51 liquid crystal panel 52 scanning electrode group 53 information electrode group 101 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 Generation Circuit 108 Shift Register 109 Line Memory 110 Information Signal Generation Circuit 111 Drive Control Circuit 112 GPCU 113 Host CPU 114 VRAM

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G02F 1/1337 510 G02F 1/1337 510 1/141 1/137 510 (72) Inventor Masahiro Terada Tokyo 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Shuji Yamada 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kazunori Katagiri Ota-ku, Tokyo Shimomaruko 3-30-2 Canon Inc.

Claims (22)

[Claims] 1. A liquid crystal composition comprising a compound represented by the following general formulas 1 and 2 as an essential component. General formula 1 R ₁ -A ₁ -X ₁ -A ₂ -X ₂ -A ₃ -R ₂ (wherein R ₁ and R ₂ are a hydrogen atom, a halogen or a CN group; Alternatively, it is a linear, branched, or cyclic alkyl group having 1 to 18 carbon atoms, and one or two or more methylene groups in the alkyl group are -O under the condition that hetero atoms are not adjacent to each other. -, -S-, -CO-, -CHW-, -CH
It may be replaced by ═CH— or —C≡C—, and W represents halogen or CF ₃ . Further, R ₁ and R ₂ may each independently be optically active. Embedded image Alternatively, it is a straight-chain or branched alkyl group having 1 to 18 carbon atoms, and one or two or more methylene groups in the alkyl group may have a structure in which hetero atoms are not adjacent to each other.
O-, -S-, -CO-, -CHW-, -CH = CH
May be replaced by-, -C≡C-, W
Represents halogen and CF ₃ . Further, R ₃ and R ₄ may each independently be optically active. Y ₁ , Y ₂ are H, F, C
1, Br, CH ₃ , CF ₃ or CN, and Z is —O—
Or -S- is shown. However, at least one of A ₁ , A ₂ and A ₃ is General formula 2 R ₅ -A ₄ -R ₆ L is an integer of 3 to 16, R ₇ is a linear, branched, or cyclic alkyl group having 1 to 18 carbon atoms (one or two or more methylene groups in the alkyl group). The group is -O-, -S-, -CO-, -CHW-, -CH = C under the condition that heteroatoms are not adjacent to each other.
H-, -C≡C- may be substituted,
W represents halogen, CN or CF ₃ . ), [Chemical 5] A ₄ is, -A ₅ -X ₅ -A ₆ - or -A ₅ -A ₆ -X ₅ -A ₇
-Indicated. A ₅ , A ₆ and A ₇ are each independently (Y ₉ , Y _9'are each independently H, F, CH ₃ , CF
_It is selected from the _three . ), A ₅ ,
At least one of A ₆ and A ₇ is Is one of. Embedded image 2. The liquid crystal composition according to claim 1, wherein the compound represented by the general formula 1 is a compound represented by the following general formula 3. Formula _{3 R 8 -A 8 -A 9 -A} 10 -R 9 ( in the Formula, R _8, R ₉ represents a linear 1 to 18 carbon atoms, branched, or cyclic alkyl group And one of the alkyl groups, or two or more methylene groups that are not adjacent to each other, is -O-,-
S-, -CO-, -CHW-, -CH = CH-, -C≡
It may be replaced by C-, and W represents a halogen or CF ₃ group. R ₈ and R ₉ may each independently be optically active. A ₈ , A ₉ and A ₁₀ are single bonds, or At least one of A ₈ , A ₉ and A ₁₀ is 3. The liquid crystal composition according to claim 1, wherein the compound represented by the general formula 2 is a compound represented by the following general formula 4. General formula 4 (R ₁₁ and R ₁₂ are hydrogen atoms or 1 to 1 carbon atoms.
8 is a linear, branched or cyclic alkyl group,
One or two or more methylene groups in the alkyl group may be -O-, -S under the condition that hetero atoms are not adjacent to each other.
-, -CO-, -CHW-, -CH = CH-, -C≡C
- may be replaced by, W is a halogen, a CN group, CF ₃ group. In addition, R ₁₁ and R ₁₂ may independently be optically active. However, R ₁₁ ,
One of R ₁₂ is a hydrogen atom. A ₁₁ , A ₁₂ , A
₁₃ , A ₁₄ is a single bond, However, one of A ₁₁ and A ₁₄ is a single bond,
It is not a single bond at the same time, and at least one of A ₁₂ and A ₁₃ is a single bond.
n and m are 0 or an integer of 3-16. However,
One of them is 0 and never 0 at the same time. [Chemical 13] 4. A compound represented by the following general formula (5) is 20 to 75% by weight, a compound represented by the general formula (6) is 5 to 25% by weight, and a compound represented by the general formula (7) is 5% by weight. ~
30% by weight of the compound represented by the general formula (8)
The liquid crystal composition according to claim 1, wherein the liquid crystal composition contains 30% by weight. Embedded image (P and q are 0, 1, and 2, p + q is 1 or 2, Y ₁₀ represents a hydrogen atom or a fluorine atom, R ₂₁ ,
R ₂₂ is a linear or branched alkyl group having 1 to 18 carbon atoms, and one or more methylene groups in the alkyl group are -O-,-under the condition that hetero atoms are not adjacent.
S-, -CO-, -CHW-, -CH = CH-, -C≡
C-may be substituted, W is a halogen atom,
A CN group and a CF ₃ group are shown. Further, R ₂₁ and R ₂₂ may be optically active. ) [Chemical 15] (Y ₀ represents a hydrogen atom or a fluorine atom, Y ₁₁ represents a hydrogen atom or a fluorine atom, and R ₂₃ represents 1 carbon atom.
To 18 are linear or branched alkyl groups, R ₂₄ is a hydrogen atom, a halogen atom, a CN group, or a carbon number of 1 to 1.
8 is a linear or branched alkyl group, and one or more methylene groups in the alkyl groups represented by R ₂₃ and R ₂₄ are —O—, —S under the condition that hetero atoms are not adjacent to each other. -,
-CO-, -CHW-, -CH = CH-, -C≡C-, W may be a halogen atom or CN.
