JPH1046148A - Liquid crystal element and liquid crystal device made by using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid crystal element which can realize high-reliability switching elements and light bulb elements by sandwiching a liquid crystal between a pair of bases each of which has an electrode and forming a layer mainly made of a racemic modification compound on at least one of the bases. SOLUTION: This element is prepared by sandwiching a liquid crystal 1 between a pair of bases 2a and 2b having transparent electrodes 3a and 3b, respectively, and forming at least one of layers 7a and 7b mainly made of a racemic modification compound on at least one of the bases 2a and 2b. In this element, it is desirable that at least one of liquid crystal alignment control layers 4a and 4b is formed on at least one of the bases 2a and 2b, and a layer 7a or layers 7a and 7b mainly made of the racemic modification compound is (are) formed between the layer 4a (or 4b) and the layer 1. This element has markedly improved switching characteristics and can give high-contrast and high-reliability switching elements and light bulb elements. Therefore, it can realize a liquid crystal device having high performances including high grade and high image quality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal device used for a light valve used in a flat panel display, a projection display, a printer, and the like.

[0002]

2. Description of the Related Art A CRT is known as a display which has been most widely used in the past, and is used as a moving image output for televisions and VTRs or a monitor for personal computers. However, recently, it has been found that the electromagnetic waves generated by the CRT have an adverse effect on the human body, and there is a concern that the health of VDT workers may be impaired. In addition, since the CRT is required to have a large volume behind the screen due to its structure, there is a problem that the convenience of the information device is significantly impaired and the space saving of offices and homes is impeded. .

As a solution to such a disadvantage of the CRT, there is a liquid crystal display element. For example, Applied Physics Let by M. Schadt and W. Helfrich.
ters), Vol. 18, No. 4 (published on Feb. 15, 1971), pp. 127-128, using a twisted nematic liquid crystal is known. A simple matrix type liquid crystal element is known as a typical liquid crystal element. This type has an advantage in that the element can be easily formed and the cost is low. However, in the case of time-division driving using a matrix electrode structure with a high pixel density, there is a problem that crosstalk occurs, so that the number of pixels has been limited.

In recent years, a liquid crystal element called a TFT has been developed for such a simple matrix type element. In this type, a transistor is created for each pixel, which solves the problems of crosstalk and response speed, but the larger the area, the more difficult it is to make a liquid crystal element without defective pixels. is there.

As an improvement over such a conventional liquid crystal element, a liquid crystal element having bistability is provided by Clark (Cl.
ark) and Lagerwall (JP-A-56-107216, U.S. Pat. No. 4,367,924, etc.). In general, a ferroelectric liquid crystal exhibiting a chiral smectic C phase or a chiral smectic H phase is used as the liquid crystal having the bistability. Since the ferroelectric liquid crystal performs inversion switching by spontaneous polarization, it has a very fast response speed and can exhibit bistability with memory properties. Further, since the viewing angle characteristics are also excellent, it is considered that they are suitable as a high-speed, high-definition, large-area display element or a light valve. Recently, a chiral smectic antiferroelectric liquid crystal device having three stable states has been proposed by Chandani, Takezoe et al. (Japanese Journal of Applied Physics).
Applied Physics, Vol. 27, 1988
Year, p. 729).

Further, there is a movement to realize a layered structure called a bookshelf or a structure similar thereto and realize a high-contrast good liquid crystal element (for example, "Next-generation liquid crystal display and liquid crystal material", CMC Co., Ltd. Atsuo Fukuda, 1992). In addition, a liquid crystal compound having a perfluoroether side chain (US Pat. No. 5,262,082, International Patent Application WO 93/22) as a liquid crystal material exhibiting a bookshelf or a structure similar thereto.
396, 1993 4th International Conference on Ferroelectric Liquid Crystal P-4
6, Marc D. Radcliffe et al.).

[0007]

A line-sequential driving method is effective as a driving method for a liquid crystal element having a memory property using a ferroelectric liquid crystal exhibiting a chiral smectic phase as described above. In this driving method, for example, in a simple matrix element having 1000 scanning lines, only an information signal is applied for 25 ms at a writing frequency of 40 Hz and 50 ms at a writing frequency of 20 Hz (time required for one screen writing). At this time, the liquid crystal is in a state of being fluctuated by the information signal, and this fluctuation causes light leakage in a black state of the liquid crystal element, and there is a problem that the contrast is reduced or flicker occurs.

