JP3160700B2 - Liquid crystal element and liquid crystal device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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. It is widely used as a video output for televisions and VTRs, or as a monitor for personal computers. However, due to the characteristics of the CRT, flicker and scanning fringes due to insufficient resolution lower the visibility of a still image, and the phosphor deteriorates due to burn-in. Recently, CRT
It can be seen that the electromagnetic waves generated by the harmful effects on the human body, which may harm the health of the VDT worker. And
Because of its structure, it has a large volume behind the screen,
It may hinder home space savings and may not be able to fulfill its responsibility as a display in the 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)
Ifrich), "Applied Physics Letters" (Applied Physics Letter)
s ") Volume 18, Issue 4 (issued February 15, 1971)
Twisted pages shown on pages 127-128
A device using a twisted nematic liquid crystal is known. One is a simple matrix type liquid crystal element which has an advantage in cost. 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. In addition, since the response speed is as slow as several tens of milliseconds or more, the use as a display has been limited. In recent years, a liquid crystal element called a TFT has been developed for such a simple matrix type. Since this type creates a transistor for each pixel, it solves the problems of crosstalk and response speed, but the larger the area, the more industrially it is extremely difficult to create a liquid crystal element without defective pixels. Difficult and costly, if possible.

As an improvement over the disadvantages of the conventional liquid crystal device, the use of a bistable liquid crystal device has been proposed by Clark and Lagerwell.
all). (JP-A-56-107
216, U.S. Pat. No. 4,367,924) As the liquid crystal having this 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 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).
of Applied Physics) 27, 198
8 years, L729).

In such a chiral smectic liquid crystal element, for example, as described in “Structure and Physical Properties of Ferroelectric Liquid Crystal” (Corona Co., Atsuo Fukuda, Hideo Takezoe, 1990), a zigzag alignment defect is formed. This causes a problem that the contrast is remarkably reduced due to the occurrence of. This defect is due to 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 low contrast and to exhibit a layered structure called a bookshelf (hereinafter, this structure is referred to as a bookshelf) or a structure similar thereto, thereby realizing high contrast (for example, "Next-generation liquid crystal display and liquid crystal material", edited by CMC Corporation, Atsuo Fukuda, 1992). One method is to use a naphthalene-based liquid crystal material. In this case, a tilt angle of 10 is used.
Degree, and an ideal maximum transmittance can be obtained.
There is a problem that it is very small as compared with 5 degrees and has a low transmittance, and there is also a problem that the bookshelf structure does not appear reversibly with respect to temperature. As another typical example, there 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 to external stimuli such as temperature. It is a problem. These bookshelf types are still being discovered, and there are various other problems for practical use.

Further, a liquid crystal compound having a perfluoroether side chain as a book shelf or a liquid crystal having a structure similar thereto (US Pat. No. 5,262,082, International Patent Application WO 93/22396, 4th International Conference on Ferroelectric Liquid Crystals, 1993) P-46, Marc D. Radcliffe
Are disclosed. This liquid crystal can exhibit a bookshelf or a structure having a small layer tilt angle close to the bookshelf 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 the speed, alignment, contrast, drive stability and the like of the liquid crystal element. In addition, there is a need for a method of improving a plurality of characteristics and an invention for higher performance as well as improvement of each characteristic.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of such prior art. The present invention intends to realize a chiral smectic liquid crystal element having a high-speed, high-contrast, large-area, high-definition, high-brightness, high-reliability liquid crystal structure having a bookshelf or a liquid crystal structure with a small layer tilt angle close thereto, and It is an object of the present invention to provide a liquid crystal device with high luminance and high contrast using the element.

