JP2001316666A - Liquid crystal composition, liquid crystal element and liquid crystal apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal element, low in power consumption, high in luminance and performance. SOLUTION: In the liquid crystal layer of this liquid crystal element, a liquid crystal composition containing at least a discotheque liquid crystal and a stick- shaped liquid crystal is used. The discotheque liquid crystal and the stick-shaped liquid crystal exist in a phase-separation state. The discotheque liquid crystal exhibit a nematic discotheque phase.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal composition, a liquid crystal element, and a liquid crystal device useful as a functional material usable as a light valve for a flat panel display, a paper 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 used most widely.
CRTs are widely used as moving image outputs for televisions and VTRs, or as monitors for personal computers and the like. However, due to the characteristics of the CRT, flicker and scanning fringes due to insufficient resolution lower the visibility of a still image,
Degradation of the phosphor due to burn-in may occur. Also,
The power consumption is considerably large, and improvement is required in terms of power saving. Since the CRT must have a large volume behind the screen due to its structure, the convenience of the information device having the CRT is limited, and it is not suitable for saving space in offices and homes.

As a solution to such a problem of the CRT, there is a liquid crystal display element. For example, "Applied Physics Letters" by M. Schadt and W. Helfrich (Applied Physics L)
etters) Vol. 18, No. 4 (February 15, 1971
Published on pages 127-128, twisted nematic
A device using a liquid crystal is known. In recent years, this type or VA (vertical alignment)
Mode, IPS (inplane switching)
2. Description of the Related Art A liquid crystal element called a TFT using a liquid crystal of a mode or the like has been developed and commercialized. In this type, since a transistor is formed for each pixel, there is no problem of crosstalk.
0-13 inch displays are being produced with good productivity.

However, these liquid crystals are usually used as a display by using a backlight and modulating light transmitted through the liquid crystal element. For this reason, strong light is required as a backlight, and most of the power consumption of the liquid crystal display is consumed by the backlight. Even if a lithium ion secondary battery is used, the continuous operation time of a mobile device or the like is at most several hours. is there. Also, if backlighting of more liquid crystal elements can be realized, more information devices,
The power consumption of office equipment will be reduced, and it will contribute to the suppression of global warming and the preservation of the global environment.

Under these circumstances, a low power consumption type reflection type liquid crystal element which does not use a backlight is being developed. However, at present, its characteristics are still required to be improved. Further, products using a liquid crystal element as a projection type, a so-called projector, are marketed by various companies as large-screen displays. In this field, further improvements are required in terms of brightness and contrast. In response to such a demand, a scattering type liquid crystal element called a polymer dispersion type or a polymer network type liquid crystal has been proposed and studied, aiming at a high brightness liquid crystal element which does not require a polarizing plate (for example, 93 Euro
display 397). However, it is still desirable for these devices to have improved driving characteristics, scattering power and other characteristics.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above prior art, and it is an object of the present invention to provide a low power consumption, high luminance, high performance liquid crystal element, a light modulation element, and a display. It is intended to provide an element and a liquid crystal device. Another object is to provide a liquid crystal composition useful as an excellent functional material used for them.

[0007]

That is, the first invention of the present invention comprises at least a discotic liquid crystal and a rod-like liquid crystal, wherein the discotic liquid crystal and the rod-like liquid crystal exist in a phase-separated state, and A liquid crystal composition characterized in that the liquid crystal exhibits a nematic discotic phase.

It is preferable that the rod-like liquid crystal is a nematic liquid crystal. Preferably, the discotic liquid crystal comprises a polymer discotic liquid crystal obtained by polymerizing a polymerizable discotic liquid crystal compound. Preferably, the polymer discotic liquid crystal is obtained by polymerizing a polymerizable discotic liquid crystal compound by photopolymerization.

The second invention of the present invention contains at least a discotic liquid crystal and a rod-like liquid crystal, wherein the discotic liquid crystal and the rod-like liquid crystal exist in a phase-separated state, and the discotic liquid crystal shows a nematic discotic phase. A liquid crystal element characterized by using a liquid crystal composition for a liquid crystal layer.