An object of the present invention is to provide a liquid crystal device which can solve the above problems, realize a highly reliable switching device and light valve device, and have excellent performance such as high quality and high image quality. And

[0009]

The invention according to claims 1 to 13 is a liquid crystal element in which a liquid crystal is sandwiched between a pair of substrates each having an electrode, wherein at least one of the substrates contains a racemic compound as a main component. A liquid crystal device characterized by having a layer as follows. The invention according to claim 14 is a liquid crystal device comprising the liquid crystal device and driving means for the liquid crystal device.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic sectional view showing an example of the liquid crystal element of the present invention. In the figure, reference numeral 1 denotes a liquid crystal layer. 2a, 2
b is an upper and lower substrate made of glass or the like, and each substrate is provided with a transparent electrode 3a, 3b of, for example, tin oxide, indium tin oxide (ITO) or the like.

Reference numerals 4a and 4b denote orientation control layers, which are made of a general organic insulating material or inorganic insulating material, for example, a polyimide, preferably an aliphatic polyimide, and a polyimide having the following structural unit has good orientation. Are preferably used in that they give

[0013]

Embedded image In an element having a structure in which different alignment control layers are provided on both substrates, it is preferable to provide one of the substrates obtained by subjecting the polyimide to a uniaxial alignment treatment (rubbing treatment). In particular, when a chiral smectic liquid crystal that does not exhibit a cholesteric phase is used as the liquid crystal composition, a layer made of polyimide and subjected to a uniaxial alignment treatment is formed on one of the substrates,
A surface energy of 30 dyne / cm ² on the other substrate side
It is preferable to use the following film which has not been subjected to an orientation treatment because the uniformity of the orientation can be ensured. As a material of the film not subjected to the alignment treatment, a silane coupling agent, a fluorine-based organic polymer, a mixed film of a silicone polymer binder and conductive fine particles, or the like can be used.

The measurement of the surface energy based on the macro surface state of each substrate of the liquid crystal element will be described. As the reagent for the contact angle of the droplet, for example, A: α-bromonaphthalene, B: methylene iodide, C: water and the like are used. Then, after measuring the contact angle by each of A, B, C, etc., for example, Journal of the Adhesion Society of Japan, Vol. 8, No. 3 (1972) p131
Kitazaki et al. Can be obtained by the calculation formula described in "Expansion of Fowkes equation and evaluation of surface tension of polymer solid".

The transparent electrodes 3a, 3b and the orientation control layers 4a, 4
b, an intermediate layer 5a, such as a short prevention layer,
5b can also be provided.

Reference numeral 6 denotes a gap control spacer, for example, silica beads or the like can be used.

Reference numerals 7a and 7b are interface layers containing a racemic compound as a main component. As a compound forming the interface layers 7a and 7b, for example, a compound represented by the following general formula can be used.

[0018]

Embedded image

These racemic compounds are used to form the interface layers 7a and 7b.
Can be formed by dissolving it in a solvent and applying it, or by depositing liquid crystal. However, any other method can be used as long as it can form a thin film layer.

In FIG. 1, interface layers 7a and 7b are provided at both interfaces.
The interface layer may be provided on at least one of the upper and lower substrates. When one of the upper and lower substrates has an orientation control layer subjected to a uniaxial orientation treatment, and the other has an orientation control layer not subjected to a uniaxial orientation treatment, the uniaxial orientation treatment is not applied. It is desirable to provide an interface layer on the orientation control layer.

As the liquid crystal layer 1, a liquid crystal or the like exhibiting a chiral smectic phase and exhibiting ferroelectricity is used.
The ferroelectric liquid crystal preferably used in the present invention is composed of a chiral smectic C phase or a chiral smectic H phase, and particularly preferably a chiral smectic liquid crystal having a layer structure close to a bookshelf and having a small layer tilt angle is excellent in driving. It is desirable in that it has characteristics. When a liquid crystal material which does not take a cholesteric (Ch) phase is used as such a liquid crystal material, a liquid crystal element provided with an alignment control layer that has been subjected to a uniaxial alignment treatment on only one of the above-described substrates is applied to improve the alignment state of the liquid crystal. Is preferred.

