JPH11160691A - Liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high polymer dispersion liquid crystal display element excellent in contrast, and a threshold characteristic, having uniform display quality and a high specific resistance and an excellent charge holding characteristic, allowing a drive voltage to be reduced as a reflection type, and having a high reliability, and to provide a method of manufacturing this element easily and stably. SOLUTION: This liquid crystal display element is an element characterized in that liquid crystal 105 and high polymers 104 are aligned in the same direction when an electric field is not impressed, in a phase wherein the liquid crystal 105 and the high polymers 104 are dispersed from each other and phase- separated, and the manufacturing method is characterized in that after the high polymers 104 or high polymer precursors are mixed with the liquid crystal 105 when they are in a liquid phase, the liquid crystal 105 and the high polymers 104 or the high polymer precursors are aligned, and then, the high polymers 104 and the high polymer precursors are cured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer-dispersed liquid crystal display device in which a liquid crystal and a polymer are dispersed in each other and a method of manufacturing the same, and is applied to a computer display or a video projector.

[0002]

2. Description of the Related Art In recent years, with the introduction of computers into places of social life, the development of man-machine interfaces has been accelerated. Particularly in the field of computer displays, development is most urgently required, but the current situation still relies on twisted nematic liquid crystal display elements. Since this display element uses two polarizing plates, it has a drawback that the efficiency of use of incident light is low and the display is dark.

Therefore, recently, a polarizing plate is unnecessary, and a polymer-dispersed liquid crystal (polymer) utilizing a difference in refractive index between a liquid crystal and a polymer has recently been used.
Display elements of dispersed liquid crystal) have been developed. This polymer-dispersed liquid crystal display device is a display device in which a liquid crystal and a polymer are dispersed in each other, and these are phase-separated. The principle of operation is that when the refractive indices of the two are matched by application or removal of an electric field, a transparent state where light is transmitted,
If the refractive indices of the two are different, a white turbid state (translucent state) in which light is scattered is formed.

A conventional polymer-dispersed liquid crystal display device is shown in FIG.
8 (see US Pat. No. 3600060). This polymer-dispersed liquid crystal display element has a liquid crystal polymer composite layer sandwiched between two transparent substrates 01 and 08, and a transparent electrode 02, 07 are respectively formed. In the liquid crystal polymer composite layer, fine particles of the liquid crystal 05 are dispersed in the polymer 04, and the liquid crystal 05 and the polymer 04 are in a phase separated state. The liquid crystal 05 has a positive dielectric anisotropy, and is aligned in the direction of the electric field when an electric field is applied. When no electric field is applied, the liquid crystal 05 has a refractive index of ordinary light (about 1.5) because it is randomly oriented.
And 1.6, which is the average of the extraordinary refractive index (about 1.7). Since the polymer 04 is cured in a randomly oriented state, its refractive index is about 1.5. In the figure, arrows indicate that the orientation direction is disordered.

As described above, since the interface between the liquid crystal 05 and the polymer 04 has a difference in refractive index of about 0.1, when no electric field is applied, as shown in FIG. The light that has entered the liquid crystal polymer composite layer from above becomes a scattering state, and the device becomes a cloudy state (translucent state). However, not all of the incident light is scattered, but polarized light parallel to the alignment direction of the liquid crystal molecules is scattered.

[0006] Further, as shown in FIG.
When a power source is connected between 2,07 and an electric field is applied to the liquid crystal polymer composite layer in the vertical direction in the figure, the liquid crystal 05 is aligned in the direction of the electric field, and the refractive index in the direction of the electric field is about 1.5. Match or approximate the refractive index of molecule 04. Therefore, when an electric field is applied, light incident on the polymer liquid crystal mixed layer from the direction of the electric field passes without scattering, and the element is in a transparent state.

In the above description, the element becomes opaque when no electric field is applied, and becomes transparent when an electric field is applied. The reverse operation can be performed.

That is, if the refractive index of the liquid crystal matches or approximates the refractive index of the liquid crystal when no electric field is applied, the incident light passes through the liquid crystal polymer composite layer without being scattered,
Therefore, the element becomes transparent. When an electric field is applied, the liquid crystal is aligned in the direction of the electric field, so that the difference between the refractive index of the liquid crystal and the refractive index of the polymer in the direction of the electric field is increased. As a result, the element becomes cloudy.

Although the principle utilizing the difference in refraction between the liquid crystal and the polymer has been described here, there is also an example of a polymer dispersion type liquid crystal display element which becomes transparent and opaque according to a principle different from this principle. For example, in a liquid crystal polymer composite layer obtained by mixing a liquid crystal with a polymer such as methacrylic acid ester having a biphenyl skeleton side chain and irradiating ultraviolet rays, the phenomenon of white turbidity caused by applying an electric field is based on this principle. I can't explain.

Further, a polymer liquid crystal composite display element to which a dichroic dye is added has been developed (1990 Society for Inform).
ation Display International Symposium digest of te
chnology Papers, lecture number 12.1, May 1990). This polymer-dispersed liquid crystal display element is obtained by adding a dichroic dye to the liquid crystal in a liquid crystal polymer composite layer sandwiched between two transparent substrates. In this device, when no electric field is applied, the incident light is scattered because the liquid crystal and the polymer have a difference in the refractive index. Here, since the dichroic dye is randomly oriented like the liquid crystal, the color of the dye is observed by the scattered light. When an electric field is applied to the device, the liquid crystal containing the dye is aligned in the direction of the electric field. In the direction of the electric field, there is no difference in the refractive index at the interface between the liquid crystal and the polymer, and the device becomes transparent. In general, colored paper is placed as a background on the back surface of the element.

[0011]

However, in the conventional polymer-dispersed liquid crystal display device, the fine particles of the liquid crystal are dispersed in the polymer, and the polymer is randomly oriented. Even when matching the refractive index with that of the polymer, a sufficient transmission state was not obtained, and a completely transparent state was not obtained. Further, since the particle diameters of the liquid crystal are not uniform, the display quality is not uniform and the reliability is lacking. Furthermore, when no electric field was applied, the liquid crystal molecules were randomly oriented, so that the response of each liquid crystal molecule to the electric field was uneven, and the threshold characteristics of the transmittance characteristics of the entire device were not steep.

Further, since the difference between the refractive index of the polymer of 1.5 and the average refractive index of the liquid crystal of 1.6 is small, even when the refractive indices of the liquid crystal and the polymer are different, a sufficient scattering state is not obtained. It did not become opaque. If the thickness of the liquid crystal composite layer is increased in order to increase the degree of scattering, a problem arises in that the driving power is increased to several tens of volts.

Further, the conventional display element has a problem that the contrast cannot be obtained because the steepness of the threshold characteristic is low. For example, the number of scanning lines is limited to three in simple matrix driving, and active elements such as TFTs (thin (thin)
film transistor) element or MIM (metal inslatorm)
etal) element or the like.

In the case of a polymer liquid crystal display element to which a dichroic dye is added, the display is switched between the transparent state and the color of the dye by application or removal of an electric field. Further, when the content of the dye is increased, the display becomes dark and the driving voltage is increased.

The present invention has been made in view of the above-mentioned prior art, and a liquid crystal and a polymer are aligned in the same direction to provide a bright polymer-dispersed liquid crystal display element having excellent threshold characteristics and good contrast. It is intended to provide. It is another object of the present invention to provide a reflective polymer dispersed liquid crystal display element having a low driving voltage, good contrast, good visibility, and a large-capacity display using the display element. Is to do. Still another object of the present invention is to provide a polymer-dispersed liquid crystal display device having high specific resistance and excellent charge retention characteristics. Still another object of the present invention is to provide a manufacturing method capable of stably manufacturing such a polymer-dispersed liquid crystal display device by an easy method.

[0016]

In order to achieve the above object, a polymer-dispersed liquid crystal display device according to the present invention has a structure in which a liquid crystal and a polymer are dispersed in each other and the liquid crystal and the polymer are phase-separated. A liquid crystal polymer composite layer is formed, and when the electric field is applied to align the liquid crystal in the direction of the electric field, the polymer dispersion type liquid crystal display element is in a light scattering state. It is characterized by being oriented in a direction.

Here, the liquid crystal polymer composite layer is sandwiched between two substrates, and has a transparent electrode on the inner surface of the two substrates, or is formed on one substrate. The one substrate may have a transparent electrode on the surface, and a transparent electrode may be formed on the upper surface of the liquid crystal polymer composite layer. The liquid crystal has a positive dielectric anisotropy, and the liquid crystal and the polymer are oriented in a direction parallel to the substrate when no electric field is applied, or have a negative dielectric anisotropy, The liquid crystal and the polymer may be oriented in a direction perpendicular to the substrate when no electric field is applied.

The liquid crystal and the polymer of the liquid crystal phase or the polymer precursor to be polymerized into a polymer are aligned on at least one inner surface of the two substrates in an orientation parallel to the substrates. It is desirable that the liquid crystal and the liquid crystal and the polymer of the liquid crystal phase or the polymer precursor to be polymerized into a polymer be aligned in a direction perpendicular to the substrate. Further, one of the two substrates is subjected to an alignment treatment for aligning the polymer of the liquid crystal and the liquid crystal phase or a polymer precursor to be polymerized into a polymer in a direction parallel to the substrate, The other of the two substrates is preferably subjected to an alignment treatment for aligning the liquid crystal and the polymer of the liquid crystal phase or a polymer precursor constituting the polymer in a direction perpendicular to the substrate. Note that an alignment film may be formed as the alignment process.

Here, one of the two substrates is
An electrode serving also as a reflective layer may be provided on the inner surface, or a reflective layer may be added. Further, the one substrate may have an electrode serving also as a reflective layer, or a reflective layer may be added.

The liquid crystal may be a nematic liquid crystal containing a chiral component, or may contain a dichroic dye.

Further, the polymer may be a polymer containing a biphenyl side chain, an ultraviolet curable polymer, a thermosetting polymer,
It can be a thermoplastic polymer, a polymer liquid crystal,
The polymer may have a co-solvent with the liquid crystal and form a liquid crystal phase in a compatible state. Further, the polymer can be obtained by polymerizing at least two or more polymer precursors having a polymer portion and an aromatic ring portion.

At least one of the polymer precursors contains a fluorine atom on the aromatic ring or on a side chain attached to the aromatic ring, or contains naphthalene, phenyl or biphenyl on the aromatic ring and It may contain a derivative, and the polymer precursor may be polymerized and cured by ultraviolet rays. Further, a retardation plate is disposed between the liquid crystal polymer composite layer and the reflection layer, and the optical axis of the retardation plate forms an angle of 45 degrees with the alignment direction of the liquid crystal polymer composite layer. A quarter-wave plate may be used as the retardation plate. A transparent electrode may be deposited on the surface of the phase difference plate. The reflection layer may be deposited on the surface of the phase difference plate.

The two polymer-dispersed liquid crystal display elements may be overlapped so that the alignment directions of the liquid crystal and the polymer in the liquid crystal polymer composite layer are orthogonal to each other. Preferably, the direction is perpendicular to a plane including the normal line of the substrate and the optical axis of the incident light. Further, a polarizing plate and a reflecting plate may be arranged on the back surface of the substrate, or a phase correction plate, a dimming plate and a reflecting plate may be arranged on the back surface of the substrate.

