JPH0959627A - Liquid crystal composition, liquid crystal element and liquid crystal device - Google Patents

Abstract

(57) Abstract: In a liquid crystal element using a chiral smectic liquid crystal, a structure with a small booklet shelf angle or a layer inclination angle is developed to realize a high-brightness liquid crystal element, which has high reliability and is left alone. Get stability. An orientation control layer made of polyimide is provided on at least one substrate, and a specific fluorine having a fluorocarbon terminal portion and a hydrocarbon terminal portion as a chiral smectic liquid crystal and having a chain ether oxygen in the fluorocarbon terminal chain. The contained liquid crystal compound and the non-liquid crystal perfluoro compound are used in combination.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art A CRT is known as the most widely used display. CRT
Is widely used as a moving image output for televisions and VTRs, or as a monitor for personal computers. However,
Due to the characteristics of the CRT, the visibility of a still image may be reduced due to flicker or scanning fringes due to insufficient resolution, or the phosphor may be deteriorated due to burn-in. In addition, recently, it has been found that the electromagnetic waves generated by the CRT adversely affect the human body, which may impair the health of the VDT worker.
Further, because of the large volume behind the screen in terms of structure, space saving in offices and homes may be hindered, and it may not be possible to fulfill the responsibility as a display in an advanced information society.

As a solution to such a disadvantage of the CRT, there is a liquid crystal display element. For example, M. Shut (M.
Schadt) and W. Helfrich (W. He)
Lfrich) "Applied Physics Letters"
s ") Volume 18, Issue 4 (issued February 15, 1971)
Twisted shown on pages 127-128
A liquid crystal device using a nematic (twisted nematic) liquid crystal is known. One is a simple matrix type liquid crystal element, which has a cost advantage. This liquid crystal element has a problem that crosstalk occurs in time-division driving using a matrix electrode structure with a high pixel density, so that the number of pixels is limited. Moreover, since the response speed is as slow as several tens of milliseconds or more, its use as a display is limited. In recent years, a liquid crystal element called TFT has been developed for such a simple matrix type. Since this type creates a transistor in each pixel, the problems of crosstalk and response speed are solved, but it is industrially very difficult to create a liquid crystal element without a defective pixel as the area increases. Difficult and, if possible, at great cost.

In order to improve the drawbacks of the conventional liquid crystal device, the use of a bistable liquid crystal device is clarified by Clark and Lagerw.
all) proposed. (JP-A-56-107
216, U.S. Pat. No. 4,367,924) As the liquid crystal having the bistability, a ferroelectric liquid crystal having a chiral smectic C phase or a chiral smectic H phase is generally used. Since the ferroelectric liquid crystal performs inversion switching by spontaneous polarization, the ferroelectric liquid crystal has a very fast response speed and can exhibit a bistable state 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, Chandani and Takezoe have also proposed a chiral smectic antiferroelectric liquid crystal device having three stable states (Japanese Journal of Applied Physics).
of Applied Physics) 27, 198
8 years L729 page).

In such a chiral smectic liquid crystal element, as described in, for example, "Structure and Physical Properties of Ferroelectric Liquid Crystal" (Corona Publishing Co., Atsuo Fukuda, Hideo Takezoe, 1990), a zigzag alignment defect is formed. However, there is a problem that the contrast is significantly reduced. This defect is caused by the fact that the layered structure of the chiral smectic liquid crystal carried between the upper and lower substrates forms two types of chevron-like structures. Recently, there has been a movement to eliminate the chevron structure that causes the low contrast, and to reveal a layered structure called a bookshelf (hereinafter referred to as a bookshelf) or a structure close thereto to realize high contrast (for example, "Next-generation liquid crystal displays and liquid crystal materials" CMC Corporation, edited by Atsuo Fukuda, 1992). One method is to use a naphthalene-based liquid crystal material. In this case, the tilt angle is 10
22. It is about the degree and the ideal maximum transmittance is obtained.
There is a problem that the transmittance is very small as compared with 5 degrees and the transmittance is low, and there is also a problem that the bookshelf structure does not reversibly appear with respect to temperature. Another typical example is a method of inducing a bookshelf structure by applying a high electric field from the outside to a liquid crystal element having a chevron structure, but this method also has instability against external stimuli such as temperature. It's a problem. These bookshelf types have just been discovered, and there are various other problems for practical use.

