JPH07138568A - Liquid crystal composition - Google Patents

Abstract

PURPOSE:To obtain the composition having good light resistance and a driving voltage low enough for satisfactory drive of an active element by using a specified compound for a liquid crystal composition used in a liquid display element composed of a polymer and a liquid crystal which are dispersed in or mixed with each other. CONSTITUTION:The composition is used in a display element composed of a polymer and a liquid crystal which are dispersed in or mixed with each other, and comprises 5-50wt.% of at least one member selected from the group consisting of a compound of formula I (wherein R is alkyl or alkoxyl), II, III, IV and V, or comprises, in addition to these compounds, 5-90wt.% of at least one member selected from the group consisting of a compound of formula VI, VII and VIII (wherein R<1> is F or H; and R<2> is F or alkyl). By selecting Rs of the compounds, a liquid crystal temperature range is the most suitable for the use can be attained. A dichroic coloring matter can be desirably used as the coloring matter.

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 used for a display device in which a polymer and a liquid crystal are dispersed or oriented and dispersed, which is applied to a display device such as an information equipment terminal, a television or an advertising board.

[0002]

2. Description of the Related Art In recent years, information devices have become smaller and more portable, and power consumption of display devices mounted on them has also been required. Therefore, recently, a bright reflective display device that does not use a polarizing plate is being developed. For example, a material which is transparent when an electric field is applied and which scatters when an electric field is not applied (Japanese Patent Publication No. 58-501631) or a material which scatters when an electric field is applied and absorbs light or becomes transparent when an electric field is not applied (Japanese Patent Application Laid-Open Nos. 4-227684 and 5-119302).
Etc.) are being developed. In addition, in order to enable the combination with the active element that is indispensable for large capacity display,
A liquid crystal composition that can be driven at a low voltage has been developed.
6 has been presented).

[0003]

However, in a polymer dispersed liquid crystal display device using such a liquid crystal composition, it is possible to polymerize the polymer precursor in the liquid crystal by using strong ultraviolet rays during the manufacturing process. Therefore, there is a problem in that the liquid crystal is damaged by ultraviolet rays, the specific resistance is lowered, and the liquid crystal cannot be driven by the active element. Also, even if you do not use ultraviolet rays in the manufacturing process, just store it in a place exposed to light after manufacturing,
There is a problem that the liquid crystal is decomposed by the irradiated light and the specific resistance is lowered, so that the active element cannot be driven. In particular, a cyanophenyl ester-based liquid crystal that can reduce the driving voltage and a liquid crystal having a benzene ring-substituted skeleton (pyridine, pyrimidine skeleton, etc.) have a problem of poor light resistance. When the liquid crystal deteriorates in this way, the charge retention rate when combined with an active element decreases, it becomes impossible to drive with the active element, and it becomes impossible to display a large capacity, which limits its use as a display. Become.

Therefore, the present invention is intended to solve such a problem, and an object of the present invention is to provide a liquid crystal composition having a good light resistance and a low driving voltage which can be sufficiently driven by an active element. It is in.

[0005]

The liquid crystal composition of the present invention comprises:
Regarding the liquid crystal composition used in the display device in which the polymer and the liquid crystal are dispersed or aligned and dispersed, Compound Group I

[0006]

[Chemical 9]

(R is an alkyl group or an alkoxy group) Compound group II

[0008]

[Chemical 10]

(R is an alkyl group or an alkoxy group) Compound group III

[0010]

[Chemical 11]

(R is an alkyl group or an alkoxy group) Compound group IV

[0012]

[Chemical 12]

(R is an alkyl group or an alkoxy group) Compound group V

[0014]

[Chemical 13]

At least one compound is selected from the group of compounds represented by the formula (R is an alkyl group or an alkoxy group),
The composition ratio of these compound groups is characterized by being 5% by weight to 50% by weight.

Further, in the above liquid crystal composition, compound group VI

[0017]

[Chemical 14]

(R is an alkyl group or an alkoxy group) Compound group VII

[0019]

[Chemical 15]

(R is an alkyl group or an alkoxy group) Compound group VIII

[0021]

[Chemical 16]

(R is an alkyl group or an alkoxy group, R is
1 is 5 or 90% of at least one compound group selected from the group of compounds represented by fluorine or hydrogen, and R2 is fluorine or an alkyl group).