The chiral smectic liquid crystal composition which does not exhibit a Ch phase used in the present invention preferably has a fluorocarbon terminal portion and a hydrocarbon terminal portion, and both terminal portions are bound by a central nucleus to form a smectic intermediate phase or latent liquid. It is desirable to contain a fluorine-containing liquid crystal compound having a typical smectic mesophase.

In the present invention, the fluorine-containing liquid crystal compound preferably has a fluorocarbon terminal moiety of -D
¹ -C _xa F _2xa -X group represented by, (wherein, the formula xa is 1 to 20, X represents -H or -F, D
_{^1, -CO-O- (CH 2)} ra -, - O- (CH 2)
_{ra -, - (CH 2)} ra -, - O-SO 2 -, - SO 2
_{-, - SO 2 - (CH} 2) ra -, - O- (CH 2) ra -
_{O- (CH 2) rb -,} - (CH 2) ra -N (C pa H
_2pa + 1) -SO ₂ -, or _{- (CH 2) ra -N (} C pa H
_{2pa + 1} ) represents -CO-. ra and rb are independently 1
-20 and pa is 0-4. ) Or -D
^2- (C _xb F _2xb -O) _za -C _ya F _{2ya + 1} , wherein xb is each of (C _xb F _2xb −
O) independently is 1 to 10, ya is 1 to 10, za is 1 to 10, D ² are, -CO-O-C _{rc
H 2rc -, - O-C} rc H 2rc -, - C rc H 2rc -, - O
-(C _sa H _2sa -O) _ta -C _rd H _2rd- , -O-SO _{2
-, - SO 2 -, -} SO 2 -C rc H 2rc -, - C rc H
_{2rc -N (C pb H 2pb +} 1) -SO 2 -, - C rc H 2rc -
_{Selected from} N (C _pb H _{2pb + 1} ) —CO— and a single bond;
And rd are independently 1 to 20, sa is independently 1 to 10 for each (C _sa H _2sa -O), and ta is 1
And pb is 0-4. ) Can be used.

Particularly preferably, a fluorine-containing liquid crystal compound represented by the following general formula (I) or (II) can be used.

[0025]

Embedded image Represents

Ga, ha, and ia each independently represent an integer of 0 to 3 (provided that ga + ha + ia is at least 2).

Each of L ¹ and L ² is independently a single bond, -C
O-O-, -O-CO-, -COS-, -S-CO-,
-CO-Se-, -Se-CO-, -CO-Te-,-
_{Te-CO -, - CH 2} CH 2 -, - CH = CH -, -
C≡C -, - CH = N - , - N = CH -, - CH 2 -O
_{-, - O-CH 2 -} , - CO- or represent -O-.

Each of X ¹ , Y ¹ , and Z ¹ is A ¹ , A ² , A
³ , independently of -H, -Cl, -F, -B
r, -I, represent _{-OH, -OCH 3, -CH 3,} -CN, or -NO _2, each of ja, ma, na are independently an integer of 0-4.

J ¹ is -CO-O- (CH ₂ ) _ra -,-
_{O- (CH 2) ra -,} - (CH 2) ra -, - O-SO 2
_{-, - SO 2 -, -} SO 2 - (CH 2) ra -, - O-
(CH ₂ ) _ra -O- (CH ₂ ) _rb -,-(CH ₂ ) _{ra-
N (C pa H 2pa + 1} ) -SO 2 -, or - (CH _{2) ra} -
_{N (C pa H 2pa + 1} ) represents the -CO-. ra and rb
Is independently 1 to 20, and pa is 0 to 4.

R ¹ is _{-OC qa} H _{2qa -OC qb} H
_{2qb + 1, -C qa H 2qa} -O-C qb H 2qb + 1, -C qa H
_{^{2qa -R 3, -O-C qa}} H 2qa -R 3, -CO-O-C
_qa H _2qa -R ^3, or represents _{-O-CO-C qa H 2qa} -R 3, linear, may be either branched (wherein, R ³ is, -O-CO-C _qb H _{2qb + 1} , -CO-O-
_{C qb H 2qb + 1, -H} , -Cl, -F, -CF 3, -NO
₂ , -CN, and qa and qb are independently 1-20).