Furthermore, a liquid crystal compound having a perfluoroether side chain as a liquid crystal having a structure of a bookshelf or a structure close to the bookshelf (US Pat. No. 5,262,082, International Patent Application WO 93/22396, 1993 4th Ferroelectric Liquid Crystal International Conference) P-46, Marc D. Radcliffe
Are disclosed. This liquid crystal can exhibit a bookshelf or a structure having a small layer inclination angle close to it without using an external field such as an electric field, and is suitable for a high-speed, high-definition, large-area liquid crystal element and a display device. However, further improvements are required in terms of speed, orientation, contrast, driving stability, etc. of liquid crystal elements. Moreover, in addition to improving each characteristic, a method and invention for improving a plurality of characteristics are required for higher performance.

[0007]

The present invention has been made in view of such a conventional technique. In fact, in the conventional liquid crystal composition and liquid crystal element, there were cases where there was a difference in stability between the two stable states (here, U1 and U2) of the ferroelectric liquid crystal element. That is, there may be a problem of "initial asymmetry" in which pulse widths required for switching from U1 to U2 and switching from U2 to U1 are different. This is not only because the display characteristics of the display are inferior from the initial stage, but also the durability characteristics are inferior, and there are many cases in which major problems relating to reliability occur.

Therefore, the present invention is intended to realize a highly reliable chiral smectic liquid crystal device, and also to provide a display device of high brightness and high contrast using the device.

More specifically, the present invention is intended to realize a liquid crystal element and a display device which have high reliability and which are free from the problem of initial asymmetry especially by using a specific liquid crystal composition.

[0010]

The present invention provides a chiral smectic liquid crystal composition comprising at least one or more optionally branched carbon chain having 2 to 30 carbon atoms and having at least one perfluorocarbon. In the non-liquid crystal perfluoro compound, one or more methylene groups in the carbon chain are -Y-, -YCO-, -C.
OY-, -CO-, -OCOO-, -CH = CH-,-
It may be replaced by C≡C- (Y is O or S), and -OH or -NRR 'in any of the carbon chains.
(R and R ′ are the same or different hydrogen, or an alkyl group having 1 to 5 carbon atoms) or —COOH may be substituted, and α (α is a single or plural —OH. , -NH ₂ , and phenyl group which may be substituted with -F) and a compound which may be substituted, and at least one liquid crystal compound are contained in the liquid crystal composition.

Further, the present invention has at least electrodes on the upper and lower substrates, and an alignment control layer having different alignment actions for liquid crystals on the upper and lower substrates, wherein at least one of the alignment control layers is made of polyimide. In a liquid crystal device having a liquid crystal sandwiched therebetween, the liquid crystal has a fluorocarbon end portion and a hydrocarbon end portion, and the both end portions are bound by a central nucleus, thereby forming a smectic phase or potentially a smectic phase. The fluorine-containing liquid crystal compound group has 70% by weight or more, and the fluorine-containing liquid crystal compound contains 30% by weight or more of the liquid crystal compound containing at least one ether oxygen in the chain in the fluorocarbon terminal chain. A liquid crystal device containing at least one kind of non-liquid crystalline perfluoro compound. The present inventors have realized a chiral smectic liquid crystal device of high speed, high contrast, large area, high definition, and high brightness, in which the above liquid crystal composition and liquid crystal device exhibit a structure with a small layer tilt angle such as a bookshelf. It was made possible and found to be reliable, especially without the initial asymmetry problem.

In the present invention, the non-liquid crystalline perfluoro compound means a compound having the following structure.

A perfluoro compound comprising an optionally branched carbon chain having 2 to 30 carbon atoms and having at least one perfluoro carbon, wherein one or more methylene groups in the carbon chain are Y-, -YCO-, -C
OY-, -CO-, -OCOO-, -CH = CH-,-
It may be replaced by C≡C- (Y is O or S), and -OH or -NRR 'in any of the carbon chains.
(R and R ′ are the same or different hydrogen, or an alkyl group having 1 to 5 carbon atoms) or —COOH may be substituted, and α (α is a single or plural —OH. , -NH ₂ , and a phenyl group which may be substituted with -F) may be substituted.

In the present invention, the ether oxygen in the chain means the oxygen forming the main chain in the perfluoroether chain.