The liquid crystal composition is also characterized by containing a dichroic dye. Details will be shown below in Examples.

[0024]

EXAMPLES Example 1 In this example, an example in which the compound group I, the compound group V, and the compound group VI shown above are mixed and used is shown. The composition of the liquid crystal used in this example is shown.

[0025]

[Table 1]

Using this liquid crystal composition, display devices were produced by the following various methods and Examples 2 to 9.

The R of each compound group is not limited to those shown here, but may be determined so as to have an optimum liquid crystal temperature range depending on the application. The mixing ratio of each compound group is not limited to the values shown here, and can be determined in consideration of the type and length of R, the operating temperature range required for the application, and the electro-optical characteristics.

The compound group VI used here has various variations depending on the substitution position of fluorine,
Here, only one part is shown. For example, fluorine may be substituted for all phenyl groups.

(Conventional Example 1) As a conventional example, a cyanophenyl ester compound was used instead of the compound group I,

[0030]

[Table 2]

A liquid crystal composition having the following composition was prepared and used in the following conventional examples 2 to 9.

(Example 2) In this example, a liquid crystal composition prepared in Example 1 was used to prepare a polymer particle alignment type display device, and its light resistance was examined.

96% by weight of the liquid crystal composition of Example 1, 0.5% by weight of chiral component R1011 (manufactured by Merck & Co.), 2
Color pigments (M361: SI512: M137 = 1.4% by weight: 1.7% by weight: 0.4% by weight, all manufactured by Mitsui Toatsu Dyes Co., Ltd.) were mixed to obtain 100% by weight. A mixture of 95% of this liquid crystal composition, 3.3% of terphenyl methacrylate and 1.7% of fluoroterphenyl dimethacrylate as a polymer precursor was sealed between two substrates with electrodes subjected to an alignment treatment. . An active element was formed on one of the two substrates. Active element is MIM element, T
A 640 × 480 display was possible with either FT element. Although the electrode on the back substrate is a reflective electrode, it may be a transparent electrode. In that case, the brightness is improved by disposing the reflection plate on the back side of the display element. The thickness of the liquid crystal layer was 5 μm,
It is preferable to optimize between 3 μm and 10 μm according to the application. This liquid crystal / polymer precursor mixed layer has a wavelength of 3 in the liquid crystal phase.
Ultraviolet rays having a wavelength of 00 nm to 400 nm and an intensity of 3.5 mW / cm 2 were irradiated to precipitate polymer particles from the liquid crystal. The surface of this display element was subjected to antiglare treatment and antireflection treatment. Of course, it is not necessary to perform such a treatment, and the visibility is sufficiently improved with only one of them.

A driving voltage of 5 V was applied to the liquid crystal / polymer layer of the display device thus manufactured, and the voltage was set to 2 from the normal line of the surface of the display device.
Brightness equivalent to that of white paper was obtained when light was incident from a direction inclined by 0 ° and the reflected light intensity in the normal direction was measured. When the white light was irradiated with a xenon lamp for 720 hours (integrated light amount of 20000 La), the retention rate was 70%.
Fell to.

In this embodiment, an example in which an active element is formed is shown, but of course the effect of a low driving voltage can be obtained without forming an active element.

(Conventional Example 2) When a display element having the structure of Example 2 was manufactured using the liquid crystal composition shown in Conventional Example 1 and the same light resistance test was conducted, the retention rate was 10% or less. .

(Embodiment 3) In this embodiment, an example in which the dichroic dye is not used in Embodiment 2 is shown. 99.5% by weight of the liquid crystal composition of Example 1 and 0.5% by weight of chiral component R1011 (manufactured by Merck) were mixed to make 100% by weight. A mixture of 95% of this liquid crystal composition, 3.3% of terphenyl methacrylate and 1.7% of fluoroterphenyl dimethacrylate as a polymer precursor was sealed between two substrates with electrodes subjected to an alignment treatment. . An active element was formed on one of the two substrates. Both the MIM element and the TFT element could be displayed as 640 × 480 active elements. Although the electrode on the back substrate is a reflective electrode, it may be a transparent electrode. In that case, visibility is improved by disposing a reflection plate or a light absorption plate on the back side of the display element.
Although the thickness of the liquid crystal layer is set to 5 μm, it is preferable to optimize the thickness between 3 μm and 10 μm according to the application. The liquid crystal / polymer precursor mixed layer has a liquid crystal phase with a wavelength of 300 nm to 400 n.
Ultraviolet rays having an intensity of m and an intensity of 3.5 mW / cm 2 were irradiated to precipitate polymer particles from the liquid crystal. The surface of this display element was subjected to antiglare treatment and antireflection treatment. Of course, it is not necessary to perform such a treatment, and the visibility is sufficiently improved with only one of them.