R ² represents C _xa F _2xa -X (X is -H
Or -F, and xa is an integer of 1 to 20).

[0032]

Embedded image Represents

Gb, hb and ib are each independently 0 to 3
(Where gb + hb + ib is at least 2).

Each of L ³ and L ⁴ is independently a single bond, -C
O-O-, -O-CO-, -CO-S-, -S-CO
-, -CO-Se-, -Se-CO-, -CO-Te
-, - Te-CO -, - (CH 2 CH 2) ka - (ka is 1~4), - CH = CH - , - C≡C -, - CH = N
-, - N = CH -, - CH 2 -O -, - O-CH 2 -,
Represents -CO- or -O-.

Each of X ² , Y ² , and Z ² is A ⁴ , A ⁵ , A
⁶ is independently -H, -Cl, -F, -B
_{r, -I, -OH, -OCH 3} , -CH 3, -CF 3,
—OCF ₃ , —CN, or —NO ₂ , each j
b, mb, and nb independently represent an integer of 0 to 4.

J ² is —CO—O—C _rc H _2rc —, _{—O
-C rc H 2rc -, - C} rc H 2rc -, - O- (C sa H 2sa
_{-O) ta -C rd H 2rd -} , - OSO 2 -, - SO 2 -,
_{-SO 2 -C rc H 2rc -,} - C rc H 2rc -N (C pb H
_{2pb + 1) -SO 2 -,} - C rc H 2rc -N (C pb H
_{2pb + 1} ) -CO-, wherein rc and rd are independently 1-2.
0, sa is independently 1 to 10 for each (C _sa H _2sa -O), ta is 1 to 6, pb is 0 to 4
It is.

[0037] R ⁴ _{is, -O- (C qc H 2qc -O} ) wa -C
_{qd H 2qd + 1, - (} C qc H 2qc -O) wa -C qd H 2qd + 1,
^{_{-C qc H 2qc -R 6, -O}} -C qc H 2qc -R 6, -CO
^{_{-O-C qc H 2qc -R 6}} , or _{-O-CO-C qc} H 2qc
It represents -R ^6, linear, may be either branched (wherein, R ⁶ is _{-O-CO-C qd H 2qd} + 1, -CO-
_{O-C qd H 2qd + 1} , -Cl, -F, -CF 3, -NO
₂ , -CN, or -H, qc and qd are each independently an integer of 1 to 20, and wa is an integer of 1 to 10).

R ⁵ is (C _xb F _2xb -O) _za -C _ya F
_{2ya + 1} is represented by (wherein, the formula xb is 1 to 10 independently of each _{(C xb F 2xb -O),} ya is 1
And za is 1-10).

The compound represented by the above general formula (I)
JP-A-2-142755, U.S. Pat.
2,587.
Specific examples of such compounds are listed below.

[0040]

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[0041]

Embedded image

[0042]

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[0043]

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[0044]

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[0045]

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[0046]

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[0047]

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[0048]

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[0049]

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[0050]

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[0051]

Embedded image

The compound represented by the above general formula (II) is described in WO 93/22396, JP-T-Hei 7-506.
368 can be obtained.
Specific examples of such compounds are listed below.

[0053]

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[0054]

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[0055]

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[0056]

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[0057]

Embedded image

These liquid crystal compositions contain one or more optically active compounds (chiral dopants) having at least one asymmetric carbon.

Further, specific examples of the chiral compound include those having the following structures, but the present invention is not limited thereto.

[0060]

[Table 1]

[0061]

[Table 2]

[0062]

[Table 3]

[0063]

[Table 4]

[0064]

[Table 5]

[0065]

[0066]

Embedded image

[0067]

Embedded image

[0068]

Embedded image

[0069]

Embedded image

[0070]

Embedded image

[0071]

Embedded image n = 1, 2, 3, 4, 6

[0072]

Embedded image n = 1, 2, 3, 4, 6, 10

[0073]

Embedded image n = 8,10

[0074]

Embedded image

[0075]

Embedded image

[0076]

Embedded image

[0077]

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In the liquid crystal composition, optimal conditions are set between a pair of substrates (at least one of which has the interface layer containing a racemic compound as a main component) so as to reduce the deterioration of the racemic compound. And is arranged by injection or the like.

