JPH08320505A - Liquid crystal display device - Google Patents

Abstract

PURPOSE: To obtain a liquid crystal display device of a novel system having a high contrast and a wide effective visual field by coloring particulates, dispersing these particulates into liquid crystals and making display. CONSTITUTION: Colored regions 2 are formed by coloring part of the particulates dispersed into liquid crystal molecules. Transparent electrodes 5 consisting of ITO, etc., are formed on transparent substrates 4 consisting of glass, etc., of the display device formed by dispersing such particulates into the liquid crystals held between the two substrates 4. Oriented films 6 for orienting the liquid crystal molecules 3 in specified directions are formed on these transparent electrodes 5. Two sheets of such substrates 4 are arranged to face each other and the liquid crystals 3 dispersed with the particulates are held between the substrates 4. This liquid crystal display device exhibits a scattering state or transparent state and displays white when voltage is not impressed thereon. The liquid crystal molecules, thereupon, rise and simultaneously the particulates respond to the liquid crystal molecules 3 and change the direction by directing the colored regions 2 toward the substrate 4 side, thereby displaying black when the voltage is impressed between the transparent electrodes 5 of the liquid crystal cell.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a liquid crystal display device.

[0002]

2. Description of the Related Art A liquid crystal display device has been attracting attention as a display device for a portable terminal because it can be easily made thin and driven at a low voltage. The twisted nematic liquid crystal display device (TNLCD), which is widely used at present, can have display characteristics similar to that of a CRT by incorporating an active switch element such as a TFT, but since a polarizing plate is used, the light utilization efficiency is improved. Is bad and needs a backlight.

In a display device which requires such a backlight, the power consumption of the backlight is large and it is not suitable for portable use. Therefore, a display method having higher light utilization efficiency than TNLCD is desired. A guest-host liquid crystal display (GHLCD) is a candidate for this system. This is to mix the dichroic dye in the oriented liquid crystal and control the direction of the dichroic dye molecule according to the response of the liquid crystal due to the external field. Since this display method basically does not require a polarizing plate, it has high light utilization efficiency and is expected as a reflective display method.

However, the current GHLCD has a low contrast due to factors such as the fact that the dye can be dissolved in the liquid crystal in only a few percent and the absorption axis of the liquid crystal is uniaxial so that it can absorb only half of the total amount of light at the maximum. However, in reality, it is not used in an actual display device.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a liquid crystal display having sufficiently high light utilization efficiency and sufficiently high contrast to be used in a reflective display system. The purpose is to provide a device. Another object of the present invention is to provide a liquid crystal display device having a wide effective viewing angle.

[0006]

In order to achieve the above object, a liquid crystal display device according to the present invention comprises a substrate, a liquid crystal material disposed on the substrate, and fine particles dispersed in the liquid crystal material. Liquid crystal driving means for changing the arrangement direction of liquid crystal molecules in the liquid crystal material, and changing the orientation of the fine particles in response to a change in the arrangement of the liquid crystal molecules driven by the liquid crystal driving means. It is characterized by.

Further, the liquid crystal display device according to the present invention is characterized in that at least a part of the fine particles is colored or absorbs light of a specific wavelength. Further, in the liquid crystal display device according to the present invention, the surface of the fine particles is divided into first and second regions having different surface tensions, the surface tension of the first region is γ1, and the surface tension of the second region is γ2. When the surface tension of the liquid crystal material is γLC, γ1>γLC> γ2 is satisfied.

Further, the liquid crystal display device according to the present invention is characterized in that the liquid crystal molecules are uniformly aligned on the surfaces of the fine particles. The liquid crystal display device according to the present invention is characterized in that the fine particles have a spherical shape.

Further, the liquid crystal display device according to the present invention is characterized in that the shape of the fine particles is anisotropic. Further, the liquid crystal display device according to the present invention is characterized in that the fine particles have a plate shape.

In the liquid crystal display device according to the present invention, a substrate, an accommodating member disposed on the substrate for accommodating a liquid crystal material therein, a supporting member for movably supporting the accommodating member, and the accommodating member among the accommodating members are included. A liquid crystal driving unit that changes the alignment direction of liquid crystal molecules in the liquid crystal material, and the orientation of the containing member changes in response to a change in the alignment of the liquid crystal molecules driven by the liquid crystal driving unit. It is characterized by that.

The liquid crystal display device according to the present invention is characterized in that a part of the housing member is colored or absorbs or scatters light of a specific wavelength. The liquid crystal display device according to the present invention is characterized in that the supporting member is made of a liquid crystal material.

The liquid crystal display device according to the present invention is characterized in that the shape of the housing member is anisotropic. Further, in the liquid crystal display device according to the present invention, the liquid crystal driving means applies a voltage between a pair of electrodes formed substantially parallel to the substrate surface and a pair of electrodes provided substantially perpendicular to the substrate surface. The direction of the accommodating member is controlled by.

The liquid crystal display device according to the present invention is characterized in that the fine particles are movable in a fixed direction with respect to a fulcrum fixed to the substrate. The liquid crystal display device according to the present invention is characterized in that the liquid crystal material in which the fine particles are dispersed, the liquid crystal material contained in the containing member, or the liquid crystal material used as the supporting member contains a dichroic dye. To do.

Further, in the liquid crystal display device according to the present invention, the liquid crystal driving means applies a voltage between a pair of electrodes formed substantially parallel to the substrate surface and a pair of electrodes provided substantially perpendicular to the substrate surface. By applying the voltage, the direction of the containing member is controlled.

The liquid crystal display device according to the present invention is characterized in that the fine particles or the accommodating member are movable in a fixed direction with respect to a fulcrum fixed to the substrate.

In the liquid crystal display device according to the present invention, the liquid crystal material in which the fine particles are dispersed, the liquid crystal material contained in the containing member, or the liquid crystal material used as the supporting member contains a dichroic dye. It is characterized by.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is adapted to the alignment of liquid crystals.
The fine particles dispersed in the liquid crystal respond and change the direction to exhibit a dimming effect and display.
For the fine particles, for example, a material that scatters or transmits light is used. Then, a region for absorbing or coloring light is provided in a part of the fine particles so that the direction of scattering or transmitting light, or the direction of absorbing or coloring light is shown depending on the viewing direction.

By dispersing the fine particles in a liquid crystal material and changing the alignment direction of the liquid crystal molecules by, for example, an external electric field, the direction of the fine particles can be changed, and light transmission or coloring can be selected and displayed.

FIG. 1 shows the shape of fine particles dispersed in liquid crystal molecules. The fine particles 1 have a projected shape that is almost spherical on all surfaces, when projected. The matrix of the particles is made of a material that scatters or transmits light, and a material that appears white or transparent can be used. Part of the fine particles 1 is colored so that the light is colored or transmitted depending on the viewing direction.
Is formed. By doing so, the light is observed in a colored state, that is, black from the direction of the arrow A, and the light is transmitted or scattered, that is, white, from the direction of the arrow B.

When observing the fine particles as a large number of aggregates, if all the fine particles are aligned with the colored region 2 facing, observing from the direction A, black is displayed and B
When viewed from the direction, the display will show white.

A state in which the fine particles 1 are dispersed in liquid crystal molecules is shown in FIG. In this case, the surface of the fine particles 1 is divided into regions having different surface tensions. For example, the surface tension of the colored region 2 is γ1, and the uncolored region (non-colored region).
Letting γ2 be the surface tension of γ2 and γLC be the surface tension of the liquid crystal material, there is a relation of γ1>γLC> γ2 (1). In the relation of this expression (1), the liquid crystal molecules 3 are oriented so that the molecular length stands in the colored region and aligned in the non-colored region so that they are aligned in the surface, and thus are energy-stable.

By thus selecting the surface tension of a part of the fine particles, it is possible to easily control the direction of the fine particles in the liquid crystal material, and it is possible to easily obtain the directionality of the fine particles and improve the contrast.

Further, by making the fine particles spherical, it is possible to further reduce the resistance received from the dispersed liquid crystal material when the fine particles change direction in the liquid crystal material. This can improve the response speed.

Next, FIG. 9 schematically shows a display device in which the fine particles are dispersed in a liquid crystal sandwiched between two substrates. A transparent electrode 5 such as ITO is formed on a transparent substrate 4 such as glass, and an alignment film 6 for aligning the liquid crystal molecules 3 in a certain direction is formed on the transparent electrode 5. The two substrates are opposed to each other, and the liquid crystal 3 in which the fine particles 1 are dispersed is sandwiched between the substrates. Now, this liquid crystal display device shows a scattering or transparent state in which no voltage is applied and displays white.
When a voltage is applied between the transparent electrodes of this liquid crystal cell, the liquid crystal molecules rise, and at the same time, the fine particles 1 also respond to the liquid crystal molecules 3 to turn the colored regions 2 toward the substrate side and display black.