It is preferable that the liquid crystal layer is provided on one substrate or between a pair of substrates which has been subjected to an alignment treatment. It is preferable that the discotic liquid crystal is edge-on uniaxially aligned. Preferably, the rod-shaped liquid crystal performs in-plane switching. It is preferable that the orientation director of the discotic liquid crystal and the orientation director of the rod-shaped liquid crystal are oriented in the same orientation.

It is preferable that the discotic liquid crystal alignment director and the rod-shaped liquid crystal alignment director are aligned in an orthogonal state. Preferably, the liquid crystal element is a polymer dispersed liquid crystal element. It is preferable that the liquid crystal element is a reflection type liquid crystal element that uses reflected light of the liquid crystal element as a display signal. It is preferable that the liquid crystal element has a light absorbing plate or a reflecting plate provided on the back surface of the liquid crystal layer. The liquid crystal element is preferably a projection type liquid crystal element.

A third invention of the present invention is a liquid crystal device using the above liquid crystal element.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION As a result of intensive studies, the present inventors have found that a liquid crystal composition in which a discotic liquid crystal and a rod-like liquid crystal exist in a phase-separated state and the discotic liquid crystal exhibits a nematic discotic phase. Liquid crystal devices utilizing, in particular, devices in which discotic liquid crystals are edge-on uniaxially aligned, and devices in which rod-shaped liquid crystals are in-plane switched, have low power consumption, high brightness, high performance liquid crystal devices, light modulation devices, and display devices. Have been realized, and the present invention has been completed.

Hereinafter, the present invention will be described in detail. A first invention of the present invention is a liquid crystal composition in which a discotic liquid crystal and a rod-like liquid crystal exist in a phase separated state, and the discotic liquid crystal exhibits a nematic discotic phase. Conventionally, as disclosed in Japanese Patent Application No. Hei 11-133654, a scattering type liquid crystal element using a discotic polymer and a rod-shaped liquid crystal was invented by the present inventor. There has been a demand for a method of controlling the alignment at a higher order, and it has been required to exhibit a phase separation state between a nematic discotic phase and a rod-shaped liquid crystal, which is the easiest to control the alignment among the discotic liquid crystals.

In this regard, the liquid crystal composition of the present invention in which the discotic liquid crystal and the rod-like liquid crystal exist in a phase-separated state and the discotic liquid crystal exhibits a nematic discotic phase is a useful functional material. As a method for obtaining this functional material, preferably, a discotic liquid crystal material and a rod-shaped liquid crystal that can exhibit a nematic discotic phase are used, and especially when a rod-shaped liquid crystal is considered as a switching liquid crystal, a nematic liquid crystal is preferable. It can be obtained by finding the composition ratio where the phase and the rod-like liquid crystal phase are mixed. In a composition with any rod-like liquid crystal in a discotic liquid crystal that does not show any nematic discotic phase, this state is not found, and it is preferable to use a material that shows a nematic discotic phase in a wider temperature range. At the same time, it is preferable to use a rod-like nematic liquid crystal which exhibits a nematic liquid crystal phase in a wider temperature range. It is also preferable to promote the phase separation. When a fluorine liquid crystal is used as the nematic liquid crystal, it is preferable to use a material having incompatible properties, that is, a so-called reciprocal material, as when a non-fluorine liquid crystal is used as the discotic liquid crystal. More desirably, it is usually difficult to maintain such a phase-separated state in a wide temperature range. Therefore, it is preferable to fix one of the liquid crystals by polymerizing the liquid crystal. By doing so, the phase separation between the polymerized liquid crystal phase and the remaining liquid crystal phase is further promoted, re-dissolution at a high temperature is suppressed, and the phase separation state of the present invention is maintained over a wide temperature range.

Since it is often assumed that a rod-shaped liquid crystal is used as the switching liquid crystal, it is preferable to polymerize the discotic liquid crystal and fix the state of the nematic discotic liquid crystal. A method is often used in which a polymerizable discotic liquid crystal material is used, and the above-described phase separation state is formed, then polymerized by photopolymerization or the like, and fixed. At that time, a polymerization initiator, a stabilizer and the like may be added.

