JP2002285159A - Liquid crystal composition and liquid crystal optical modulator using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid crystal composition which has low viscosity, high refractive index anisotropy, high dielectric constant anisotropy and a high phase transfer temperature, can enhance a responsing speed, can lower a driving voltage, and can improve contrast, and to obtain a liquid crystal optical modulator. SOLUTION: A liquid crystal display element nips a liquid crystal composition exhibiting a cholesteric phase at room temperature between resin substrates 11, 12 having transparent electrodes 13, 14, respectively. This liquid crystal composition contains a nematic liquid crystal mixture containing at least a liquid crystalline tolane compound, a liquid crystalline terphenyl compound and a liquid phenylcyclohexyl compound as main components or a nematic liquid crystal mixture containing at least a liquid crystalline ester compound, a liquid crystalline terphenyl compound and a liquid phenylcyclohexyl compound as main components, and further contains at least one chiral material in an amount of 10 to 45 wt.%.

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 and a liquid crystal light modulation device such as a liquid crystal display device using the composition.

[0002]

2. Description of the Related Art In recent years, various studies have been made on reflection type liquid crystal display devices using a chiral nematic liquid crystal, which exhibits a cholesteric phase at room temperature by adding a chiral material to the nematic liquid crystal. In this element, display is performed by switching a liquid crystal between a planar state (colored state) and a focal conic state (transparent state) by applying pulse signals having different energies. It is also possible to configure so that the colored / transparent state can be maintained even after the application of the voltage is stopped.

[0003] This type of liquid crystal is expected to be used in a region different from that of a monitor liquid crystal for displaying moving images. A typical use is as a substitute for paper for printing image and character information, and for example, an electronic blackboard, an advertising board, an electronic book terminal, a decorative panel, and the like can be considered.

However, to date, reflection-type liquid crystal display devices using chiral nematic liquid crystals have insufficient Y value (luminous reflectance), resulting in low contrast, low response speed, low voltage drive, and high temperature stability. Was not satisfactory.

Accordingly, an object of the present invention is to achieve a high response speed, a low drive voltage, and a high contrast with low viscosity, high refractive index anisotropy, dielectric anisotropy and high phase transition temperature. To provide a liquid crystal composition and a liquid crystal light modulation device that can be used.

[0006]

In order to achieve the above objects, the liquid crystal composition according to the first invention comprises at least a liquid crystal trans compound, a liquid crystal terphenyl compound and a liquid crystal phenylcyclohexyl compound. It is characterized by containing a nematic liquid crystal mixture and at least one kind of chiral material in an amount of 10 to 45% by weight and exhibiting a cholesteric phase at room temperature.

A liquid crystal light modulation device according to a second invention is characterized in that at least one of the liquid crystal compositions according to the first invention is sandwiched between a pair of transparent substrates.

The liquid crystal composition according to the third invention comprises a nematic liquid crystal mixture containing at least a liquid crystal ester compound, a liquid crystal terphenyl compound and a liquid crystal phenylcyclohexyl compound, and at least one kind of chiral material. ４５45 wt%, showing a cholesteric phase at room temperature.

A liquid crystal light modulation device according to a fourth invention is characterized in that at least one of the liquid crystal compositions according to the third invention is held between a pair of transparent substrates.

In a liquid crystal composition exhibiting a cholesteric phase at room temperature, a plurality of pulse voltages having different energies are applied to the composition, whereby the liquid crystal selectively emits light having a peak at a specific wavelength. A state of reflection and a transparent state of transmitting incident light are switched.

The liquid crystalline tolan compound and the liquid crystalline phenylcyclohexyl compound have relatively large refractive index anisotropy.
Since the viscosity is low, there is an advantage that the driving voltage can be reduced, the response speed is improved, and since the reflectance at the time of coloring is large, the contrast is also increased. In particular, the liquid crystalline phenylcyclohexyl compound has a high Y value and a high colored Y value in a transparent state, improves contrast, and provides stability of display characteristics. Further, the viscosity is reduced, so that the drive voltage can be reduced and the reliability of the element can be improved.

The liquid crystalline terphenyl compound is excellent in light stability and chemical stability, and has a large refractive index anisotropy and a high phase transition temperature, thereby contributing to expansion of the temperature compensation range.
Further, the Y value at the time of coloring is high and the contrast is improved. In particular, an F group, a Cl group,
By providing a polar group such as a CN group, the dielectric anisotropy increases and the driving voltage decreases.

The liquid crystalline ester compound has a large dielectric anisotropy and contributes to a reduction in driving voltage. In particular, the F group, Cl
A liquid crystal ester compound having a large polarity structure provided with a group and a CN group can be driven at a lower voltage. However,
Liquid crystal ester compounds generally have high viscosity and have a disadvantage that response speed is slow. In particular, 10
The chiral nematic liquid crystal composition containing not less than wt% has a problem that the viscosity is further increased. Further, the liquid crystal ester compound generally has a small refractive index anisotropy and cannot obtain a sufficient contrast. Therefore, good characteristics can be obtained by mixing a liquid crystalline phenylcyclohexyl compound having a low viscosity and high refractive index anisotropy with a liquid crystalline terphenyl compound having a large refractive index anisotropy and capable of expanding the temperature compensation range. .

In the liquid crystal composition according to the first aspect, the total content of the liquid crystalline tolan compound, the liquid crystalline terphenyl compound and the liquid crystalline phenylcyclohexyl compound is preferably at least 50 wt% of the total nematic liquid crystal mixture. . In particular, the content of the liquid crystalline tolan compound is preferably at least 10 wt% based on the nematic liquid crystal mixture. The content of the liquid crystalline terphenyl compound is preferably 30% by weight or more based on the nematic liquid crystal mixture. The content of the liquid crystalline phenylcyclohexyl compound is preferably at least 10% by weight based on the nematic liquid crystal mixture.

In the liquid crystal composition according to the third invention, the total content of the liquid crystal ester compound, the liquid crystal terphenyl compound and the liquid crystal phenylcyclohexyl compound is preferably at least 50 wt% of the total nematic liquid crystal mixture. In particular, the content of the liquid crystalline ester compound is preferably 30% by weight or more based on the nematic liquid crystal mixture. The content of the liquid crystalline terphenyl compound is preferably at least 10 wt% based on the nematic liquid crystal mixture. The content of the liquid crystalline phenylcyclohexyl compound is preferably at least 10% by weight based on the nematic liquid crystal mixture.

The content of the chiral material in the liquid crystal composition is preferably 10 to 45% by weight based on the total amount of the liquid crystal composition. By setting the content of the chiral material in this range, the selective reflection wavelength can be set to a desired wavelength range without causing precipitation of crystals. The chiral material is preferably added in combination of two or three kinds having the required properties. In addition, the liquid crystal composition may contain a dye. By adding a dye, the color purity and the like of the liquid crystal composition can be adjusted.

In the liquid crystal light modulating elements according to the second and fourth inventions, the liquid crystal composition is sandwiched between a pair of transparent substrates, at least one of which is transparent. It can be driven with low voltage and good response, and has a wide temperature compensation range.

An electrode may be formed on a substrate, and an organic film having functions such as an alignment control film and a color filter may be further provided thereon. By providing such an organic film, it is possible to enhance the operation stability and the light modulation function of the liquid crystal composition.

A structure comprising a plurality of polymer compounds may be provided between a pair of substrates. By providing such a structure, the distance between the substrates can be more accurately maintained,
It becomes easier to obtain the desired light modulation characteristics.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the liquid crystal composition and the liquid crystal light modulation device according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a sectional structure of a liquid crystal display device according to a first embodiment of the present invention.
Numerals 11 and 12 denote transparent substrates constituting a cell, each having a transparent electrode 1 formed in a plurality of strips parallel to each other.
3 and 14 are provided. Transparent electrode 13 and transparent electrode 1
4 are opposed to each other so as to cross each other. An insulating thin film 15 is coated on the electrode 13. 20 is a polymer structure as a space holding member, 2
1 is a liquid crystal composition showing a cholesteric phase at room temperature,
These materials and combinations thereof will be specifically described with reference to the following experimental examples. Reference numeral 22 denotes a sealing material for sealing the liquid crystal composition 21 inside the cell. Further, on the back surface of the substrate 12, a visible light absorbing layer 19 is provided as necessary for display. Instead of providing the light absorbing layer 19, a substrate having a visible light absorbing property may be used.