FIG. 10 shows the relationship between the fine particles and the liquid crystal molecules when the relationship between the surface tension γ1 of the colored area, the surface tension γ2 of the non-colored area, and the surface tension γLC of the liquid crystal material is γ1 <γLC <γ2 (2). Is shown. That is, the long axes of the liquid crystal molecules are aligned with respect to the colored regions 1, and the liquid crystal molecules stand on the surface of the colored regions in the non-colored regions. In this case, a black display is shown when no voltage is applied, and a white display is shown even when a voltage is applied.

In this embodiment, since the fine particles are spherical, the particles can easily change their directions, and the resistance received from the surrounding liquid crystal during rotation is small, so that a good response can be expected. FIG.
Shows the shape of another fine particle of the present invention. The fine particles 1 are cubic and one surface thereof is colored. When observed from the direction of arrow A, the fine particles show a colored state (black), and when observed from the direction of arrow B, they show a transparent or scattered state (white).

Here, the alignment state between the liquid crystal molecules and the fine particles when the relationship of the surface tension γ1 of the colored region, the surface tension γ2 of the non-colored region, and the surface tension γLC of the liquid crystal material shows the formula (1) is shown. 4 shows. Such fine particles are shown in FIG. 9 or FIG.
The display device of the present invention can be obtained by dispersing it in the liquid crystal cell 0.

In the present embodiment, the fine particles have a cubic shape, so that they are close to spherical in shape, and the resistance from the liquid crystal material can be reduced as described above. Furthermore, when white is displayed, no black surface is observed at all, and when black is displayed, white is not observed, so that it is possible to further improve the contrast.

FIG. 5 shows the shape of another fine particle of the present invention.
The fine particles 1 have a circular plate-like form (on a disk), and all surfaces are colored. In this case, the area ratio of the main surface to the side surface is 2: 1 or more, the fine particles show a colored state (black) when observed from the direction of arrow A, and the colored region on the side surface when observed from the direction of arrow B It is hardly observed by human eyes and shows a transparent or scattered state (white). Further, in this case, only the main surface of the fine particles may be colored and the side surface may be colored.

Next, the alignment state of the liquid crystal molecules and the fine particles in the case where the relationship among the surface tension γ1 of the colored area on the main surface, the surface tension γ2 of the side surface, and the surface tension γLC of the liquid crystal material shows the formula (2) is shown. As shown in FIG.

FIG. 11 shows a liquid crystal display device in which such fine particles are dispersed in liquid crystal molecules and sandwiched between substrates with electrodes. A transparent electrode 5 such as ITO is formed on a transparent substrate 4 such as glass, and an alignment film 6 for aligning the liquid crystal molecules 3 in a certain direction is formed on the transparent electrode 5.
The two substrates are opposed to each other, and the liquid crystal 3 in which the fine particles 1 are dispersed is sandwiched between the substrates. Now, this liquid crystal display device shows a colored state (black) when no voltage is applied.
When a voltage is applied between the transparent electrodes of the liquid crystal cell, the liquid crystal molecules rise, and at the same time, the fine particles 1 respond to the liquid crystal molecules 3 and turn their side faces toward the substrate side to display a white display.

In this embodiment, by making the fine particles into a disc shape, the strength of the particles can be improved and the display stability can be realized. Further, since the fine particles 1 have a shape having anisotropy in one direction, those having a particularly uniform surface (having a uniform surface tension)
Can also respond to liquid crystal molecules.

FIG. 7 shows the shape of another fine particle of the present invention.
The fine particles 1 have a cylindrical shape and their end faces are colored. When observed from the direction of arrow A, the fine particles show a colored state (black), and when observed from the direction of arrow B, they show a transparent or scattered state (white).

Here, the alignment state between the liquid crystal molecules and the fine particles when the relationship among the surface tension γ1 of the colored region, the surface tension γ2 of the non-colored region, and the surface tension γLC of the liquid crystal material shows the formula (1) is shown. 8 shows. Such fine particles are shown in FIG. 9 or FIG.
The display device of the present invention can be obtained by dispersing it in the liquid crystal cell 0. Further, the side faces of the present fine particles may be colored, and the end faces may be non-colored regions.

In this embodiment, the fine particles have the same cylindrical shape as the liquid crystal molecules, so that the response to the liquid crystal molecules can be improved and the alignment can be easily controlled. Further, similar to the above-mentioned cube, it is possible to display perfect black and perfect white, so that it has a feature of high contrast.

Further, since the fine particles have a shape having anisotropy in one direction, even those having a uniform surface (having a uniform surface tension) can respond to liquid crystal molecules. When the fine particles are formed of a transparent material, white display may be performed by looking at the back scattering plate formed on the substrate in the white mode. Further, the liquid crystal molecule may be anything as long as it has anisotropy in shape, dielectric constant and refractive index and can respond to an external field.
When a liquid crystal having a positive dielectric constant with respect to the electric field is used, the long axis of the liquid crystal faces the electric field direction, and when using a negative liquid crystal with respect to the electric field, the short axis of the liquid crystal faces the electric field direction.

Further, as in the present invention, since a part of the fine particles is colored, all the light incident on this colored surface is absorbed or colored regardless of the direction of the vibration axis. Therefore,
The black level is remarkably improved as compared with the guest host method, and display with high contrast can be realized.

In the present invention, the particle size is preferably such that the maximum external dimension is in the range of 500 angstroms or more and 10 μm or less. If it is less than 500 Å, the shape and size of the colored particles cannot be sufficiently controlled,
If it is larger than m, it is too large to respond with the liquid crystal,
Further, there is a problem in reducing the gap of the liquid crystal cell due to the low voltage driving.

The specific gravity of the particles is preferably substantially the same as that of the liquid crystal. When the display panel is used in an upright state when the specific gravities are different, for example, when the particles are heavy, the particles accumulate in the lower part of the panel, and the density of the particles on the display screen deviates.

It is effective to provide a wall as a threshold between the pixels or to provide a small room in smaller units. The electrodes of the present invention can be provided parallel to the substrate or on the wall provided as the threshold and perpendicular to the substrate.

If the inter-substrate gap is large, the density of the fine particles may deviate in the cross-sectional direction of the cell.
By separating the liquid crystal display unit into two or more layers, it becomes possible to eliminate the deviation. Further, by separating the liquid crystal display portion into two or more layers and dispersing the fine particles in each layer, light can be incident on the liquid crystal layers, so that the contrast can be further improved.

Further, by making the color of fine particles different depending on the display color of each display pixel, color display is possible. Color display can also be performed by providing a color filter separately on the substrate.

In order to widen the effective viewing angle in the halftone, it is effective to have the rising directions of the liquid crystal molecules in two or more directions within the display surface. By regulating the rising direction of the liquid crystal molecules to one side, it is possible to smoothly rotate the fine particles along the rising direction, but there is a problem that a brightness difference occurs depending on the viewing direction. Therefore, in order to eliminate the difference depending on the viewing direction, it is preferable to use a multi-domain method in which the rising directions of the liquid crystal molecules have all directions in the plane.
In the case of the multi-domain system, disclination at the domain boundary is often a problem, but in the present invention, since a polarizing plate is not necessary, it does not affect the image quality.

Further, in the present invention, it is effective that the liquid crystal in which the fine particles are dispersed contains the dichroic dye used in the conventional GHLCD. Since both the fine particles and the dichroic dye can absorb light, the contrast can be further improved. Furthermore, not only this absorption effect, but because the orientation field is disturbed by the fine particles, it is possible to efficiently absorb the dichroic dye that has only one axis of absorption, in all directions,
It leads to further improvement of the light absorption effect.

The fine particles used in the present invention are movable in a fixed direction with respect to a fulcrum fixed to the substrate. If the liquid crystal is sandwiched between the substrates and the fine particles are simply dispersed in the liquid crystal, the fine particles may agglomerate, the in-plane density of the fine particles may be biased, or the fine particles may be adsorbed to the substrate interface to operate the fine particles. Sometimes you can't. Therefore, a part of the fine particles is movably fixed to a fulcrum fixed to the substrate,
It can operate well if it can be moved in a certain direction.

FIG. 19 shows a state of the liquid crystal display device having the fine particles 1 movably fixed to the fulcrum 9 fixed to the substrate 4. When a voltage is thus applied between the electrodes 6, the liquid crystal 3 rises with respect to the substrate, and in response thereto, the fine particles 1 rise. When the voltage is turned off, the liquid crystal 1 returns to be parallel to the substrate, and the fine particles 1 also respond to this and move with respect to the fulcrum 1 so as to be parallel to the substrate.