Specific examples which can be used as a discotic liquid crystal compound are shown below. Of course, the present invention is not limited to these specific examples.

[0018]

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[0019]

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[0020]

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[0021]

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[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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[0027]

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[0028]

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As the rod-like liquid crystal, a nematic liquid crystal or a smectic liquid crystal is preferably used, but a nematic liquid crystal is preferable in terms of productivity, cost and switching characteristics. Numerous commercially available nematic liquid crystals can be used. As the smectic liquid crystal, an SA liquid crystal, a ferroelectric liquid crystal, an antiferroelectric liquid crystal, a chiral smectic liquid crystal, or the like can be used.

The liquid crystal composition of the present invention in which the discotic liquid crystal and the rod-shaped liquid crystal exist in a phase-separated state and the discotic liquid crystal exhibits a nematic discotic phase is used in addition to the discotic liquid crystal in this state. After controlling the orientation in the nematic discotic phase, it is further transformed to a higher-order discotic phase, and when the orientation-controlled state of the higher-order discotic is used, it is possible to use it in various ways. Usage is possible.

The composition of the discotic liquid crystal and the rod-like liquid crystal in which the discotic liquid crystal and the rod-like liquid crystal exist in a phase-separated state and the discotic liquid crystal exhibits a nematic discotic phase is usually 1% by weight of the discotic liquid crystal. 99 wt% or less, rod-shaped liquid crystal is 1 wt%
% To 99% by weight, preferably 5% to 95% by weight of discotic liquid crystal, and 5% by weight of rod-shaped liquid crystal.
It is not less than wt% and not more than 95 wt%. Of course, as described above, it is also possible to contain additives such as a polymerization initiator, a stabilizer, an antioxidant, a viscosity reducing agent, and a dye.

Next, a liquid crystal device according to a second invention of the present invention will be described. Hereinafter, an example of the liquid crystal element of the present invention will be described.

FIG. 1 shows an example of a liquid crystal element using a discotic liquid crystal polymer and a rod-shaped liquid crystal. In FIG. 1, 1 is a liquid crystal layer, and a polymer network is formed,
It is composed of a polymeric discotic liquid crystal compound.
Separately, rod-shaped liquid crystal usually exists as a liquid crystal capable of responding to an electric field. The alignment state of the rod-shaped liquid crystal can be changed by the electric field. The cell thickness of the liquid crystal layer 1 is preferably selected between 1 μm and 100 μm. This gap is usually controlled using the spacer 5. 2a,
2b is a substrate made of glass, plastic, or the like. 3a and 3b are transparent electrodes such as ITO. 4a, 4
b is the orientation control layer, but need not be. In addition, a short prevention layer, a light absorption layer, a reflection layer, and a color filter layer can be provided. When used as a scattering element or a reflection element, one of the upper and lower substrates may not be present, and the upper and lower substrates may be asymmetric.

Further, a preferred example of the liquid crystal device of the present invention will be described. In FIG. 1, a polyimide rubbing alignment film is used for the alignment control layers 4a and 4b. When a polymerizable discotic liquid crystal exhibiting a nematic discotic phase and a rod-shaped liquid crystal in a phase-separated state are used in the liquid crystal layer, the nematic discotic phase is edge-on uniaxially oriented by the orientation control layer. In this state, when the rod-shaped liquid crystal is switched so that its alignment director is perpendicular to the alignment director of the discotic liquid crystal in a plane parallel to the substrate, a mismatch in the refractive index with respect to light from the upper surface of the substrate occurs. In all cases, the alignment state is suppressed and the light is well transmitted. On the other hand, when the alignment director of the rod-shaped liquid crystal is switched so as to be parallel to the alignment director of the discotic liquid crystal, the mismatching of the refractive index becomes an alignment state that becomes extremely large in each direction, and the light is scattered well. . By using one or both of these two states, a switching element based on reflected light control becomes possible.

In order to perform the above switching, it is necessary to perform so-called in-plane switching of a rod-like liquid crystal. A comb-shaped electrode to which a horizontal electric field can be applied is provided, or a ferroelectric liquid crystal which performs in-plane switching by upper and lower electrodes is used. It becomes necessary to do. FIG. 2 is a schematic diagram illustrating the above-described switching by an index ellipsoid.