[0008]

Means for Solving the Problems As a result of intensive studies, the present inventors have at least electrodes for applying voltage and an orientation control layer on the upper and lower substrates, and at least one of the orientation control layers has polyimide. In the liquid crystal element using, different orientation treatments are applied vertically, and the liquid crystal includes a fluorocarbon terminal portion and a hydrocarbon terminal portion, and includes at least one ether oxygen in the chain in the fluorocarbon terminal chain, 10% by weight or more of a fluorine-containing liquid crystal compound having both end portions bound by a central nucleus and having a smectic mesophase or potentially a smectic mesophase having at least one or more ether oxygen atoms in one chain. At least one or more 2
One of the compounds in having an ether oxygen linkage 10 wt% or more <br/> and a characterized by the use of chiral smectic liquid crystal composition at least one or more of the three compounds in having an ether oxygen linkage containing at least 10 wt% Liquid crystal element realizes a very high-speed response, and exhibits a structure with a small layer tilt angle close to the bookshelf or close to it.
It has been found that it is possible to realize a chiral smectic liquid crystal device with high contrast, large area, high definition, and high brightness, and shows that it has good driving characteristics, high reliability, and driving stability especially in a wide temperature range. In the present invention, the term "ether oxygen in the chain" refers to oxygen that forms the main chain in the perfluoroether chain.

[0009]

FIG. 1 shows an example of a chiral smectic liquid crystal device of the present invention. Reference numeral 1 denotes 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. 2
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. In addition, polyimide is used for at least one orientation control layer. As a forming method, a polyamic acid as a polyimide precursor is usually formed on a substrate by solution coating, followed by heat treatment 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.

In the present invention, an element having an asymmetric alignment film configuration is used. When the chiral smectic liquid crystal composition is used in a device having an asymmetric alignment film configuration having a polyimide alignment control film, the device has good driving characteristics in a very wide temperature range, and has high reliability and good driving stability. It is possible. As the alignment film, as a specific structure of the polyimide used from the viewpoint of characteristics, a polyimide including a repeating unit represented by the following general formula I is preferable.

[General formula I] (-K-P ¹ -L ¹ -M ^1- (L ² ) _a -P ^2- )

[0012]

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

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

[0014]

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In addition to the orientation control layer, an insulating layer or another organic or inorganic layer may be formed as a short-circuit preventing layer for the upper and lower substrates. Reference numeral 5 denotes a gap control spacer, for example, silica beads or the like is used. 6 is a lead wire, 7 is a signal power supply, 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 such as a display element. Also,
If the three transparent electrodes are arranged in a matrix with upper and lower crosses, pattern display and pattern exposure become possible, and they are used, for example, as displays for personal computers and word processors, and as light valves for printers.

The perfluoroether liquid crystalline compound used in the chiral smectic liquid crystal composition of the present invention is described 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.), Comprising a fluorocarbon terminal portion and a hydrocarbon terminal portion, and having at least one terminal in the fluorocarbon terminal chain. A fluorine-containing liquid crystal compound containing ether oxygen in two chains, both terminal portions of which are linked by a central nucleus, and having a smectic mesophase or a potential smectic mesophase.

The compound having a latent smectic mesophase herein refers to a compound having a smectic mesophase or a compound having another potential smectic mesophase, even if the compound does not exhibit the smectic mesophase itself. Refers to compounds that, under appropriate conditions, express a smectic mesophase. It can be represented by the following general formula II.

[General formula II]

[0019]

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

M and N are each independently -COO-,-
COS -, - COSe -, - COTe -, - (CH 2 C
H ₂ ) _d- (d represents an integer of 1 to 4), -C≡C-,
-CH = CH -, - CH = N -, - CH 2 -O -, - C
O-, -O-, or a single bond, and the orientation may be any.

X, Y and Z are each independently -H, -Cl
-, - F, -Br, -I , -OH, -OCH 3, -C
H ₃ , —CF ₃ , —OCF ₃ , —CN, and —NO ₂ .
l, m, and n each independently represent an integer of 0 to 4.

[0022] G is _{-COO-C e H 2e -,} - O-C e H 2e
_{-, - O (C e "} H 2e" O) t -C e 'H 2e' -, - C e H
_{2e -, - OSOO -, -} SOO -, - SOOC e H
_{2e -, - C e H 2e} -N (C p H 2p + 1) -SOO -, - C e
_{H 2e -N (C p H 2p} + 1) -CO- (e, e ' represents an integer of from 1 independently to 20, p is an integer from 0 to 4 .e "is respectively ( Ce _{" H2e"} O) independently represents an integer of 1 to 10, and t represents an integer of 1 to 6.)