(Second Embodiment, see FIG. 2) FIG. 2 shows a sectional structure of a liquid crystal display element according to a second embodiment of the present invention.
This liquid crystal display element has basically the same structure as that of the first embodiment shown in FIG. 1, and does not include a polymer structure in a display area. In FIG. 2, FIG.
The same reference numerals are given to the same members. The liquid crystal display device having such a configuration is advantageous in that the aperture ratio is improved and the manufacturing process is simplified.

FIG. 3 shows a cross-sectional structure of a liquid crystal display device according to a third embodiment of the present invention.
This liquid crystal display device is characterized in that the second
It has basically the same structure as that of the embodiment, and has an orientation control film 17 formed on the electrode 14 of the substrate 12. 3, the same members as those in FIG. 2 are denoted by the same reference numerals.
In the liquid crystal display device having such a configuration, the anchoring effect can be provided to the liquid crystal molecules to some extent due to the presence of the alignment control film 17 as compared with the liquid crystal display device of FIG. This is advantageous in that it can be prevented from being changed in the future.

FIG. 4 shows a cross-sectional structure of a liquid crystal display device according to a fourth embodiment of the present invention.
This liquid crystal display element has basically the same structure as that of the third embodiment.
Also, an alignment control film 16 is formed on an insulating film 15. 4, the same members as those in FIG. 3 are denoted by the same reference numerals. In a liquid crystal display device having such a configuration, FIG.
This is advantageous in that the characteristics of the liquid crystal display element can be more effectively prevented from changing over time as compared with the liquid crystal display element.

(Fifth Embodiment, see FIG. 5) FIG. 5 shows a sectional structure of a liquid crystal display element according to a fifth embodiment of the present invention.
This liquid crystal display element has basically the same structure as that of the second embodiment, in which a color filter 18 is formed on an electrode 13 of a substrate 11. 5, the same members as those in FIG. 2 are denoted by the same reference numerals. The liquid crystal display device having such a configuration is advantageous in that scattering components other than the selectively reflected light can be eliminated as compared with the liquid crystal display device of FIG. 2, and the display quality of the liquid crystal display device can be improved. .

FIG. 6 shows a sectional structure of a liquid crystal display device according to a sixth embodiment of the present invention.
This liquid crystal display device is a full-color reflection type liquid crystal display device in which a liquid crystal composition 21 in which three layers have different selective reflection wavelengths is sandwiched. Each layer is adhered by a transparent adhesive 23. The selective reflection wavelength of the liquid crystal composition 21 of each layer is, in order from the observer side, about 490 nm (blue) for the first layer, about 560 nm (green) for the second layer, and about 680 nm (red) for the third layer. Has been adjusted.

This liquid crystal display element converts image data into RGB data.
By switching the liquid crystal display elements of each layer to a planar state, a focal conic state, and an intermediate state between the focal conic state and the planar state based on the respective color image data decomposed into, a good full-color display element can be performed. it can.

FIG. 7 shows a cross-sectional structure of a liquid crystal display device according to a seventh embodiment of the present invention.
This liquid crystal display device is a color reflective liquid crystal display device in which a liquid crystal composition 21 in which two layers have different selective reflection wavelengths is sandwiched. Each layer is adhered by a transparent adhesive 23. The selective reflection wavelength of the liquid crystal composition 21 of each layer is not particularly limited. For example, the first layer is adjusted to around 490 nm (blue) and the second layer is adjusted to around 560 nm (green) from the observer side. .

(Eighth Embodiment, see FIG. 8) FIG. 8 shows a cross-sectional structure of a liquid crystal display element according to an eighth embodiment of the present invention.
In this liquid crystal display element, a network polymer matrix 24 is formed between the substrates 11 and 12, and the space between the polymer matrices 24 is filled with a liquid crystal composition. Other configurations are basically the same as those of the second embodiment. The liquid crystal display device having such a configuration is advantageous in that the area can be easily increased and the viewing angle characteristics can be improved.

(Ninth Embodiment, see FIG. 9) FIG. 9 shows a cross-sectional structure of a liquid crystal display device according to a ninth embodiment of the present invention.
This liquid crystal display element has basically the same structure as that of the second embodiment. Between the substrates 11 and 12, the ultraviolet curable polymer monomer mixed in the chiral nematic liquid crystal composition 21 is cured by ultraviolet irradiation. , Polymer structure 25
Is a liquid crystal display element having a polymerized phase separation type structure.

FIG. 10 shows a cross-sectional structure of a liquid crystal display device according to a tenth embodiment of the present invention. This liquid crystal display device is a full-color reflective liquid crystal display device in which three layers sandwich a liquid crystal composition 21 having different selective reflection wavelengths, similarly to the sixth embodiment. The substrate 12 'between the first layer and the second layer and the substrate 11' between the second layer and the third layer are composed of one substrate, and the transparent electrode on the substrate, the insulation The structure of the conductive thin film and the like is basically the same as that of the second embodiment. In the liquid crystal display device having such a configuration, the number of substrates is small as a whole, and it is not necessary to consider display deterioration due to the transparent adhesive 23 (see FIG. 6). Further, it is advantageous in that the aperture ratio is improved and the manufacturing process is simplified.

(Display Method) In each of the liquid crystal display elements having the above configuration, display is performed by applying a pulse voltage to the electrodes 13 and 14. That is, when the liquid crystal composition 21 uses a material exhibiting a cholesteric phase, by applying a pulse voltage of relatively high energy, the liquid crystal is in a planar state, and is determined based on a helical pitch and a refractive index of liquid crystal molecules. Light of a wavelength is selectively reflected. By applying a pulse voltage of relatively low energy, the liquid crystal is in a focal conic state and is in a transparent state. It is also possible to configure so that each state is maintained even when no voltage is applied.

It has been found that there is also an intermediate state between the focal conic state and the planar state. By applying a pulse voltage of intermediate energy, it is possible to express a halftone. In the intermediate state, the focal conic state and the planar state are considered to be mixed, and this state can be configured to be maintained when no voltage is applied. When the visible light absorbing layer 19 is provided, black is displayed in the focal conic state.

In the present liquid crystal display device, strip-shaped electrodes 13 and 14 are used.
, The intersection area becomes a display pixel. In this specification, a region in which light modulation is performed by the liquid crystal is referred to as a light modulation region, and its periphery is outside the light modulation region in which light modulation is not performed. In a liquid crystal display device, a light modulation region is a display region.

(Substrate) At least one of the substrates 11 and 12 needs to have optical transparency. As the transparent substrate, a glass substrate, a flexible substrate made of polycarbonate, polyethersulfone, polyethylene terephthalate, or the like can be used.

(Electrode) The electrodes 13 and 14 are made of ITO
A transparent conductive film represented by (Indium Tin Oxide), a metal electrode such as aluminum or silicon, or a photoconductive film such as amorphous silicon or BSO (Bismuth Silicon Oxide) can be used. In order to form the electrodes 13 and 14 in a strip shape, for example, an ITO film may be formed on the substrates 11 and 12 by a sputtering method or the like, and then patterned by a photolithography method.

(Insulating film, alignment control film, color filter)
The insulating thin film 15 is an inorganic film such as silicon oxide or an organic film such as a polyimide resin, an epoxy resin, an acrylic resin, or a urethane resin. The insulating thin film 15 prevents a short circuit between the electrodes 13 and 14, and serves as a gas barrier layer to improve the reliability of the liquid crystal. Has a function to improve. Alternatively, a polyimide resin or a silicon resin that functions as an alignment control film may be used. Further, if a pigment is added, it functions as a color filter. further,
The same material as the polymer used for the polymer structure 20 may be used as the insulating thin film 15.