Of the two alignment states in FIG. 2, the state in which the alignment director of the rod-shaped liquid crystal and the alignment director of the discotic liquid crystal are parallel is that light scattering intensity can be increased as described in detail below. Particularly preferably used. FIG. 2 shows a refractive index director in each liquid crystal model. In the rod-shaped liquid crystal 7a, the two refractive indexes n ₁ and n ₂ in the short axis direction are smaller than the refractive index n ₃ in the long axis direction. In the case of a nematic liquid crystal, n ₁ and n ₂ are equal. On the other hand, in the case of the discotic liquid crystal 8a, a so-called amppan-type refractive index ellipsoid is formed. That is, n _d1 and n _d2 are large and n _d3 is small. It is possible to describe the strong light scattering ability of the present invention using typical values of the refractive index in each direction of the rod-shaped liquid crystal and the discotic liquid crystal. The typical values are shown in Table 1 together with typical values of the matrix polymer used in the ordinary polymer-dispersed liquid crystal.

[0037]

[Table 1]

The light scattering ability depends on the difference in the refractive index of the medium.
To do so was mentioned earlier. In the case of ordinary polymer dispersed liquid crystal,
One direction (n_Three= 1.7) only high refractive index
It can be seen from the table that a difference from the refractive index of the
Thus, in the present invention, n _d1And n₁, N_d2And n_Two, N_d3
And n_ThreeWith the combination of
Then, it is understood that a difference in refractive index occurs in all directions.
When discotic liquid crystal and rod-shaped liquid crystal are in phase separation state
Discotic and liquid crystal domains
Light scattering occurs at the interface with the
If the orientation directors are in the same direction,
The difference in the refractive index in each direction of the crystal
To grow bigger. The light scattering intensity of the phase-separated light scattering medium is
In the polymer dispersion type liquid crystal which is a typical example of
The greater the difference in refractive index between different phases, the stronger
It is known. As this shows, FIG.
Director of aligned discotic and rod-shaped liquid crystals
Are in the same direction, that is, in each direction of each liquid crystal.
State in which the difference in the refractive index is maximized in any direction
Can produce a very large light scattering state.
available. The present inventor has conducted intensive studies and found that nematic
Discotic liquid crystals and rod-like liquids exhibiting discotic phases
Crystals are in a phase separated state and the alignment
Successfully form a state in which the
The appearance of strong light scattering in the state could be confirmed.

In order to stably use the discotic liquid crystal and the rod-shaped liquid crystal in a phase-separated state in a wider temperature range, one of the liquid crystals, preferably the discotic liquid crystal is polymerized, and a so-called polymer dispersed liquid crystal is used. It is better to do. As described above, a polymer-dispersed liquid crystal can be easily obtained by photopolymerizing a polymerizable discotic liquid crystal. It is also possible to use a polymer discotic liquid crystal which is originally a polymer. Examples of the polymer discotic liquid crystal compound include, for example, JP-A-8-27284, “Macromol.
pid Commun. "18, 93-98, 1
997, or "EKISHO" Vol. 1, p. 45, 1
997.

In the above-described reflected light control type liquid crystal element, a liquid crystal element having extremely excellent luminance without using a backlight which is a large power consumption source can be manufactured. Further, a light absorbing plate or a reflecting plate (for example, “I
DRC "'94, p. 183.), the contrast and the brightness can be made more preferable. This reflection type liquid crystal element is a direct-view type liquid crystal using an external light or an auxiliary light source. It can also be used as a display element.

Further, the present invention can be used as a so-called projection type liquid crystal element in which strong light is incident from the front surface, and light modulated and reflected by the liquid crystal element is projected on a screen after controlling the optical path.

On the other hand, a projection type liquid crystal element, that is, a projection type liquid crystal element, can be used as a transmission type liquid crystal element instead of a reflection type liquid crystal element. FIG. 3 is a schematic view showing an example of a typical transmission type projection liquid crystal element. In FIG. 3, 303, 303 ′, 303 ″
A color image can be projected on a projection screen by using a liquid crystal element having a matrix pattern such as an active matrix element described later for a liquid crystal element corresponding to each of the three primary colors. In this case, the liquid crystal element of the present invention performs black display in a scattering state, and a higher contrast can be realized in the liquid crystal element of the present invention in which stronger scattering can be obtained.