A driving voltage of 5 V was applied to the liquid crystal / polymer layer of the display device thus manufactured, and the drive voltage was set to 2 from the normal line of the display device surface.
Brightness equivalent to that of white paper was obtained when light was incident from a direction inclined by 0 ° and the reflected light intensity in the normal direction was measured. When the white light was irradiated with a xenon lamp for 720 hours (integrated light amount of 20000 La), the retention rate was 80%.
Fell to.

In this embodiment, an example in which an active element is formed is shown, but of course the effect of a low driving voltage can be obtained without forming an active element.

(Conventional Example 3) When a display element having the structure of Example 3 was prepared using the liquid crystal composition of Conventional Example 1 and the same light resistance test was conducted, the retention rate was 20% or less.

(Example 4) In this example, a polymer gel network alignment type liquid crystal display device was produced using the liquid crystal composition of Example 1 and its light resistance was examined.

96% by weight of the liquid crystal composition of Example 1, 0.5% by weight of chiral component R1011 (manufactured by Merck & Co.), 2
Color pigments (M361: SI512: M137 = 1.4% by weight: 1.7% by weight: 0.4% by weight, all manufactured by Mitsui Toatsu Dyes Co., Ltd.) were mixed to obtain 100% by weight. 97% of this liquid crystal composition and C6H as a polymer precursor

[0043]

[Chemical 17]

A mixture of 3% and Irgacure 651 (manufactured by Ciba Geigy) as a photopolymerization initiator was sealed between two orientation-treated substrates with electrodes. An active element was formed on one of the two substrates. 640 × 4 active elements for both MIM element and TFT element
80 indications were possible. Although the electrode on the back substrate is a reflective electrode, it may be a transparent electrode. In that case, the brightness is improved by disposing the reflection plate on the back side of the display element. Although the thickness of the liquid crystal layer is set to 5 μm, it is preferable to optimize the thickness between 3 μm and 10 μm according to the application. This liquid crystal / polymer precursor mixed layer was irradiated with ultraviolet rays having a wavelength of 300 nm to 400 nm and an intensity of 3.5 mW / cm 2 in the liquid crystal phase to form a polymer gel network in the liquid crystal. The surface of this display element was subjected to antiglare treatment and antireflection treatment. Of course, it is not necessary to perform such a treatment, and the visibility is sufficiently improved with only one of them.

A driving voltage of 10 V was applied to the liquid crystal / polymer layer of the display device thus manufactured, and light was incident from a direction inclined by 20 degrees from the normal line of the display device surface, and the reflected light intensity in the normal direction was obtained. When measured, the same brightness as white paper was obtained. When the white light was irradiated with a xenon lamp for 720 hours (total light amount: 20000 La), the retention rate was 60%.
Fell to%.

In this embodiment, an example in which an active element is formed is shown, but of course the effect of a low driving voltage can be obtained without forming an active element.

(Conventional Example 4) When a display element having the structure of Example 4 was prepared using the liquid crystal composition of Conventional Example 1 and the same light resistance test was conducted, the retention rate was 5% or less.

(Embodiment 5) In this embodiment, an example in which the dichroic dye is not used in Embodiment 4 is shown. 99.5% by weight of the liquid crystal composition of Example 1 and 0.5% by weight of chiral component R1011 (manufactured by Merck) were mixed to make 100% by weight. Two 97% liquid crystal compositions, 3% C6H shown above as a polymer precursor, and Irgacure 651 (manufactured by Ciba Geigy) as a photopolymerization initiator were mixed, and two substrates with electrodes were subjected to an alignment treatment. Enclosed in between. An active element was formed on one of the two substrates. Either MIM element or TFT element as active element is 640 × 48
It was possible to display 0. Although the electrode on the back substrate is a reflective electrode, it may be a transparent electrode. In that case, visibility is improved by disposing a reflection plate or a light absorption plate on the back side of the display element. The thickness of the liquid crystal layer was set to 5 μm, but from 3 μm to 10 μm
It is advisable to optimize between μm according to the application. This liquid crystal /
The polymer precursor mixed layer has a wavelength of 300 nm to 40 in the liquid crystal phase.
The polymer gel network was formed in the liquid crystal by irradiating with ultraviolet rays of 0 nm and an intensity of 3.5 mW / cm 2. The surface of this display element was subjected to antiglare treatment and antireflection treatment. Of course, it is not necessary to perform such a treatment, and the visibility is sufficiently improved with only one of them.