[0015]

FIG. 1 shows an example of a chiral smectic liquid crystal device of the present invention. Reference numeral 1 is a liquid crystal layer composed of a chiral smectic liquid crystal composition. Usually, the layer thickness is preferably 5 μm or less in order to exhibit bistability. Two
Is a substrate, and glass, plastic, or the like is used.
3 is a transparent electrode such as ITO. Reference numeral 4 denotes an orientation control layer, which requires a uniaxial orientation control layer on at least one substrate. Polyimide is used for at least one of the orientation control layers. As a forming method, usually, a solution is coated on a substrate to form a film of polyamic acid which is a polyimide precursor, and then heat treatment is performed to form a polyimide film.
By rubbing the surface with a fibrous material such as velvet, cloth or paper, a polyimide orientation control layer is obtained.

The liquid crystal element of the present invention is a liquid crystal element using polyimide for at least one orientation control layer,
The structure is not limited as long as the liquid crystals are subjected to different alignment treatments on the upper and lower sides and contain the specific compound as a liquid crystal and have a predetermined function.

As a concrete structure of the polyimide as the orientation control layer which is important for the device constitution in the present invention, a polyimide comprising a repeating unit represented by the following general formula A is preferable.

[0018] [Formula ^{A] (-K-P 1 -L} 1 -M 1 - (L 2) a -P 2 -)

[0019]

Embedded image Or an alkylene group having 1 to 20 carbon atoms, P ¹ ,
P ² represents an imide bond. M ¹ represents a single bond or —O—, and a represents 0, 1, 2. )

Specific structures of these polyimides include, for example, the following repeating unit structures.

[0021]

Embedded image

In addition to the above-mentioned orientation control layer, an insulating layer as another short-circuit preventing layer for the upper and lower substrates, or another organic material layer or inorganic material layer may be formed. Reference numeral 5 is a sealing material that bonds the substrates together. In addition, a gap control spacer (not shown) such as silica beads is provided between the substrates.
6 is a lead wire, 7 is a signal power source, 8 is a polarizing plate, and 9 is a light source. Switching is performed in response to a switching signal from 7 and functions as a light valve for a display element or the like.
Further, if the three transparent electrodes are arranged in a matrix in the upper and lower cross, pattern display and pattern exposure become possible, and they are used as, for example, displays for personal computers, word processors, etc., and light valves for printers.

In the present invention, a fluorocarbon terminal portion and a hydrocarbon terminal portion used as a liquid crystal component in the present invention are contained, and at least one ether oxygen in the chain is contained in the fluorocarbon terminal chain, and both terminal portions are bound by a central nucleus. The fluorine-containing liquid crystal compound having a smectic mesophase or a latent smectic mesophase is disclosed in US Pat. No. 5,262,082 and International Patent Application WO
93/22396, 1993 4th International Conference on Ferroelectric Liquid Crystals P-46 (Marc D. Radcliffe et al.), Which is a perfluoroether liquid crystal compound.

As used herein, a compound having a latent smectic mesophase does not show a smectic mesophase by itself, but in a mixture with a compound having a smectic mesophase or a compound having another latent smectic mesophase, A compound that develops a smectic mesophase under appropriate conditions.

The above perfluoroether liquid crystal compound can be represented by the following general formula I-1 and is preferably used from the viewpoint of having good liquid crystallinity.

[General Formula I-1]

[0027]

Embedded image And a, b and c are each independently 0 or 1 to 3
Represents the integer. However, a + b + c is at least 2.

A and B may be oriented in either direction,
Independently, -COO-, -COS-, -COSe-,
_{-COTe -, - (CH 2 CH} 2) k - (k represents an integer of from 1 4), - C≡C -, - CH = CH -, - CH =
_{N -, - CH 2 -O -} , - CO -, - O-, a single bond.

X, Y and Z are independently -H and -C.
l, -F, -Br, -I, -OH, -OCH 3, -C
H _3, represents -CF _3, -OCF _3, -CN, and -NO _2.
l, m, and n each independently represent an integer of 0 to 4.