Further, the liquid crystal element of the present invention can be a high definition and high performance liquid crystal element by using an active element. This will be described below.
For example, the active matrix element shown in FIG. 4 using the configuration described above as one pixel is exemplified. In FIG. 4, a transparent pixel electrode 43 and an active element 44 connected to the pixel electrode 43 are formed in a matrix on a lower substrate 41 of a pair of transparent substrates (eg, glass substrates) 41 and 42. I have. The active element 44 is composed of, for example, a thin film transistor called a TFT. As the transistor, a semiconductor such as an amorphous silicon base, a polysilicon type, a μ crystal base, or a single crystal silicon can be used. In this example, reference numeral 44 denotes a TFT. 44 includes a gate electrode formed on the substrate 41, a gate insulating film covering the gate electrode, a semiconductor layer formed on the gate insulating film, and a source electrode and a drain electrode formed on the semiconductor layer. .

Further, on the lower substrate 41, gate lines (scan lines) 45 are arranged between the rows of the pixel electrodes 43 as shown in FIG. 5, and information signal lines 46 are arranged between the columns of the pixel electrodes 43. The gate electrode of each TFT 44 is connected to a corresponding gate line 45, and the drain electrode is connected to a corresponding information signal line 46. Gate line 4
5 is connected to a row driver via an end 45a, and the information signal line 46 is connected to a column driver via an end 46a. The row driver scans the gate line 45 by applying a gate signal. The column driver applies a signal corresponding to the display data. The gate line 45 is covered with the gate insulating film of the TFT 44 except for the end 45a, and the information signal line 46 is formed on the gate insulating film. The pixel electrode 43 is formed on the gate insulating film, and has one end connected to the source electrode of the TFT 44. Further, a transparent electrode 47 facing each pixel electrode 43 of the lower substrate 41 is formed on the upper substrate 42 in FIG. The counter electrode 47 is composed of one electrode having an area covering the entire display area, and a reference voltage is applied thereto. The transmittance changes according to the information signal voltage, and gradation expression can be performed. In addition, a capacitor serving as an auxiliary capacitance is often arranged for each pixel.

In the active element described above,
When the gate is on, charge is injected into the liquid crystal cell as a pixel, the gate is turned off in a short time, and information is written to the pixel on the next scan line.

The liquid crystal element of the present invention can be used as a light valve of a printer or the like. The liquid crystal element of the present invention can constitute a liquid crystal device having various functions. For example, mobile, PDA, desktop PC,
Examples include a laptop PC, a video camera, a digital camera, a document viewer, a printer, a copying machine, and the like.

In the liquid crystal device of the present invention, the liquid crystal element as a medium has good switching characteristics as described above.
It exhibits excellent driving characteristics and reliability, and can realize a high-definition, high-speed, large-area display image.

[0048]

Next, the present invention will be described more specifically with reference to examples and comparative examples. Note that the present invention is not limited to these examples.

Example 1 <Used polymerizable discotic liquid crystal compound A> As the polymerizable discotic liquid crystal compound, a compound A represented by the following structural formula was used.

[0050]

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A represents that the molar ratio of R ₁ / R ₂ is 5/1 and 4 /
What is 2 and 3/3 is a mixture of 22:59:16. The phase transition of A is discotic rectangular phase- (131 ° C.)-Nematic discotic phase- (2
00 ° C.)-Iso (heating process).

<Rod-shaped nematic liquid crystal B> Nematic liquid crystal "KN5027" manufactured by Chisso was used. Δn is 0.1
It was 6. The dielectric anisotropy was positive and was 8. B has a phase transition of Cryst. -(<-30 ° C) -N phase- (81 ° C)-
Iso (temperature rising process).

Using these, A and B were mixed at a weight mixing ratio of A /
B = 50/50 (mixture) to prepare a mixture of a polymerizable discotic liquid crystal compound and a rod-shaped liquid crystal.
The mixture dissolved in an isotropic state.