In such a structure, since the fine particles 1 are fixed to the fulcrum 9, there is no problem that the fine particles aggregate. As the shape of the fine particles, as shown in FIG. 20, a shape in which a shaft 10 for fixing to a fulcrum is formed on a spherical fine particle 1 can be mentioned. If necessary, coloring 2 is applied to a part of the direction rotatable with respect to the shaft 10. Thus, the shape of the fine particles may not have anisotropy, but in that case, it is necessary to locally change the alignment state of the liquid crystal.

Further, as shown in FIG. 21, the shape of the fine particles can be plate-like. In this way, since the shape is anisotropic with respect to the axis 10, the most energy-stable arrangement can be taken according to the orientation of the liquid crystal.

As shown in FIG. 4, when the shape of the fine particles is cylindrical and the axis is in a rotationally symmetric position about one axis, FIG.
It is close to the spherical shape shown in. Further, as shown in FIG. 23, when the shape of the fine particles is columnar, the shape is anisotropic with respect to the axis 10 to some extent, so that a stable arrangement can be taken according to the orientation of the liquid crystal.

Further, as shown in FIG. 24, an axis may be provided on one side of the plate-like fine particles. In the case of fine particles having anisotropy in shape, the whole particles may be colored or the whole particles may be made to scatter light.

It is more preferable that the surface of the fine particles is oriented in a fixed direction so that the rising direction of the liquid crystal molecules is defined within the plane. This gives a more stable response.
Although any liquid crystal material may be used, it is more preferable that the liquid crystal material has a high dielectric anisotropy and has a strong alignment adsorptivity to the base material on the particle surface. Further, as described above, it is preferable that the surface is stably oriented in a fixed direction.

The anisotropic particles mentioned here are particles in which the projected shape obtained by projection is not exactly the same spherical shape on all surfaces, and the projected areas are not equal. It is more preferable that the projected area ratio is large depending on the viewing direction, as represented by a disk. Depending on the viewing direction, the disk has a direction that looks like a circle and a direction that looks like a long rectangle. The larger the disk diameter to thickness ratio, the larger the projected area ratio. Here, when the entire disk is colored black, the black area looks greatly different depending on the viewing direction, and when viewed as a group of disks in the macro, the contrast is effective as a display element determined by the projected area ratio. You can display in black and white.

When this disk is colored, it is possible to display with high contrast as described above. This is because the projected area ratio can be large, but basically,
Light incident on this colored surface is independent of the direction of the vibration axis.
It is largely due to the effect of being absorbed or colored. Also, the viewing angle dependence of the contrast is small.

The shape of the anisotropic particles is not limited to the disk shape, and any shape having a large projected area ratio can be used in the present invention. However, when the projected area ratio is 2: 1 or less, the contrast is insufficient and the response along the liquid crystal is not sufficient. Here, as the method of giving anisotropy, it is preferable to adopt a shape or a manufacturing method in which the liquid crystal is oriented in a fixed direction.

In the case of particles having no anisotropy in shape, it is preferable to provide a means for controlling the orientation of the liquid crystal on the surface thereof. For example, it may be possible to apply a voltage in a certain direction or to carry out an orientation treatment on a part of the particles when they are manufactured.
After that, the surface is colored in accordance with the orientation direction.

The particle size is such that the maximum external dimension is 0.5 μm.
It is desirable to be in the range of m to 100 μm. 0.5
If it is less than μm, the shape and size of particles cannot be sufficiently controlled, and if it is 100 μm or more, it is too large to respond,
There is also a problem in reducing the cell gap of the liquid crystal display element due to the low voltage driving.

Furthermore, by making the color of the particles different according to the display color of each display pixel, it is possible to perform color display. Color display is also possible when a color filter is used separately.

As described above in detail, in the liquid crystal display device of the present invention, good display with no display abnormality, high contrast and wide effective viewing angle can be performed. A liquid crystal display device according to another embodiment of the present invention will be described. In this embodiment, a microcapsule is used as a containing member for containing the liquid crystal inside, and the direction of the microcapsule is controlled by driving the liquid crystal from the outside, and display is performed by light transmission, absorption, and scattering. Is. That is, the liquid crystal in the microcapsule is oriented with respect to the inner wall of the microcapsule, and the microcapsule also changes its orientation in response to the liquid crystal changing its orientation by an external electric field.

In particular, when the liquid crystal is sandwiched between the substrates and the microcapsules are dispersed in the liquid crystal, the liquid crystal is oriented on the inner surface of the microcapsule, and the external liquid crystal which is a supporting member of the microcapsule is also the outer wall of the microcapsule. Since they are oriented with respect to each other, the internal liquid crystal and the external liquid crystal change their directions by the external electric field, and the microcapsules also change their directions, so that the response speed becomes faster.

Here, a part of the microcapsules may be colored or light-scattered, or the shape thereof may be made anisotropic so that it can be used as a light shutter in a display element. In FIG. 25, liquid crystal molecules 12 are housed in spherical microcapsules 11, and both electrodes are colored 2.

FIG. 26 shows a liquid crystal molecule 12 housed in a disk-shaped microcapsule 11. Further, FIG. 27 shows that liquid crystal molecules 1 are contained in a cylindrical microcapsule 11.
2 are housed.

In the case of coloring, it is preferable to color the extreme parts of the microcapsules. Further, in the case of a microcapsule having anisotropy in shape such as a disk shape or a cylindrical shape, the entire microcapsule may be colored, or liquid crystal and a pigment may be contained in the microcapsule for coloring. Similarly, in the case of performing light scattering treatment, the light scattering treatment can be performed on the poles of the microcapsules. When the shape has anisotropy, the entire microcapsule may be subjected to light scattering treatment.

The supporting member for supporting the microcapsule may be any member as long as it supports the microcapsule in a movable state, but a liquid one having a large dielectric constant and a small resistivity is preferable. Further, it is more preferable that the viscosity is low. Furthermore, by using liquid crystal as the supporting member, the liquid crystal inside the microcapsules as well as the external liquid crystal are oriented and adsorbed on the surface of the microcapsules, and this acts as a driving force for controlling the direction, so that the response speed is further improved.

When liquid crystal is used as a supporting member, it is necessary to align the substrates sandwiching the liquid crystal in a certain direction to define the rising direction of the liquid crystal molecules within the plane, so that the alignment distortion of the liquid crystal at the time of rising is small and the rising is good. It is more preferable because the characteristics are obtained and the response speed is fast.

Any liquid crystal material may be used, but a material having a high dielectric anisotropy and a strong orientation adsorptivity to the substrate on the surface of the microcapsules is preferable. Further, it is preferable that the surface is oriented in a fixed direction.

The anisotropic microcapsule mentioned here is a microcapsule whose projected shape when projected and transferred is not exactly the same spherical shape on all surfaces, and whose projected areas are not equal. It is more preferable that the projected area ratio is large depending on the viewing direction, as represented by a disk. Depending on the viewing direction, the disk has a direction that looks like a circle and a direction that looks like a long rectangle. The larger the disk diameter to thickness ratio, the larger the projected area ratio. When the entire disk is colored black here, the black area looks different depending on the viewing direction, and when viewed as a group of disks in the macro, the black and white display is effective as a display element whose contrast is determined by the projected area ratio. You can

In view of this, the present invention controls whether the circle of the disk is viewed or the thickness direction is viewed by changing the alignment of the liquid crystal. Liquid crystal molecules have anisotropy in shape, dielectric constant, and refractive index and can respond to an external field. When a liquid crystal having a positive dielectric constant is placed in the electric field, the long axis of the liquid crystal faces the electric field direction. Here, the surface tension of the disc and the surface tension of the liquid crystal determine whether the orientation of the disc surface of the liquid crystal is parallel or perpendicular to the disc surface. Therefore, if the surface tension of the disk is larger than the surface tension of the liquid crystal, the parallel alignment becomes stable.
As shown in FIG. 6, when the liquid crystal molecules are oriented in a certain direction, the disc also tries to orient the plane of the circle parallel to the long axis direction of the energy-stable liquid crystal. Therefore, the orientation of the disk will change according to the arrangement of the liquid crystals. This gives a better response when the disc is provided with an alignment property in which liquid crystals are arranged in a certain direction.

When this disk is colored, it is possible to display with high contrast as described above. This is because the projected area ratio can be large, but basically, all the light incident on this colored surface is absorbed or colored regardless of the direction of the vibration axis. Also, the viewing angle dependence of the contrast is small.

Here, the shape of the anisotropic microcapsules is not limited to the disk shape, and any shape having a large projected area ratio can be used in the present invention. However, when the projected area ratio is 2: 1 or less, the contrast is not sufficient and the response along the liquid crystal is not sufficient. Here, as a method of giving anisotropy, it is preferable to adopt a shape or a manufacturing method in which the orientation of the liquid crystal is fixed.