The structure according to the method of manufacturing a polymer-dispersed liquid crystal display element of the present invention that achieves the above object is to dissolve and mix a liquid crystal and a thermoplastic polymer and mix the liquid crystal and the polymer in a liquid crystal phase. By aligning in the same direction and then cooling and curing the polymer, the liquid crystal and the polymer are phase-separated while maintaining the alignment state, or the liquid crystal and the polymer precursor are dissolved. And the liquid crystal and the polymer precursor are aligned in the same direction in the liquid crystal phase, and then mixed.
By polymerizing the polymer precursor and curing it as a polymer, the liquid crystal and the polymer are phase-separated while maintaining the alignment state. At this time, two substrates or one substrate can be used. It is desirable that at least one of these substrates is subjected to an alignment treatment.

Here, it is desirable to adjust the speed of phase separation under the condition that the polymer has a particle diameter of 0.1 to 10 μm at which light scattering is best.

Here, methacrylate or acrylate of biphenylmethanol or a derivative of these compounds can be used as the polymer precursor, and methacrylate or acrylate of naphthol or a derivative of these compounds can be used. It can be used. Further, a mixture of the ester and a methacrylate derivative or acrylate derivative of biphenol with the ester may be used as the polymer precursor.

[0027]

(Embodiment 1) FIG. 1 shows a polymer dispersed liquid crystal display device according to a first embodiment of the present invention. As shown in the figure, a liquid crystal polymer composite layer is sandwiched between two transparent substrates 101 and 108. In this liquid crystal polymer composite layer, particles of the polymer 104 are dispersed in the liquid crystal 105. It is in a state of phase separation. As the polymer 104, a polymer that is compatible with the liquid crystal 105 in a liquid crystal phase state and then phase-separates from the liquid crystal 105 when cured is used. Liquid crystal 1
As 05, one having a positive dielectric anisotropy oriented in the direction parallel to the electric field direction is used. Two substrates 101,
108 has transparent electrodes 102 and 107 on the inner surface, respectively, and further has alignment films 103 and 107 thereon.
106 are formed.

The alignment films 103 and 106 are made of two substrates 10
An alignment treatment is performed to align the liquid crystal 105 and the liquid crystal phase polymer 104 that are compatible and sealed between the substrates 101 and 108 in a direction parallel to the substrates 101 and 108. Polymer 10
Reference numeral 4 denotes a liquid crystal phase at the time of alignment, but since it is cured, it is fixed while maintaining its alignment state. For this reason, even if an electric field is applied after that,
The orientation direction does not align with the electric field direction. The liquid crystal 10
In No. 5, since the alignment state is not fixed, when an electric field is applied, the alignment becomes uniform in the direction of the electric field.

Therefore, when no electric field is applied,
The orientation direction of the polymer 104 and the liquid crystal 105 is
In this state, the elements are in a transparent state by making the refractive indices of the two coincide with each other.

When a power supply is connected between the transparent electrodes 102 and 107 and an electric field is applied to the liquid crystal polymer composite layer, the alignment direction of the liquid crystal 105 is aligned with the electric field direction. A light scattering state occurs due to a mismatch in refractive index between the molecule 104 and the interface, and the element becomes cloudy.

The polymer 104 may be a polymer obtained by sealing a liquid crystal phase polymer precursor between two substrates 101 and 108 and then polymerizing the liquid crystal phase polymer precursor. In the liquid crystal polymer composite layer of the present embodiment, the polymer 1
Although the particles of No. 04 are dispersed in the liquid crystal 105, conversely, the particles of the liquid crystal 105 may be dispersed in the polymer 105.

Next, a method for manufacturing the above-mentioned polymer dispersed liquid crystal display device will be described.

First, transparent electrodes 102 and 107 were formed on the surfaces of two transparent substrates 101 and 108 by a vapor deposition method. Further, 2% of JIB (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.) is used as a polyimide on the surfaces of the transparent electrodes 102 and 107.
The solution was spin-coated at 2000 rpm to form an alignment film 103,
106. Thereafter, the two substrates 101 and 108 on which the alignment films 103 and 106 were formed were fired at 150 ° C.
After the firing, the surfaces of the alignment films 103 and 106 were subjected to an alignment treatment. As the alignment treatment, the alignment films 103 and 10 are made of bleached cotton.
A rubbing treatment of rubbing the surface of No. 6 in one direction was performed. The rubbing direction was such that the rubbing directions when the two substrates 101 and 108 were combined were parallel.

The alignment films 103 and 106 of the two substrates 101 and 108 were fixed to face each other so that the gap was 10 μm. Hereinafter, this gap is referred to as a cell thickness. The gap was filled with a mixture of the polymer precursor and the liquid crystal which were compatible and mixed at a ratio of 1:10. Here, paraphenylphenol methacrylate was used as the polymer precursor, and PN001 (trade name, manufactured by Roddick) was used as the liquid crystal. Subsequently, the mixture of the polymer precursor and the liquid crystal was gradually cooled, and irradiated with ultraviolet rays at room temperature to polymerize and cure the polymer precursor, and to cause phase separation as the liquid crystal 105 and the polymer 104.

The principle of operation of the display device manufactured as described above will be described.

The polymer 104 and the liquid crystal 105 shown in FIG.
Similar refractive index anisotropy is exhibited, and the refractive index in the direction parallel to the orientation direction is about 1.5, and the refractive index in the direction perpendicular to the orientation direction is about 1.7.

Therefore, when no electric field is applied, since the liquid crystal 105 is oriented in the same direction as the polymer 104, the substrate 101,
Liquid crystal 105 and polymer 1 in a direction perpendicular to 108
04 have the same refractive index. Therefore, at this time,
It became almost transparent and the transmittance was 80%. In the conventional example where liquid crystals and polymers are randomly arranged, the transmittance is
Since it is about 60%, it is understood that the transmittance is considerably improved when the polymer and the liquid crystal are aligned as in the present embodiment.

On the other hand, when a power supply is connected between the electrodes 102 and 107 and an electric field is applied to the polymer liquid crystal composite layer, the alignment direction of the polymer
Only 05 is oriented in the direction of the electric field, that is, in the direction perpendicular to the substrates 101 and 108. For this reason, the substrates 101, 1
In the electric field direction perpendicular to 08, the refractive index of the polymer 104 remains about 1.7, whereas the refractive index of the liquid crystal 105 is about 1.5.

Therefore, the difference in the refractive index between the polymer 104 and the liquid crystal 105 in the direction of the electric field is about 0.2,
Light incident from a direction perpendicular to 1,108 will be scattered. Therefore, at this time, the element becomes cloudy in the direction of the electric field. When an AC electric field of 10 KHz and 10 V was applied between the two electrodes, due to the difference in the refractive index between the polymer and the liquid crystal,
It became cloudy. The contrast between the light transmitting state and the light scattering state was as good as 50: 1 or more.

In the above embodiment, the alignment film 10
Although polyimide was used as 3, 106, the present invention is not limited to this, and the liquid crystal 105 and the polymer 104 of the liquid crystal phase, that is, an alignment film having a power to align the liquid crystal in a physical sense. Can be widely used. The alignment treatment is not limited to the one using an alignment film, and is not limited to rubbing on a substrate. In addition, a magnetic or electrical treatment capable of aligning the liquid crystal in a physical sense is also used.

The liquid crystal 105 preferably has a refractive index anisotropy Δn as large as possible in order to improve the contrast. The content of the liquid crystal 105 is 50 to
97% is optimal. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. As long as the polymer 104 has a polymer main chain with a side chain having a benzene skeleton or a biphenyl skeleton, regardless of whether it is a thermoplastic polymer, a thermosetting polymer, or an ultraviolet-curing polymer, Can be widely used.

(Embodiment 2) This embodiment is an example in which thermoplastic α-methylstyrene is used as a polymer and polyvinyl alcohol is used as an alignment film. The basic structure of the element is the same as that of the first embodiment shown in FIG.

A method for manufacturing the polymer dispersed liquid crystal device will be described.

First, two substrates were spin-coated with a 2% aqueous solution of polyvinyl alcohol at 2000 rpm to form an alignment film, and further baked at 100 ° C. Next, the liquid crystal and the polymer are mixed at a ratio of 3: 1 and the mixture is heated at 150 ° C.
It was sealed between the two substrates described above. Α-
Methylstyrene (refractive index 1.61), liquid crystal is SS-5
008 (product number, Chisso Corporation, extraordinary light refractive index 1.60) was used. Subsequently, by cooling the mixture of the polymer and the liquid crystal, they were oriented, and the polymer was cured and the liquid crystal and the polymer were phase-separated.

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent when no voltage was applied, and a transmittance of 60% was obtained. In the conventional example in which no alignment treatment is performed, the transmittance is about 50%, so that it can be seen that this embodiment is considerably improved.

When an AC electric field of 10 KHz and 60 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer and the liquid crystal. The contrast is 1
A good value of 5: 1 or more was obtained.

In the above embodiment, polyvinyl alcohol is used as the alignment film. However, a material having a power of aligning liquid crystal, such as the above-mentioned polyimide, can be widely used. In order to improve the contrast, the liquid crystal preferably has a refractive index anisotropy Δn as large as possible, and more preferably, the liquid crystal whose extraordinary light refractive index is close to that of the polymer. The optimal content of the liquid crystal is 50 to 97% of the whole. If it is less than this, it will not respond to the electric field, and if it is more than this, it will not be possible to obtain contrast. Further, as the polymer, in addition to the thermoplastic polymer used in this embodiment, a thermosetting polymer, an ultraviolet curing polymer, or the like can be used in the same manner.

Further, a similar effect can be obtained by combining switching elements. Further, in the above embodiment, two substrates are used, but a liquid crystal polymer composite layer can be formed on one substrate. Further, it is not necessary to form the alignment film on both substrates, and it is effective to use only one substrate. Further, the alignment treatment is not limited to the one using the alignment film, and is not limited to rubbing the substrate. In addition, electrical or magnetic means for orienting the liquid crystal in a physical sense can be used.

The present invention can be applied not only to the above embodiments but also to computer displays, light control elements, light valves, light control mirrors and the like.

(Embodiment 3) FIG. 2 shows a polymer dispersed liquid crystal display device according to a third embodiment of the present invention. In this embodiment,
It uses a nematic liquid crystal containing a chiral component. That is, as shown in FIG.
1. A liquid crystal polymer composite layer is sandwiched between the substrates 308,
This liquid crystal polymer composite layer is in a state where the polymer 304 and the nematic liquid crystal 305 are twisted with each other and phase-separated. As the polymer 304, a polymer that is compatible with and dispersed in the nematic liquid crystal 305 in a liquid crystal phase state and then separates from the liquid crystal 305 when cured is used. As the nematic liquid crystal 305, a liquid crystal having a positive dielectric anisotropy oriented in a direction parallel to the electric field direction is used.