(Spacer) Although not shown in FIG.
A spacer may be interposed between the substrates 11 and 12. As the spacer, for example, a sphere made of resin or inorganic oxide can be used, and the gap between the substrates 11 and 12 is kept uniform. Without providing the polymer structure 20, only the spherical spacer may be used as the space holding member.

(Liquid Crystal Composition) As the liquid crystal composition, the following two types can be used. In the first liquid crystal composition, a chiral material is added to a nematic liquid crystal mixture containing a liquid crystal tolan compound, a liquid crystal terphenyl compound, and a liquid crystal phenylcyclohexyl compound so as to exhibit a cholesteric phase at room temperature. In the second liquid crystal composition, a chiral material is added to a nematic liquid crystal mixture containing a liquid crystal ester compound, a liquid crystal terphenyl compound, and a liquid crystal phenylcyclohexyl compound so as to exhibit a cholesteric phase at room temperature. The selective reflection wavelength can be adjusted depending on the amount of the chiral material added, and the selective reflection wavelength can be set in the visible light range or outside the visible light range. An additive such as a dye may be added to the liquid crystal composition.

The liquid crystalline terphenyl compound is excellent in light stability and chemical stability, and expands the display temperature range. Further, the refractive index anisotropy is improved, the Y value at the time of coloring is improved, and as a result, the contrast is improved. F group, C
A liquid crystalline terphenyl compound containing at least one of an l group or a CN group is preferable in terms of improving the dielectric anisotropy and lowering the driving voltage. However, if the amount of the liquid crystalline terphenyl compound is too large, the viscosity increases, and the responsiveness tends to decrease. In addition, there is a problem that a smectic phase is likely to appear particularly at a low temperature.

The liquid crystalline tolan compound and the liquid crystalline phenylcyclohexyl compound have low viscosities and improve the response during driving. With the improvement of the response, the Y value at the time of coloring and at the time of transparency also improves, and the contrast improves. Further, by using a liquid crystalline phenylcyclohexyl compound having a large dielectric anisotropy, the driving voltage is reduced. However, if the amount of the liquid crystalline phenylcyclohexyl compound is too large, the compatibility with peripheral members such as a sealing material is high, so that the peripheral members are dissolved in the liquid crystal and display characteristics are deteriorated.

Therefore, a liquid crystalline tolan compound, a liquid crystalline terphenyl compound and a liquid crystalline phenylcyclohexyl compound are used in combination, and a chiral material is added to this nematic liquid crystal mixture so that the chiral nematic liquid crystal composition exhibits a cholesteric phase at room temperature. By preparing, it is possible to improve the responsiveness while keeping the drive voltage low.

As the liquid crystalline terphenyl compound, an F group,
Those containing a polar group such as a Cl group or a CN group may be used. By using the liquid crystalline terphenyl compound containing a polar group, the dielectric anisotropy of the liquid crystal composition is further improved, and the driving voltage can be further suppressed.

Further, the liquid crystalline ester compound has a high dielectric anisotropy and is therefore preferable in that the driving voltage is reduced. However, liquid crystal ester compounds generally have a high viscosity and a disadvantage that the response speed is slow. Further, the liquid crystal ester compound generally has a small refractive index anisotropy and cannot obtain a sufficient contrast.

Accordingly, a liquid crystalline terphenyl compound having a large refractive index anisotropy and a wide temperature compensation range and a liquid crystalline phenylcyclohexyl compound having a low viscosity and a high refractive index anisotropy are used in combination with the liquid crystalline ester compound. However, by adding a chiral material to this nematic liquid crystal mixture and preparing a chiral nematic liquid crystal composition so as to exhibit a cholesteric phase at room temperature, it is possible to improve the responsiveness while suppressing the driving voltage low.

As the liquid crystalline ester compound, F group, Cl
A group containing a polar group such as a group or a CN group may be used.
By using a liquid crystalline ester compound containing a polar group, the dielectric anisotropy of the liquid crystal composition is further improved, and the driving voltage can be further suppressed.

In the first liquid crystal composition, the content of the liquid crystalline tolan compound is about 1 to the nematic liquid crystal mixture.
It is preferable that the content be 0 wt% or more. The upper limit of the content is preferably about 40 wt%. The content of the liquid crystalline terphenyl compound is about 3 to the nematic liquid crystal mixture.
It is preferable that the content be 0 wt% or more. The upper limit of the content is preferably about 65 wt%, more preferably about 60 wt%. The content of the liquid crystalline phenylcyclohexyl compound is about 10 wt.
% Is preferable. The upper limit of the content is about 25w
It is preferably t%, more preferably about 20 wt%. Further, the total content of the liquid crystalline tolan compound, the liquid crystalline terphenyl compound and the liquid crystalline phenylcyclohexyl compound is about 50 wt% based on the nematic liquid crystal mixture.
It is preferable to make the above. The upper limit of the total content of the three types is not limited and may be 100 wt%, but may be, for example, about 70 wt%.

In the second liquid crystal composition, the content of the liquid crystal ester compound is preferably about 30 wt% or more based on the nematic liquid crystal mixture. The upper limit of the content is preferably about 60 wt%. The content of the liquid crystalline terphenyl compound is preferably about 10% by weight or more based on the nematic liquid crystal mixture. The upper limit of the content is preferably about 40 wt%. The content of the liquid crystalline phenylcyclohexyl compound is preferably about 10 wt% or more based on the nematic liquid crystal mixture. The upper limit of the content is preferably about 30 wt%. Further, the total content of the liquid crystal ester compound, the liquid crystal terphenyl compound and the liquid crystal phenylcyclohexyl compound is preferably about 50 wt% or more based on the liquid crystal mixture. The upper limit of the total content of the three types is not limited, and may be 100 wt%.
t%.

Here, preferred liquid crystalline tolan compounds, liquid crystalline terphenyl compounds, liquid crystalline phenylcyclohexyl compounds and liquid crystalline ester compounds of the general formula (A),
(B), (C), (D) and a specific chemical structural formula (A
1)-(A50), (B1)-(B83), (C1)-
(C17) and (D1) to (D84) are shown. The specific compounds are not limited to these.

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In addition to these, the liquid crystal composition may contain a liquid crystal component such as a polycyclic compound or an N-type (non-polar) compound for increasing the phase transition temperature to an isotropic phase. In addition, the first liquid crystal composition may include a small amount of a liquid crystalline ester compound, and the second liquid crystal composition may include a small amount of a liquid crystalline tolan compound.

The chiral nematic liquid crystal composition has an advantage that the pitch of the helical structure can be changed by changing the amount of the chiral material to be added, whereby the selective reflection wavelength of the liquid crystal can be controlled. In general, as a term representing the pitch of the helical structure of the liquid crystal molecules, “helical pitch” defined by the distance between the molecules when the liquid crystal molecules rotate 360 ° along the helical structure of the liquid crystal molecules is used. .

The chiral material is an additive having a function of twisting liquid crystal molecules when added to a nematic liquid crystal. By adding a chiral material to a nematic liquid crystal, a helical structure of liquid crystal molecules having a predetermined twist interval is generated, thereby exhibiting a cholesteric phase. The use of multiple types of chiral materials not only changes the phase transition temperature of the liquid crystal, reduces the change in the selective reflection wavelength according to the temperature change, but also provides dielectric anisotropy, refractive index anisotropy and viscosity. Can change various physical property values of the liquid crystal, and has a function of improving characteristics as a display element.