[0030] D is _{-COO-C r H 2r -,} - O-C r H 2r
_{-, - O (C s H} 2s O) t -C r 'H 2r' -, - C r H 2r -,
-OSOO -, - SOO -, - SOOC r H 2r -, - C r
_{H 2r -N (C p H 2p} + 1) -SOO -, - C r H 2r -N (C
_{p H 2p + 1) -CO- (} r, r ' 1 each independently represent an integer of up to 20, p is from 0 to 4 representing an integer .s are each (C _s H _2s O) to 1 to 10 independently
Represents an integer, and t represents an integer from 1 to 6. ) Represents.

[0031] R is _{-O- (C q H 2q -O)} w -C q 'H
_{2q '+ 1, - (C} q H 2q -O) w -C q' H 2q '+ 1, -C q H 2q
_{-R ', - O-C q} H 2q -R', - COO-C q H 2q -
_{R ', - OCO-C q} H 2q -R' (R ' is -Cl, -
_{F, -CF 3, -NO 2,} -CN, -H, -COO-C q '
_{H 2q '+ 1, -OCO-} C q'' represents _{+ 1, q, q' H} 2q each independently represents an integer of 1 to 20. w is 1 to 10
Represents the integer. ), R may be linear or branched.

[0032] Rf is _{- (C x F 2x O)} z C y F 2y is _{+ 1,} x 1 is independently in each of the (C _x F _2x O) 10
Is an integer from 1 to 10, y is an integer from 1 to 10,
z is an integer from 1 to 10. )

Further, specific structural examples of the perfluoroether liquid crystal compound include compounds having the following structures.

[0034]

[Chemical 6]

[0035]

[Chemical 7]

[0036]

Embedded image

Specific examples of the non-liquid crystal perfluoro compound contained in the liquid crystal composition of the present invention include compounds having the structures shown below. (Note that the present invention is not limited to the exemplified compounds below.)

[0038]

Embedded image

[0039]

Embedded image

[0040]

Embedded image

As the liquid crystal, at least one of fluorine-containing liquid crystal compounds having a fluorocarbon terminal portion and a hydrocarbon terminal portion, the both terminal portions being bound by a central nucleus, and having a smectic mesophase or a latent smectic mesophase. At least one compound having at least one ether oxygen in the chain (perfluoroether liquid crystal compound) and at least one non-liquid crystal perfluoro compound are essentially contained. By containing these two kinds of compounds, good driving characteristics can be obtained characteristically in a wide temperature range.

To obtain these effects, at least one kind of non-liquid crystalline perfluoro compound is 0.01% by weight.
It is preferable that it is contained above. Further, in order to obtain sufficient contrast and response speed, a bookshelf or a structure having a small layer inclination angle close thereto is preferable, and for this reason, 50% by weight or more of a perfluoroether liquid crystal compound is contained in the liquid crystal composition of the present invention. It is preferably contained. Further, a perfluoroalkyl liquid crystal compound can be contained from the viewpoint of good compatibility with the perfluoroether liquid crystal compound. Furthermore, a so-called hydrocarbon type liquid crystalline compound having no perfluorocarbon chain can be contained as another component. The liquid crystal composition used in the present invention contains a chiral compound.

In the present invention, the liquid crystal composition contains
Other compounds such as dyes, pigments, antioxidants, UV absorbers and other additives may also be included.

The liquid crystal device of the present invention constitutes a liquid crystal device having various functions. The data format and SY which are image information having scanning line address information shown in FIGS. 2 and 3.
A liquid crystal display device is realized by using communication synchronization means using N signals. The reference numerals in the figure are as follows.

101 chiral smectic liquid crystal display device 102 graphic controller 103 display panel 104 scanning line driving device 105 information line driving device 106 decoder 107 scanning signal generating device 108 shift register 109 line memory 110 information signal generating device 111 driving control circuit 112 GCPU 113 Host CPU 114 VRAM

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. The graphic controller 102 is a CPU
(Central processing unit, abbreviated as GCPU) and VRAM
(Image information storage memory) Host CPU 1 with 114 as a core
13 manages image information and communicates with the liquid crystal display device 101. Note that a light source is disposed on the back surface of the display panel.

In the liquid crystal device of the present invention, since the liquid crystal element which is the display medium has the good switching characteristics as described above, it exhibits excellent driving characteristics and reliability, high definition, high speed,
A large area display image can be obtained.