The nematic liquid crystal 305 contains a chiral component. Polymer 304 and nematic liquid crystal 30
It is considered that the reason why 5 was mutually twisted was that a chiral component was added. The two substrates 301 and 308 have transparent electrodes 302 and 307 on their inner surfaces, respectively.
The alignment films 303 and 306 are formed thereon. The alignment films 303 and 306 are composed of two substrates 301 and 3
In addition, an alignment process is performed to align the nematic liquid crystal 305 and the polymer 304 in the liquid crystal phase that are compatible and sealed between the substrates 301 and 308 in a direction parallel to the substrates 301 and 308.

The polymer 304 is in a liquid crystal phase when it is oriented, but is cured after that, so that the polymer 304 is fixed with its orientation maintained. For this reason, the orientation direction of the polymer 304 is not aligned with the direction of the electric field even when an electric field is subsequently applied. In addition, since the liquid crystal 305 has an unfixed alignment state, it is aligned in the direction of the electric field when an electric field is applied.

Therefore, when no electric field is applied,
The alignment direction of the polymer 304 and the nematic liquid crystal 305 coincides with the direction parallel to the substrates 301 and 308. In this state, by making the refractive indices coincide with each other, the element becomes a transparent state. If the chiral component is not mixed into the nematic liquid crystal 305, a plane on which the liquid crystal 305 can move out of the light vertically incident on the substrates 301 and 308, that is,
Since only polarized light having a vibration direction on a plane parallel to the sheet of FIG. 2 is modulated, the contrast cannot be sufficiently improved.

When the chiral component is mixed with the nematic liquid crystal 305 as in the present embodiment, the vibration direction of the light perpendicularly incident on the substrates 301 and 308 is changed to a direction other than parallel to the plane on which the liquid crystal 305 can move. Since the modulation is effectively applied to the polarized light having the above, the contrast can be sufficiently improved.

When a power source is connected between the transparent electrodes 302 and 307 and an electric field is applied to the liquid crystal polymer composite layer, the alignment direction of the liquid crystal 305 is aligned with the direction of the electric field. Due to the mismatch of the refractive index at the interface with the molecule 304, a light scattering state is caused, and this element is in a cloudy state.

Next, a method for manufacturing the above-mentioned polymer-dispersed liquid crystal display device will be described.

First, transparent electrodes 302 and 307 were formed on the surfaces of two transparent substrates 301 and 308 by vapor deposition. Furthermore, JIB is used as polyimide on the surface of the transparent electrode.
2000% of a 2% solution (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.)
The alignment films 303 and 306 were formed by spin coating at pm. After that, the two substrates 301 and 308 on which the alignment films 303 and 306 were formed were fired at 150 ° C. After the firing, the surfaces of the alignment films 303 and 306 were subjected to an alignment treatment. As the alignment treatment, a rubbing treatment was performed in which the surfaces of the alignment films 303 and 306 were rubbed in one direction with bleached cotton. The rubbing direction was such that the rubbing directions when the two substrates were combined were substantially parallel.

The surfaces of the alignment films of these two substrates were fixed to face each other with a gap of 10 μm. A polymer precursor and a nematic liquid crystal are mixed in the gap at a ratio of 1:10 at 100 ° C.
The mixture mixed in was sealed. As the polymer precursor,
Paraphenylphenol methacrylate was used, and LV-R2 (product number, manufactured by Roddick) was used as a nematic liquid crystal. The nematic liquid crystal was mixed with 1% of S-1011 (product number, manufactured by Merck) as a chiral component. Subsequently, the mixture of the polymer and the nematic liquid crystal was gradually cooled to align them. Thereafter, the polymer precursor was polymerized and cured by irradiating ultraviolet rays at room temperature, and the liquid crystal and the polymer were phase-separated.

The polymer-dispersed liquid crystal display device thus manufactured was almost transparent when no voltage was applied, and had a transmittance of 80% as shown in FIG.

Further, 10 KH is applied between the two electrodes 302 and 307.
When an AC electric field of z, 20 V was applied, a light scattering state was caused due to a difference in refractive index between the polymer 304 and the liquid crystal 305.
The transmittance in the light scattering state was 1% as shown in FIG. In the case where the chiral component is not added, the transmittance is about 40% as shown in FIG. 4, and it is understood that the transmittance is considerably improved in this embodiment.

Further, in this embodiment, since the chiral component was added to the liquid crystal, the threshold characteristic indicating the change in the amount of transmitted light with respect to the change in the voltage was remarkably improved, and a steepness β = 1.34 of the threshold characteristic was obtained. For this reason, in the simple matrix drive, the number of scanning lines could be 16 lines.

The alignment film is not limited to the polyimide used in the above embodiment, but may be a film capable of aligning liquid crystal such as polyvinyl alcohol. Also, the alignment treatment is effective for only one substrate. In the case where the surfaces of the two substrates are subjected to the orientation treatment, the respective orientation treatment directions are related to the content of the chiral component. Therefore, it is desirable to optimize each time. The liquid crystal preferably has a refractive index anisotropy Δn as large as possible in order to improve the contrast. The optimal content of the liquid crystal is 50 to 97% of the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained.

The chiral component to be mixed in the liquid crystal can be used even if it is not the one shown here. However, the turning ability that determines the pitch of the liquid crystal is important. That is, the pitch of the liquid crystal when the chiral component is mixed is P = 1/34.
Can be written as C. Where P is the pitch and the unit is μ
m and C are concentrations and the unit is%. The concentration is about 0.1% to 5%, which is 0.29 to 0.0059 μm in terms of pitch. Even when another chiral component is used, it is desirable that the pitch of the liquid crystal be within this range. Of course, there is no problem even if the chiral component is a multi-component system.

As long as the polymer has a side chain having a biphenyl skeleton on the polymer main chain, it does not matter whether it is a thermoplastic polymer, a thermosetting polymer, or an ultraviolet curing polymer. Can be widely used. A polymer having a skeleton similar to that of a liquid crystal molecule can be similarly used.

(Embodiment 4) This embodiment shows an example in which the reflection type is used in Embodiment 3. The basic configuration is the same as that of the third embodiment shown in FIG. However, Example 3
In this case, a metal material such as aluminum is used for the electrode 307 on one substrate 308 instead of the transparent conductive material. Therefore, light incident on the element is reflected by the electrode 307, which is a reflective layer, and passes back and forth through the polymer liquid crystal composite layer.

In this embodiment, since one electrode 307 also serves as a reflection layer, when the cell thickness is the same as that in Embodiment 3, the transmittance (reflectance) at the time of scattering can be halved, and the contrast is doubled. It became. In addition, half the cell thickness is sufficient to obtain the same contrast as in the third embodiment, so that there is an advantage that the driving voltage can be reduced to half. Specifically, when the cell thickness is 7 μm and the driving voltage is
It was able to be 7V.

In this embodiment, the electrode 307 also serves as a reflection layer. However, a reflection layer may be added in addition to the electrode 307.

Example 5 FIG. 5 shows a polymer-dispersed liquid crystal display device according to a fifth example of the present invention. In this embodiment,
This is a combination of MIM (metal insulator metal) elements, which are composite two-terminal elements. The MIM element is one of the active elements and has a non-linear resistance characteristic. The basic configuration is the same as that of the third embodiment.

A method for manufacturing this device will be described. The difference from the third embodiment is that an MIM element is formed on the substrate 508. That is, tantalum was deposited as an electrode 511 on the surface of the substrate 508, and the surface was oxidized to form an insulating layer 510.
Aluminum was deposited thereon as a pixel electrode 509 also serving as a reflective layer. Further, a polyimide was applied thereon as an alignment film 506, baked, and subjected to an alignment treatment. Rubbing treatment was combined with the orientation film 506 as the orientation treatment. The orientation treatment is not limited to this, and an oblique deposition method can be used. The substrate 508 on which the MIM element thus formed was formed, the substrate 501 on which the transparent electrode 502 and the alignment film 503 were formed were opposed to each other, fixed to a cell thickness of 7 μm, and the periphery was molded.

A mixture of the polymer precursor and the nematic liquid crystal at a ratio of 1:10 at 100 ° C. was sealed in the gap. Biphenol methacrylate was used as the polymer precursor, and LV-R2 (product number, manufactured by Roddick) was used as the nematic liquid crystal. 1% of a chiral component S-1011 (product number, manufactured by Merck) was added to the nematic liquid crystal. Subsequently, the mixture of the nematic liquid crystal and the polymer precursor was gradually cooled, and then irradiated with ultraviolet rays at room temperature to polymerize the polymer precursor and cure it as a polymer, and to phase-separate the liquid crystal and the polymer. Was.

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent in the state where no voltage was applied, and a reflectance of 75% was obtained.

When an AC electric field of 10 KHz and 7 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer 504 and the liquid crystal 505. The reflectance in the light scattering state was 1%. When the chiral component is not added, the transmittance is about 40%.
It can be seen that the transmittance is significantly improved.

In this embodiment, 400 scanning lines and 64 signal lines are used.
The trial production of 0 display bodies was performed, and uniform display was obtained on the entire screen. Thus, by forming a reflective layer on one of the substrates, it is possible to combine the reflective layer with an MIM element and to apply it to a large-capacity display.
Note that the alignment film is not limited to polyimide, and a wide range of materials having a power of aligning liquid crystal, such as polyvinyl alcohol, can be used. In addition, the alignment treatment is effective for only one substrate. When the surfaces of two substrates are subjected to the orientation treatment, the orientation directions of the two substrates are related to the content of the chiral component. Therefore, it is desirable to optimize each time.

The liquid crystal preferably has a refractive index anisotropy Δn as large as possible in order to improve the contrast. The use of substances having a structure of liquid crystal molecules and a structure of a polymer precursor similar to each other can improve the transmittance or the reflectance in the transmission state. The liquid crystal content is 50-97% of the whole
Is optimal. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The chiral component to be mixed in the liquid crystal can be used even if it is not the one shown here. However,
The turning ability that determines the pitch of the liquid crystal when mixed is important.

That is, the pitch of the liquid crystal when the chiral component is mixed can be expressed as P = 1 / 34C.
Here, P is the pitch and the unit is μm, and C is the concentration and the unit is%. The density is about 0.1% to 5%.
0.29 to 0.0059 μm. Even when another chiral component is used, it is desirable that the pitch of the liquid crystal be within this range. Of course, there is no problem even if the chiral component is a multi-component system.

As long as the polymer has a polymer main chain with a side chain having a biphenyl skeleton, it does not matter whether it is a thermoplastic polymer, a thermosetting polymer, or an ultraviolet-curing polymer. , Can be widely used. Alternatively, a polymer having a skeleton similar to a liquid crystal molecule can be used similarly.

In this embodiment, the electrode 509 also serves as a reflection film.
Is provided on the substrate 508 on which the MIM element is formed. However, the reflection layer may be formed on the electrode 502 of the substrate 501 facing the substrate 508, or the reflection layer may be laminated thereon.