[0081] Two or more kinds of chiral materials may be contained. By adding a plurality of types of chiral materials, it is possible to prevent the selective reflection wavelength from shifting due to the ambient temperature. In the case of including a plurality of types of chiral materials, the liquid crystal may include two types of chiral materials having the same direction of twist, or include two types of chiral materials having opposite directions of twist. Is also good. The added amount is preferably 10 to 45 wt% (particularly 15 to 35 wt%) in total with respect to the whole liquid crystal composition. 45w
If it exceeds t%, problems such as an increase in driving voltage and precipitation of crystals will occur. The amount of chiral material added is 10wt
%, There is a possibility that the liquid crystal composition cannot be provided with a desired selective reflection wavelength.

The chiral material is, for example, a biphenyl compound, a terphenyl compound, an ester compound or the like having an optically active group at the terminal. The nematic liquid crystal has a layered helical structure (the liquid crystal molecules are formed along the helical structure of the liquid crystal molecules). Those which induce a 360 ° rotated molecular structure can be used. Cholesteric liquid crystals having a cholesterol ring represented by cholesteric nanoate can also be used.

As the dye to be added, a dye that absorbs at least light having a wavelength other than the selective reflection wavelength range of the liquid crystal composition or a dye that has a property of absorbing light having a wavelength of the selective reflection wavelength of the liquid crystal composition is used. It is desirable. As a specific material, various conventionally known dyes such as an azo compound, a quinone compound, an anthraquinone compound and the like or a dichroic dye can be used, and a plurality of these may be used. The added amount is desirably 3 wt% or less based on the total amount of the liquid crystal component and the chiral material.

When a color filter is employed in place of the addition of a dye, an additional filter layer material may be a colorless and transparent substance obtained by adding a dye. It may be a material that is inherently colored without adding a dye, or a thin film of a specific substance that functions similarly to the dye. It is clear that the same effect can be obtained by replacing the transparent substrate itself with the above filter layer material instead of disposing the filter layer.

(Polymer Structure) The polymer structure 20 may have any shape, such as a columnar body, an elliptical body, or a square pillar, and its arrangement may be random. And may have regularity such as a lattice shape. By providing such a polymer structure, it is easy to keep the gap between the substrates constant, and the self-holding property of the liquid crystal display element itself can be enhanced. In particular, when dot-shaped polymer structures are arranged at regular intervals, it is easy to make display performance uniform.

In order to form a polymer structure, a photo-curable resin material such as a photoresist material made of an ultraviolet-curable monomer is used to apply a desired thickness to a substrate, and this is irradiated with ultraviolet light through a mask. For example, a so-called photolithography method of performing pattern exposure and removing an uncured portion can be used.

A polymer structure made of a thermoplastic resin may be formed using a resin material in which a thermoplastic resin is dissolved in an appropriate solvent. In this case, a resin material is applied onto the substrate from the tip of the nozzle, such as a printing method for printing on the substrate by extruding a thermoplastic resin material with a squeegee using a screen plate or a metal mask, or a dispenser method or an inkjet method. The polymer structure can be disposed by a method of forming by discharging, or a transfer method of transferring a resin material onto a flat plate or a roller and then transferring the resin material to the substrate surface. After the opposing substrate is placed on the polymer structure arranged in this way, by heating and pressing, a liquid crystal cell in which the polymer structure is sandwiched between the substrates can be manufactured.

In order to form a liquid crystal display element, a liquid crystal composition may be injected between substrates holding a polymer structure by a vacuum injection method or the like. The liquid crystal composition may be dropped when the substrates are bonded, and the liquid crystal composition may be sealed at the same time as the substrates are bonded.

Further, in order to improve the accuracy of controlling the gap between the substrates, when forming the structure, a spacer material having a size smaller than the thickness of the resin, for example, glass fiber, ball-shaped glass or ceramic powder, or an organic material By disposing spherical particles made of such that the gap is hardly changed by heating or pressurizing, gap accuracy is further improved, and uneven voltage and uneven coloring can be reduced.

(Sealant) The sealant 22 is for enclosing the liquid crystal composition 21 so as not to leak out of the substrates 11 and 12, and is made of a thermosetting resin such as an epoxy resin or an acrylic resin, or a photocurable resin. An adhesive or the like can be used.

Experimental Example 1 The structural formulas (A1) and (A1)
6), (A34), (A35), and 22% by weight of the liquid crystalline tolan compound represented by (A37), and the structural formula (B1)
~ (B5), (B10), (B11), (B25),
58 wt% of a liquid crystalline terphenyl compound represented by any one of (B60) to (B64), and the structural formulas (C1), (C5),
Nematic liquid crystal containing 20 wt% of a liquid crystalline phenylcyclohexyl compound represented by (C10) (refractive index anisotropy Δ
n: 0.181, dielectric anisotropy Δε: 26.0, phase transition temperature T _NI to isotropic phase: 99.7 ° C., viscosity η: 56.5c
P), chiral materials CB15, R811, R1011
(Manufactured by Merck) at a ratio of 25:40:35 was added so as to be 22% by weight based on the total amount of the liquid crystal composition, to prepare a chiral nematic liquid crystal composition that selectively reflects light having a wavelength around 680 nm. did.

Next, a polyimide-based orientation control film AL4552 (manufactured by JSR Corporation) was formed to a thickness of 800 angstroms on the transparent electrode forming surface of the PES film on which the patterned transparent electrode was formed, and used as a first substrate. . Then, a predetermined amount of a gap controlling spacer having a diameter of 7 μm was sprayed on the orientation control film forming surface of the first substrate, and then a seal material XN21S (manufactured by Mitsui Chemicals, Inc.) was screen-printed on the periphery in a continuous mesh pattern. . At the same time, an insulating film HIM3000 (manufactured by Hitachi Chemical Co., Ltd.) is formed to a thickness of 2000 angstroms on another PES film (second substrate) on which the patterned transparent electrode is formed, and an orientation control film AL4552 is further formed thereon. Was formed to a thickness of 800 Å. No rubbing treatment was performed on the alignment control film in both substrates.

Subsequently, a resin material mainly composed of a thermoplastic resin is placed on a second substrate on a metal mask having a large number of holes having a diameter of about 100 μm formed at intervals of about 500 μm, and a squeegee is used. Screen printing, height about 7
The polymer structure was formed in a column shape of μm. And the first
The liquid crystal composition was applied on a substrate, the first and second substrates were bonded using a bonding apparatus, and heated at 150 ° C. for 1 hour. Further, a black light absorbing layer was provided on the back surface of the second substrate, and a red color filter having a thickness of 1000 Å was provided on the surface of the first substrate.

In such a liquid crystal display element, when a pulse voltage of 70 V was applied between the electrodes for 3 msec, the liquid crystal display element was colored red (planar state) and the Y value was 5.80. When a pulse voltage of 30 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 0.95, and the contrast was 6.11.
The reflectance in the planar state was 39.7.

The prepared chiral nematic liquid crystal composition was sealed in a brown vial (manufactured by Nichiden Rika Co., Ltd.) under an argon atmosphere and stored in a constant temperature bath at 70 ° C. for 3 days (high temperature storage treatment). When a liquid crystal display device was manufactured by the above procedure, performance equivalent to that of a liquid crystal display device manufactured using the chiral nematic liquid crystal composition not subjected to the high-temperature preservation treatment was exhibited.

The measurement of the Y value and the reflectance was performed using a spectrophotometer CM-3700d (manufactured by Minolta) having a white light source. The same applies to the following examples and comparative examples.

Experimental Example 2 The structural formulas (A1) and (A1)
5), 24 wt% of the liquid crystalline trans compound represented by (A35) to (A37), and the structural formulas (B1) to (B5),
(B11)-(B15), (B27), (B59)-
Liquid crystalline terphenyl compound 60w represented by (B65)
nematic liquid crystal containing 16% by weight of a liquid crystalline phenylcyclohexyl compound represented by the formula (C3) or (C7) (refractive index anisotropy Δn 0.178: dielectric anisotropy Δε: 24.4; Phase transition temperature T _NI to isotropic phase: 9
5.6 ° C., viscosity η: 53.2 cP) and chiral material CB
15, R811, R1011 (manufactured by Merck) at 25: 4
The mixture obtained at a ratio of 0:35 was 2 to the total amount of the liquid crystal composition.
2.1 wt%, and adjusted so as to selectively reflect light having a wavelength near 680 nm.
-426) was added to prepare a chiral nematic liquid crystal composition.