As a method of driving the liquid crystal element of the present invention, for example, Japanese Patent Laid-Open Nos. 59-193426 and 59-19 are available.
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. 6 is an example of a waveform diagram of the 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. FIG.
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. 6A, S _S is a selected scan waveform applied to the selected scan line, S _N is an unselected 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 takes a white display state.

FIG. 6B shows the drive waveforms shown in FIG. 6A, which are time-series waveforms when the display shown in FIG. 4 is performed.

In the driving example shown in FIG. 6, 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. 6 are determined by the switching characteristics of the liquid crystal material used.

FIG. 7 shows changes in the transmittance T when the drive voltage (V _S + V _I ) is changed while keeping the bias ratio, which will be described later, constant, that is, VT characteristics. Where Δ
t = 50 μsec, bias ratio V _I / (V _I + V _S ) = 1
It is fixed at / 3. The positive side of FIG. 7 is shown in FIG. 6 (I
_N -S _S), the negative side waveform shown by (I _S -S _S) is applied.

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 this time, ΔV = (V ₃ −V ₁ ) / (V ₃ + V ₁ ) is called a voltage margin, which is a parameter of the voltage width capable of matrix driving. 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 in waveform _{(A) (I N -S S} ). Of course, it is possible to increase the value of V ₃ by increasing the bias ratio, increasing the bias ratio corresponds to a large amplitude of a data signal, an increase in flickering in image quality, contrast Is undesirably caused.

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, 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 voltage is kept constant,
It is also possible to drive by changing the voltage application time Δt. The above voltage may be used as the voltage application time as it is, and at this time, the voltage application time threshold is Δt.
₁ , the voltage application time crosstalk value is Δt _2, and (Δ
t ₂ −Δt ₁ ) / (Δt ₂ + Δt ₁ ) = ΔT is called a voltage application time margin.

At such a certain constant temperature, two states of "black" and "white" can be written in 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.

[0059]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

The compounds used are described below.

[0061]

[Chemical 12]

[0062]

Embedded image

Liquid crystal cells were prepared in the following two types L and M.

The liquid crystal cell L has a glass substrate with ITO and NMP / nBC = 2 of polyimide precursor LP64 manufactured by Toray Industries, Inc.
/ 1 solution was spin-coated and baked to form a polyimide, and then two pieces subjected to rubbing treatment were sprinkled with silica bead spacers on the substrate, and the gap was adjusted and bonded to obtain a liquid crystal cell having a thickness of 2.0 μm. . The thickness of this polyimide film was 300Å.

In the liquid crystal cell M, a substrate having the above-described polyimide film as an alignment film and a substrate obtained by spin-coating a glass substrate with ITO with a silane coupling agent (octadecyltriethoxysilane) and heat-treating the substrate are bonded together. 0.0μ
A liquid crystal cell having a thickness of m was used.

As the liquid crystal composition, the above-mentioned compound A:
B: C: D: E: F: G, 50: 15: 10: 15:
Composition X, 50: 1, mixed in a ratio of 3: 5: 2.
Composition Y was a mixture of 5: 10: 15: 3: 5: 0.

The bookshelf property (BS property) of the layer structure of each liquid crystal composition immediately after injection at 25 ° C. was generally good. Regarding the orientation, the cell M was superior to the cell L in orientation.

These liquid crystal elements were driven by using the driving waveform shown in FIG. The bias ratio is 1/3 and (V
_I + V _S) is fixed to 20V, Delta] t ¹ the shortest Delta] t to be switched by applying a voltage (I _N -S _S) a voltage application time as a variable to U1 → U2, by inverting the polarity of the electrodes at the same waveform The shortest Δt for switching from U2 to U1 by Δt
² and the time the (Δt ¹ -Δt ²⁾ was the initial asymmetry parameter [Delta] T. If this value is positive, U1; if negative, U2
It can be said that the direction is more stable. Further, the voltage application time margin (initial margin) immediately after the injection was measured.

[Example 1, Comparative Examples 1 to 3] Liquid crystal compositions X and Y were injected into liquid crystal cells L and M, respectively, and an initial asymmetry parameter ΔT and an initial margin were measured. The results are shown in the table.

[0070]

[Table 1]

As described above, in Example 1 satisfying the requirements of the present invention, the initial asymmetry is very small and the initial margin is larger than those of the other comparative examples. In such a liquid crystal element having a large initial margin, a large margin remains even after being driven or left for a long time, and the reliability of the liquid crystal element and further the display device is improved.