Embodiment 6 FIG. 6 shows a polymer-dispersed liquid crystal display device according to a sixth embodiment of the present invention. In this embodiment,
This is a combination of a TFT (thin film transistor) element which is a three-terminal element. Example 3 for basic configuration
Is the same as The difference from the third embodiment is that the substrate 608 has TF
The point is that a T element is formed.

A method for manufacturing this device will be described. First, a gate electrode 617 is formed on the surface of the substrate 608,
A gate insulating layer 616 was provided thereover, and a semiconductor layer 615, a drain electrode 614, a source electrode 613, and a pixel electrode 609 also serving as a reflective layer were formed. An alignment film 606 was formed on the element substrate and subjected to an alignment process. Substrate 6
For 01, an electrode 602 was formed, an alignment film 603 was formed thereon, and an alignment process was performed. This alignment process
In addition to the method of rubbing the substrate, an oblique deposition LB film method or the like can be used. Next, these two substrates 601, 60
8 so that the orientation directions are substantially parallel,
The cell was fixed so as to have a cell thickness of 7 μm, and the periphery was molded.

The polymer precursor and the nematic liquid crystal were mixed at a ratio of 1:10 at 100 ° C. and sealed in the gap. Biphenol methacrylate was used as the polymer precursor, and LV-R2 (product number, manufactured by Roddick) was used as the nematic liquid crystal. To the nematic liquid crystal, 1% of S-1011 (product number, manufactured by Merck) was added as a chiral component. Subsequently, the mixture of the polymer precursor and the nematic liquid crystal was gradually cooled to align them.
Thereafter, the polymer precursor was polymerized by irradiating ultraviolet rays at room temperature to obtain a polymer, and the nematic liquid crystal and the polymer were subjected to phase separation.

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent under the condition that no voltage was applied, and a reflectance of 75% was obtained.

When an AC electric field of 10 KHz and 7 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer 604 and the liquid crystal 605. The transmittance in the light scattering state was 1%. When the chiral component is not added, the transmittance is about 40%. Therefore, it is understood that the transmittance is significantly improved in the present embodiment.

In this embodiment, the number of scanning lines is 400 and the number of signal lines is 64.
The trial production of 0 display bodies was performed, and uniform display was obtained on the entire screen. By forming the reflective layer in this way, it becomes possible to combine the TFT element with the TFT element, and it becomes possible to apply it to a large-capacity display.

The alignment film is not limited to polyimide, but may be any other material such as polyvinyl alcohol that can align liquid crystals in a physical sense. Also, the alignment treatment
It is effective to use only one substrate. In the case of performing the orientation treatment on the surfaces of the two substrates, it is necessary to optimize each time the orientation treatment direction is related to the content of the chiral component.

The liquid crystal preferably has a refractive index anisotropy Δn as large as possible in order to improve the contrast.
The liquid crystal may have a positive dielectric anisotropy. The use of substances having a structure of liquid crystal molecules and a structure of a polymer precursor similar to each other can improve the transmittance or the reflectance in the transmission state. The liquid crystal content is 50-97% of the whole
Is optimal. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained.

The chiral component to be mixed in the liquid crystal may be other than the one shown here. . However, the turning ability that determines the pitch of the liquid crystal is important. That is, the pitch of the liquid crystal when the chiral component is mixed is P = 1/3.
Can be written as 4C. Where P is the pitch and the unit is μ
m and C are concentrations and the unit is%. The concentration is about 0.1% to 5%, which is 0.29 to 0.0059 μm in terms of pitch. Even when other chiral components are used, the pitch of the liquid crystal needs to be within this range. Of course, there is no problem even if the chiral component is a multi-component system.

As the polymer, any polymer may be used as long as it is a polymer having a main chain with a side chain having a biphenyl skeleton, regardless of whether it is a thermoplastic polymer, a thermosetting polymer, or an ultraviolet-curing polymer. Can be widely used. Alternatively, a polymer having a skeleton similar to a liquid crystal molecule can be used similarly.

In the above embodiment, the reflection type is applied to the MIM element and the TFT element. However, if the driving voltage of the polymer dispersion type liquid crystal display element is reduced, the transmission type MIM element is used. Application to a TFT element can also be realized. Alternatively, even if the driving voltage of the polymer dispersion type liquid crystal display element is not reduced, if the breakdown voltage of the MIM element and the TFT element is improved, the transmission type can be combined with the MIM element and the TFT element as they are.

In the above embodiment, two substrates are used.
A liquid crystal polymer composite layer can be formed on one substrate. In addition, it is not necessary to form an alignment film on both substrates, and an effect is exhibited only by processing one substrate. Also, the cell thickness need not be the value shown here, and may be determined according to the application.

The present invention can be applied not only to the above embodiments but also to computer displays, light control elements, light valves, light control mirrors and the like.

(Embodiment 7) FIG. 7 shows a polymer dispersed liquid crystal display device according to a seventh embodiment of the present invention. In this embodiment, an epoxy resin is used as the thermosetting polymer. The basic configuration is the same as that of the third embodiment shown in FIG.

A method for manufacturing this device will be described. First, the electrodes 702, 7 are provided on the surfaces of the two substrates 701, 708.
07 was formed by an evaporation method. These electrodes 702, 7
A 2% solution of JIB (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.) as a polyimide was spin-coated at 2000 rpm on the surface of 07 to form alignment films 703 and 706. The substrates 701 and 708 on which the alignment films 703 and 706 are formed
It was baked at 0 ° C. Thereafter, the alignment films 703 and 706
Was subjected to an orientation treatment by rubbing the surface of the sample with cotton in one direction. As the alignment treatment, means for aligning the physical liquid crystal in parallel with the substrates 701 and 708, such as a rubbing method, a rubbing method without an alignment film, an oblique vapor deposition method, and an LB film method are used. The rubbing direction was such that the rubbing directions when the two substrates 701 and 708 were combined were substantially parallel.
The alignment films 703 and 70 of these two substrates 701 and 708
6 were fixed to face each other so that the cell thickness became 10 μm.

A mixture of an epoxy resin and a nematic liquid crystal at 1: 9 at 100 ° C. was sealed in the gap.
As the epoxy resin, YDF-170 (trade name, manufactured by Toto Kasei) was used, and a curing agent 121 (trade name, manufactured by Yuka Shell) was added. As the nematic liquid crystal, LV-R
2 (product number, manufactured by Roddick) and 1% S-1011 (product number, manufactured by Merck) as a chiral component
Was added. Subsequently, the mixture of the epoxy resin and the nematic liquid crystal is gradually cooled to orient them, and then left at room temperature for one day to cure the epoxy resin and phase-separate the liquid crystal 705 and the polymer 704. I let it. In FIG. 7, arrows indicate the alignment directions of the polymer 704 and the liquid crystal 705. The same applies to other drawings.

The polymer-dispersed liquid crystal display device manufactured in this manner is almost transparent when no voltage is applied as shown in FIG. 7A, and has a transmittance of 80 as shown in FIG. %. When an AC electric field of 10 KHz and 10 V was applied between the two electrodes 702 and 707 as shown in FIG. 7B, a light scattering state was caused due to a difference in refractive index between the polymer 704 and the liquid crystal 705. The transmittance in the light scattering state was 1% as shown in FIG. In the case where the chiral component is not added, the transmittance is about 40% as shown in FIG. 9, and it can be seen that the transmittance is considerably improved in this embodiment. Further, the threshold characteristic indicating the change in the amount of transmitted light when the voltage is changed is also significantly improved.

The alignment film is not limited to polyimide, but may be a film capable of aligning liquid crystal in a physical sense, such as polyvinyl alcohol. Also, the alignment treatment is effective for only one substrate. When the surfaces of two substrates are subjected to the orientation treatment, the orientation directions of the two substrates are related to the content of the chiral component. The liquid crystal preferably has a refractive index anisotropy Δn as large as possible to improve the contrast. Also,
A liquid crystal having a positive dielectric anisotropy can be used.

The optimal content of the liquid crystal is 50 to 97% of the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The chiral component to be mixed in the liquid crystal can be used even if it is not the one shown here. However, the turning ability that determines the pitch of the liquid crystal is important. That is, the pitch of the liquid crystal when the chiral component is mixed can be expressed as P = 1 / 34C. Where P is the pitch in μm, C
Is the concentration and the unit is%. The concentration is about 0.1% to 5%, which is 0.29 to 0.0059 μm in terms of pitch. Even when other chiral components are used, the pitch of the liquid crystal needs to be within this range. Of course, there is no problem even if the chiral component is a multi-component system.

As the polymer, any thermosetting polymer that can be aligned in a state mixed with a liquid crystal and cured and polymerized in that state can be used in the same manner. For example, 4,4'-n
-Propylbiphenyl-ω, ω'-diisocyanate and a biphenyl diol may be mixed and polymerized. Ideally, any polymer precursor having a skeleton similar to liquid crystal molecules can be used in the same manner.

(Embodiment 8) In this embodiment, a thermoplastic resin poly-α-methylstyrene is used as the thermoplastic polymer. The basic configuration is the same as that of the seventh embodiment shown in FIG.

A method for manufacturing this device will be described. First, electrodes were formed on the surfaces of two substrates by a vapor deposition method.
JIB (trade name,
A 2% solution of Nippon Synthetic Rubber Co., Ltd.) was spin-coated at 2000 rpm to form an alignment film.

These substrates were fired at 150 ° C. Thereafter, the surface of the alignment film was exposed and rubbed in one direction with cotton. As the alignment treatment, in addition to the rubbing treatment described here, any method capable of aligning the liquid crystal, such as an oblique evaporation method and an LB film method, can be used. The rubbing direction was such that the rubbing directions when the two substrates were combined were substantially parallel.

The two substrates were fixed such that the cell thickness was 10 μm with the surfaces of the alignment films facing each other. In this gap, thermoplastic resin poly-α-methylstyrene and liquid crystal
The mixture mixed in was sealed. RDP80 as liquid crystal
616 (product number, manufactured by Roddick) was used. Subsequently, the mixture of the thermoplastic resin poly-α-methylstyrene and the liquid crystal was gradually cooled to orient them, and the mixture was brought to room temperature to cause phase separation and to cure the thermoplastic resin poly-α-methylstyrene.

The thus-produced polymer dispersed liquid crystal display element had a transmittance of 20% when no voltage was applied, as shown in FIG.

When an AC electric field of 10 KHz and 6 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer and the liquid crystal. The transmittance in the light scattering state was 1% as shown in FIG. Although this property is not so good, further improvement of the property is expected if the structure of the thermoplastic resin is optimized. Specifically, a skeleton that is easily compatible with liquid crystal molecules, such as a biphenyl group introduced into a side chain or a main chain, may be introduced.

The alignment film is not limited to polyimide, but may be any material that can align liquid crystals in a physical sense, such as polyvinyl alcohol. Also, the alignment treatment
It is effective to use only one substrate. Also, chiral components,
For example, when S-1011 (product number, manufactured by Merck) was added, the effect of improving threshold characteristics and improving contrast was confirmed. When the surfaces of two substrates are subjected to the orientation treatment, the orientation directions of the two substrates are related to the content of the chiral component.