Next, a polyimide-based orientation control film AL4552 (manufactured by JSR Corporation) was formed to a thickness of 800 Å on the transparent electrode forming surface of the PC film on which the patterned transparent electrode was formed, and used as a first substrate. . After a predetermined amount of a gap control spacer having a diameter of 7 μm was sprayed on the orientation control film forming surface of the first substrate, a sealing material XN21S (manufactured by Mitsui Chemicals, Inc.) was screen-printed on the periphery in a continuous mesh shape. . At the same time, an insulating film HIM3000 (manufactured by Hitachi Chemical Co., Ltd.) is formed to a thickness of 2000 angstroms on another PES film (second substrate) on which a patterned transparent electrode is formed, and an orientation control film AL4552 is further formed thereon. Was formed to a thickness of 800 Å. No rubbing treatment was performed on the alignment control film in both substrates.

Subsequently, a resin material mainly composed of a thermoplastic resin is placed on a second substrate on a metal mask in which a large number of holes having a diameter of about 100 μm are formed at intervals of about 500 μm, and a squeegee is used. Screen printing, height about 7
The polymer structure was formed in a column shape of μm. And the first
The liquid crystal composition was applied on a substrate, the first and second substrates were bonded using a bonding apparatus, and heated at 150 ° C. for 1 hour. Further, a black light absorbing layer was provided on the back surface of the second substrate.

In such a liquid crystal display element, when a pulse voltage of 65 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 5.65. When a pulse voltage of 35 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 1.11, and the contrast was 5.09.
The reflectance in the planar state was 38.1.

A chiral nematic liquid crystal composition which had been subjected to a high-temperature storage treatment in the same manner as in Experimental Example 1 was used to produce a liquid crystal display device in the same procedure as described above. Performance equivalent to that of the liquid crystal display device.

Experimental Example 3 The structural formulas (D9) to (D1)
5), 58 wt% of the liquid crystalline ester compounds represented by (A65) to (D67) and the structural formulas (B1) and (B4)
To (B6) and (B60), and 15 wt% of the liquid crystalline phenylcyclohexyl compound represented by the structural formulas (C1) and (C5).
% Nematic liquid crystal (refractive index anisotropy Δn: 0.17
5, dielectric anisotropy Δε: 20.5, phase transition temperature to isotropic phase T _NI : 100.2 ° C., viscosity η: 51.5 cP), and a chiral material CB15, R811, R1011 (manufactured by Merck) Was added at 27:43:30 so as to be 22 wt% with respect to the total amount of the liquid crystal composition, and 680 n
A chiral nematic liquid crystal composition was prepared so that light having a wavelength around m was selectively reflected, and further, 0.8 wt% of a dye (SI-426) was added.

Next, a polyimide-based orientation control film AL4552 (manufactured by JSR Corporation) was formed to a thickness of 800 Å on the transparent electrode forming surface of the glass substrate on which the patterned transparent electrode was formed, and used as a first substrate. . Then, after a predetermined amount of a gap control spacer having a diameter of 7 μm was sprayed on the orientation control film forming surface of the first substrate, a seal material XN21S was screen-printed on the periphery in a continuous mesh shape. At the same time, an insulating film HIM3000 was formed to a thickness of 2000 angstroms on a glass substrate (second substrate) on which a patterned transparent electrode was formed, and an orientation control film AL4552 was formed thereon to a thickness of 800 angstroms. No rubbing treatment was performed on the alignment control film in both substrates.

Next, a predetermined amount of an acrylate monomer R684 containing 5 wt% of a photopolymerization initiator was dropped on the first glass substrate, and a photomask having openings of 50 μm ² formed thereon at intervals of 50 μm was placed thereon. Ultraviolet rays were irradiated while pressing with a constant load. Thereafter, when the photomask was peeled off and the uncured portion was washed with ethanol, columnar structures having a height of 7 μm and a height of 50 μm ² were formed at predetermined intervals in a predetermined area. Subsequently, the first and second substrates were heated while being pressed, and the sealing material was cured to form a cell, and the liquid crystal composition was injected into the cell. A light absorbing layer was provided, but no red color filter was provided.

In such a liquid crystal display element, when a 65 V pulse voltage was applied between the electrodes for 3 msec, the liquid crystal display element was colored red (planar state) and the Y value was 5.50. When a pulse voltage of 40 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 0.98, and the contrast was 5.61.
The reflectance in the planar state was 37.5. Good display characteristics were obtained even in a cell having a columnar structure formed by the photolithography method.

A liquid crystal display device was prepared in the same procedure as described above by using the chiral nematic liquid crystal composition which had been subjected to high-temperature storage treatment in the same manner as in Experimental Example 1, and a liquid crystal composition which had not been subjected to high-temperature storage treatment was used. Performance equivalent to that of the liquid crystal display device.

Experimental Example 4 The structural formulas (D1) to (D1)
0), (D45), (D48), (D65) to (D6)
8), the liquid crystalline terphenyl compound represented by the structural formulas (B3), (B6) to (B9) 20 wt%, and the structural formula (C)
1), 20 wt% of a liquid crystalline phenylcyclohexyl compound represented by (C10) or (C11);
Nematic liquid crystal containing 5 wt% of the liquid crystalline tolan compound represented by 1) (refractive anisotropy Δn: 0.181, dielectric anisotropy Δε: 25.1, phase transition temperature to isotropic phase T _NI : 9)
9.8 ° C., viscosity η: 49.3) and chiral material CB1
5, R811, R1011 (Merck) 25: 4
A mixture of 0:35 was added to the total amount of the liquid crystal composition by 2%.
0 wt% was added to prepare a chiral nematic liquid crystal composition that selectively reflects light having a wavelength of around 680 nm.

Next, a cell made of the same structure and material as in Experimental Example 1 was manufactured by the same method, and the liquid crystal composition was sealed.
Experimental Example 1 also provided a light absorbing layer and a red color filter.
Is the same as

In such a liquid crystal display device, when a pulse voltage of 70 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 5.09. When a pulse voltage of 35 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 1.15, and the contrast was 4.42.
The reflectance in the planar state was 39.1.

A liquid crystal display device was prepared in the same procedure as described above using a chiral nematic liquid crystal composition which had been subjected to high-temperature storage treatment in the same manner as in Experimental Example 1, and a liquid crystal composition which had not been subjected to high-temperature storage treatment was used. Performance equivalent to that of the liquid crystal display device.

Experimental Example 5 The structural formulas (A1) and (A1)
6), 22 wt% of the liquid crystalline trans compound represented by (A34) to (A37), and the structural formulas (B1) to (B5),
(B10)-(B12), (B25), (B60)-
Liquid crystalline terphenyl compound 58w represented by (B63)
t% and 20 wt% of a liquid crystalline phenylcyclohexyl compound represented by the structural formulas (C1) to (C3) and (C8).
Liquid crystal containing (anisotropy of refractive index Δn: 0.18)
5, dielectric anisotropy Δε: 23.2, phase transition temperature to isotropic phase T _NI : 95.8 ° C, viscosity η: 60.6 cP), and chiral materials CB15, R811, R1011 (manufactured by Merck)
Was added at a ratio of 25:40:35 so as to be 29.0 wt% with respect to the total amount of the liquid crystal composition, and 560 n
m is adjusted so as to selectively reflect light having a wavelength near m, and the dye (Kayaset Yellow GN) is adjusted to 0.6.
A chiral nematic liquid crystal composition to which wt% was added was prepared.

Next, a cell made of the same structure and material as in Experimental Example 1 was manufactured by the same method, and the liquid crystal composition was sealed.
The light absorbing layer was provided but the green color filter was not provided.