The liquid crystal element of the present invention constitutes a liquid crystal device having various functions. For example, when the liquid crystal element of the present invention is used in a display panel, a data format of image information having scanning line address information shown in FIGS.
A liquid crystal display device is realized by using communication synchronization means using the C signal.

The image information is generated by the graphic controller 102 on the main unit side, and is transferred to the display panel 103 according to the signal transfer means shown in FIGS. The graphics controller 102 has a CP
U (central processing unit, hereinafter abbreviated as GCPU 112) and VRAM (memory for storing image information) 114 serve as a nucleus for managing and communicating image information between the host CPU 113 and the liquid crystal display device 101. The method is mainly realized on the graphics controller 102.

The reference numerals in the figure are as follows.

101 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 111 Drive control circuit 112 GCPU 113 Host CPU 114 VRAM

The driving method of the liquid crystal element of the present invention is described in, for example, JP-A-59-193426 and JP-A-59-19193.
The driving method disclosed in Japanese Patent No. 3427, Japanese Patent Application Laid-Open No. 60-156046, Japanese Patent Application Laid-Open No. 60-156047 or the like can be applied.

FIG. 4 is a waveform chart showing an example of the driving method.
FIG. 6 is a plan view showing an example of a ferroelectric liquid crystal panel on which matrix electrodes are arranged. The liquid crystal panel 91 of FIG.
The scanning lines of the scanning electrode group 92 and the data lines of the information electrode group 93 are wired so as to cross each other, and a ferroelectric liquid crystal is disposed between the scanning line and the data line at the intersection. I have.

In FIG. 4A, S _S applies a selected scanning waveform to be applied to a selected scanning line, S _N applies an unselected scanning waveform which is not selected, and I _S applies to a selected data line. In the selection information waveform (black), _IN indicates a non-selection information signal (white) applied to the unselected data line. Also,
In Figure and (I _S -S _S) in (I _N -S _S) is waveforms applied to pixels on a selected scanning line, a pixel voltage (I _S -S _S) is applied becomes a black display state , Voltage (I _N -S
_The pixel to which _S ) is applied becomes a white display state.

FIG. 4B shows the driving waveform shown in FIG. 4A, which is a time-lapse waveform when the display shown in FIG. 5 is performed.

In the driving example shown in FIG. 4, the minimum application time Δt of the unipolar voltage applied to the pixels on the selected scanning line corresponds to the time of the writing phase t ₂ , and one line clear t ₁
The phase time is set to 2 △ t.

The values of the parameters V _S , V _R , and Δt of the drive waveform shown in FIG. 4 are determined by the switching characteristics of the liquid crystal material used.

FIG. 7 shows the transmittance T when the drive voltage (V _S + V ₁ ) is changed while the bias ratio described later is kept constant.
, Ie, the VT characteristic. Here, Δt = 50 μsec, and the bias ratio V _I / (V _I + V
_S ) = 1/3 is fixed. The positive side of Fig. 7 is shown in FIG. 4 (I _N -S _S), the negative side (I _S -S _S) at the indicated waveform when applied (V _S + V _I) final transmission The relationship of the rate T is shown. The positive side indicates a case where the previous state is black, the reset direction is white, and the negative side indicates a case where the previous state is white and the reset direction is black.

Here, V ₁ and V ₃ are called an actual drive threshold voltage and a crosstalk voltage, respectively. Also, V ₂ <V ₁ <
When △ V = V ₃ a -V ₁ is called a voltage margin matrix drivable voltage range of V ₃ becomes. It can be said that V ₃ generally exists in driving the ferroelectric liquid crystal display element. Specifically a voltage value causing switching by V _B in the waveform of FIG. _{4 (A) (I N -S} S). Of course, by increasing the bias ratio, it is possible to increase the value of V _3, increasing the bias ratio corresponds to a large amplitude of a data signal, an increase in flickering in image quality, This leads to a decrease in contrast, which is not preferable.

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

Similarly, the above-mentioned voltage is kept constant,
Driving can be performed by changing the voltage application time Δt. The above-mentioned voltage may be used as the voltage application time as it is, and in this case, the voltage application time threshold is set to Δt ₁
And the voltage application time crosstalk value is Δt ₂ , (△
t ₂ −Δt ₁ ) = ΔT is called a voltage application time margin.