The liquid crystal preferably has a refractive index anisotropy Δn as large as possible to improve the contrast. The optimal content of the liquid crystal is 50 to 97% of the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The chiral component to be mixed in the liquid crystal may be added under the conditions described in the seventh embodiment. As the polymer, a thermoplastic polymer that is compatible with the liquid crystal at a temperature higher than the use temperature, and is further aligned so as to be compatible with the liquid crystal phase, and can be cooled and phase-separated into the polymer and the liquid crystal can be used in the same manner. it can.

Embodiment 9 In this embodiment, a side chain type polymer liquid crystal having a cyanobiphenol group is used as the polymer liquid crystal. The basic configuration is the same as that of the seventh embodiment shown in FIG.

A method for manufacturing the device will be described. First, electrodes 2 and 7 were formed on the surfaces of two substrates 1 and 8 by a vapor deposition method. A 2% solution of JIB (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.) as a polyimide was spin-coated on the surface of these substrates at 2000 rpm to form an alignment film. These substrates were fired at 150 ° C. Thereafter, the surface of the alignment film was exposed and rubbed in one direction with cotton. As the alignment treatment, in addition to the rubbing treatment described here, any method capable of aligning the liquid crystal, such as an oblique evaporation method and an LB film method, can be used. The rubbing direction was such that the rubbing directions when the two substrates were combined were substantially parallel. The surfaces of the alignment films of these two substrates were fixed to each other so that the cell thickness became 10 μm.

In this gap, a side-chain type polymer liquid crystal having a cyanobiphenol group shown in Chemical formula 1 and a nematic liquid crystal are placed.
The mixture mixed at ℃ was sealed. LV-R2 (product number, manufactured by Roddick) was used as the nematic liquid crystal, and 1% of S-1011 (product number, manufactured by Merck) was added as a chiral component.

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Subsequently, the mixture of the side chain type polymer liquid crystal and the nematic liquid crystal was gradually cooled to orient them, and the liquid crystal and the polymer liquid crystal were phase-separated at 70 ° C.

The thus-produced polymer-dispersed liquid crystal display element had a transmittance of 80% when no voltage was applied, as shown in FIG.

When an AC electric field of 10 KHz and 10 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer and the liquid crystal. The transmittance in the light scattering state was 1% as shown in FIG. This characteristic is different from the conventional example shown in FIG. 9 in which the chiral component is not added.
It has been greatly improved. The display is possible without the chiral component, but the characteristics are inferior.

The alignment film is not limited to polyimide, but may be any material that can physically align liquid crystal, such as polyvinyl alcohol. Also, the alignment treatment
It is effective to use only one substrate. When the surfaces of two substrates are subjected to the orientation treatment, the orientation directions of the two substrates are related to the content of the chiral component. As a liquid crystal, to improve the contrast,
It is preferable that the refractive index anisotropy Δn is as large as possible. The liquid crystal may have a positive dielectric anisotropy. The optimal content of the liquid crystal is 50 to 97% of the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained.

The chiral component to be mixed in the liquid crystal may be added under the conditions described in the seventh embodiment. As a polymer, if the liquid crystal is compatible with the liquid crystal at a temperature higher than the use temperature, it is oriented in the compatible liquid crystal phase, and if cooled, the polymer and the liquid crystal can be phase-separated at the use temperature, the side chain type. The same can be used regardless of the main chain type. For example, a polymer liquid crystal represented by Chemical formulas 2 to 9 can be used. Of course, the polymer shown here is only an example, and it is desirable to optimize the structure by combining it with a liquid crystal or the like. In this embodiment, when the compatibility between the liquid crystal and the polymer liquid crystal is poor, a cosolvent of the liquid crystal and the polymer liquid crystal can be used. In this case, it is preferable to use a polymer liquid crystal which becomes a liquid crystal phase when a co-solvent is mixed, and after the alignment, distill off the solvent and phase-separate the liquid crystal from the polymer liquid crystal.

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(Embodiment 10) This embodiment shows an example in which the reflection type is used in Embodiments 7, 8, and 9. The basic configuration is the same as that of the seventh embodiment shown in FIG. The only difference is that the electrode 707 formed on the substrate 708 in FIG. 7 is made of a metal material such as aluminum instead of the transparent conductive material.

In this embodiment, since the electrode 707 also serves as a reflection layer, when the cell thickness is the same as that of the embodiment 7, the transmittance (reflectance) at the time of scattering can be reduced by half. That is, the contrast was doubled. In order to obtain the same contrast as in the seventh embodiment, half the cell thickness is sufficient, so that there is an advantage that the driving voltage can be reduced to half. Specifically, the driving voltage was 5 V with a cell thickness of 5 μm.

Embodiment 11 FIG. 12 shows a polymer-dispersed liquid crystal display device according to an eleventh embodiment of the present invention. This embodiment combines a MIM element which is a composite two-terminal element. For the basic configuration, see Embodiment 7 shown in FIG.
Is the same as The only difference is that an MIM element is formed on the substrate 1108. That is, tantalum was deposited as an electrode 1111 on the surfaces of the two substrates 1108, and the surfaces were oxidized to form an insulating layer 1110. Aluminum was deposited thereon as a pixel electrode 1109. Further, an alignment film 11 is further formed thereon.
06, a polyimide was applied, baked, and subjected to an orientation treatment. For the alignment treatment, besides the method of combining the alignment film and the rubbing, an oblique evaporation method can also be used. Thus M
A substrate 1108 on which an IM element is formed, an alignment film 1103,
The substrate 1101 on which the electrode 1102 was formed was combined, fixed to a cell thickness of 7 μm, and the periphery was molded.

In this gap, a mixture of an epoxy resin and a nematic liquid crystal at a ratio of 1: 9 at 100 ° C. was sealed. As the epoxy resin, YDF-170 (trade name, manufactured by Toto Kasei) was used, and a curing agent 121 (trade name, manufactured by Yuka Shell) was added. As a nematic liquid crystal, L
Using V-R2 (product number, manufactured by Roddick) and S-1011 (product number, manufactured by Merck) as a chiral component
Was mixed by 1%. Subsequently, the mixture of the epoxy-based resin and the nematic liquid crystal was gradually cooled, and the mixture was oriented and left at room temperature for one day to cure the epoxy-based resin and to cause phase separation as the liquid crystal 1105 and the polymer 1104.

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent under the condition that no voltage was applied, and a reflectance of 75% was obtained.

When an AC electric field of 10 KHz and 7 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer 1104 and the liquid crystal 1105. The reflectance in the light scattering state was 1%. In this embodiment, the number of scanning lines is 4
We prototyped a display with 00 lines and 640 signal lines.
A uniform display was obtained on all screens. in this way,
By forming a reflective layer on one of the substrates, it was possible to combine with a MIM element, and application to a large-capacity display became possible.

The alignment film is not limited to polyimide, but a wide variety of materials such as polyvinyl alcohol that can align liquid crystals in a physical sense can be used. Also, the alignment treatment
It is effective to use only one substrate. When the surfaces of two substrates are subjected to the orientation treatment, the orientation directions of the two substrates are related to the content of the chiral component.

The liquid crystal preferably has a refractive index anisotropy Δn as large as possible to improve the contrast.
The use of substances having a structure of liquid crystal molecules and a structure of a polymer precursor similar to each other can improve the transmittance or the reflectance in the transmission state. The optimal content of the liquid crystal is 50 to 97% of the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained.

The chiral component to be mixed in the liquid crystal may be added under the conditions described in the seventh embodiment. As the polymer, the polymer shown in Examples 8 and 9 may be used.

In this embodiment, the electrode 110 serving also as a reflection film is used.
9 is provided on the substrate 1108 on which the MIM element is formed, and the electrode 110 of the substrate 1101 facing the substrate 1108 is provided.
2 or a reflective layer can be laminated thereon.

Embodiment 12 FIG. 13 shows a polymer dispersed liquid crystal display device according to a twelfth embodiment of the present invention. In the present embodiment, a TFT element which is a three-terminal element is combined. The basic configuration is the same as that of the ninth embodiment shown in FIG.

A method for manufacturing this device will be described. The difference from the ninth embodiment is that a TFT element is formed on a substrate 1208. That is, a gate electrode 1217 is formed on the surface of one substrate 1208, a gate insulating layer 1216 is provided thereover, and a semiconductor layer 1215 and a drain electrode 121
4. The source electrode 1213 and the pixel electrode 9 also serving as the reflection layer were formed. An alignment film 1206 was formed thereon and subjected to an alignment process. For the other substrate 1201, the electrode 120
2 and an alignment film 1203 was formed thereon to perform an alignment process. As the alignment treatment, besides rubbing the alignment film, an oblique deposition method can also be used. Next, these two substrates 1201 and 1208 were combined so that the orientation processing directions were substantially parallel, and fixed so that the cell thickness became 7 μm, and the periphery was molded.

A mixture of a side chain type polymer liquid crystal having a cyanobiphenol group and a nematic liquid crystal at 120 ° C. was sealed in the gap. As a nematic liquid crystal, LV-
Using R2 (product number, manufactured by Roddick), S-1011 (product number, manufactured by Merck) was used as one chiral component.
% Mixed. Subsequently, the mixture of the side-chain type polymer liquid crystal and the nematic liquid crystal was gradually cooled, and they were oriented to 70 ° C., and the phases were separated as the liquid crystal 1205 and the polymer liquid crystal 1204.

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent when no voltage was applied, and a reflectance of 75% was obtained.

When an AC electric field of 10 KHz and 7 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer 1204 and the liquid crystal 1205. The transmittance in the light scattering state was 1%.

In this embodiment, the number of scanning lines is 400 and the number of signal lines is 64.
The trial production of 0 display bodies was performed, and uniform display was obtained on the entire screen. By forming the reflective layer in this way, it becomes possible to combine the TFT element with the TFT element, and it becomes possible to apply it to a large-capacity display.

The alignment film is not limited to polyimide, but may be any one that can physically align liquid crystal, such as polyvinyl alcohol. Also, the alignment treatment
It is effective to use only one substrate. When the surfaces of two substrates are subjected to the orientation treatment, the orientation directions of the two substrates are related to the content of the chiral component. As the liquid crystal, a liquid crystal having a refractive index anisotropy Δn as large as possible is preferable in order to improve the contrast. The use of materials having a structure similar to that of a liquid crystal molecule and a structure of a polymer makes it possible to improve transmittance or reflectance in a transmission state.

The content of the liquid crystal is optimally 50 to 97% of the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The chiral component to be mixed in the liquid crystal may be added under the conditions described in the seventh embodiment. As the polymer, besides the polymer liquid crystal shown in Example 9, the polymer shown in Examples 7 and 8 can be used in the same manner.

In the above embodiment, the reflection type is applied to the MIM element and the TFT element. However, if the driving voltage of the polymer dispersion type liquid crystal display element is reduced, the transmission type MIM element is used. Application to a TFT element can also be realized. Alternatively, if the withstand voltage of the MIM element and the TFT element is improved,
It can be combined with a MIM element or a TFT element as it is of a transmission type.