In such a liquid crystal display device, when a pulse voltage of 80 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 24.85. When a pulse voltage of 40 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 1.65, and the contrast was 15.06. The reflectance in the planar state was 41.5.

A chiral nematic liquid crystal composition which had been subjected to high-temperature storage treatment in the same manner as in Experimental Example 1 was used to produce a liquid crystal display device in the same procedure as described above. Performance equivalent to that of the liquid crystal display device.

Experimental Example 6 The structural formulas (A1) and (A1)
5), 24 wt% of the liquid crystalline trans compound represented by (A35) to (A37), and the structural formulas (B1) to (B5),
(B11)-(B15), (B27), (B59)-
Liquid crystalline terphenyl compound 60w represented by (B65)
nematic liquid crystal containing 16% by weight of a liquid crystalline phenylcyclohexyl compound represented by the above structural formulas (C3) and (C7) (refractive index anisotropy Δn: 0.183, dielectric anisotropy Δε: 19.3) , Isotropic phase transition temperature T _NI : 9
3.5 ° C, viscosity η: 62.3 cP) and chiral material CB
15, R811, R1011 (manufactured by Merck) at 25: 4
A mixture of 0:35 was added to the total amount of the liquid crystal composition by 2%.
8.5 wt%, and adjusted so as to selectively reflect light having a wavelength of around 560 nm.
A chiral nematic liquid crystal composition to which 0.6% by weight of YET Yellow GN was added was prepared.

Next, a cell made of the same structure and material as in Experimental Example 2 was manufactured by the same method, and the liquid crystal composition was sealed.
The light absorbing layer was provided but the green color filter was not provided.

In such a liquid crystal display element, when a pulse voltage of 80 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 24.30. When a pulse voltage of 40 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 1.50, and the contrast was 16.20. The reflectance in the planar state was 42.0.

A chiral nematic liquid crystal composition which had been subjected to high-temperature preservation treatment in the same manner as in Experimental Example 1 was used to produce a liquid crystal display device in the same procedure as described above. Performance equivalent to that of the liquid crystal display device.

Experimental Example 7 The structural formulas (D9) to (D1)
5), (D50) to (D53), (D60), (D6)
5) a liquid crystalline ester compound represented by the formula (B1) to (B6), (B30), (B32):
A nematic liquid crystal (refractive anisotropy Δn: 0.165, dielectric constant) containing 15 wt% of a liquid crystalline terphenyl compound represented by the following formula and 26 wt% of a liquid crystalline phenylcyclohexyl compound represented by the structural formulas (C1) and (C9) Anisotropy Δε:
21.9, a phase transition temperature T _NI to an isotropic phase: 94.5 ° C., a viscosity η: 62.0 cP), and a chiral material CB15, R81.
A mixture of 1, R1011 (manufactured by Merck) at 27:43:30 was 30.0 wt% based on the total amount of the liquid crystal composition.
To prepare a chiral nematic liquid crystal composition that selectively reflects light having a wavelength around 560 nm.

Next, a cell made of the same structure and material as in Experimental Example 1 was manufactured by the same method, and the liquid crystal composition was sealed.
Experimental Example 1 also provided a light absorbing layer and a green color filter.
Is the same as

In such a liquid crystal display element, when a pulse voltage of 75 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 23.80. When a pulse voltage of 45 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 1.55, and the contrast was 15.35. The reflectance in the planar state was 43.5.

A liquid crystal display device was prepared in the same procedure as described above using a chiral nematic liquid crystal composition that had been subjected to high-temperature storage treatment in the same manner as in Experimental Example 1, and a liquid crystal composition that had not been subjected to high-temperature storage treatment was used. Performance equivalent to that of the liquid crystal display device.

Experimental Example 8 The structural formulas (D1) to (D1)
0), (D45), (D48), (D65) to (D6)
8), 20 wt% of the liquid crystalline terphenyl compounds represented by the structural formulas (B3) and (B6) to (B8), and 55 wt% of the liquid crystalline ester compound represented by the structural formula (C).
1) A nematic liquid crystal containing 25 wt% of a liquid crystalline phenylcyclohexyl compound represented by (C10), (C11), or (C13) (refractive index anisotropy Δn: 0.187, dielectric anisotropy Δε: 24.8) , Isotropic phase transition temperature T _NI :
95.0 ° C., viscosity η: 59.3 cP) and chiral material C
B15, R811, R1011 (manufactured by Merck) at 27:
The mixture obtained at 43:30 was added so as to be 30.0 wt% with respect to the total amount of the liquid crystal composition, and adjusted so as to selectively reflect light having a wavelength of around 560 nm.
A chiral nematic liquid crystal composition to which 0.6% by weight of C.Ayset Yellow GN) was added was prepared.

Next, a cell made of the same structure and material as in Experimental Example 3 was manufactured by the same method, and the liquid crystal composition was sealed.
The light absorbing layer was provided but the green color filter was not provided.

In such a liquid crystal display element, when a pulse voltage of 75 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 25.30. When a pulse voltage of 40 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 1.43, and the contrast was 17.69. The reflectance in the planar state was 42.0.

A liquid crystal display device was prepared in the same procedure as described above using a chiral nematic liquid crystal composition which had been subjected to high-temperature storage treatment in the same manner as in Experimental Example 1, and a liquid crystal composition which had not been subjected to high-temperature storage treatment was used. Performance equivalent to that of the liquid crystal display device.

Experimental Example 9 The structural formulas (A1) and (A1)
6), (A34), (A35), and 22% by weight of the liquid crystalline tolan compound represented by (A37), and the structural formula (B1)
~ (B5), (B10), (B11), (B25),
58 wt% of a liquid crystalline terphenyl compound represented by any one of (B60) to (B64), and the structural formulas (C1), (C5),
Nematic liquid crystal containing 20 wt% of a liquid crystalline phenylcyclohexyl compound represented by (C10) (refractive index anisotropy Δ
n: 0.183, dielectric anisotropy Δε: 21.8, phase transition temperature T _NI to isotropic phase: 90.3 ° C., viscosity η: 69.0 c
P), chiral materials CB15, R811, R1011
(Merck) was added at a ratio of 25:40:35 so as to be 32 wt% with respect to the total amount of the liquid crystal composition to prepare a chiral nematic liquid crystal composition that selectively reflects light having a wavelength around 490 nm. did.

Next, a cell made of the same structure and material as in Experimental Example 1 was manufactured by the same method, and the liquid crystal composition was sealed.
A light absorbing layer was provided, but no color filter was provided.

In such a liquid crystal display device, when a pulse voltage of 70 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 10.93. When a pulse voltage of 40 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 0.97, and the contrast was 11.27. The reflectance in the planar state was 40.5.

A liquid crystal display device was prepared in the same procedure as described above using a chiral nematic liquid crystal composition which had been subjected to high-temperature storage treatment in the same manner as in Experimental Example 1, and a liquid crystal composition which had not been subjected to high-temperature storage treatment was used. Performance equivalent to that of the liquid crystal display device.

Experimental Example 10 The structural formulas (A1) and (A1)
5), 24 wt% of the liquid crystalline trans compound represented by (A35) to (A37), and the structural formulas (B1) to (B5),
(B11)-(B15), (B27), (B59)-
Liquid crystalline terphenyl compound 60w represented by (B65)
nematic liquid crystal containing 16% by weight of a liquid crystalline phenylcyclohexyl compound represented by the above structural formulas (C3) and (C7) (refractive index anisotropy Δn: 0.167, dielectric anisotropy Δε: 18.2) , Isotropic phase transition temperature T _NI : 8
9.2 ° C., viscosity η: 72.3 cP) and chiral material CB
15, R811, R1011 (manufactured by Merck) at 25: 4
The mixture at 0:35 was mixed with the total amount of the liquid crystal composition by 3
1.8 wt% was added to prepare a chiral nematic liquid crystal composition that selectively reflects light having a wavelength of around 490 nm.