In the case of microcapsules having no shape anisotropy, it is preferable to provide a means for controlling the orientation of the liquid crystal. For example, it is possible to apply a voltage in a certain direction at the time of manufacturing the liquid crystal microcapsules, or to carry out an alignment treatment on a part thereof. After that, a treatment such as coloring of the surface is performed according to the orientation treatment direction.

The size of the microcapsules is preferably such that the maximum external dimension is in the range of 0.5 μm to 100 μm. If it is less than 0.5 μm, the shape and size of the microcapsule cannot be sufficiently controlled, and if it is 100 μm or more, it is too large to respond and it is difficult to reduce the cell gap of the liquid crystal display device for low voltage driving. .

It is desirable that the specific gravity of the microcapsules be substantially equal to that of the liquid crystal as the supporting member. If the specific gravities are different, the density of the microcapsules in the dispersion medium becomes uneven. As a countermeasure against this deviation, it is effective to provide a wall serving as a threshold between display pixels or to provide a small room in smaller units.

By separating the liquid crystal display portion into two or more layers, it is possible to prevent deviation between the upper and lower sides of the substrates, and it is possible to surely allow light to be incident on the two or more microcapsule layers. It is possible to raise. It is particularly preferable to provide a partition between each microcapsule. As a result, it is possible to completely prevent the aggregation that affects the display.

Further, by making the color of the microcapsule different according to the display color of each display pixel, color display can be made possible. Color display is also possible when a color filter is used separately.

A liquid crystal display device according to this example is shown in FIG. When driving this liquid crystal display device, the direction of the microcapsules 11 in the support member 6 is controlled by the direction of the electric field. In the microcapsule 1 provided between the electrodes 14 on the opposing substrate 4, the liquid crystal 12 changes its direction due to the electric field between the electrodes 14, and in response thereto, the direction changes. Since this directionality is maintained after removing the electric field between the electrodes,
Has memory.

On the contrary, when it is desired to change the direction by 90 degrees, a voltage is applied between the electrodes 15 provided on the substrate and capable of forming an electric field in the vertical direction. In this case, the two pairs of electrodes 14 and 15 are independently controlled to change the direction of the microcapsules, but the method of sequentially changing the potentials of the four electrodes in a rotary manner is also effective.

Another embodiment is a liquid crystal display device shown in FIG. In this liquid crystal display device, the internal liquid crystal 12
Besides, since the external liquid crystal 3 as a supporting member simultaneously contributes to the attitude control of the microcapsule 11, a higher speed and higher display quality can be obtained. Further, in this case, since the liquid crystal 3 is used as the supporting member of the microcapsule 11, the external liquid crystal 3 follows the regulation force of the alignment film 6 and acts to return to the initial state. Absent.

However, by incorporating a voltage holding element such as a TFT, a better display is possible.
Further, the present invention provides a conventional GH in a liquid crystal in which fine particles are dispersed.
It contains a dichroic dye used in LCDs. Not only the light absorption effect of both fine particles and dichroic dyes, but also the orientation field is disturbed by the fine particles, which makes it possible to efficiently absorb dichroic dyes that have only one absorption axis in all directions. .

The fine particles used in the present invention are movable in a fixed direction with respect to a fulcrum fixed to the substrate. If the liquid crystal is sandwiched between the substrates and the fine particles are simply dispersed in the liquid crystal, the fine particles may agglomerate, the in-plane density of the fine particles may be biased, or the fine particles may be adsorbed to the substrate interface to operate the fine particles. Sometimes you can't. Therefore, a part of the fine particles is movably fixed to a fulcrum fixed to the substrate,
It can operate well if it can be moved in a certain direction.

The method of manufacturing the liquid crystal display device of the present invention will be specifically described below. (Example 1) A scanning line, a signal line, and
A TFT switch element was provided, and a pixel electrode having a size of 200 μm was provided in a matrix at a position surrounded by the scanning line and the signal line by ITO. A transparent electrode made of ITO was provided on the entire surface of the other substrate, and a black matrix was provided at positions corresponding to the scanning lines and the signal lines.

Next, a solvent-soluble ring-closing polyimide was applied by spin coating to the surface of each of the substrates on which the transparent electrodes were formed, and post-baking was performed at 180 ° C. for 1 hour to fix the substrates. This polyimide film was rubbed to form a rubbing film.

Spherical polystyrene fine particles having a diameter of 0.5 μm formed by emulsion polymerization were used, and the opposite poles of the fine particles were dyed black with a dye to form fine particles 1 shown in FIG. As a method of dyeing opposite poles facing each other, first, by spraying fine particles on a colored substrate and pressing another colored substrate on the scattered colored substrate, it is possible to dye the opposite poles of the fine particles. it can.

In this embodiment, a dye having a surface tension different from that of the material forming the fine particles is used, and this dyed portion (colored area)
Has a surface tension smaller than that of the liquid crystal, and the surface tension of the unstained portion (non-colored region) is larger than that of the liquid crystal.

The fine particles thus obtained were added to Np liquid crystal in an amount of 1
By mixing 0 wt% and applying ultrasonic waves, they were uniformly dispersed in the liquid crystal. A cell is assembled by facing the two substrates that have been subjected to the rubbing treatment described above, and Np liquid crystal in which the fine particles are dispersed is injected into the cell to prepare a liquid crystal display device having an interelectrode distance of 6 μm (FIG. 9). , FIG. 10).

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown. .

(Embodiment 2) A scanning line, a signal line and a TFT switch element are provided on one side of two transparent substrates, and a 200 μm square pixel electrode is formed by ITO in a matrix at a position surrounded by the scanning line and the signal line. Set up in. A transparent electrode made of ITO was provided on the entire surface of the other substrate, and a black matrix was provided at positions corresponding to the scanning lines and the signal lines.

Next, a solvent-soluble ring-closing polyimide was applied by spin coating to the surface of each of the substrates on which the transparent electrodes were formed, and post-baking was performed at 180 ° C. for 1 hour to fix the substrates. This polyimide film was rubbed to form a rubbing film.

Black polyacrylic fine particles having a diameter of 1 μm formed by emulsion polymerization were impregnated in a PVA solution, and PVA was applied to the surface.
Thin film was formed. At this time, the direction in which the fine particles were pulled out from the solution was kept constant, and a PVA film strongly stretched in the pulling direction was formed on the surface of the fine particles. Thus, the liquid crystal molecules can be aligned on the surface of the fine particles.

Next, titanium oxide was vapor-deposited on a part of the surface of the fine particles so that the non-colored portions became white so that the black portions remained at the opposing electrodes, and the fine particles 1 shown in FIG. 1 were formed. . In this example, the surface tension of the dyed portion (colored area) was smaller than that of the liquid crystal, and the surface tension of the undyed portion (non-colored area, titanium oxide in this case) was larger than that of the liquid crystal.

The fine particles thus obtained were added to Np liquid crystal in an amount of 1
By mixing 0 wt% and applying ultrasonic waves, they were uniformly dispersed in the liquid crystal. The two substrates that have been subjected to the rubbing treatment are made to face each other to form a cell, and Np liquid crystal in which the fine particles are dispersed is injected into the cell, and the interelectrode distance is 15 μm.
A liquid crystal display device of No. 1 was produced (FIGS. 9 and 10).

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown. . In this embodiment, since the fine particle surface is subjected to the alignment treatment, the alignment direction on the fine particle surface can be aligned in one direction, and a more stable particle response can be obtained.

(Embodiment 3) A scanning line, a signal line and a TFT switch element are provided on one side of two transparent substrates, and a pixel electrode of 200 μm square is formed by ITO in a matrix at a position surrounded by the scanning line and the signal line. Set up in. A transparent electrode made of ITO was provided on the entire surface of the other substrate, and a black matrix was provided at positions corresponding to the scanning lines and the signal lines.

Next, a solvent-soluble ring-closing polyimide was applied by spin coating to the surface of each of the substrates on which the transparent electrodes were formed, and post-baking was performed at 180 ° C. for 1 hour to fix the substrates. In this example, a liquid crystal display device of a multi-domain system was prepared without subjecting the polyimide to an alignment treatment.

Both sides of an acrylic film in which a black dye having a thickness of 2 μm is dispersed are made white by depositing titanium oxide on both surfaces,
This was cut into a cube of 2 μm square to form fine particles shown in FIG. At this time, the direction of cutting out the fine particles was kept constant, and the surface of the fine particles was strongly stretched in the cutting direction. Thus, the liquid crystal molecules can be aligned on the surface of the fine particles.

In this embodiment, this dyed portion (colored area)
Has a surface tension smaller than that of the liquid crystal, and the surface tension of the unstained portion (non-colored region, in this case, titanium oxide) is larger than that of the liquid crystal.