Although two substrates are used in the above embodiment, a liquid crystal polymer composite layer can be formed on one substrate. In addition, it is not necessary to form an alignment film on both substrates, and an effect is exhibited only by processing one substrate. Also, the cell thickness need not be the value shown here, and may be determined according to the application.

Embodiment 13 FIG. 14 shows a polymer dispersed liquid crystal display device according to a thirteenth embodiment of the present invention. In this embodiment, a liquid crystal having negative dielectric anisotropy is used, and the liquid crystal and the polymer are vertically aligned with respect to the substrate. As shown in the figure, two transparent substrates 1301 and 130
A liquid crystal polymer composite layer is sandwiched between the layers 8, and the liquid crystal polymer composite layer is in a state where particles of the polymer 1304 are dispersed in the liquid crystal 1305 and phase-separated. Polymer 1304
As the liquid crystal, a material that is compatible with and dispersed in the liquid crystal 1305 in a liquid crystal phase and then phase-separates from the liquid crystal 1305 when cured is used. As the liquid crystal 1305, a liquid crystal having a negative dielectric anisotropy oriented in a direction perpendicular to the electric field direction is used.

The two substrates 1301 and 1308 have transparent electrodes 1302 and 1307 on the inner surface, respectively.
Furthermore, alignment films 1303 and 1306 are formed thereon. The alignment films 1303 and 1306 are provided with a liquid crystal 1305 and a liquid crystal phase polymer 1304 which are mixed and sealed between the two substrates 1301 and 1308, respectively.
An orientation process for orienting in a direction perpendicular to 1108 is performed. The polymer 1304 is in a liquid crystal phase when it is oriented, but is thereafter cured, so that the polymer 1304 is fixed with its orientation maintained. Therefore, the orientation direction of the polymer 1304 is not aligned with the direction of the electric field even when an electric field is subsequently applied. In addition, since the liquid crystal 1305 has no fixed alignment state, the liquid crystal 1305 is aligned in the direction of the electric field when an electric field is applied.

Therefore, when no electric field is applied,
The orientation direction of the polymer 1304 and the liquid crystal 1305 in the solution shown in FIG. 13A coincides with the direction perpendicular to the substrates 1301 and 1308. In this state, the refractive indices of the two are made to coincide with each other. The device becomes transparent.

Further, as shown in FIG.
When a power supply is connected between 302 and 1307 and an electric field is applied to the liquid crystal polymer composite layer, the alignment direction of the liquid crystal 1305 is aligned in the direction perpendicular to the electric field direction. At the interface, a light scattering state occurs due to a mismatch in the refractive index at the interface, and the element becomes a cloudy state.

The polymer 1304 may be obtained by encapsulating a liquid crystal phase polymer precursor between two substrates 1301 and 1308 and then polymerizing the liquid crystal phase polymer precursor. In the liquid crystal polymer composite layer of this embodiment, the particles of the polymer 1304 are dispersed in the liquid crystal 1305. On the contrary, the particles of the liquid crystal 1305 may be dispersed in the polymer 1305. good.

Next, a method of manufacturing this device will be described. First, electrode layers 1302 and 1307 were formed on the surfaces of two substrates 1301 and 1308 by an evaporation method.
These substrates 1301 and 1308 were immersed in a 2% solution of LP-8T (trade name, manufactured by Shin-Etsu Silicone) for 30 minutes, washed with water, and dried at 130 ° C. to form alignment films 1303 and 1306.
The alignment film 130 of these two substrates 1301 and 1308
3, 1306 were fixed to each other so that the cell thickness became 10 μm. A mixture of paraphenylphenol methacrylate and liquid crystal at a ratio of 1:10 at 100 ° C. was sealed in the gap. As the liquid crystal, RDN00
775 (product number, manufactured by Roddick) was used. Subsequently, the mixture of the paraphenylphenol methacrylate and the liquid crystal was gradually cooled, and the mixture was oriented and irradiated with ultraviolet rays at room temperature to cure the paraphenylphenol methacrylate and to form the liquid crystal 1305 and the polymer 1304. The phases were separated.

The operating principle of the display device manufactured as described above will be described. A polymer 1304 shown in FIG. 14,
The liquid crystal 1305 has a similar refractive index anisotropy, with a refractive index in the direction parallel to the alignment direction of about 1.5 and a refractive index in the direction perpendicular to the alignment direction of about 1.7.

Therefore, as shown in FIG. 14A, when no electric field is applied, the liquid crystal 1305 is oriented in the same direction as the polymer 1304, so that the liquid crystal 1305 and the polymer in a direction perpendicular to the substrates 1301 and 1308. The refractive index of 1304 is 1.
Matches 5. Therefore, at this time, the device was almost transparent, and the transmittance was 50%.

On the other hand, as shown in FIG.
When an electric field is applied to the polymer liquid crystal composite layer by connecting a power supply between the liquid crystal 2130 and the polymer liquid crystal 1304, the alignment direction of the polymer 1304 remains unchanged, whereas only the liquid crystal 1305 is perpendicular to the electric field direction, that is, It is oriented in a direction parallel to the substrates 1301 and 1308. Therefore, the substrates 1301 and 130
In the electric field direction perpendicular to 8, the refractive index of the polymer 1304 remains about 1.5, whereas the refractive index of the liquid crystal 1305 is about 1.7.

Therefore, the polymer 1304 in the electric field direction
The difference between the refractive index of the liquid crystal 1305 and that of the liquid crystal 1305 is about 0.2, and light incident from a direction perpendicular to the substrates 1301 and 1308 is scattered about twice as much as the conventional one. Therefore, at this time, the element becomes white and cloudy in the direction of the electric field. When an AC electric field of 10 KHz and 20 V was applied between the two electrodes, the transmittance was 5%.

Further, in the above embodiment, the rubbing treatment for aligning the liquid crystal polymer composite layer is unnecessary, and only the vertical alignment treatment is required. Therefore, there is an advantage that the process is simplified. In addition, since the liquid crystal is vertically aligned in the state where no voltage is applied, the life is prolonged with respect to ultraviolet rays.

Incidentally, the polymer is a material which exhibits a liquid crystal phase even when mixed with liquid crystal, and has a benzene skeleton, preferably a biphenyl skeleton, introduced into the polymer. Furthermore, it must be able to polymerize in the liquid crystal phase by irradiation with ultraviolet light. Also, even if the polymer does not have a benzene skeleton,
Any polymer can be used as long as it is a polymer that aligns with the liquid crystal.

(Embodiment 14) This embodiment is an example using a thermosetting polymer. The basic configuration is the same as that of the thirteenth embodiment shown in FIG.

A method for manufacturing this device will be described. First, electrodes were formed on the surfaces of two substrates by a vapor deposition method.
These substrates are LP-8T (trade name, manufactured by Shin-Etsu Silicon)
Immersed in a 2% solution for 30 minutes, washed with water and dried at 130 ° C. to form an alignment film. The two substrates were fixed so that the alignment film surfaces faced each other to have a cell thickness of 10 μm. In this gap, a mixture of an epoxy resin and liquid crystal mixed at a ratio of 1: 9 at 100 ° C. was sealed. YDF- as epoxy resin
170 (trade name, manufactured by Toto Kasei) and a curing agent 121
(Product number, manufactured by Yuka Shell) was added. As the liquid crystal, RDN007775 (product number, manufactured by Roddick) was used. Subsequently, the mixture of the epoxy-based resin and the liquid crystal was gradually cooled, and these were orientated and allowed to stand at room temperature for one day to cure the epoxy-based resin and phase-separate the liquid crystal and the polymer.

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent when no voltage was applied, and had a transmittance of 40%.

When an AC electric field of 10 KHz and 10 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer and the liquid crystal. The transmittance in the light scattering state is
10%.

The polymer is a polymer which, when mixed with liquid crystal, exhibits a liquid crystal phase and can be thermoset polymerized in the liquid crystal phase. A benzene skeleton, preferably a biphenyl skeleton, is introduced into the polymer skeleton. If this is the case, the affinity with the liquid crystal is improved, so that the alignment is facilitated, which is convenient. Even if the polymer does not have a benzene skeleton, any polymer can be used as long as it is aligned with the liquid crystal. For example, 4,
4'-n-propylbiphenyl-ω, ω'-diisocyanate and a biphenyl diol may be mixed and polymerized.

(Embodiment 15) This embodiment uses a thermoplastic polymer. The basic configuration is the same as that of the thirteenth embodiment shown in FIG.

A method for manufacturing this device will be described. First, electrodes were formed on the surfaces of two substrates by a vapor deposition method.
These substrates are LP-8T (trade name, manufactured by Shin-Etsu Silicon)
Immersed in a 2% solution for 30 minutes, washed with water, and dried at 130 ° C. to form an alignment film. The two substrates were fixed so that the alignment film surfaces faced each other to have a cell thickness of 10 μm. A mixture of the thermoplastic resin poly-α-methylstyrene and the liquid crystal at 100 ° C. was sealed in the gap. RDN007775 as the liquid crystal
(Product number, manufactured by Roddick) was used. Subsequently, the mixture of the thermoplastic resin poly-α-methylstyrene and the liquid crystal was gradually cooled, and these were oriented to room temperature.
The thermoplastic resin poly-α-methylstyrene was cured and phase-separated into liquid crystal and polymer.

The polymer-dispersed liquid crystal display device thus manufactured was almost transparent and had a transmittance of 50% when no voltage was applied.

When an AC electric field of 10 KHz and 6 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer and the liquid crystal. The transmittance in the light scattering state is
10%.

Although this characteristic is not so good, further improvement of the characteristic is expected if the structure of the thermoplastic resin is optimized. Specifically, a skeleton that is easily compatible with liquid crystal molecules, such as a biphenyl group introduced into a side chain or a main chain, may be introduced.

The polymer is a thermoplastic polymer which is compatible with the liquid crystal at a temperature higher than the use temperature, is further aligned in the compatible liquid crystal phase, and can be cooled to phase-separate the polymer and the liquid crystal. It can be used similarly.

(Embodiment 16) This embodiment uses a polymer liquid crystal. The basic configuration is the same as that of the thirteenth embodiment shown in FIG.

A method for manufacturing this device will be described. First, electrodes were formed on the surfaces of two substrates by a vapor deposition method.
These substrates are LP-8T (trade name, manufactured by Shin-Etsu Silicon)
Immersed in a 2% solution for 30 minutes, washed with water, and dried at 130 ° C. to form an alignment film. The two substrates were fixed so that the alignment film surfaces faced each other to have a cell thickness of 10 μm. The gap 1
A mixture of a side chain type polymer liquid crystal having a cyanobiphenol group shown in FIG. 0 and a liquid crystal at 120 ° C. was enclosed. As the liquid crystal, RDN007775 (product number, manufactured by Roddick) was used. Subsequently, the mixture of the side-chain type polymer liquid crystal and the liquid crystal was gradually cooled to align them, and the temperature was set to 70 ° C. to cause phase separation between the liquid crystal and the polymer liquid crystal.

[0168]

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The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent when no voltage was applied, and had a transmittance of 80%.