Next, a cell made of the same structure and material as in Experimental Example 2 was manufactured by the same method, and the liquid crystal composition was sealed.
A light absorbing layer was provided, but no color filter was provided.

In such a liquid crystal display element, when a pulse voltage of 65 V was applied between the electrodes for 3 msec, the liquid crystal display element was colored red (planar state) and the Y value was 9.99. When a pulse voltage of 30 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 0.90, and the contrast was 11.10. The reflectance in the planar state was 41.3.

A liquid crystal display device was prepared in the same procedure as described above by using the chiral nematic liquid crystal composition which had been subjected to high-temperature storage treatment in the same manner as in Experimental Example 1, and the liquid crystal composition which had not been subjected to high-temperature storage treatment was used. Performance equivalent to that of the liquid crystal display device.

Experimental Example 11 The structural formulas (D1) to (D1)
10), (D45), (D48), (D65) to (D6)
8), the liquid crystalline terphenyl compound represented by the structural formulas (B3), (B6) to (B9) 20 wt%, and the structural formula (C)
1) Nematic liquid crystals containing 15 wt% of a liquid crystalline phenylcyclohexyl compound represented by (C10) and (C11) (refractive index anisotropy Δn: 0.168, dielectric anisotropy Δ
ε: 25.6, phase transition temperature to isotropic phase T _NI : 92.0
° C, viscosity η: 69.5 cP), chiral material CB15,
R811, R1011 (manufactured by Merck) at 25: 40: 3
5 was added to the total amount of the liquid crystal composition by 32.5.
wt% so as to prepare a chiral nematic liquid crystal composition that selectively reflects light having a wavelength around 490 nm.

Next, a cell made of the same structure and material as in Experimental Example 1 was manufactured by the same method, and the liquid crystal composition was sealed.
A light absorbing layer was provided, but no color filter was provided.

In such a liquid crystal display element, when a 65 V pulse voltage was applied between the electrodes for 3 msec, the liquid crystal display element was colored red (planar state) and the Y value was 10.50. When a pulse voltage of 35 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 0.95, and the contrast was 11.05. The reflectance in the planar state was 40.7.

A liquid crystal display device was prepared in the same procedure as described above using the chiral nematic liquid crystal composition which had been subjected to a high-temperature storage treatment in the same manner as in Experimental Example 1, and a liquid crystal composition which had not been subjected to the high-temperature storage treatment was used. Performance equivalent to that of the liquid crystal display device.

Experimental Example 12 The structural formulas (D9) to (D9)
15), (D50) to (D53), (D60), (D6)
5) a liquid crystalline ester compound represented by the formula (B1) to (B6), (B30), (B32):
Nematic liquid crystal containing 15 wt% of a liquid crystalline terphenyl compound represented by the formula and 26 wt% of a liquid crystalline phenylcyclohexyl compound represented by the structural formulas (C1) and (C9) (refractive anisotropy Δn: 0.187, dielectric constant) Anisotropy Δε:
22.9, phase transition temperature T _NI to isotropic phase: 87.7 ° C., viscosity η: 70.3 cP), and chiral materials CB15, R81
A mixture of 1, R1011 (manufactured by Merck) at 27:43:30 was 32.0 wt% based on the total amount of the liquid crystal composition.
To prepare a chiral nematic liquid crystal composition that selectively reflects light having a wavelength around 490 nm.

Next, a cell made of the same structure and material as in Experimental Example 2 was manufactured by the same method, and the liquid crystal composition was sealed.
A light absorbing layer was provided, but no color filter was provided.

In such a liquid crystal display element, when a pulse voltage of 60 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 9.98. When a pulse voltage of 30 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 0.89, and the contrast was 11.21.
The reflectance in the planar state was 40.7.

A chiral nematic liquid crystal composition was subjected to a high-temperature preservation treatment in the same manner as in Experimental Example 1 to produce a liquid crystal display device in the same procedure as described above, and a liquid crystal composition not subjected to the high-temperature preservation treatment was used. Performance equivalent to that of the liquid crystal display device.

Comparative Example 1 The structural formulas (A6) and (A6)
Nematic containing 35% by weight of a liquid crystalline tolan compound represented by the formula (9) and 25% by weight of a liquid crystalline phenylcyclohexyl compound represented by the structural formulas (C3) and (C4) and excluding a liquid crystalline terphenyl compound and a liquid crystalline ester compound. Liquid crystal (Δn: 0.130, Δε: 10.2, T _NI :
85.0 ° C., viscosity η: 58.0 cP), and a mixture of chiral material CB15 and R1011 (manufactured by Merck) at 73:27, 28.5 wt% based on the total amount of the liquid crystal composition.
And a chiral nematic liquid crystal composition that selectively reflects light having a wavelength around 680 nm was prepared.

Next, a cell made of the same structure and material as in Experimental Example 1 was manufactured by the same method, and the liquid crystal composition was sealed.
Experimental Example 1 also provided a light absorbing layer and a red color filter.
Is the same as

In such a liquid crystal display element, when a pulse voltage of 100 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 4.48. When a pulse voltage of 50 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 1.45, and the contrast was 3.09.
The reflectance in the planar state was 30%.

A chiral nematic liquid crystal composition was subjected to a high-temperature preservation treatment in the same manner as in Experimental Example 1 to produce a liquid crystal display device in the same procedure as described above, and was evaluated in the same manner. The value was 3.50, the Y value was 2.52 in the focal conic state, and the contrast was 1.3.
9. The reflectance in the planar state was 15%, and all the characteristics were lower than those of the liquid crystal display device using the liquid crystal composition that had not been subjected to the high-temperature storage treatment.

Comparative Example 2 The structural formulas (B2) and (B2)
4) 50 wt% of a liquid crystalline terphenyl compound represented by (B12) and 33 wt% of a liquid crystalline cyanobiphenyl compound
% Nematic liquid crystal containing no liquid crystalline tolan compound and liquid crystalline phenylcyclohexyl compound (Δn:
0.135, Δε: 17.0, T _NI : 88.0 ° C., viscosity η: 63.0 cP), and a chiral material CB15, R101
1 (manufactured by Merck) at a ratio of 73:27 was added so as to be 29.0 wt% with respect to the total amount of the liquid crystal composition, and a chiral nematic liquid crystal composition that selectively reflected light having a wavelength around 680 nm was obtained. Prepared.

Next, a cell made of the same structure and material as in Experimental Example 1 was manufactured by the same method, and the liquid crystal composition was sealed.
Experimental Example 1 also provided a light absorbing layer and a red color filter.
Is the same as

In such a liquid crystal display element, when a pulse voltage of 100 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 5.69. When a pulse voltage of 50 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 1.92, and the contrast was 2.96.
The reflectance in the planar state was 30%.

A chiral nematic liquid crystal composition was subjected to a high-temperature preservation treatment in the same manner as in Experimental Example 1 to produce a liquid crystal display device in the same procedure as described above, and was evaluated in the same manner. The value is 4.57, the Y value is 3.30 in the focal conic state, and the contrast is 1.3.
8. The reflectance in the planar state was 15%, and all the characteristics were lower than those of the liquid crystal display device using the liquid crystal composition which had not been subjected to the high-temperature storage treatment.

Comparative Example 3 The structural formulas (A2) and (A
35 wt% of a liquid crystalline terphenyl compound represented by 4)
And a liquid crystal ester compound represented by the structural formulas (D2) and (D6) of 25 wt% and a liquid crystal cyanobiphenyl compound of 33 wt%, and excluding a liquid crystal tolan compound and a liquid crystal phenylcyclohexyl compound. : 0.147, Δε: 16.0, T _NI : 84.
5 ° C., viscosity η: 70.4 cP) and chiral material CB1
5, a mixture of R1011 (manufactured by Merck) at a ratio of 73:27 is added so as to be 32.5 wt% with respect to the total amount of the liquid crystal composition, and a chiral nematic liquid crystal composition that selectively reflects light having a wavelength around 490 nm. Was prepared.