At a certain constant temperature, two states of black and white can be written to the selected pixel depending on the two directions of the information signal, and the non-selected pixels maintain the black or white state. The voltage margin or voltage application time margin that can be obtained differs depending on the liquid crystal material and the element configuration, and is unique. In addition, since the drive margins are different depending on the change in the environmental temperature, in the case of an actual display device, it is necessary to set optimal drive conditions for the liquid crystal material, the element configuration, and the environmental temperature.

In the display device which is an example of the liquid crystal device of the present invention, good contrast characteristics can be obtained because the optical fluctuation of the switching element as the display medium is reduced.

[0095]

【Example】

[Example 1] The cell used in this example was manufactured as follows.

After forming an ITO film on one glass substrate, the NM of a polyimide (precursor) having the following structural unit was obtained.
A 0.5% by weight solution of P / nBC = 2/1 was spin-coated and baked to obtain a 5-nm polyimide coating film. The coating film thus formed was subjected to a rubbing treatment with a nylon cloth to obtain a uniaxially oriented film.

[0097]

Embedded image

After forming an ITO film on the other glass substrate, a silane coupling agent (octadecyltriethoxysilane) solution was applied and dried at 80 ° C. Next, a racemic compound solution in which silica bead spacers are dispersed (IPA: silica bead spacer: the following racemic compound A = 100: 0.02: 0.1) is spin-coated,
Dried at 80 ° C.

[0099]

Embedded image

The above two substrates were bonded together, and the gap was 1.8.
A μm cell was prepared. After injecting a composition containing the following fluorine-containing liquid crystal compound into this cell, 0.1 ° C./min.
At a cooling rate of The apparent tilt angle is 27 °.

[0101]

Embedded image A: B ₁ : B ₂ : B ₃ : C = 80: 3: 3: 4: 5

The contrast was measured by interposing the element between polarizing plates arranged in crossed Nicols, and the driving waveform (2) shown in FIG.
0 V / μm, 1/3 bias, 1000 duty (m = 10 in Sm of the matrix structure shown in FIG. 6)
00)). Next, the pulse width is changed, and the element is rotated to an angle at which the darkest transmitted light intensity at the time of driving can be obtained with the pulse width of the threshold value of the black and white complete inversion. The transmitted light intensity Iw when the molecule was inverted was detected using a photomultiplier, and the ratio (Iw / Ib) was defined as the contrast (CR). CR was 90.

Example 2 A cell was prepared in the same manner as in Example 1 except that the racemic compound A was changed to the following racemic compound B, and the same evaluation was performed. As a result, the contrast (CR) was 85.

[0104]

Embedded image

Comparative Example 1 A cell was prepared in the same manner as in Example 1 except that the racemic compound A was not applied, and the same evaluation was performed. As a result, the contrast (CR) was 54.

Comparative Example 2 A cell was prepared in the same manner as in Example 1 except that 1%, 5% and 10% were added to the liquid crystal mixture without applying the racemic compound A, and the same evaluation was performed. As a result, the contrast (CR) is 48, 52, respectively.
53.

[0107]

As described above, according to the present invention, the switching of the liquid crystal element can be remarkably improved.
A switching element and a light valve element having high contrast and high reliability can be obtained, and a liquid crystal device having excellent performance such as high quality and high image quality can be realized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment of a liquid crystal element of the present invention.

FIG. 2 is a block diagram illustrating a display device including a liquid crystal element of the present invention and a graphics controller.

FIG. 3 is a diagram showing a timing chart of image information communication between a display device and a graphics controller.

FIG. 4 is a diagram showing an example of a driving waveform used for driving the liquid crystal element of the present invention.

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

FIG. 6 is a plan view of a liquid crystal panel on which matrix electrodes are arranged.