When an AC electric field of 10 KHz and 10 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer and the liquid crystal. The transmittance in the light scattering state is
10%. In addition, as a polymer, if the liquid crystal is compatible with the liquid crystal at a temperature higher than the use temperature, it is further aligned in the compatible liquid crystal phase, and if cooled, the polymer and the liquid crystal can be phase-separated at the use temperature. The same can be used regardless of the chain type main chain type. For example, a polymer liquid crystal represented by Chemical Formulas 11 to 18 can be used. Of course, the polymer shown here is only an example, and it is desirable to optimize the structure by combining it with a liquid crystal or the like.

In this embodiment, when the compatibility between the liquid crystal and the polymer liquid crystal is poor, a cosolvent of the liquid crystal and the polymer liquid crystal can be used. In this case, it is preferable to use a polymer liquid crystal which becomes a liquid crystal phase when a co-solvent is mixed, and after the alignment, distill off the solvent and phase-separate the liquid crystal and the polymer liquid crystal.

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[0178]

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[0179]

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(Embodiment 17) This embodiment relates to Embodiment 13
It is a reflection type in Examples 14, 15, and 16. The basic configuration is the same as that of the thirteenth embodiment shown in FIG. However, in FIG.
The electrode 1307 formed thereon is made of a transparent conductive material and made of a metal material such as aluminum.

In this embodiment, since the electrode 1307 also serves as the reflection layer, when the cell thickness is the same as that in Embodiment 13, the transmittance (reflectance) at the time of scattering can be reduced by half. That is, the contrast was doubled. In order to obtain the same contrast as in the thirteenth embodiment, half the cell thickness is sufficient, so that there is an advantage that the driving voltage can be reduced to half. Specifically, with a cell thickness of 5 μm and a driving voltage of 5 V
And could be.

(Embodiment 18) FIG. 15 shows a polymer dispersed liquid crystal display device according to an eighteenth embodiment of the present invention. This embodiment combines a MIM element which is a composite two-terminal element. The basic configuration is the same as that of the thirteenth embodiment shown in FIG. However, an MIM element is formed on one substrate 1808.

A method for manufacturing this device will be described. First, tantalum was deposited as an electrode 1811 on the surface of one substrate 1808, and the surface was oxidized to form an insulating layer 1810. Aluminum was deposited thereon as a pixel electrode 1809. The substrate on which the MIM element is formed and the substrate 1801 on which the electrode 1802 is formed are connected to LP-8T
(Trade name, manufactured by Shin-Etsu Silicon) was immersed in a 2% solution for 30 minutes, washed with water, and dried at 130 ° C. to form alignment films 1803 and 1806. The alignment film 18 of these two substrates 1801 and 1808
03,1806 were fixed to face each other so as to have a cell thickness of 7 μm.

In this gap, a mixture of paraphenylphenol methacrylate and liquid crystal mixed at 1:10 at 100 ° C. was sealed. As the liquid crystal, RDN007775 (product number, manufactured by Roddick) was used. Subsequently, the mixture of the paraphenylphenol methacrylate and the liquid crystal is gradually cooled, and the mixture is oriented, and irradiated with ultraviolet rays at room temperature, whereby the paraphenylphenol methacrylate is cured, and the liquid crystal 1805 and the polymer 180 are cured.
And 4 were phase separated.

The polymer-dispersed liquid crystal display device manufactured in this manner was almost transparent under the condition that no voltage was applied, and a reflectance of 50% was obtained.

When an AC electric field of 10 KHz and 7 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer 1104 and the liquid crystal 1105. In the light scattering state, the reflectance was 5%. In this embodiment, the number of scanning lines is 4
We prototyped a display with 00 lines and 640 signal lines.
A uniform display was obtained on all screens. in this way,
By forming a reflective layer on one of the substrates, it was possible to combine with a MIM element, and application to a large-capacity display became possible.

As the polymer, the polymers shown in Examples 14, 15 and 16 may be used. In this embodiment, the electrode 1809 also serving as a reflection film is provided on the substrate 1808 on which the MIM element is formed. However, the reflection layer may be provided on the electrode 1802 of the substrate 1801 facing the substrate 1808, or the reflection layer may be provided thereon. Can be laminated.
(Embodiment 19) FIG. 16 shows a polymer dispersed liquid crystal display device according to a nineteenth embodiment of the present invention. In the present embodiment, a TFT element which is a three-terminal element is combined. The basic configuration is the same as that of the embodiment 16 shown in FIG. The only difference is that a TFT element is formed on a substrate 1908.

A method for manufacturing this device will be described. First, a gate electrode 1917 was formed over the surface of one substrate 1908, a gate insulating layer 1916 was provided thereover, and a semiconductor layer 1915, a drain electrode 1914, a source electrode 1913, and a pixel electrode 1909 also serving as a reflective layer were formed. An alignment film 1906 was formed on the substrate 1908 on which the TFT element was formed as described above. On the other substrate 1901, an electrode 1902 is formed, and an orientation film 19
03 was formed. This orientation treatment is the same as in the thirteenth embodiment. Next, these substrates 1901 and 1908 were combined, fixed so as to have a cell thickness of 7 μm, and molded around.

In this gap, a mixture of a side chain type polymer liquid crystal having a cyanobiphenol group and a liquid crystal at 120 ° C. was sealed. As the liquid crystal, RD00775 (product number,
Roddick). Subsequently, the mixture of the side-chain type polymer liquid crystal and the liquid crystal is gradually cooled, and these are oriented.
The liquid crystal and the polymer liquid crystal were phase-separated.

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent under no voltage application, and a reflectance of 50% was obtained.

When an AC electric field of 10 KHz and 7 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer 1904 and the liquid crystal 1905. In the light scattering state, the reflectance was 5%. In this embodiment, the number of scanning lines is 4
We prototyped a display with 00 lines and 640 signal lines.
A uniform display was obtained on all screens. in this way,
By forming a reflective layer on one of the substrates, it became possible to combine with a TFT element, and application to a large-capacity display became possible.

As the polymer, besides the polymer liquid crystal shown in Example 16, the polymers shown in Examples 13, 14 and 15 can be used in the same manner. In the above embodiment, the reflection type is applied to the MIM element and the TFT element. However, if the driving voltage of the display element portion is reduced, the transmission type MIM element and the TFT are used.
Application to elements can also be realized. Alternatively, a MIM element, T
If the breakdown voltage of the FT element improves, M
It can be combined with an IM element and a TFT element.

In Examples 13 to 19, two substrates were used. However, a liquid crystal polymer composite layer can be formed on one substrate. Also, the cell thickness need not be the value shown here, and may be determined according to the application. The alignment film used is not limited to LP-8T (trade name, manufactured by Shin-Etsu Silicon).
Materials that vertically align liquid crystals, such as MOAP and stearic acid, can be widely used. In addition, the alignment treatment is effective for only one substrate. As the liquid crystal, a liquid crystal having a negative dielectric anisotropy can be used. Further, the birefringence Δn of the liquid crystal is preferably as large as possible.

The content of the liquid crystal is optimally 50 to 97% based on the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. Dichroic dye in liquid crystal, for example, S-314
(Product number, manufactured by Mitsui Toatsu Chemicals), the color of the dye is scattered by the application of an electric field, and becomes transparent by the removal of the electric field. Regarding the refractive index of the polymer, it is preferable that the polymer has birefringence and the ordinary light refractive index is the same as the ordinary light refractive index of the liquid crystal.

The present invention can be applied not only to the above embodiments but also to computer displays, light control elements, light valves, light control mirrors and the like.

(Embodiment 20) FIG. 18 shows a polymer dispersed liquid crystal display device according to a twentieth embodiment of the present invention. In this example, a photopolymerizable precursor was used as a polymer precursor. FIG. 17 shows a conceptual diagram of the manufacturing apparatus.

A method of manufacturing this device will be described. First, the electrodes 200 are placed on the surfaces of the two substrates 2001 and 2008.
2,2007 was formed by an evaporation method. These electrodes 2
On the surface of 002 and 2007, a 2% solution of JIB (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.) was used as a polyimide at 2000 rpm.
And spin-coated to obtain alignment films 2003 and 2006. These alignment films 2003 and 2006 were fired at 150 ° C. Thereafter, the surfaces of the alignment films 2003 and 2006 were exposed and rubbed in one direction with cotton. The rubbing direction was such that the rubbing directions when the two substrates were combined were substantially parallel. Alignment film 2 of these two substrates 2001 and 2008
003 and 2006 were fixed so that the cell thickness became 10 μm.

In this gap, a mixture of paraphenylphenol methacrylate and nematic liquid crystal mixed at 1:10 at 100 ° C. was sealed. As a nematic liquid crystal,
Using LV-R2 (product number, manufactured by Roddick), 1% of S-1011 (product number, manufactured by Merck) was mixed as a chiral component. Subsequently, the mixture of the paraphenylphenol methacrylate and the nematic liquid crystal was gradually cooled to orient them, and was irradiated with ultraviolet rays at room temperature by an ultraviolet irradiation apparatus 2009 as shown in FIG. As a result, the paraphenylphenol methacrylate was cured, and the polymer 2004 and the liquid crystal 2005 were phase-separated.

In the ultraviolet irradiation device 2009, a 4 W ultraviolet fluorescent lamp (GL manufactured by NEC) was used as an ultraviolet irradiation lamp.
-4 sterilizing lamp), and the display element was irradiated with ultraviolet rays for 20 minutes at a position 1 cm away from the lamp. This ultraviolet fluorescent lamp has an emission intensity peak at 254 nm, and the irradiation amount is 5 mW / cm ² . Also, when the irradiation amount of the lamp is increased, the particle size of the generated polymer becomes small, and the scattering intensity cannot be obtained. In addition, when the particle size of the polymer is reduced, the structure is such that the polymer particles float in the liquid crystal, and the polymer particles that are supposed to be aligned and polymerized and fixed are not fixed. I can't.

Therefore, the irradiation amount of the ultraviolet irradiation lamp is
It is preferably 50 mW / cm ² or less, more preferably 10 mW / cm ² or less. That is, it is preferable that the polymerization is carried out slowly at a low luminescence intensity over a long period of time. If the above conditions are satisfied, other lamps can be used instead of fluorescent lamps for photopolymerization.

FIG. 19 shows an electron micrograph of a cross section of the device thus manufactured. From FIG. 19, it can be seen that the generated polymer particles are arranged along the orientation direction.

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent when no voltage was applied, and a transmittance of 80% was obtained.

When an AC electric field of 10 KHz and 20 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer and the liquid crystal. At this time, the transmittance was 1%. Further, as shown in FIG. 20, the threshold characteristic in the change of the transmitted light with respect to the applied voltage became steep, and as a result, 16 scanning lines could be scanned by the time division driving method.

As the polymer, it can be widely used as long as the precursor contains a skeleton similar to a liquid crystal skeleton such as a biphenyl skeleton. Further, the structure of the polymerization active portion is not limited to an ethylene skeleton as long as it can be polymerized by ultraviolet rays. For example, an epoxy polymer precursor can be used. This embodiment can also be applied to a case where a vertical alignment process is performed on a substrate. (Example 21) In this example, a thermopolymerizable precursor was used as a polymer precursor. The basic configuration is the same as that of the embodiment 20 shown in FIG.