A driving voltage of 10 V is applied to the liquid crystal / polymer layer of the display device thus manufactured, and light is incident from a direction inclined by 20 degrees from the normal line of the display device surface, and the reflected light intensity in the normal line direction is obtained. When measured, the same brightness as white paper was obtained. When a white light was irradiated for 720 hours (integrated light quantity of 20000 La) with a xenon lamp, the retention rate was 70%.
Fell to%. The holding ratio is the ratio of the voltage held between the liquid crystals 50 milliseconds after the electric field of 10 V is applied to the liquid crystal after applying the electric field of 10 V for 60 μs and then returned to 0.

In this embodiment, an example in which the active element is formed is shown, but of course, the effect of a low driving voltage can be obtained without forming the active element.

(Conventional Example 5) When a display element having the structure of Example 5 was produced using the liquid crystal composition of Conventional Example 1 and the same light resistance test was conducted, the retention rate was 10% or less.

(Embodiment 6) In this embodiment, an example in which the liquid crystal composition shown in Embodiment 1 is used in a fine droplet matrix type display device will be described.

The liquid crystal composition of Example 1 was mixed with 1% of the dichroic dye described in Example 2 and the ultraviolet curable resin NOA65 (manufactured by Norland Co.) at a ratio of 1.6: 1. Stir at room temperature until a clear solution is obtained. This solution was sealed between two substrates with electrodes. An active element was formed on one of the two substrates. Both the MIM element and the TFT element could be displayed as 640 × 480 active elements. Although the electrode on the back substrate is a reflective electrode, it may be a transparent electrode. In that case, the visibility is improved by disposing the reflection plate on the back side of the display element. When the reflecting surface was formed so as to scatter light, the visibility was improved. The thickness of the liquid crystal layer is set to 15 μm, but it may be optimized between 5 μm and 20 μm according to the application. In the liquid crystal / polymer precursor mixed layer, the liquid crystal phase has a wavelength of 200 nm to 400 nm and an intensity of 20 m.
Ultraviolet rays of W / cm 2 were irradiated to form a structure in which fine liquid crystal droplets were dispersed in a polymer. The surface of this display element was subjected to antiglare treatment and antireflection treatment. Of course, it is not necessary to perform such a treatment, and the visibility is sufficiently improved with only one of them.

A driving voltage of 10 V was applied to the liquid crystal / polymer layer of the display element thus manufactured, and light was incident from a direction inclined by 20 degrees from the normal line of the display element surface, and the reflected light intensity in the normal direction was measured. When measured, the same brightness as white paper was obtained. When the white light was irradiated with a xenon lamp for 720 hours (total light amount: 20000 La), the retention rate was 60%.
Fell to%.

In this embodiment, an example in which an active element is formed is shown, but of course the effect of a low driving voltage can be obtained without forming an active element.

(Conventional Example 6) When a display element having the structure of Example 6 was prepared using the liquid crystal composition of Conventional Example 1 and the same light resistance test was conducted, the retention rate was 5% or less.

Although a dichroic dye is used in this embodiment, it functions as a display element without using it. At that time, the visibility is improved by using a reflective or light absorbing material for the forming electrode of the back substrate. Alternatively, a light reflection layer or a light absorption layer may be provided as a transparent electrode on the back surface of the display element.

Example 7 In this example, another example in which the liquid crystal composition shown in Example 1 is used in a fine liquid crystal matrix type display device will be described.