FIG. 7 is a VT characteristic diagram showing a change in transmittance T when a drive voltage V is changed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal layer 2a, 2b Substrate 3a, 3b Transparent electrode 4a, 4b Alignment control layer 5a, 5b Intermediate layer 6 Spacer 7a, 7b Interface layer containing racemic compound as a main component

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shuji Yamada 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Makoto Mori 3-30-2 Shimomaruko, Ota-ku, Tokyo Kia Within Non Corporation (72) Inventor Shinichi Nakamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Koji Noguchi 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (14)

[Claims] 1. A liquid crystal element in which liquid crystal is sandwiched between a pair of substrates each having an electrode, wherein at least one of the substrates has a layer containing a racemic compound as a main component. 2. The method according to claim 1, wherein at least one of the substrates has a liquid crystal alignment control layer, and a layer containing the racemic compound as a main component is provided between the alignment control layer and the liquid crystal layer. Liquid crystal element. 3. The liquid crystal device according to claim 1, wherein one of the substrates has an alignment control layer that has been subjected to a uniaxial alignment treatment, and the other substrate has an alignment control layer that has not been subjected to a uniaxial alignment treatment. 4. The liquid crystal device according to claim 3, wherein a layer containing the racemic compound as a main component is provided on the alignment control layer that has not been subjected to the uniaxial alignment treatment. 5. The liquid crystal device according to claim 3, wherein the uniaxial alignment treatment is a rubbing treatment. 6. The liquid crystal device according to claim 1, wherein the liquid crystal is a smectic liquid crystal. 7. The liquid crystal device according to claim 1, wherein the liquid crystal exhibits a chiral smectic phase. 8. The liquid crystal device according to claim 7, wherein the liquid crystal does not show a cholesteric phase. 9. The liquid crystal composition exhibiting a chiral smectic phase has a fluorocarbon terminal portion and a hydrocarbon terminal portion, and both terminal portions are bound by a central nucleus, and has a smectic intermediate phase or a potential smectic intermediate phase. The liquid crystal device according to claim 7, comprising a fluorine-containing liquid crystal compound. 10. The liquid crystal device according to claim 9, wherein the terminal portion of the fluorocarbon in the fluorine-containing liquid crystal compound is a group represented by -D ¹ -C _xa F _2xa -X. (However,
The formula xa is 1 to 20, X represents -H or -F, D ¹ _{is, -CO-O- (CH 2)} ra -, - O-
_{(CH 2) ra -, -} (CH 2) ra -, - O-SO 2 -,
_{-SO 2 -, - SO 2 -} (CH 2) ra -, - O- (CH
_{2) ra -O- (CH 2)} rb -, - (CH 2) ra -N (C
_pa H _{2pa + 1} ) -SO _{2- or-} (CH ₂ ) _ra -N (C
_pa H _{2pa + 1} ) -CO-. ra and rb are independently 1-20, and pa is 0-4. ) 11. The fluorocarbon terminal in the fluorine-containing liquid crystal compound is -D ^2- (C _xb F _{2xb-
O) za -C ya F 2ya +} 1 liquid crystal device according to claim 9, wherein the group represented by. (Where xb in the above formula is (C
_xb F _2xb -O) is independently 1 to 10, and ya is 1 to
10, za is 1 to 10, and D ² is -CO-
_{O-C rc H 2rc -,} - O-C rc H 2rc -, - C rc H 2rc
_{-, - O- (C sa H} 2sa -O) ta -C rd H 2rd -, - O
_{-SO 2 -, - SO 2 -} , - SO 2 -C rc H 2rc -, -