<Preparation of Cell> Cell α An approximately 70 nm-thick ITO film capable of applying an electric field with a single substrate was formed in a comb-like shape on a glass substrate (using two sheets) having a thickness of 1.1 mm. The width of the electrodes was 15 μm, and the distance between the electrodes was 50 μm.

The above two substrates with ITO were used, and 4 w of polyimide JALS2022 manufactured by Nippon Synthetic Rubber Co., Ltd.
t% solution for 1 second at 500 rpm for 5 seconds
Spin coating was performed at 500 rpm for 30 seconds. Then, after pre-drying at 80 ° C. for 5 minutes,
Heat baking was performed for hours. Rubbing treatment was performed on each of the substrates so as to be perpendicular to the comb electrodes.

An IPA solution in which resin beads having an average particle diameter of 10 μm are dispersed at 0.01% by weight is spin-coated on the surface of one of the substrates under the conditions of 1500 rpm and 10 sec, and a bead spacer having a dispersion density of about 100 / mm ^2. Was sprayed. A thermosetting liquid adhesive was applied to the substrate by a printing method. The two substrates obtained by rubbing were bonded together with their rubbing axes aligned and heated and cured in an oven at 150 ° C. for 90 minutes to obtain cells. The electric field application direction of the lower substrate was made parallel to the rubbing, and the electric field application direction of the upper substrate was made perpendicular to the rubbing.

To the above mixture, 2,6-ditert-butyl-4-methylphenol was added in an amount of 200 ppm.
After addition of 2 wt% of a photopolymerization initiator Irgacure 184 manufactured by Ciba Geigy, the cell α in an isotropic phase was added.
At normal pressure. When the cell was cooled at 10 ° C./min, it was observed that at 20 ° C., the nematic discotic phase and the nematic liquid crystal appeared in a phase-separated manner. When held in this state for 10 minutes, it was found that the nematic discotic phase transmitted strong polarized light and was uniformly edge-on uniaxially oriented under a polarizing microscope. Here, about 12 mW / cm ² and center wavelength 365 nm
After exposure for one minute, the nematic discotic phase was polymerized.

According to observation under a polarizing microscope in a hot stage manufactured by Mettler Co., the state after the polymerization was maintained at 20 ° C. for 10 minutes was maintained in a wide temperature range. Even at 200 ° C., the texture of the discotic liquid crystal was maintained.

When an AC electric field of 110 V and 1 kHz was applied to the lower substrate while the electrode of the upper substrate was left open to the cell α, the nematic liquid crystal was oriented in parallel to the direction in which the electric field was applied. It was found that the visual scattering state was greatly increased. This state is a state where the discotic alignment director and the nematic alignment director in FIG. 2 are in the same direction.

Comparative Example 1 Hexylene diacrylate was changed to polymerizable discotic liquid crystal A, and a nematic liquid crystal "KN5" manufactured by Chisso Corporation was used.
027 "to prepare a mixture at a weight ratio of 50/50. This was injected into the cell α in the same manner as described above, and subjected to UV exposure in the same manner as described above, thereby producing a polymer-dispersed liquid crystal element.

A black light absorbing plate was placed on the back of the cell prepared above, and the reflected light intensity was measured with an automatic polarization photometer GP-200 manufactured by Murakami Color Research Laboratory. Incident angle 3
At 0 degree, the light intensity in the direction of the emission angle of 0 degree was compared between the cell of Comparative Example 1 and the cell of Example 1. The cell of Example 1 is 110 V, lk
The comparison was performed in a state where an electric field of Hz was applied. Compared to the cell of the comparative example, the cell α of the mixture reflected light of 3.4 times the intensity.

Example 2 The lower substrate was opened in the cell prepared in Example 1, an electric field of 110 V and 1 kHz was applied to the upper substrate, and the intensity of reflected light when the same electric field was applied to the lower substrate was measured. The measurement was performed in the same manner as the measurement performed in the above section and compared. It was found that the case where the electric field of 110 V and 1 kHz was applied to the upper substrate and the case where the same electric field was applied to the lower substrate had a clear contrast of 1.0 to 1.43 in reflected light intensity.