The fine particles thus obtained were added to Np liquid crystal in an amount of 1
5 wt% was mixed and ultrasonic waves were applied to uniformly disperse the liquid crystal in the liquid crystal. The two substrates that have been subjected to the rubbing treatment are made to face each other to form a cell, and Np liquid crystal in which the fine particles are dispersed is injected into the cell, and the interelectrode distance is 15 μm.
A liquid crystal display device was prepared (FIG. 12).

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown. .

In this example, since the liquid crystal was injected in the isotropic liquid state without rubbing the polyimide film, the alignment of the liquid crystal was multi-domain (FIG. 12), and the orientation direction and the rising direction were in the display plane. The structure is not constant. Thus, a good display device having a particularly wide effective viewing angle can be obtained.

Example 4 A scanning line, a signal line and a TFT switch element were provided on one side of two transparent substrates, and a 200 μm square pixel electrode was provided with aluminum so as to cover the scanning line, the signal line and the switching element. . Further, a pigment dispersion type color filter in which 0.5% of titanium oxide of each of RGB colors is mixed is provided so as to cover the pixel electrode.

A transparent electrode is placed on this color filter.
A pixel pattern was formed with TO, and conduction was established with the aluminum electrode through a through hole. On the other substrate, a transparent electrode made of ITO and a yellow filter corresponding to a part of a blue pixel were formed on the entire surface, and a black matrix was formed at a position corresponding to the scanning line and the signal line.

Next, a solvent-soluble ring-closing polyimide was applied to both substrates by spin coating, and post-baking was performed at 180 ° C. for 1 hour to fix the substrates on the substrates. The 1 μm diameter transparent polystyrene fine particles formed by emulsion polymerization were subjected to vertical alignment treatment using a silane coupling agent. In this way, the liquid crystal molecules can be aligned perpendicularly to the surface of the fine particles.

Next, titanium oxide was vapor-deposited on both electrode portions of the fine particles to partially whiten them to obtain fine particles 1 shown in FIG. At this time, the white portion is a portion indicated by 2 and the other portions are transparent. 10% by weight of the fine particles thus obtained in Np liquid crystal
By mixing and applying ultrasonic waves, they were uniformly dispersed in the liquid crystal. A cell was assembled by facing the above-mentioned two rubbing-treated substrates, and Np liquid crystal in which the fine particles were dispersed was injected into the cell to prepare a liquid crystal display device having an interelectrode distance of 12 μm (FIG. 13). ). A color filter represented by 7 is a color filter having red, blue, and green. At this time, when a voltage is applied and the white part 2 shows up and down, light is scattered and shows white, and when the white part 2 faces sideways, the color of the underlying color filter is observed and color display is possible.

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown. .

(Embodiment 5) A scanning line, a signal line and a TFT switch element are provided on one side of two transparent substrates, and a 200 μm square pixel electrode is formed in a matrix in a position surrounded by the scanning line and the signal line by ITO. Set up in. A transparent electrode made of ITO was provided on the entire surface of the other substrate, and a black matrix was provided at positions corresponding to the scanning lines and the signal lines.

Next, a solvent-soluble ring-closing polyimide was applied by spin coating to the surface of each of the substrates on which the transparent electrodes were formed, and post-baking was performed at 180 ° C. for 1 hour to fix the substrates. This polyimide film was rubbed to form a rubbing film.

Spherical black polystyrene fine particles having a diameter of 0.2 μm formed by emulsion polymerization were crushed while applying heat to obtain disc-shaped fine particles 1 having a thickness of 0.07 μm shown in FIG.

The disc-shaped fine particles thus obtained were mixed in Np liquid crystal in an amount of 10 wt%, and ultrasonic waves were applied to uniformly disperse the fine particles in the liquid crystal. The above-mentioned two rubbing-treated substrates were made to face each other to form a cell, and Np liquid crystal in which the discotic fine particles were dispersed was injected into this cell to prepare a liquid crystal display device with an interelectrode distance of 6 μm ( (Fig. 11).

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was exhibited in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were exhibited. .

In the case of this embodiment, since the disc-shaped fine particles having a shape having anisotropy in one direction are used, it is possible to respond in the liquid crystal without giving a difference in surface tension to the surface. It has a feature.

(Embodiment 6) A scanning line, a signal line and a TFT switch element are provided on one side of two transparent substrates, and a 200 μm square pixel electrode is formed in a matrix in a position surrounded by the scanning line and the signal line by ITO. Set up in. A transparent electrode made of ITO was provided on the entire surface of the other substrate, and a black matrix was provided at positions corresponding to the scanning lines and the signal lines.

Next, a solvent-soluble ring-closing polyimide was applied by spin coating to the surface of each of the substrates on which the transparent electrodes were formed, and post-baking was performed at 180 ° C. for 1 hour to fix the substrates. This polyimide film was rubbed to form a rubbing film.

The black polyacrylic fine particles having a diameter of 1 μm formed by emulsion polymerization were crushed while applying heat to obtain disc-shaped fine particles 1 having a thickness of 0.5 μm shown in FIG. Further, after forming a thin film of PVA on the surface, it was pressed again to 0.4 μm. At this time, since the press machine was used in which grooves were formed in the same direction at a pitch of 0.1 μm on both sides, the surface of the fine particles was strongly stretched in the direction of the grooves when crushed. In this way, liquid crystal molecules can be aligned on the surface of the disc-shaped fine particles.

The fine particles thus obtained were added to Np liquid crystal in an amount of 1
By mixing 0 wt% and applying ultrasonic waves, they were uniformly dispersed in the liquid crystal. The two rubbing-treated substrates are made to face each other to form a cell, and the Np liquid crystal in which the discotic fine particles are dispersed is injected into the cell, and the interelectrode distance is set to 1
A 5 μm liquid crystal display device was prepared (FIG. 11).

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown. . In the present embodiment, by providing the disk-shaped fine particle surface with the orientation ability, the orientation direction on the fine particle surface can be aligned in one direction, and a more stable particle response can be obtained.

(Embodiment 7) A scanning line, a signal line, and a TFT switch element are provided on one side of two transparent substrates, and a 200 μm square pixel electrode is formed by ITO in a matrix at a position surrounded by the scanning line and the signal line. Set up in. A transparent electrode made of ITO was provided on the entire surface of the other substrate, and a black matrix was provided at positions corresponding to the scanning lines and the signal lines.

Next, a solvent-soluble ring-closing polyimide was applied by spin coating to the surface of each of the substrates on which the transparent electrodes were formed, and post-baking was performed at 180 ° C. for 1 hour to fix the substrates. This polyimide film was rubbed to form a rubbing film.

The surface of the graphite thin film particles was vertically aligned using a silane coupling agent. In this example, thin plate-like fine particles having a thickness of 0.1 μm were obtained (FIG. 5). The fine particles thus obtained were mixed in Np liquid crystal in an amount of 10 wt%, and ultrasonic waves were applied to uniformly disperse the fine particles in the liquid crystal. A cell was assembled by facing the two substrates subjected to the rubbing treatment described above, and Np liquid crystal in which the discotic fine particles were dispersed was injected into the cell to prepare a liquid crystal display device having an interelectrode distance of 23 μm.

When the two substrates 4 are opposed to each other to form a cell, the stretched polyimide film 8 having a thickness of 1 μm is stretched and rubbed in a rubbing direction so that the liquid crystal layer has a thickness of 4 layers every 5 μm. Were matched and overlapped. This state is shown in FIG.
Shown in

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown. .

In this embodiment, since the liquid crystal layer is divided into four layers using the polyimide film, the fine particles can be uniformly dispersed in the liquid crystal layer. Further, the thickness of the liquid crystal layer can be increased while the fine particles are uniformly dispersed, and the contrast can be improved.

(Embodiment 8) This will be described with reference to FIG. Two
A scanning line, a signal line, and a TFT switch element were provided on one of the transparent substrates 4 and 4 ′, and a 200 μm square pixel electrode was provided from aluminum so as to cover the scanning line, the signal line, and the switching element. Further, a pigment dispersion type color filter 7 in which 0.5% of titanium oxide of each of RGB colors is mixed is provided so as to cover the pixel electrode. The transparent electrode 5 was formed in a pixel pattern on the color filter 7 with ITO, and the through electrode was electrically connected to the aluminum electrode. Then, a photosensitive polyimide wall 9 having a height of 10 μm was formed between the pixels. A transparent electrode 5 made of ITO and a yellow filter (not shown) corresponding to a part of the blue pixel are formed on the entire surface of the other substrate 4 ', and the positions corresponding to the scanning lines and the signal lines are formed. A black matrix (not shown) was formed on the substrate.

Next, a solvent-soluble ring-closing polyimide is applied to both substrates 4 and 4'by spin coating, and then 180 ° C.
After the post-baking was performed for 1 hour to fix it on the substrate, an alignment treatment was performed by a rubbing treatment.