[Examples 2-4, Comparative Examples 4-7] Further,

[0073]

Embedded image A: B: C: D: E: F: H = 52: 10: 15: 1
5: 3: 5: 1 with composition P, A: B: C: D: E: F: H = 52: 10: 15: 1
Composition Q, 5: 3: 5: 0, A: B: C: D: E: F: I = 52: 10: 15: 1
5: 3: 5: 0.5 with composition R, A: B: C: D: E: F: J = 52: 10: 15: 1
The composition S is 5: 3: 5: 2.

These were injected into the cell prepared previously, and the asymmetry parameter and the initial margin were measured.

The results are shown in the table below.

[0076]

[Table 2]

[0077]

As described above, according to the liquid crystal device of the present invention, a chiral smectic liquid crystal device of high brightness can be realized by exhibiting a structure of a bookshelf or a layer having a small layer tilt angle, and further higher. It has a great effect on reliability, especially on monostable storage.

[Brief description of drawings]

FIG. 1 is a diagram showing a cross-sectional view 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 schematic diagram of a display pattern when actual driving is performed with the time-series driving waveform shown in FIG.

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

FIG. 6 is a diagram showing an example of drive waveforms used to drive the liquid crystal element of the present invention.

FIG. 7 is a graph (VT characteristic diagram) showing a change in transmittance when a drive voltage is changed according to the present invention. 1 Liquid crystal layer 2 Substrate 3 Transparent electrode 4 Alignment control layer 5 Sealing material 6 Lead wire 7 Signal power source 8 Polarizing plate 9 Light source 101 Chiral smectic liquid crystal display device 102 Graphic controller 103 Display panel 104 Scan line driving device 105 Information line driving device 106 Decoder 107 Scan Signal Generator 108 Shift Register 109 Line Memory 110 Information Signal Generator 111 Drive Control Circuit 112 GCPU 113 Host CPU 114 VRAM

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Sato 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Shinichi Nakamura 3-30-2 Shimomaruko, Ota-ku, Tokyo Kya Non non corporation

Claims (8)