A mixture of the liquid crystal composition shown in Example 1 and 1% of the dichroic dye shown in Example 2 was used at room temperature together with Epicoat 828 and Capcure 3-800 (both manufactured by Yuka Shell Co., Ltd.). Stirred at a ratio of: 1: 1 until a clear solution was obtained. Then, quickly fill the empty cells shown below. Two glass substrates with electrodes were made to face each other so that the gap between them was 5 μm and the periphery was molded to form an empty cell. An electrode formed on one substrate was a transparent electrode, and an active element was formed on the other substrate, and then a light-scattering reflective electrode was formed. The light-scattering reflective electrode was formed by co-evaporating aluminum and silicon.
A transparent electrode may be formed on two substrates and a light scattering layer may be arranged on the back surface of the display element. The liquid crystal-polymer precursor mixture was sealed in the empty cell thus prepared, and then heated to 100 ° C. to accelerate curing. Thus, a structure in which fine liquid crystal droplets were dispersed in the polymer was formed. The surface of this display element was subjected to antiglare treatment and antireflection treatment. Of course, it is not necessary to perform such a treatment, and the visibility is sufficiently improved with only one of them.

A driving voltage of 10 V was applied to the liquid crystal / polymer layer of the display element thus manufactured, and light was incident from a direction inclined by 20 degrees from the normal line of the display element surface, and the reflected light intensity in the normal direction was obtained. When measured, the same brightness as white paper was obtained. When the white light was irradiated with a xenon lamp for 720 hours (total light amount: 20000 La), the retention rate was 50%.
Fell to%.

In this embodiment, an example in which an active element is formed is shown, but of course the effect of a low drive voltage can be obtained without forming an active element.

Although a dichroic dye is used in this example, it functions as a display element without using it. At that time, the visibility is improved by using a reflective or light absorbing material for the formation electrode on the back substrate. Alternatively, a light reflection layer or a light absorption layer may be provided as a transparent electrode on the back surface of the display element.

(Conventional Example 7) When a display element having the structure of Example 7 was prepared using the liquid crystal composition of Conventional Example 1 and the same light resistance test was conducted, the retention rate was 3% or less.

(Embodiment 8) This embodiment shows still another example in which the liquid crystal composition shown in Embodiment 1 is used for a fine liquid crystal matrix type display device. 5 g of the liquid crystal composition prepared in Example 1 mixed with 2% of the dichroic dye shown in Example 2
For 20 minutes at room temperature with 15 g of 20% PVA aqueous solution.
It was stirred at 00 rpm. The obtained solution was degassed for 24 hours, and dried to form a film having a thickness of about 10 μm on a glass substrate with active elements and pixel electrodes. After that, it was dried at 85 ° C. for 24 hours, and the counter substrate with electrodes was laminated. At this time, they may be laminated in a vacuum, or they may be laminated at normal pressure through a liquid crystal. Thus, a structure in which fine liquid crystal droplets were dispersed in the polymer was formed. The surface of this display element was subjected to antiglare treatment and antireflection treatment. Of course, it is not necessary to perform such a treatment, and the visibility is sufficiently improved with only one of them.

A driving voltage of 10 V was applied to the liquid crystal / polymer layer of the display element thus manufactured, and light was incident from a direction inclined by 20 degrees from the normal line of the display element surface, and the reflected light intensity in the normal direction was measured. When measured, the same brightness as white paper was obtained. When the white light was irradiated with a xenon lamp for 720 hours (total light amount: 20000 La), the retention rate was 80%.
Fell to%.

In this embodiment, an example in which an active element is formed has been shown, but of course the effect of a low driving voltage can be obtained without forming an active element.

Although a dichroic dye is used in this embodiment, it functions as a display element without using it. At that time, the visibility is improved by using a reflective or light absorbing material for the formation electrode on the back substrate. Alternatively, a light reflection layer or a light absorption layer may be provided as a transparent electrode on the back surface of the display element.

(Conventional Example 8) When a display element having the structure of Example 8 was produced using the liquid crystal composition of Conventional Example 1 and the same light resistance test was conducted, the retention rate was 10% or less.