Next, fine particles of titanium oxide were dispersed in white polyacrylic fine particles having a diameter of 1 μm formed by emulsion polymerization, and the fine particles were crushed while being heated to 0.5 μm.
Disc-shaped fine particles 1 having a diameter of m were formed. Further impregnated with a PVA solution to form a PVA thin film on the surface, and then 0.4 again.
By pressing to μm, disc-shaped fine particles 1 shown in FIG. 5 were obtained.

At this time, 0.
Since the material having grooves formed at a pitch of 1 μm was used, the surface of the fine particles was strongly stretched in the direction of the grooves when crushed. In this way, liquid crystal molecules can be aligned on the disk surface.

1 part of the fine particles thus obtained was added to Np liquid crystal.
By mixing 0 wt% and applying ultrasonic waves, they were uniformly dispersed in the liquid crystal. A cell is assembled by facing the two rubbing-treated substrates 4, 4 ′, and Np liquid crystal in which the fine particles are dispersed is injected into the cell to form a liquid crystal display device with an interelectrode distance of 10 μm. did.

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown. .

In this embodiment, the shape of the fine particles has anisotropy, which allows the particles to respond to liquid crystal molecules. When the disk-shaped fine particles face the display surface side, black display is performed, and when the surface is substantially vertical to the display surface, the color of the underlying color filter is displayed.

(Ninth Embodiment) A description will be given with reference to FIG. Two
A scanning line, a signal line, and a TFT switch element were provided on one of the transparent substrates 4 and 4 ′, and a 200 μm square pixel electrode was provided from aluminum so as to cover the scanning line, the signal line, and the switching element. Further, a titanium oxide film was deposited by 500 angstrom so as to cover the pixel electrode. A transparent electrode 5 was formed in a pixel pattern on the titanium oxide film with ITO, and conduction was established with the aluminum electrode through a through hole. Then, a photosensitive polyimide wall 9 having a height of 10 μm was formed between the pixels. The other substrate 4 '
A transparent electrode 5 made of ITO was formed on the entire surface.

Next, a solvent-soluble ring-closing polyimide was applied to both substrates 4 and 4'by spin coating, and then 180 ° C.
After the post-baking was performed for 1 hour to fix it on the substrate, an alignment treatment was performed by a rubbing treatment.

Fine particles of titanium oxide were dispersed in fine particles of white polyacryl having a diameter of 1 μm formed by emulsion polymerization.
By crushing this while applying heat, the disk-shaped fine particles 1 having a diameter of 0.5 μm shown in FIG. 5 were formed. These disc-shaped particles are colored in three colors of RGB, and three types of disc-shaped particles (1
R, 1G, 1B) were prepared.

Each of the disc-shaped particles 1 was mixed in Np liquid crystal at 10 wt%, and ultrasonic waves were applied to uniformly disperse it in the liquid crystal. 2 subjected to the rubbing treatment described above
A cell was assembled with the substrates 4 and 4 ′ facing each other, and Np liquid crystal in which the fine particles were dispersed was injected into the cell to prepare a liquid crystal display device with an interelectrode distance of 10 μm. At this time, RGB fine particles were arranged for each pixel.

Fine particles of each pixel (1R, 1G,
As a method of disposing the liquid crystal in which 1B) is mixed, a bubble jet printing method or the like can be used. When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown.

In this embodiment, the shape of the fine particles has anisotropy, which allows the particles to respond to liquid crystal molecules. When the disk-shaped particles face the display surface side, each color (red, green, blue) is displayed, and when the surface is almost perpendicular to the display surface, the back color is displayed. . Further, as shown in FIGS. 17 and 18, the fine particles are not limited to the disk shape, and spherical particles, cylindrical shapes, and other shapes can be used.

(Embodiment 10) This embodiment uses the fine particles having a cylindrical shape in the embodiment 8, and will be described with reference to FIG. Two transparent substrates 4,
A scanning line, a signal line, and a TFT switch element were provided on one of the substrates 4 ′, and a 200 μm square pixel electrode was provided with aluminum so as to cover the scanning line, the signal line, and the switching element. Further, a pigment dispersion type color filter 7 in which 0.5% of titanium oxide of each of RGB colors is mixed is provided so as to cover the pixel electrode. The transparent electrode 5 was formed in a pixel pattern on the color filter 7 with ITO, and the through electrode was electrically connected to the aluminum electrode. Furthermore, a photosensitive polyimide wall 9 having a height of 10 μm was formed between the pixels. A transparent electrode 5 made of ITO and a yellow filter (not shown) corresponding to a part of a blue pixel are formed on the entire surface of the other substrate 4 ', and the position corresponding to the scanning line and the signal line is formed. A black matrix (not shown) was formed on the substrate.

Next, a solvent-soluble ring-closing polyimide was applied to both substrates 4 and 4'by spin coating, and then 180 ° C.
After that, post-baking was performed for 1 hour to fix it on the substrate. A 1 μm thread in which liquid crystal polyester titanium oxide fine particles were dispersed and prevented in a liquid crystal state was cut out into a 3 μm cylindrical shape to obtain a fine particle 1 shown in FIG.

The fine particles thus obtained were added to Np liquid crystal in an amount of 1
By mixing 0 wt% and applying ultrasonic waves, they were uniformly dispersed in the liquid crystal. The two rubbing-treated substrates are made to face each other to form a cell, Np liquid crystal in which the fine particles are dispersed is injected into the cell, and the interelectrode distance is 10 μm.
The liquid crystal display device of

When a voltage was applied between the electrodes of the liquid crystal display device thus obtained for black-and-white display, a good alignment state was shown in the initial state, high contrast, and good display characteristics with a wide effective viewing angle were shown. .

In this embodiment, the shape of the fine particles has anisotropy, which allows the fine particles to respond to liquid crystal molecules. When the cylindrical fine particles have their upper surface facing the display surface side, black display is performed, and when the surface is substantially vertical to the display surface, the color of the underlying color filter is displayed.

(Embodiment 11) In this embodiment, an axis is provided for fine particles and the axis is movable with respect to a fulcrum provided on the substrate.

As shown in FIG. 19, a scanning line, a signal line, and a TFT switch element are provided on one of the two transparent substrates 4, and a transparent pixel electrode 5 of 200 μm square is formed by ITO.
The wiring was provided in a matrix. A black matrix was provided on the other substrate so as to correspond to the transparent electrodes and the wiring.

Next, a polyimide wall 9 having a height of 10 microns and having a pitch of 20 microns was provided on both substrates along the wiring. This is a fulcrum that supports the particles. Next, after applying solvent-soluble ring-closing polyimide on both substrates, 180
After the post-baking at 1 ° C. for 1 hour to fix it on the substrate, a rubbing process was performed along the wall 9 to form the alignment film 6.

The fine particles were subjected to a rubbing treatment on both sides of a 1 micron black polyimide film and then die-cut into a shape as shown in FIG. The die-shaped plate-like particles 1 are fixed on a polyimide wall 9 as shown in FIG. 19, two alignment-treated substrates 4 are opposed to each other and combined in a parallel cell, and an Np liquid crystal 3 is sandwiched between the electrodes, and a liquid crystal having a distance between electrodes of 25 μm is sandwiched. A display cell was produced. This liquid crystal display cell exhibited a good alignment state in the initial state, high contrast, and good display with a wide effective viewing angle.

(Embodiment 12) This embodiment is similar to Embodiment 11 except that the fine particles have an elliptical disk shape. The configuration of the device is almost the same as that of FIG. 19, except that the fine particles 1 are elliptical.

On the transparent substrate 4 having the two transparent electrodes 5 formed thereon, polyimide walls 9 having a pitch of 30 microns and a height of 10 microns were provided. This is a fulcrum that supports the particles.
Next, after solvent-soluble ring-closure type polyimide was applied to both substrates, post-baking was performed at 180 ° C. for 1 hour to fix them on the substrates, and then rubbing treatment was performed along the wall 9 to form the alignment film 6.

The fine particles are 1 μm formed by emulsion polymerization.
Diameter black polyacrylic particles are crushed into a inertial disc shape with a thickness of 0.5 μm by applying heat and pressure.
It was dipped in the solution to form a PVA thin film on the surface, and then pressed again to 0.4 μm to form it. At this time, the press machine used had grooves formed on both sides of the ellipse at a pitch of 0.1 μm in the minor axis direction. Therefore, when crushed, the particle surface was strongly stretched in the groove direction.

The ellipsoidal fine particles were arranged on the wall 9 so that the major axis of the ellipse was perpendicular to the wall. Two alignment treated substrates are made to face each other and combined in a parallel cell, and Np
A liquid crystal display cell having a distance between electrodes of 35 μm was produced by sandwiching the liquid crystal 3. This liquid crystal display cell exhibited a good alignment state in the initial state, high contrast, and good display with a wide effective viewing angle.