_{C rc H 2rc -N (C pb} H 2pb + 1) -SO 2 -, - C rc H
_{2rc -N (C pb H 2pb +} 1) -CO-, selected from a single bond, rc and rd are 20 independently, sa is 1 independently each (C _sa H _2sa -O) 10 and t
a is 1 to 6, and pb is 0 to 4. ) 12. The liquid crystal device according to claim 9, wherein the fluorine-containing liquid crystal compound is represented by the following general formula (I). Embedded image Represents ga, ha, and ia each independently represent an integer of 0 to 3 (provided that ga + ha + ia is at least 2). L ¹ and L ² are each independently a single bond, —CO—O
-, -O-CO-, -COS-, -S-CO-, -CO
-Se-, -Se-CO-, -CO-Te-, -Te-
_{CO -, - CH 2 CH 2} -, - CH = CH -, - C≡C
-, - CH = N -, - N = CH -, - CH 2 -O -, -
O-CH ₂ -, - CO- or represent -O-. Each X
¹ , Y ¹ and Z ¹ are substituents of A ¹ , A ² and A ³ and independently represent —H, —Cl, —F, —Br, —I, —OH, —O
Represents CH ₃ , —CH ₃ , —CN, or —NO ₂ , and each ja, ma, and na independently represents an integer of 0 to 4.
J ¹ _{is, -CO-O- (CH 2)} ra -, - O- (CH
_{2) ra -, - (CH} 2) ra -, - O-SO 2 -, - SO
_{2 -, - SO 2 - (} CH 2) ra -, - O- (CH 2) ra
_{-O- (CH 2) rb -,} - (CH 2) ra -N (C pa H
_2pa + 1) -SO ₂ -, or _{- (CH 2) ra -N (} C pa H
_{2pa + 1} ) represents -CO-. ra and rb are independently 1
-20 and pa is 0-4. R ¹ is —OC
_qa H _{2qa -OC qb} H _{2qb + 1} , -C _qa H _{2qa -OC qb}
H _{2q b + 1} , -C _qa H _2qa -R ³ , _{-OC qa} H _2qa -R
_{^{3, -CO-O-C qa}} H 2qa -R 3, or -O-CO-
Represents _{C qa} H 2qa -R ^3, linear, may be either branched (wherein, R ³ is, -O-CO-C _qb H
_{2qb + 1, -CO-O-} C qb H 2qb + 1, -H, -Cl, -
F, —CF ₃ , —NO ₂ , and —CN, and qa and q
b is independently 1 to 20). R ² represents a C _xa F _2xa -X (X represents -H or -F, xa is an integer of 1 to 20). ] 13. The liquid crystal device according to claim 9, wherein the fluorine-containing liquid crystal compound is represented by the following general formula (II). Embedded image Represents gb, hb, and ib are each independently an integer of 0 to 3 (however, gb + hb + ib is at least 2)
Represents Each of L ³ and L ⁴ is independently a single bond, -CO
-O-, -O-CO-, -CO-S-, -S-CO-,
-CO-Se-, -Se-CO-, -CO-Te-,-
Te-CO -, - (CH 2 CH 2) ka - (ka is 1
4), -CH = CH-, -C≡C-, -CH = N-,-
_{N = CH -, - CH 2} -O -, - O-CH 2 -, - CO
-Or -O-. Each of X ² , Y ² and Z ² is A
⁴ , A ⁵ , and A ⁶ , each independently being -H, -Cl,
-F, -Br, -I, -OH, -OCH 3, -CH 3,
Represents —CF ₃ , —OCF ₃ , —CN, or —NO ₂ , and each jb, mb, nb independently represents an integer of 0 to 4. J ² is —CO—O—C _rc H _2rc —, _—O —C _{rc
H 2rc -, - C rc H} 2rc -, - O- (C sa H 2sa -O)
_{ta -C rd H 2rd -, -} OSO 2 -, - SO 2 -, - SO
_{2 -C rc H 2rc -, -} C rc H 2rc -N (C pb H 2pb + 1)
_{-SO 2 -, - C rc H} 2rc -N (C pb H 2pb + 1) -CO
And rc and rd are independently 1 to 20, sa
Is independently 1 to 10 for each (C _sa H _2sa -O), ta is 1 to 6, and pb is 0 to 4. R ⁴
_{Is, -O- (C qc H 2qc -O} ) wa -C qd H 2qd + 1, -
_{(C qc H 2qc -O) wa} -C qd H 2qd + 1, -C qc H 2qc -
_{^{R 6, -O-C qc H}} 2qc -R 6, -CO-O-C qc H
_2qc -R ^6, or represents _{-O-CO-C qc H 2qc} -R 6, linear, may be either branched (Here, R
⁶ is _{-O-CO-C qd H 2qd} + 1, -CO-O-C qd H
_{2qd + 1, -Cl, -F,} -CF 3, -NO 2, -CN,
Or -H, qc and qd are each independently an integer of 1 to 20, and wa is an integer of 1 to 10). R ⁵ is (C _xb F
_{2xb -O) za -C ya F 2ya} + 1 is represented by (wherein, the formula xb is each (C _xb F _2xb -O) 1~ independently
10, ya is 1 to 10, and za is 1 to 10). ] 14. A liquid crystal device comprising: the liquid crystal element according to claim 1; and driving means for driving the liquid crystal element.