[0023] A is _{-O- (C f H 2f -O)} u -C f 'H
_{2f '+ 1, - (C} f H 2f -O) u -C f' H 2f '+ 1, -C f H 2f -
_{R ', - O-C f} H 2f -R', - COO-C f H 2f -
_{R ', - OCO-C f} H 2f -R' (R ' is -Cl, -
_{F, -CF 3, -NO 2,} -CN, -H, -COO-C f '
_{H 2f '+ 1, -OCO-} C f'' represents a _{+ 1, f, f' H} 2f each independently represents an integer of 1 to 20. u is 1 to 10
Is an integer. A represents a linear or branched chain.

[0024] R is - (C _x F _2x O) a _z C _y F _{2y + 1,}
x is 1 to 10 independently for each C _x F _2x O group
And y is an integer from 1 to 10,
z is an integer from 1 to 10. )

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

[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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[0031]

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In the present invention, the liquid crystal includes a fluorocarbon terminal portion and a hydrocarbon terminal portion, and the fluorocarbon terminal chain includes at least one ether oxygen in the chain, and the both terminal portions are bound by a central nucleus. , Among fluorine-containing liquid crystal compounds having a smectic intermediate phase or a potential smectic intermediate phase, at least one compound having at least one ether ether in a chain, and at least one compound having two ether oxygens in a chain, and at least one compound The compound having an ether oxygen in the three chains is essentially contained. By containing these three compounds , good driving characteristics, high reliability and driving stability can be obtained characteristically over a wide temperature range. To obtain these effects, at least one kind of a compound in having an ether oxygen linkage to 10 wt% or more of at least one or more compounds having two chain ether oxygen and 10% by weight or more of at least one or more compounds having three chain ether oxygen 1
A liquid crystal composition containing 0% by weight or more is used . In addition, in order to obtain sufficient contrast and response speed, it is preferable that the bookshelf or a structure having a small layer tilt angle close thereto is used,
For this reason, 50% by weight is contained in the liquid crystal composition used in the present invention.
It is preferable that the above-mentioned perfluoroether liquid crystal compound is contained. Further, a perfluoroalkyl liquid crystal compound can be contained from the viewpoint of good compatibility with the perfluoroether liquid crystal compound.
Further, as another component, a so-called hydrocarbon type liquid crystal compound having no perfluorocarbon chain can be contained. And to the present invention
The chiral smectic liquid crystal composition used contains a chiral compound.

Specific examples of the perfluoroalkyl liquid crystalline compound described above include those described in JP-A-2-142755 and those having the following structures.

[0034]

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[0035]

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[0036]

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[0037]

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[0038]

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[0039]

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[0040]

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[0041]

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[0042]

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[0043]

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[0044]

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Further, as a specific example of a so-called hydrocarbon type liquid crystal compound having no perfluorocarbon chain as another component, the following structure is exemplified.

[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]

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[0052]

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[0053]

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[0054]

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[0055]

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[0056]

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[0057]

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[0058]

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[0059]

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[0060]

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[0061]

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[0062]

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

[0064]

[Table 1]

[0065]

[Table 2]

[0066]

[Table 3]

[0067]

[Table 4]

[0068]

[Table 5]

[0069]

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[0070]

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[0071]

[Table 6]

[0072]

[Table 7]

[0073]

[Table 8]

[0074]

[Table 9]

[0075]

[Table 10]

[0076]

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[0077]

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[0078]

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[0079]

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[0080]

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[0081]

Embedded image D-1: n = 6,2R, 5R D-2: n = 6,2S, 5R D-3: n = 4,2R, 5R D-4: n = 4,2S, 5R D-5: n = 3,2R, 5R D-6: n = 2,2S, 5R D-7: n = 2,2R, 5R D-8: n = 1,2S, 5R D-9: n = 1,2R, 5R

[0082]

Embedded image D-10: n = 1 D-11: n = 2 D-12: n = 3 D-13: n = 4 D-14: n = 6 D-15: n = 10

[0083]

Embedded image D-16: n = 8 D-17: n = 10

[0084]

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[0085]

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[0086]

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[0087]

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[0088]

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[0089]

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In the chiral smectic liquid crystal composition of the present invention, other compounds such as a dye, a pigment,
Additives such as antioxidants and ultraviolet absorbers can also be included.