Group and CF ₃ group. R ₂₃ and R ₂₄ may be optically active. ) [Chemical 16] (R ₂₅ and R ₂₆ are linear or branched alkyl groups having 1 to 18 carbon atoms, and one or two or more methylene groups in the alkyl group may have a structure in which hetero atoms are not adjacent to each other.
O-, -S-, -CO-, -CHW-, -CH = CH
-, - C≡C- may be replaced with, W is a halogen atom, CN group, CF ₃ group. Also, R ₂₅ and R ₂₆
May be optically active. ) [Chemical 17] (R ₂₇ and R ₂₈ are linear or branched alkyl groups having 1 to 18 carbon atoms, and one or two or more methylene groups in the alkyl group may be a group represented by the formula:
O-, -S-, -CO-, -CHW-, -CH = CH
-, - C≡C- may be replaced with, W is a halogen atom, CN group, CF ₃ group. Also, R ₂₇ and R ₂₈
May be optically active. ) 5. The compound represented by the general formula (5) is
A compound represented by any of the following general formulas (5-1) to (5-7), wherein the compound represented by the general formula (6) is represented by the following general formulas (6-1) to (6-5). Which is a compound represented by any one of the following general formulas (7-1) to (7-9), and a compound represented by the general formula (8): The liquid crystal composition according to claim 4, wherein the compound represented by is a compound represented by any of the following general formulas (8-1) to (8-6). Embedded image [Chemical 19] Embedded image [Chemical 21] (However, in the formula, R _{21 to} R ₂₈ and Y ₁₁ are represented by the general formula (5) to
Same as shown in (8). ) 6. The liquid crystal composition according to claim 1, which contains at least one or more optically active compounds. 7. The liquid crystal composition according to claim 1, which exhibits at least a chiral smectic phase. 8. The liquid crystal composition according to claim 7, which exhibits ferroelectricity. 9. The liquid crystal composition according to claim 7, which is a liquid crystal composition exhibiting a cholesteric phase, a smectic phase, and a chiral smectic phase in a temperature lowering process from an isotropic liquid phase. 10. The liquid crystal composition according to claim 7, wherein the chiral smectic phase is a chiral smectic C phase. 11. The liquid crystal composition according to claim 1, which comprises 1 to 40% by weight of the compounds represented by the general formulas (1) and (2), respectively. 12. The liquid crystal composition according to claim 1, which comprises 1 to 30% by weight of each of the compounds represented by the general formulas (1) and (2). 13. The liquid crystal composition according to claim 1, which comprises 1 to 20% by weight of each of the compounds represented by the general formulas (1) and (2). 14. A chiral smectic C phase layer having an inclination angle δ of 3 ° or more and 15 ° or more in a temperature range of 0 ° C. to 60 ° C.
The liquid crystal composition according to claim 10, which is adjusted below. 15. A liquid crystal element comprising: a liquid crystal; and a pair of substrates facing each other with the liquid crystal sandwiched therebetween, and a pair of substrates having electrodes for applying a voltage to the liquid crystal formed on the facing surfaces, wherein at least one substrate. The alignment control layer for controlling the alignment state of the liquid crystal is provided on the opposite surface side of the liquid crystal.
14. A liquid crystal device, which is the liquid crystal composition according to any one of 14 above. 16. When the liquid crystal composition is a chiral smectic liquid crystal, and the pretilt angle of the device is α, the tilt angle of the liquid crystal is Θ, and the tilt angle of the liquid crystal layer is δ, the chiral smectic liquid crystal is at least It has an orientation state represented by the following formulas (I) and (II) near room temperature, and exhibits at least two stable states in this orientation state, and is 1/2 of the angle formed by the optical axes thereof. 16. The liquid crystal device according to claim 15, wherein the apparent tilt angle θ _a and the tilt angle θ have the relationship of the following formula (III). Θ <α + δ (I) δ <α (II) Θ> θ _a > Θ / 2 (III) 17. An alignment control layer for controlling the alignment state of liquid crystal is provided on each of the facing surfaces of the both substrates, and each of the alignment control layers is subjected to a uniaxial alignment treatment. 16. The liquid crystal element according to claim 15, wherein are substantially parallel to each other. 18. An alignment control layer for controlling the alignment state of liquid crystals is provided on each of the opposing surfaces of both substrates, and each of the alignment control layers is subjected to a uniaxial alignment treatment, and the uniaxial alignment treatment axis has a predetermined axis. 16. The liquid crystal element according to claim 15, which intersects at an angle of. 19. The intersecting angle of the uniaxial orientation treatment axes is 25 °.
The liquid crystal element according to claim 18, which is as follows. 20. The size of the pretilt angle α is 5
17. The liquid crystal device according to claim 16, wherein the liquid crystal device has an angle of at least °. 21. The liquid crystal device according to claim 16, wherein the pair of substrates sandwiching the liquid crystal face each other at a distance between the substrates that releases a helical molecular arrangement peculiar to the liquid crystal. 22. A liquid crystal device comprising the liquid crystal element according to claim 15 and a drive circuit for the liquid crystal element.