Example 9 In this example, a polymer network type display device was produced using the liquid crystal composition shown in Example 1. A mixture of the liquid crystal composition shown in Example 1 with 2% of the dichroic dye shown in Example 1, a polymer precursor trimethylolpropane and a photopolymerization initiator 2-hydroxy-2-methyl-1- Phenylpropan-1-one was mixed in a ratio of 80: 19.8: 0.2 and stirred,
It was enclosed in an empty cell described later. Two glass substrates with electrodes were made to face each other so that the gap between them was 5 μm and the periphery was molded to form an empty cell. An electrode formed on one substrate was a transparent electrode, and an active element was formed on the other substrate, and then a light-scattering reflective electrode was formed. The light-scattering reflective electrode was formed by co-evaporating aluminum and silicon. A transparent electrode may be formed on two substrates and a light scattering layer may be arranged on the back surface of the display element. After filling the liquid crystal-polymer precursor mixture into the empty cell thus prepared, the polymer precursor was separated by a halogen lamp (70 W / cm2). Thus, a structure in which fine liquid crystal droplets were dispersed in the polymer was formed. The surface of this display element was subjected to antiglare treatment and antireflection treatment. Of course, it is not necessary to perform such a treatment, and the visibility is sufficiently improved with only one of them.

A driving voltage of 10 V was applied to the liquid crystal / polymer layer of the display element thus manufactured, and light was made incident from a direction inclined by 20 degrees from the normal line of the display element surface, and the reflected light intensity in the normal line direction was measured. When measured, the same brightness as white paper was obtained. When the white light was irradiated with a xenon lamp for 720 hours (total light amount: 20000 La), the retention rate was 50%.
Fell to%.

In this embodiment, the example in which the active element is formed is shown, but of course, the effect of the low driving voltage can be obtained without forming the active element.

Although the dichroic dye is used in this embodiment, it functions as a display element without using it. At that time, the visibility is improved by using a reflective or light absorbing material for the formation electrode on the back substrate. Alternatively, a light reflection layer or a light absorption layer may be provided as a transparent electrode on the back surface of the display element.

In all of the above examples, the thickness of the liquid crystal / polymer layer may be determined according to the application. If it is thick, light absorption or light scattering will be strong, but the driving voltage will be high, and it will not be possible to drive with an active element or driver IC.
If it is thin, it can be driven by an active element or a driver IC, but light absorption or light scattering becomes weak.

(Conventional Example 9) When a display element having the structure of Example 9 was produced using the liquid crystal composition of Conventional Example 1 and the same light resistance test was conducted, the retention rate was 3% or less.

Example 10 In this example, an example in which the compound group I is replaced with the compound group II in Example 1 will be shown.

[0076]

[Table 3]

Using this liquid crystal composition, a display element was manufactured according to Example 3. According to this, compared to the third embodiment,
The scattering degree was about 90% and the driving voltage was increased by 10%, but the light resistance was increased by 10%.

Although the application to the configuration of the third embodiment is shown here, the present invention is not limited to this, and the same can be applied to the configurations of the second to ninth embodiments.

(Example 11) This example shows an example in which the compound group I in Example 1 is replaced with the compound group III.

[0080]

[Table 4]

Using this liquid crystal composition, a display device was manufactured according to the example 4. According to this, compared with the case of Example 4, the scattering degree is improved by about 10% and the driving voltage is increased by about 10%, but the light resistance is the life of the identification degree.

Although the application to the configuration of the fourth embodiment is shown here, the present invention is not limited to this, and the same can be applied to the configurations of the second to ninth embodiments.

Example 12 In this example, an example in which the compound group I is replaced with the compound group IV in Example 1 will be shown.

[0084]

[Table 5]

Using this liquid crystal composition, a display element was manufactured according to the example 5. According to this, compared to the case of Example 5, the driving voltage is increased by about 10% due to the scattering degree of the identification degree, but the light resistance is the life of the identification degree.

Although the application to the configuration of the fifth embodiment is shown here, the present invention is not limited to this, and the same can be applied to the configurations of the second to ninth embodiments.

Example 13 In this example, an example in which the compound group I in Example 1 is replaced with the compound group V is shown.

[0088]

[Table 6]

Using this liquid crystal composition, a display element was prepared according to Example 6. According to this, compared to the case of Example 6, the scattering degree is increased by 10% and the driving voltage is increased by about 10%, but the light resistance is the life of the identification degree.

Although the application to the configuration of the sixth embodiment is shown here, the present invention is not limited to this, and the same can be applied to the configurations of the second to ninth embodiments.

(Example 14) In this example, an example in which the compound group I and the compound groups VII and VIII shown above are mixed and used is shown. The composition of the liquid crystal used in this example is shown.