[0063]

As described above, according to the liquid crystal device of the present invention, a liquid crystal device, a light modulation device, and a display device having higher luminance and higher performance than conventional liquid crystal devices can be realized. Further, the present invention can realize a liquid crystal device using a high-brightness, high-performance liquid crystal element.

[Brief description of the drawings]

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

FIG. 2 is an explanatory view showing an alignment director of a rod-shaped nematic liquid crystal and a discotic liquid crystal.

FIG. 3 is a schematic view showing an example of a typical transmission type projection liquid crystal element.

FIG. 4 is a schematic diagram illustrating an example of an active matrix element.

FIG. 5 is a schematic diagram illustrating an example of an active matrix element.

[Explanation of symbols]

 Reference Signs List 1 liquid crystal layer 2a, 2b substrate 3a, 3b transparent electrode 4a, 4b alignment control layer 5 spacer 7 rod-shaped liquid crystal part 7a rod-shaped liquid crystal 8 discotic liquid crystal part 8a discotic liquid crystal 18 alignment film 19 alignment film 20 sealant 21 liquid crystal 22 Spacer beads 23 Protective plate 24 Protective plate 31 Row driver 32 Column driver 41 Lower transparent substrate 42 Upper transparent substrate 43 Pixel electrode 44 Active element (TFT) 45 Gate line (scan line) 46 Data line (gradation signal line) 47 Opposite Electrode 301 Light source unit 302, 302 ', 302 "Dichroic mirror 303, 303', 303" Liquid crystal element 304, 304 ', 304 "Schlieren optical system 305 Dichroic prism 306 Projection lens 307 Liquid crystal element driving device

Claims (15)

[Claims] 1. A liquid crystal composition comprising at least a discotic liquid crystal and a rod-like liquid crystal, wherein the discotic liquid crystal and the rod-like liquid crystal exist in a phase-separated state, and the discotic liquid crystal exhibits a nematic discotic phase. object. 2. The liquid crystal composition according to claim 1, wherein the rod-shaped liquid crystal is a nematic liquid crystal. 3. The liquid crystal composition according to claim 1, wherein the discotic liquid crystal comprises a polymer discotic liquid crystal obtained by polymerizing a polymerizable discotic liquid crystal compound. 4. The liquid crystal composition according to claim 3, wherein the polymer discotic liquid crystal is obtained by polymerizing a polymerizable discotic liquid crystal compound by photopolymerization. 5. A liquid crystal layer containing at least a discotic liquid crystal and a rod-like liquid crystal, wherein the discotic liquid crystal and the rod-like liquid crystal exist in a phase-separated state, and the discotic liquid crystal exhibits a nematic discotic phase. A liquid crystal element characterized by being used. 6. The liquid crystal device according to claim 5, wherein the liquid crystal layer is provided on one substrate or between a pair of substrates that has been subjected to an alignment treatment. 7. The discotic liquid crystal according to claim 1, wherein
The liquid crystal element according to claim 5, wherein the liquid crystal element is aligned on uniaxially. 8. The liquid crystal device according to claim 5, wherein the rod-shaped liquid crystal performs in-plane switching. 9. The liquid crystal device according to claim 5, wherein the alignment director of the discotic liquid crystal and the alignment director of the rod-shaped liquid crystal are aligned in the same direction. 10. The liquid crystal device according to claim 5, wherein the alignment director of the discotic liquid crystal and the alignment director of the rod-shaped liquid crystal are aligned in an orthogonal state. 11. A polymer dispersed liquid crystal device.
11. The liquid crystal device according to any one of items 10 to 10. 12. The liquid crystal device according to claim 5, wherein the liquid crystal device is a reflection type liquid crystal device that uses light reflected by the liquid crystal device as a display signal. 13. The liquid crystal device according to claim 112, wherein a light absorbing plate or a reflecting plate is provided on a back surface of the liquid crystal layer. 14. A projection-type liquid crystal element.
3. The liquid crystal device according to any one of items 3. 15. A liquid crystal device using the liquid crystal element according to claim 5.