The liquid crystal element of the present invention constitutes a liquid crystal device having various functions. The data format of the image information having the scanning line address information shown in FIGS.
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 Scan line driving device 105 Information line driving device 106 Decoder 107 Scan signal generating device 108 Shift register 109 Line memory 110 Information signal generating device 111 Drive control circuit 112 GCPU 113 Host CPU 114 VRAM

The generation of image information is performed 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 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.

The display device of the present invention exhibits excellent driving characteristics and reliability because the liquid crystal element as a display medium has good switching characteristics as described above, and exhibits 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, JP-A-59-193426 and JP-A-59-19
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 above driving method. FIG. 5 is a plan view of an example of a chiral smectic liquid crystal panel on 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 cross each other, and a chiral smectic liquid crystal is arranged between the scanning line and the data line at the intersection. Have been.

[0097] The S _S is selected scan waveform applied to the selected scanning line in FIG. 6 (A), the non-selection scanning waveform S _N is not selected, I _S is applied to the selected data line A selected information waveform (black) and _IN indicates a non-selected information signal (white) applied to an unselected data line. In the drawing, (I _S -S _S ) and (I _N -S _S ) are voltage waveforms applied to the pixels on the selected scanning line, and the pixels to which the voltage (I _S -S _S ) is applied are black. Taking the display state, the voltage (I _N −
The pixel to which S _S ) is applied takes a white display state.

FIG. 6B is a driving waveform shown in FIG. 6A, and is a time-series waveform when the display shown in FIG. 4 is performed.

In the driving example shown in FIG. 6, the minimum application time Δt of the unipolar voltage applied to the pixels on the selected scanning line
There corresponds to the write phase t ₂ time period of a one-line clearing phase t ₁ is set to 2? T.

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 a change in the transmittance T when the drive voltage (V _S + V _I ) is changed while a bias ratio described later is kept constant, that is, a VT characteristic. Where Δ
t = 50 μsec, bias ratio V _I / (V _I + V _S ) = 1
/ 3. The positive side of FIG. 7 is shown in FIG.
_N- S _s ), and the waveform shown by (I _s -S _s ) is applied to the negative side.

Here, V ₁ and V ₃ are called an actual drive threshold voltage and a crosstalk voltage, respectively. Also, V ₂ <V ₁ <V ₃
In this case, ΔV = V ₃ −V ₁ is referred to as a voltage margin, which is a voltage width in which matrix driving is possible. V ₃ is a chiral smectic liquid crystal display device driving on, it may be said that generally present. Specifically, a voltage value causing switching by V _B in the waveform of FIG. _{6 (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.

In our study, the bias ratio was 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-mentioned voltage is kept constant,
It is also possible to drive by changing the voltage application time Δt. The above-described voltage may be used as the voltage application time as it is, and in this case, the voltage application time threshold is Δt
₁ , the voltage application time crosstalk value is Δt _2, and (Δ
t ₂ −Δt ₁ ) = ΔT is referred to as a voltage application time margin.

At such a certain temperature, two states of “black” and “white” can be written to the selected pixel depending on the two directions of the information signal. The voltage margin or the voltage application time margin capable of maintaining the “white” state varies depending on the liquid crystal material and the element configuration, and is unique. Also,
Since the driving margin shifts due to a change in the environmental temperature, in the case of an actual display device, it is necessary to set optimal driving conditions for the liquid crystal material, the element configuration, and the environmental temperature.

[0106]

EXAMPLES 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.

[Example 1]

[0108]

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[0109]

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The liquid crystal cell used was a glass substrate provided with ITO and a polyimide precursor LP64 manufactured by Toray (the structural formula of the fired polyimide is as follows).

[0111]

Embedded image NMP / nBC = 2/1 solution is spin-coated, baked to obtain polyimide, rubbed, and then spin-coated with a silane coupling agent (octadecyltriethoxysilane) on the substrate and the glass substrate with ITO. Then, a silica bead spacer is sprinkled on the heat-treated substrate, a gap is formed, and the substrate is laminated and has a thickness of 1.8 μm.

The measurement of the layer inclination angle δ is described in Jpn. J. Ap
pl. Phys. 27. L725 (1988).