[Claims] 1. A chiral smectic liquid crystal composition, which is a non-liquid crystalline perfluoro compound having at least one or more perfluorocarbons and at least one perfluorocarbon and having an optionally branched carbon chain having 2 to 30 carbon atoms. And one or more methylene groups in the carbon chain are -Y-, -YCO-, -COY-, -CO-, -OCO.
It may be replaced with O-, -CH = CH-, -C≡C- (Y is O or S), and -OH or -NRR '(R and R'are any of the carbon chains. The same or different hydrogen, or an alkyl group having 1 to 5 carbon atoms.)
Or -COOH may be substituted, also the terminal portion alpha (alpha is one or more -OH, -NH _2, -
A liquid crystal composition comprising a compound in which F may be substituted and a phenyl group in which F may be substituted and at least one liquid crystal compound. 2. An upper and lower substrate having at least electrodes, and an upper and lower substrate having an alignment control layer having different alignment actions with respect to liquid crystals, wherein at least one of the alignment control layers is made of polyimide, and the liquid crystal is provided between the upper and lower substrates. In the liquid crystal element sandwiching, the liquid crystal has a fluorocarbon terminal portion and a hydrocarbon terminal portion, the both terminal portions are bound by a central nucleus, and a fluorine-containing compound having a smectic phase or potentially a smectic phase. The liquid crystal compound group occupies 70% by weight or more, and at least one of the fluorine-containing liquid crystal compounds contains 30% by weight or more of the liquid crystal containing at least one ether oxygen atom in the chain of the fluorocarbon chain. Is the above-mentioned branched carbon chain having 2 to 30 carbon atoms having at least one perfluorocarbon In the non-liquid crystal perfluoro compound, one or more methylene groups in the carbon chain are -Y-, -YCO-, -COY-, -CO-, -O.
COO-, -CH = CH-, -C [identical to] C- (Y is O or S.), -OH, -NRR '(R and R'are any of the carbon chains. The same or different hydrogen, or an alkyl group having 1 to 5 carbon atoms) or -COOH may be substituted, and α (α is a single or plural -OH, -N) at the terminal portion.
A liquid crystal element, which is a chiral smectic liquid crystal composition containing a compound in which H ₂ and —F may be substituted and a phenyl group may be substituted). 3. The liquid crystal device according to claim 2, wherein the amount of the non-liquid crystal perfluoro compound added is 0.01 to 5% by weight based on the whole liquid crystal composition. 4. The liquid crystal device according to claim 2, wherein the polyimide comprises a repeating unit represented by the following general formula A. [Formula ^{A] (-K-P 1 -L} 1 -M 1 - (L 2) a -P 2 -) ## STR1 ## Or an alkylene group having 1 to 20 carbon atoms, P ¹ ,
P ² represents an imide bond. M ¹ represents a single bond or —O—, and a represents 0, 1, 2. ) 5. A compound containing at least one linkage of ether oxygen in the fluorocarbon terminal chain of said fluorine-containing liquid crystal _{compound, -D (C x F 2x O} ) z C y F
_{2y + 1} (x is 1 to 1 independently for each (C _x F _2x O)
An integer of 0, y is an integer of 1 to 10, and z is 1 to 10
Of an integer, D is a single _{bond, -COO-C r H 2r -} , -
_{O-C r H 2r -,} - O- (C s H 2s O) t -C r 'H 2r' -,
_{-OSO 2 -, - SO 2 -} , - SO 2 -C r H 2r -, - C r
_{H 2r -, - C r H} 2r -N (C p H 2p + 1) -SO 2 -, - C r
_{H 2r -N (C p H 2p} + 1) -CO-, an integer r and r '1 are each independently 20, s of each C _s H
_2s O is independently an integer of 1 to 10, t is an integer of 1 to 6, and p is an integer of 0 to 4). The liquid crystal element according to any one of 2 to 4. 6. The fluorine-containing liquid crystal compound, wherein the compound containing at least one ether oxygen in the chain in the fluorocarbon terminal chain is a compound represented by the following general formula I-1. The liquid crystal element described. [General Formula I-1] And a, b, and c each independently represent 0 or an integer of 1 to 3. However, a + b + c is at least 2. A, B
Can be in either direction, and independently, -CO
O-, -COS-, -COSe-, -COTe-,-
_{(CH 2 CH 2) k -} (k represents an integer of 1 to 4), -
C≡C -, - CH = CH - , - CH = N -, - CH 2 -
Represents O-, -CO-, -O-, and a single bond. X, Y and Z are independently -H, -Cl, -F, -Br, -I,-.
_{OH, -OCH 3, -CH 3,} -CF 3, -OCF 3, -C
N, representing the -NO _2. l, m, and n are 0 independently.
Represents an integer of 4. D is _{-COO-C r H 2r -,} - O-C r
_{H 2r -, - O (C} s H 2s O) t -C r 'H 2r' -, - C r H 2r
-, - OSOO -, - SOO -, - SOOC r H 2r -,
_{-C r H 2r -N (C p} H 2p + 1) -SOO -, - C r H 2r -
_{N (C p H 2p + 1} ) -CO- (r, r ' represents an integer of from independently 1 to 20, p is an integer from 0 to 4 .s are each (C _s H _2s O) independently represents an integer of 1 to 10, and t represents an integer of 1 to 6.)
Represents R is _{-O- (C q H 2q -O)} w -C q 'H 2q' + 1,
_{- (C q H 2q -O)} w -C q 'H 2q' + 1, -C q H 2q -R ',
_{-O-C q H 2q -R '} , - COO-C q H 2q -R', - O
_{CO-C q H 2q -R '} (R' is -Cl, -F, -CF _{3,
-NO 2, -CN, -H, -COO} -C q 'H 2q' + 1, -O
CO-C _q represents a _{'H 2q' + 1, q} , q ' each independently represents an integer of from 1 to 20. w represents an integer of 1 to 10. ), R may be linear or branched. Rf is-
_{(C x F 2x O) z} C y F 2y is _{+ 1,} x is each (C _x
F _2x O) is an integer from 1 to 10 independently, and y is 1
Is an integer from 1 to 10, and z is an integer from 1 to 10. ) 7. The liquid crystal device according to claim 6, wherein the compound represented by the general formula I-1 is a compound having a phenylpyrimidine core. 8. A liquid crystal device using the liquid crystal element according to claim 2.