[0092]

[Table 7]

Using this liquid crystal composition, a display device was manufactured according to the seventh embodiment. According to this, compared to the seventh embodiment,
The scattering degree was reduced by about 10%, and the light resistance was the lifetime of the identification degree, but the driving voltage was reduced by about 10%.

Although the application to the configuration of the seventh embodiment is shown here, the present invention is not limited to this, and the same can be applied to the configurations of the second to ninth embodiments.

The R of each compound group is not limited to those shown here, but may be determined so as to have an optimum liquid crystal temperature range depending on the application. The mixing ratio of each compound group is not limited to the values shown here, and can be determined in consideration of the type and length of R, the operating temperature range required for the application, and the electro-optical characteristics.

Example 15 In this example, a compound group II is used in place of the compound group I in Example 14.

[0097]

[Table 8]

Using this liquid crystal composition, a display device was manufactured according to Example 8. According to this, compared with Example 8, the scattering degree is about 80% and the driving voltage is about 10% higher.
The light resistance was increased by 10%.

Although the application to the configuration of the eighth embodiment is shown here, the present invention is not limited to this and can be similarly applied to the configurations of the second to ninth embodiments.

Example 16 In this example, a compound group III is used instead of the compound group I in Example 14.

[0101]

[Table 9]

Using this liquid crystal composition, a display element was prepared according to Example 9. According to this, compared with the ninth embodiment,
The degree of scattering is about the same and the driving voltage is increased by about 10%, but the light resistance is increased by 10%.

Although the application to the configuration of the ninth embodiment is shown here, the present invention is not limited to this, and the same can be applied to the configurations of the second to eighth embodiments.

Example 17 In this example, a compound group IV is used instead of the compound group I in Example 14.

[0105]

[Table 10]

Using this liquid crystal composition, a display device was manufactured according to the second embodiment. According to this, compared with Example 2, the scattering degree was about 90%, the driving voltage and the light resistance were about the same.

Although the application to the configuration of the second embodiment is shown here, the present invention is not limited to this, and the same can be applied to the configurations of the third to eighth embodiments.

Example 18 In this example, an example in which the compound group I in Example 14 is replaced with the compound group V will be shown.

[0109]

[Table 11]

Using this liquid crystal composition, a display element was manufactured according to the example 3. According to this, compared to the case of Example 3, the scattering degree was about the same and the driving voltage was increased by about 10%, but the light resistance was the life of the identification degree.

Although the application to the configuration of the third embodiment is shown here, the present invention is not limited to this, and the same can be applied to the configurations of the second to eighth embodiments.

[0112]

As described above, according to the present invention, it is possible to obtain a low driving voltage by using a liquid crystal in which the above-mentioned additive compound for liquid crystal is mixed in the polymer dispersion type liquid crystal display device or the polymer orientation dispersion type liquid crystal display device. It was possible to achieve both light resistance. As a result, it can be used as a display device of a portable information device that is often used outdoors. It has also become easy to fabricate a highly reliable large-capacity reflective display. It can also be used for outdoor advertising boards.

Front Page Continuation (72) Inventor Hidehito Iizaka 3-3-5 Yamato, Suwa-shi, Nagano Seiko Epson Corporation

Claims (3)

[Claims] 1. A liquid crystal composition used in a display device in which a polymer and a liquid crystal are dispersed or alignment dispersed in each other, and a compound group I (R is an alkyl group or an alkoxy group) Compound group II (R is an alkyl group or an alkoxy group) Compound group III (R is an alkyl group or an alkoxy group) Compound group IV (R is an alkyl group or an alkoxy group) Compound group V A liquid crystal composition comprising at least one compound of a compound group represented by (R is an alkyl group or an alkoxy group), and the composition ratio of these compound groups is 5% by weight to 50% by weight. 2. The compound group VI embedded image in the liquid crystal g composition. (R is an alkyl group or an alkoxy group) Compound group VII (R is an alkyl group or an alkoxy group) Compound group VII
I (R is an alkyl group or an alkoxy group, R1 is fluorine or hydrogen, and R2 is a fluorine or an alkyl group) 5 to 90% of at least one compound group is contained. Liquid crystal composition. 3. The liquid crystal composition according to claim 1, wherein the liquid crystal composition contains a dichroic dye.