(Embodiment 13) As shown in FIG. 19, a scanning line, a signal line and a TFT switch element are provided on one side of two transparent substrates 4, and a transparent pixel electrode 5 of 200 μm square is made of ITO with respect to the wiring. It was provided in a matrix. On the other substrate, a black matrix corresponding to the entire transparent electrode and wiring was provided.

Both substrates were then provided with 15 micron high polyimide walls 9 at 10 micron pitch. This is a fulcrum that supports the particles. Next, after solvent-soluble ring-closure type polyimide was applied to both substrates, post-baking was performed at 180 ° C. for 1 hour to fix them on the substrates, and then rubbing treatment was performed parallel to the walls to form an alignment film 6.

The fine particles are 10 μm formed by emulsion polymerization.
A polystyrene particle having a diameter of m was formed into a single particle film, and in this state, it was formed by dyeing black and white with a dye (FIG. 20). The surface tension of this dyed part was smaller than that of the liquid crystal, and the surface tension of the non-dyeing part was made larger than that of the liquid crystal. The particles were dropped into the wall uniformly in-plane. The two alignment-treated substrates were opposed to each other, combined with a parallel cell, and the Np liquid crystal 3 was sandwiched between them to prepare a liquid crystal display cell with an interelectrode distance of 30 μm.
This liquid crystal display cell exhibited a good alignment state in the initial state, high contrast, and good display with a wide effective viewing angle.

(Example 14) Two transparent substrates were provided with polyimide walls having a pitch of 10 microns and a height of 15 microns. Further, bearing grooves were formed on the upper part of the wall at intervals of 12 microns by embossing. After applying the solvent-soluble ring-closure type polyimide, post-baking was performed at 180 ° C. for 1 hour to fix the polyimide on the substrate. A hole was made at the center of 10 μm-diameter black polyacrylic particles formed by emulsion polymerization and passed through a 1-micron diameter shaft. The particles were dipped in a PVA solution to form a PVA thin film on the surface. At this time, the particle surface was strongly stretched in the pulling direction because the particle pulling direction from the solution was kept constant. The particles were used as a single particle film, and titanium oxide was vapor-deposited so that a part thereof was white. This vapor deposition part is
The surface tension was smaller than that of the liquid crystal, and the surface tension of the non-deposited portion was made larger than that of the liquid crystal. The axis of the particles was placed on the bearing portion, and the two alignment-treated substrates were opposed to each other and combined with the cell, and Np liquid crystal was sandwiched between them to prepare a liquid crystal display cell with an interelectrode distance of 30 μm. This liquid crystal display cell exhibited a good alignment state in the initial state, high contrast, and good display with a wide effective viewing angle.

Example 15 On one of two transparent substrates,
A TFT switch element is provided, and a 200 μm square aluminum pixel electrode is provided so as to cover the switch element and the wiring portion, and R is provided on the aluminum pixel electrode.
Each color of GB was provided as a pigment dispersion type color filter in which 0.5% of titanium oxide was mixed. Further, a transparent electrode was provided in a pixel pattern to establish electrical connection with the aluminum electrode below. Further, on the other substrate, a yellow filter was provided corresponding to the entire transparent electrode and a part of the blue pixel. Two transparent substrates were provided with 20 micron pitch, 15 micron high polyimide walls. Further, bearing grooves were formed on the upper wall at intervals of 22 microns by stamping. After the solvent-soluble ring-closing polyimide was applied, post-baking was performed at 180 ° C. for 1 hour to fix it on the substrate, and then the wall was rubbed perpendicularly. Rubbing both sides of the polyimide film in which titanium oxide fine particles with a thickness of 2 microns are dispersed in antiparallel, and then 200 microns by embossing
A 20 micron strip was cut out. A shaft was provided at a center position of 20 microns, and the shaft was provided on the bearing. Two alignment treated substrates are made to face each other and combined in a parallel cell,
A p-liquid crystal was sandwiched between the electrodes to prepare a liquid crystal display cell with a distance between electrodes of 30 μm. This liquid crystal display cell showed a good alignment state in the initial state, had a high contrast, and was able to perform a good full-color display with a wide effective viewing angle.

(Embodiment 16) T is attached to one of two transparent substrates.
An FT switch element is provided, a 200 μm square aluminum pixel electrode is provided so as to cover the switch element and the wiring portion, and the black PI layer 5 is provided.
00 nm was provided. Further, a transparent electrode was provided in a pixel pattern to establish electrical connection with the aluminum electrode below. Between these pixels,
The pillars were made of photosensitive polyimide with a height of 10 μm. A transparent electrode was provided on the other substrate, and a polyimide pillar was provided in the same manner. After solvent-soluble ring-closing polyimide was applied to two transparent substrates, post-baking was performed at 180 ° C. for 1 hour to fix the polyimide on the substrates and then rubbing treatment was performed. 5 μm
A PET film in which thick barium sulfate fine particles were dispersed was patterned as shown in FIG. 24, and both surfaces were subjected to rubbing treatment in antiparallel. Two alignment-treated substrates were opposed to each other so as to sandwich this film and combined in a parallel cell, and Np liquid crystal was injected to prepare a liquid crystal display cell with an interelectrode distance of 20 μm. This liquid crystal display cell showed a good alignment state in the initial state, had a high contrast, and was able to perform a good full-color display with a wide effective viewing angle.

(Embodiment 17) In this embodiment, microcapsules containing fine particles and liquid crystal inside are used.

As shown in FIG. 28, one of the two transparent substrates 4 is provided with a TFT switching element for controlling the potential of the electrode 15 and the reflective electrode 14 facing each other on the wall for one pixel and the reflective electrode 14. It was set up below. On the other substrate, a black matrix corresponding to the entire transparent electrode 14 and wiring was provided.

Next, 10 μm formed by In-Situ condensation polymerization
A liquid crystal microcapsule of m diameter was sandwiched between substrates provided with a black dye layer, and heat and voltage were applied. By slowly cooling and removing the substrate, microcapsules with colored electrodes were obtained.
The microcapsules were mixed in pure water in an amount of 10 wt% and uniformly dispersed.

Next, a liquid crystal display cell having a distance of 20 μm between electrodes was prepared by sandwiching the dispersion liquid in which the microcapsules were dispersed with the two substrates facing each other. Writing was performed in the vertical direction and the parallel direction on this liquid crystal display cell substrate every other field, and good display with high contrast and wide effective viewing angle was obtained.

(Embodiment 18) As shown in FIG. 29, a scanning line, a signal line, a TFT switch element is provided on one of the two transparent substrates 4, and a pixel electrode of 200 μm square formed of a transparent electrode is used as a wiring. On the other hand, they are arranged in a matrix. On the other substrate, a black matrix corresponding to the transparent electrodes and wirings was provided.

Next, solvent-soluble ring-closure type polyimide was applied to both substrates and post-baked at 180 ° C. for 1 hour to fix them on the substrates, followed by rubbing treatment to form an alignment film.
Next, the liquid crystal microcapsules having a diameter of 2 μm formed by In-Situ radical polymerization were crushed into a disk shape (FIG. 26) having a thickness of 0.5 μm by applying heat and pressure. On this disk, black polystyrene was interfacially polymerized to fix its shape. 10 wt% of Np liquid crystal was mixed and ultrasonic waves were applied to uniformly disperse the liquid crystal in the liquid crystal. A liquid crystal display cell having a distance between electrodes of 10 μm was produced by sandwiching Np liquid crystal in which disks were dispersed by combining the two alignment-treated substrates in parallel cells. This liquid crystal display cell showed a good alignment state in the initial state, had a high contrast, and could perform a good display with a wide effective viewing angle.

(Embodiment 19) As shown in FIG. 28, one of the two transparent substrates 4 has a TF for controlling the potential of the electrode 15 and the reflective electrode 14 facing each other on one wall of one pixel.
The T switch element was provided below the reflective electrode. On the other substrate, a black matrix corresponding to the transparent electrodes and wirings was provided.

Next, 10 μm formed by In-Situ condensation polymerization
The m-diameter liquid crystal microcapsules were crushed into a disk shape (FIG. 26) having a thickness of 0.5 μm by applying heat and pressure. At this time, since the press machine had grooves formed on both sides in the same direction at a pitch of 0.1 μm, the surface of the microcapsules was strongly stretched in the direction of the grooves when crushed.
On this disk, black polystyrene was interfacially polymerized to fix its shape. The microcapsules were mixed in Fluorinert at 10 wt% and uniformly dispersed. A liquid crystal display cell having a distance between electrodes of 20 μm was prepared by sandwiching the dispersion liquid in which the two substrates were opposed to each other and the capsules were dispersed. Writing was performed in the vertical direction and the parallel direction on this liquid crystal display cell substrate every other field, and good display with high contrast and wide effective viewing angle was obtained.