The drive waveform used was the waveform shown in FIG. The bias ratio was 1/3, (V _I + V _S ) was fixed at 18 V, and the voltage application time was variable to measure the margin.

A chiral smectic liquid crystal composition having the following composition (parts by weight) was prepared.

Composition α //////// (a) / (b) = 0
/ 0/0/45/30/0/15/0/5/2 composition β //////// (a) = 3/3/4
/ 40/20/0/20/0/5 composition γ //////// (a) / (b) = 3
/ 3/4/40/10/10/10/10/5/2 composition ρ //////// (b) = 0/0/0
/ 45/20/0/20/0/5 composition σ //////// (c) = 0/0/0
/ 45/20/0/20/0/10

The voltage application time threshold Δt ₁ and the voltage application time margin ΔT (μsec) immediately after the injection of each composition at 25 ° C.
The same applies hereinafter), ΔT ₅₀ after 50 hours, and ΔT (15) at 15 ° C. are shown in the following table.

[0117]

[Table 11]

The layer inclination angle of the composition α at 25 ° C. was 3.6 degrees.

Example 2 A 1.8 μm cell was prepared in the same manner as in Example 1 using polyimide having the following repeating units. Further, similarly to the first embodiment, ΔT (25), ΔT (25)
T (25) ₅₀ was measured using the following composition,
It is shown in the table below.

[0120]

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[0121]

[Table 12]

Comparative Example 1 A composition having the following composition was prepared.

Composition II //////// (a) = 3/3/4
/ 70/0/0/10/0/5

This composition was prepared at 25 ° C. in the cell of Example 1.
When evaluated by the same method, Δt₁(Μsec) is 43μ
sec, ΔT (25) is 8, ΔT (25 )₅₀Is 2, ΔT
(15) was 0.

Comparative Example 2 A cell (x) was prepared in the same manner as in Example 1 except that the polyimide of Example 1 was changed to polyvinyl alcohol (Aldrich). Thus, the compositions α and β of Example 1 were obtained.
Were evaluated in the same manner, and ΔT (2
5) There was no ΔT (25) ₅₀ .

In addition, a cell (y) in which the polyimide used in Example 1 was arranged vertically was prepared. The evaluation results of the compositions α, β, and γ of Example 1 are shown in the table below.

[0127]

[Table 13]

[0128]

As described above, according to the liquid crystal device of the present invention, a very high-speed response is realized, and a structure with a small layer tilt angle close to a bookshelf or a similar one is realized. A chiral smectic liquid crystal device with high contrast, large area, high definition and high brightness has been realized. The liquid crystal element of the present invention exhibits good driving characteristics particularly in a wide temperature range, and has high reliability and driving stability in an element having an asymmetric alignment film configuration having polyimide as an alignment film.

[Brief description of the drawings]

FIG. 1 is a diagram showing a 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 on which matrix electrodes are arranged.

FIG. 6 is a diagram showing an example of a driving waveform used for driving 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. DESCRIPTION OF SYMBOLS 1 Liquid crystal layer 2 Substrate 3 Transparent electrode 4 Alignment control layer 5 Spacer 6 Lead wire 7 Signal power supply 8 Polarizer 9 Light source 101 Chiral smectic liquid crystal display device 102 Graphic controller 103 Display panel 104 Scan line drive device 105 Information line drive device 106 Decoder 107 Scanning signal generator 108 Shift register 109 Line memory 110 Information signal generator 111 Drive control circuit 112 GCPU 113 Host CPU 114 VRAM

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shuji Yamada 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References Special Table 7-506368 (JP, A) US Patent 5417883 ( (US, A) U.S. Pat. No. 5,262,082 (US, A) WO 95/17481 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09K 19/00-19/34 C09K 19/42 -19/46 CA (STN) REGISTRY (STN)

Claims (7)