Next, a cell made of the same structure and material as in Experimental Example 2 was manufactured by the same method, and the liquid crystal composition was sealed.
The light absorbing layer was provided, but no blue color filter was provided.

In such a liquid crystal display element, when a pulse voltage of 100 V was applied between the electrodes for 3 msec, it was colored red (planar state) and the Y value was 6.00. When a pulse voltage of 50 V was applied for 3 msec, the liquid crystal became transparent (focal conic state), the Y value was 2.01, and the contrast was 3.00.
The reflectance in the planar state was 35%.

A liquid crystal display device was manufactured in the same procedure as described above using a chiral nematic liquid crystal composition that had been subjected to a high-temperature preservation treatment in the same manner as in Experimental Example 1, and was evaluated in the same manner. The value is 4.90, the Y value is 3.50 in the focal conic state, and the contrast is 1.4.
0, the reflectance in the planar state was 20%, and all the characteristics were lower than those of the liquid crystal display device using the liquid crystal composition which had not been subjected to the high-temperature storage treatment.

(Other Embodiments) The liquid crystal composition and the liquid crystal light modulation device according to the present invention are not limited to the above embodiments and examples, but can be variously modified within the scope of the invention. is there.

In particular, the structure of the cell may be a network type in which a network-like composite film composed of a liquid crystal composition and a polymer resin composition is formed. Further, the columnar polymer structure may be short at the intermediate portion between the substrates.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a liquid crystal display device according to the present invention.

FIG. 2 is a sectional view showing a second embodiment of the liquid crystal display device according to the present invention.

FIG. 3 is a sectional view showing a third embodiment of the liquid crystal display device according to the present invention.

FIG. 4 is a sectional view showing a fourth embodiment of the liquid crystal display device according to the present invention.

FIG. 5 is a sectional view showing a fifth embodiment of the liquid crystal display device according to the present invention.

FIG. 6 is a sectional view showing a sixth embodiment of the liquid crystal display device according to the present invention.

FIG. 7 is a sectional view showing a seventh embodiment of the liquid crystal display device according to the present invention.

FIG. 8 is a sectional view showing an eighth embodiment of the liquid crystal display device according to the present invention.

FIG. 9 is a sectional view showing a ninth embodiment of the liquid crystal display device according to the present invention.

FIG. 10 is a sectional view showing a tenth embodiment of the liquid crystal display device according to the present invention.

[Explanation of symbols]

 11, 12 ... substrate 13, 14 ... electrode 15 ... insulating thin film 16, 17 ... alignment control film 18 ... color filter 20 ... columnar polymer structure 21 ... liquid crystal composition

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09K 19/54 C09K 19/54 B G02F 1/13 500 G02F 1/13 500 1/139 1/139 (72 ) Inventor Hideaki Ueda 2-313 Azuchicho, Chuo-ku, Osaka-shi, Osaka F-term in Osaka International Building Minolta Co., Ltd. (reference) 2H088 HA01 HA03 JA14 MA02 MA10 4H027 BA02 BD03 BD04 BD07 BD08 BD09 BD20 BD23 BE05 CB01 CC01 CC03 CC04 CE01 CG01 CG04 CM01 CM04 CP04 CS01 CS03 CU04 CW01

Claims (21)

[Claims] 1. A nematic liquid crystal mixture containing at least a liquid crystalline tolan compound, a liquid crystalline terphenyl compound and a liquid crystalline phenylcyclohexyl compound as main components, and at least one chiral material in an amount of 10 to 45 wt%, and cholesteric at room temperature. A liquid crystal composition exhibiting a phase. 2. A liquid crystal composition comprising a nematic liquid crystal mixture and a chiral material and exhibiting a cholesteric phase at room temperature is sandwiched between a pair of substrates at least one of which is transparent;
The nematic liquid crystal mixture mainly comprises a liquid crystalline tolan compound, a liquid crystalline terphenyl compound and a liquid crystalline phenylcyclohexyl compound, and the liquid crystal composition further comprises at least one chiral material in an amount of 10 to 45 wt%. Liquid crystal light modulator. 3. The total content of the liquid crystalline tolan compound, the liquid crystalline terphenyl compound and the liquid crystalline phenylcyclohexyl compound is 50 wt% based on the nematic liquid crystal mixture.
3. The liquid crystal composition or liquid crystal light modulation device according to claim 1, wherein 4. A liquid crystal composition or a liquid crystal light modulation device according to claim 1, wherein the content of the liquid crystalline tolan compound is 10 wt% or more based on the nematic liquid crystal mixture. 5. The liquid crystal composition or liquid crystal light modulation device according to claim 1, wherein the content of the liquid crystalline terphenyl compound is at least 30 wt% based on the nematic liquid crystal mixture. 6. The content of the liquid crystalline phenylcyclohexyl compound is 10 wt% based on the nematic liquid crystal mixture.
The liquid crystal composition or the liquid crystal light modulation device according to claim 1 or 2, wherein: 7. The liquid crystalline terphenyl compound is
The liquid crystal composition or the liquid crystal light modulation device according to claim 1, wherein the liquid crystal composition or the liquid crystal light modulation device includes at least one of a group, a Cl group, and a CN group. 8. The liquid crystal composition or the liquid crystal light modulation device according to claim 1, wherein the liquid crystal composition contains a plurality of types of chiral materials. 9. A nematic liquid crystal mixture containing at least a liquid crystal ester compound, a liquid crystal terphenyl compound and a liquid crystal phenylcyclohexyl compound as main components, and at least one chiral material in an amount of 10 to 45 wt%, and cholesteric at room temperature. A liquid crystal composition exhibiting a phase. 10. A liquid crystal composition comprising a nematic liquid crystal mixture and a chiral material and exhibiting a cholesteric phase at room temperature is sandwiched between at least one pair of transparent substrates,
The nematic liquid crystal mixture contains a liquid crystal ester compound, a liquid crystal terphenyl compound and a liquid crystal phenylcyclohexyl compound as main components, and the liquid crystal composition further contains 10 to 45 wt% of at least one kind of chiral material. Liquid crystal light modulator. 11. The total content of the liquid crystalline ester compound, the liquid crystalline terphenyl compound and the liquid crystalline phenylcyclohexyl compound is 50 to the nematic liquid crystal mixture.
The liquid crystal composition or the liquid crystal light modulation device according to claim 9 or 10, wherein the content is not less than wt%. 12. The liquid crystal composition or liquid crystal light modulation device according to claim 9, wherein the content of the liquid crystal ester compound is 30% by weight or more based on the nematic liquid crystal mixture. 13. The liquid crystal composition or the liquid crystal light modulation device according to claim 9, wherein the content of the liquid crystalline terphenyl compound is at least 10 wt% based on the nematic liquid crystal mixture. 14. The content of the liquid crystalline phenylcyclohexyl compound is 10 wt% based on the nematic liquid crystal mixture.
% Or more.
A liquid crystal composition or a liquid crystal light modulation device according to any one of the preceding claims. 15. The liquid crystalline ester compound according to claim 15, wherein
The liquid crystal composition or the liquid crystal light modulation device according to claim 9, wherein at least one of a Cl group and a CN group is contained. 16. The liquid crystal composition according to claim 9, wherein the liquid crystal composition contains a plurality of types of chiral materials.
A liquid crystal composition or a liquid crystal light modulation device according to any one of the preceding claims. 17. The liquid crystal composition or the liquid crystal light modulation device according to claim 1, wherein a dye is contained in the liquid crystal composition. 18. The liquid crystal light modulation device according to claim 2, wherein at least one of the pair of substrates is made of a resin. 19. The liquid crystal light modulation device according to claim 2, wherein an organic film is provided on an electrode formed on at least one of the pair of substrates. 20. The organic film according to claim 2, wherein the organic film has a function of an alignment control film and / or a color filter.
A liquid crystal light modulation device according to claim 10. 21. The liquid crystal light modulation device according to claim 2, wherein a plurality of polymer structures are provided between the pair of substrates.