(Embodiment 20) As shown in FIG. 29, a scanning line, a signal line, and a TFT are provided on one of the two transparent substrates 4.
A switch element is provided to cover the switch element and the wiring part.
An aluminum pixel electrode having a size of 00 μm was provided, and a RGB color filter was provided as a pigment dispersion type color filter in which 0.5% of titanium oxide was mixed. Further, transparent electrodes were provided in a pixel pattern to establish electrical continuity with the aluminum electrodes below. In addition, a wall of photosensitive polyimide was provided between the pixels with a height of 10 μm. Further, a yellow filter was provided on the other substrate so as to correspond to the entire transparent electrode and a part of the blue pixel. After coating the solvent-soluble ring-closing polyimide on two transparent substrates, 180
After post-baking at 1 ° C. for 1 hour to fix it on the substrate, rubbing treatment was performed.

Next, the liquid crystal microcapsules having a diameter of 2 μm formed by emulsion polymerization were crushed into a disk shape (FIG. 26) having a thickness of 0.5 μm by applying heat and pressure. Further, it was pressed again to 0.4 μm. At this time, since the press machine had grooves formed on both sides in the same direction at a pitch of 0.1 μm, the surface of the microcapsules was strongly stretched in the direction of the grooves when crushed. White polystyrene was interfacially polymerized on this disk to fix its shape. This disk is N
It was mixed in p liquid crystal at 10 wt% and was uniformly dispersed in the liquid crystal by applying ultrasonic waves. The two orientation-treated substrates were opposed to each other and combined in parallel cells to disperse the disks.
A p-liquid crystal was sandwiched between the electrodes to prepare a liquid crystal display cell having a distance of 10 μm. This liquid crystal display cell showed a good alignment state in the initial state and had a high contrast and a good full-color display with a wide effective viewing angle.

(Embodiment 21) As shown in FIG. 29, a scanning line, a signal line and a TFT are provided on one of the two transparent substrates 4.
A switch element is provided to cover the switch element and the wiring part.
An aluminum pixel electrode having a size of 00 μm was provided, and a RGB color filter was provided as a pigment dispersion type color filter in which 0.5% of titanium oxide was mixed. Further, transparent electrodes were provided in a pixel pattern to establish electrical continuity with the aluminum electrodes below. In addition, a wall of photosensitive polyimide was provided between the pixels with a height of 10 μm. Further, a yellow filter was provided on the other substrate so as to correspond to the entire transparent electrode and a part of the blue pixel.

Next, solvent-soluble ring-closure type polyimide was applied to the two transparent substrates 4 and post-baked at 180 ° C. for 1 hour to fix them on the substrates. A thread having a diameter of 5 μm obtained by spinning a liquid crystalline polyester in a liquid crystal state was cut into a column of 20 μm. After interfacially polymerizing white polystyrene on the cylinder, the liquid crystalline polyester portion was removed by a solvent. Liquid crystalline polyester remained in an aligned state inside the remaining white polystyrene column (FIG. 27). This column was mixed in Np liquid crystal at 10 wt% and was uniformly dispersed in the liquid crystal by applying ultrasonic waves. A liquid crystal display cell having a distance between electrodes of 40 μm was produced by sandwiching Np liquid crystal in which two substrates were opposed to each other and columns were dispersed. At this time, since the liquid crystal was injected in the isotropic liquid state without performing the alignment treatment, the alignment of the liquid crystal was multi-domain and the alignment orientation and the rising direction were not constant. This liquid crystal display cell showed a good alignment state in the initial state and had a high contrast and a good full-color display with a wide effective viewing angle.

[0165]

The liquid crystal display device of the present invention is for displaying fine particles by coloring them and dispersing them in the liquid crystal to provide a new type of liquid crystal display device having a high contrast and a wide effective field of view. It becomes possible.

[Brief description of drawings]

FIG. 1 is an enlarged view of fine particles used in the present invention.

FIG. 2 is a diagram showing how liquid crystal molecules are aligned when the fine particles are dispersed in the liquid crystal molecules.

FIG. 3 is an enlarged view of fine particles used in the present invention.

FIG. 4 is a diagram showing how liquid crystal molecules are aligned when the fine particles are dispersed in the liquid crystal molecules.

FIG. 5 is an enlarged view of fine particles used in the present invention.

FIG. 6 is a diagram showing how liquid crystal molecules are aligned when the fine particles are dispersed in the liquid crystal molecules.

FIG. 7 is an enlarged view of fine particles used in the present invention.

FIG. 8 is a diagram showing how liquid crystal molecules are aligned when the fine particles are dispersed in the liquid crystal molecules.

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

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

FIG. 11 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 12 is a cross-sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 13 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 14 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 15 is a cross-sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 16 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 17 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 18 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 19 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 20 is an enlarged view of fine particles used in the present invention.

FIG. 21 is an enlarged view of fine particles used in the present invention.

FIG. 22 is an enlarged view of fine particles used in the present invention.

FIG. 23 is an enlarged view of fine particles used in the present invention.

FIG. 24 is a perspective view of a panel substrate of a liquid crystal display device according to an embodiment of the present invention.

FIG. 25 is an enlarged view of fine particles used in the present invention.

FIG. 26 is an enlarged view of fine particles used in the present invention.

FIG. 27 is an enlarged view of fine particles used in the present invention.

FIG. 28 is a sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 29 is a cross-sectional view of a liquid crystal display device according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Fine particles 2 ... Colored part 3 ... Liquid crystal molecule 4 ... Substrate 5 ... Electrode 6 ... Alignment film 7 ... Color filter 8 ... Stretched film 9 ... Wall 10 ... Axis 11 ... Microcapsule 12 ... Liquid crystal in microcapsule 13 ... Microcapsule Support member 14 ... Electrode 15 ... Electrode

Claims (14)

[Claims] 1. A substrate, a liquid crystal material disposed on the substrate, fine particles dispersed in the liquid crystal material, and liquid crystal driving means for changing the alignment direction of liquid crystal molecules in the liquid crystal material. A liquid crystal display device characterized in that the orientation of the fine particles is changed in response to a change in the arrangement of the liquid crystal molecules driven by the liquid crystal driving means. 2. The liquid crystal display device according to claim 1, wherein at least a part of the fine particles is colored or absorbs or scatters light having a specific wavelength. 3. The surface of the fine particles is divided into first and second regions having different surface tensions, the surface tension of the first region is γ1, the surface tension of the second region is γ2, and the liquid crystal material has a surface tension of γ2. The liquid crystal display device according to claim 1 or 2, wherein γ1>γLC> γ2, where γLC is the surface tension. 4. The liquid crystal display device according to claim 1, 2 or 3, wherein the liquid crystal molecules are uniformly aligned on the surfaces of the fine particles. 5. The liquid crystal display device according to claim 1, 2, 3, or 4, wherein the shape of the fine particles is spherical. 6. The shape of the fine particles has anisotropy, claim 1, claim 2, claim 3 or claim 4.
The described liquid crystal display device. 7. The liquid crystal display device according to claim 6, wherein the fine particles have a plate shape. 8. A substrate, an accommodating member disposed on the substrate and accommodating a liquid crystal material therein, a support member movably supporting the accommodating member, and liquid crystal molecules in the liquid crystal material in the accommodating member. A liquid crystal driving means for changing the arrangement direction of the liquid crystal display device, and the orientation of the containing member is changed in response to a change in the arrangement of the liquid crystal molecules driven by the liquid crystal driving means. apparatus. 9. The part of the housing member is colored or absorbs or scatters light of a specific wavelength.
The described liquid crystal display device. 10. The liquid crystal display device according to claim 8, wherein the supporting member is a liquid crystal material. 11. The liquid crystal display device according to claim 8, 9 or 10, wherein the shape of the housing member is anisotropic. 12. The liquid crystal driving means applies a voltage between a pair of electrodes formed substantially parallel to the surface of the substrate and a pair of electrodes provided substantially perpendicular to the surface of the substrate, thereby storing the housing. The direction of a member is controlled, Claim 8, Claim 9, Claim 10 or Claim 11 characterized by the above-mentioned.
The described liquid crystal display device. 13. The particle or the containing member is movable in a fixed direction with respect to a fulcrum fixed to the substrate, claim 1, claim 2, claim 3,
Claim 4, claim 5, claim 6, claim 8, claim 9,
The liquid crystal display device according to claim 10, 11 or 12. 14. A liquid crystal material in which the fine particles are dispersed, a liquid crystal material housed in the housing member, or a liquid crystal material used as the support member contains a dichroic dye. The liquid crystal display device according to claim 2, claim 3, claim 4, claim 5, claim 6, claim 8, claim 9, claim 11, claim 12, claim 12, or claim 13.