(57) [Claims] 1. A liquid crystal element having an electrode for applying a voltage at least on upper and lower substrates and an alignment control layer, wherein at least one of the alignment control layers is made of polyimide, different upper and lower alignment treatments are performed. A liquid crystal comprising a fluorocarbon end portion and a hydrocarbon end portion, and at least one ether oxygen in the chain in the fluorocarbon end chain, wherein both end portions are linked by a central nucleus, and a smectic mesophase or latent Among the fluorine-containing liquid crystal compounds having a smectic intermediate phase, at least one compound having one or more ether oxygen atoms in the chain is 10% by weight or more and at least one kind of 2
One of the compounds in having an ether oxygen linkage 10 wt% or more <br/> and a characterized by the use of chiral smectic liquid crystal composition at least one or more of the three compounds in having an ether oxygen linkage containing at least 10 wt% Liquid crystal element. 2. The liquid crystal device according to claim 1, wherein the polyimide comprises a repeating unit represented by the following general formula I. [General formula I] (-K-P ¹ -L ¹ -M ^1- (L ² ) _a -P ^2- ) Or an alkylene group having 1 to 20 carbon atoms, wherein P ¹ ,
P ² represents an imide bond. M ¹ represents a single bond or —O—, and a represents 0, 1, or 2. ) Fluorocarbon terminal chain of claim 3 wherein said fluorine-containing liquid crystal compound is represented by _{-V (C x F 2x O)} z C y F 2y + 1, x 1 are independently each C _x F _2x O At 10,
y is from 1 to 10, z is 10 1, V 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-,} r and r 'are 20 each independently 1, s is 1 to 10 independently in each of the C _s H _2s O group, t is 1 to 6 The liquid crystal device according to claim 1, wherein a chiral smectic liquid crystal composition wherein p is 0 to 4 is used. 4. The liquid crystal device according to claim 1, wherein the fluorine-containing liquid crystal compound uses a chiral smectic liquid crystal composition that is a compound represented by the following general formula II. [General formula II] A, b, and c each independently represent 0 or an integer of 1 to 3. However, a + b + c is at least 2. M, N
Are independently -COO-, -COS-, -COS
e -, - COTe -, - (CH 2 CH 2) d - (d is an integer of from 1 4), - C≡C -, - CH = CH -, -
CH = N—, —CH ₂ —O—, —CO—, —O—, a single bond, and the orientation may be any. X, Y and Z are each 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 each independently 0 to
Represents an integer of 4. G is _{-COO-C e H 2e -,} - O-C e
_{H 2e -, - O (C} e "H 2e" O) t -C e 'H 2e' -, -
_{C e H 2e -, - OSOO} -, - SOO -, - SOOC e H
_{2e -, - C e H 2e} -N (C p H 2p + 1) -SOO -, - C e
_{H 2e -N (C p H 2p} + 1) -CO- (e, e ' represents an integer of from 1 independently to 20, p is an integer from 0 to 4 .e "is respectively ( C _e "H _2e" O) independently represents an integer of 1 to 10, t is .A representative of the representative.) an integer from 1 to _{6 -O- (C f H 2f -O} ) u -C
_{f 'H 2f' + 1,} - (C f H 2f -O) u -C f 'H 2f' + 1, -
_{C f H 2f -R ', -} O-C f H 2f -R', - COO-C f
_{H 2f -R ', - OCO-} C f H 2f -R' (R ' is -C
_{l, -F, -CF 3, -NO} 2, -CN, -H, -COO
_{-C f 'H 2f' + 1} , represents _{-OCO-C f 'H 2f'} + 1,
f and f ′ each independently represent an integer of 1 to 20. u
Is an integer of 1 to 10. A represents a linear or branched chain. R is - (C _x F _2x O) a _{z C y F 2y + 1,} x is an integer from 1 independently each C _x F _2x O group until 10, integer y is from 1 to 10 And z is an integer from 1 to 10. ) 5. The liquid crystal device according to claim 4, wherein the compound represented by the general formula II is a liquid crystal composition comprising a phenylpyrimidine core. 6. A composition comprising a fluorocarbon end portion and a hydrocarbon end portion, and at least one ether oxygen in the chain in the fluorocarbon end chain, wherein both end portions are linked by a central nucleus, wherein the smectic mesophase or The liquid crystal device according to any one of claims 1 to 5, wherein a liquid crystal composition containing 50% by weight or more of a fluorine-containing liquid crystal compound having a latent smectic mesophase is used. 7. A liquid crystal device using the liquid crystal device according to any of claims 1-6.