A method for manufacturing this device will be described. First, electrode layers were formed on the surfaces of two substrates by a vapor deposition method. SP-740 as polyimide on the surface of these substrates
A 2% solution (trade name, manufactured by Toray Industries, Inc.) was spin-coated at 2000 rpm to form an alignment film. These substrates were fired at 250 ° C. Thereafter, the surface of the alignment film was exposed and rubbed in one direction with cotton. The rubbing direction was such that the rubbing directions when the two substrates were combined were substantially parallel. The surfaces of the alignment films of these two substrates were fixed to each other so that the cell thickness became 10 μm.

The gap was filled with a mixture of an epoxy resin and a nematic liquid crystal at a ratio of 1: 9 at 100 ° C.
As the epoxy resin, YDF-170 (trade name, manufactured by Toto Kasei) was used, and a curing agent 121 (trade name, manufactured by Yuka Shell) was added. As the nematic liquid crystal, LV-R
2 (product number, manufactured by Roddick) and 1% S-1011 (product number, manufactured by Merck) as a chiral component
Mixed. Subsequently, the mixture of the epoxy resin and the nematic liquid crystal was gradually cooled, and the mixture was oriented. The mixture was allowed to stand at 50 ° C. for 2 hours using a temperature controller (see FIG. 17) to cure the epoxy resin and at the same time to form a liquid crystal. The molecules were allowed to phase separate. The shape of the polymer particles thus formed was similar to FIG. Since the thermosetting conditions vary depending on the polymer precursor used, it is desirable to adjust the temperature and the curing time each time. The point is to determine the curing temperature so as to obtain the structure shown in FIG.

The polymer can be widely used as long as the precursor contains a skeleton similar to a liquid crystal skeleton such as a biphenyl skeleton. The structure of the polymerization active portion is not limited to an epoxy skeleton as long as it can be thermally polymerized.

(Embodiment 22) In this embodiment, a thermoplastic polymer is used as the polymer. The basic configuration is the same as that of the embodiment 20 shown in FIG.

A method for manufacturing this device will be described. First, electrode layers were formed on the surfaces of two substrates by a vapor deposition method. SP-740 as polyimide on the surface of these substrates
A 2% solution (trade name, manufactured by Toray Industries, Inc.) was spin-coated at 2000 rpm to form an alignment film. These substrates were fired at 250 ° C. Thereafter, the surface of the alignment film was exposed and rubbed in one direction with cotton. The rubbing direction was such that the rubbing directions when the two substrates were combined were substantially parallel. With the alignment film surfaces of these two substrates facing each other, the cell thickness is 10 μm.
Fixed so that

In this gap, a mixture of poly-α-methylstyrene and nematic liquid crystal mixed at 120 ° C. at a ratio of 15:85 was sealed. As a nematic liquid crystal, LV-R2
(Product No., manufactured by Roddick) and 1% of S-1011 (Product No., manufactured by Merck) was added as a chiral component. The mixture of the liquid crystal and the polymer was oriented in the liquid crystal phase, cooled at a cooling rate of 50 ° C./min by a temperature controller (see FIG. 17), and brought to room temperature to separate the liquid crystal and the polymer liquid crystal. The shape of the polymer particles thus formed is shown in FIG.
It was similar to

The polymer-dispersed liquid crystal display device manufactured as described above was almost transparent under the condition that no voltage was applied, and a transmittance of 20% was obtained.

When an AC electric field of 10 KHz and 10 V was applied between the two electrodes, a light scattering state was caused due to a difference in refractive index between the polymer and the liquid crystal. At this time, the transmittance was 1%.

[0213] The thermoplastic polymer is not limited to the above-mentioned one, but is a material which is compatible with a liquid crystal and has a liquid crystal phase in a compatible state, and which is phase-separated from the liquid crystal at a use temperature. Can be used. Further, a polymer liquid crystal satisfying this condition can also be used.

The cooling rate for phase-separating the polymer in an oriented state and for adjusting the particle size of the phase-separated polymer to the particle size at which light scattering is most efficient differs depending on the type of polymer. It is desirable to optimize each time to obtain the shape shown or similar.

Note that the alignment film is not limited to the one shown here, and a film capable of aligning liquid crystal in a physical sense can be widely used. In addition, the alignment treatment is effective for only one substrate. When the surfaces of two substrates are subjected to the alignment treatment, the orientation of each other may be optimized according to the intended use.

The liquid crystal preferably has a refractive index anisotropy Δn as large as possible in order to improve the contrast.
A negative substance having a dielectric anisotropy can be used, but in that case, a vertical alignment process must be performed as the alignment process. The optimum content of the liquid crystal is 50 to 97% based on the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The chiral component to be mixed in the liquid crystal can be used even if it is not the one shown here. The mixing ratio is preferably between 0.1% and 5% with respect to the liquid crystal.

Although two substrates are used in the above embodiment, a liquid crystal polymer composite layer can be formed on one substrate. In addition, it is not necessary to form an alignment film on both substrates, and an effect is exhibited only by processing one substrate. Also, the cell thickness need not be the value shown here, and may be determined according to the application.

Although the ultraviolet irradiation device and the temperature controller are arranged on one side of the element, they may be arranged on both sides.

The present invention can be applied not only to the above embodiments but also to computer displays, light control elements, light valves, light control mirrors and the like. Of course, two-terminal elements,
It is easy to produce a large-capacity display in combination with a three-terminal element.

Example 23 FIG. 21 shows a polymer-dispersed liquid crystal display device according to Example 23 of the present invention. In this embodiment, either a liquid crystal having a positive dielectric anisotropy or a liquid crystal having a negative dielectric anisotropy can be used.

A method for manufacturing this device will be described. First, the electrode 230 is placed on the surface of the two substrates 2301 and 2308.
2, 2307 were formed by an evaporation method. One substrate 23
LP-8T (trade name, Shin-Etsu Silicon Co., Ltd.)
) Was spin-coated at 2000 rpm to form a vertical alignment film 2303. Thereafter, the alignment film 2303 was fired at 120 ° C. The vertical alignment treatment can be widely used as long as the liquid crystal is aligned vertically or at an angle close to vertical other than the method described here. JIB on the surface of the other substrate 2308 as polyimide
A 2% solution (trade name, manufactured by Japan Synthetic Rubber Co., Ltd.) (solvent: dimethylacetamide) was spin-coated at 2000 rpm to form a horizontal alignment film 2306. This horizontal alignment film 230
6 was fired at 150 ° C.

Then, the surface of the horizontal alignment film 2306 was exposed and rubbed in one direction with cotton. For the horizontal alignment treatment, in addition to the method shown here, other polymer alignment films can be used, and in addition, any method can be widely used as long as the liquid crystal is aligned, such as an oblique deposition method and an LB film method. The orientation films 2303 and 2306 of these two substrates 2301 and 308 were fixed to face each other so that the cell thickness became 10 μm.
In this gap, a UV curable polymer precursor and liquid crystal were mixed at a ratio of 1: 9.
The mixture mixed at 100 ° C. was sealed. Biphenol methacrylate was used as the ultraviolet-curable polymer precursor. LV-R2 (product number, manufactured by Roddick) was used as the liquid crystal, and S-1011 was used as a chiral component.
(Product number, manufactured by Merck) was mixed at 1%.

The mixture of the UV-curable polymer precursor and the liquid crystal is cooled, oriented, and irradiated with ultraviolet rays to polymerize the UV-curable polymer precursor and to form the polymer 2304 and the liquid crystal 2305. The phases were separated. The portion of the polymer 2304 and the liquid crystal 2305 which is close to the substrate 2301 is vertically oriented with respect to the substrate 2301 due to the influence of the vertical alignment film 2302, but the portion which is close to the substrate 2308 is formed by the horizontal alignment film 2306. Are oriented in parallel to. Therefore, when an electric field is applied to the polymer liquid crystal composite layer, when a liquid crystal having a positive dielectric anisotropy is used, the liquid crystal 2305 in a range close to the substrate 2308 is used.
Responds to an electric field, and conversely, when a liquid crystal having negative dielectric anisotropy is used, the liquid crystal 2305 in a range close to the substrate 2301 responds to the electric field.

The electro-optical characteristics of the device manufactured as described above were measured. The result is shown in FIG. FIG.
The relationship between the voltage value and the transmittance when a 10 KHz AC electric field is applied between the two electrodes and the voltage value is changed is shown. FIG. 23 shows the electro-optical characteristics of the conventional element. As is clear from the comparison between the two figures, the present embodiment is significantly improved in steepness as compared with the above-described embodiment.

Next, the contrast when a time-division driving waveform was applied to the device of this example was measured. The contrast is 13: 1 at 1/4 duty and 5: at 1/8 duty.
It was 3: 1 at 1, 1/16 duty. In the prior art, the time-division driving has been greatly improved since the 1/3 duty is limited.

In this embodiment, any liquid crystal having positive or negative dielectric anisotropy can be used as the liquid crystal. The optimum content of the liquid crystal is 50 to 97% based on the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The chiral component to be mixed in the liquid crystal can be used even if it is not the one shown here. However, the turning ability that determines the pitch of the liquid crystal is important. That is, the pitch of the liquid crystal when the chiral component is mixed is P = 1 / 34C
Can be written as Where P is the pitch in μm,
C is the concentration and the unit is%. The concentration is about 0.1% to 5%, which is 0.29 to 0.0059 μm in terms of pitch.

Even when other chiral components are used, the pitch of the liquid crystal must be within this range. Of course, there is no problem even if the chiral component is a multi-component system. As a polymer,
Any polymer precursor that can be aligned in a state mixed with a liquid crystal and photopolymerized in that state can be used in the same manner. As long as a polymer precursor having a skeleton similar to a liquid crystal molecule, a display element having excellent contrast transmittance can be manufactured as in the example shown here.

(Embodiment 24) In this embodiment, a polymer liquid crystal is used as a polymer. The basic configuration is shown in FIG.
This is the same as Example 23 shown in FIG. However, a mixture of a side chain type polymer liquid crystal having a cyanobiphenol group shown in Chemical formula 19 and a liquid crystal in a ratio of 1: 9 at 120 ° C. is sealed in a gap between the two substrates, and the mixture is cooled. The difference is that the liquid crystal and the polymer liquid crystal are phase-separated by aligning and setting the temperature to 70 ° C. As the liquid crystal, RDP80616 was used, and 1% of S-1011 (product number, manufactured by Merck) was added as a chiral component.

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With respect to the element manufactured as described above,
When the electro-optical characteristics were measured, the same results as in Example 23 were obtained.

As the polymer, the liquid crystal is compatible with the liquid crystal at a temperature higher than the operating temperature, and is further oriented in the compatible liquid crystal phase, and can be cooled to phase separate the polymer and the liquid crystal at the operating temperature. If there is, it can be used similarly regardless of the side chain type main chain type. For example, polymer liquid crystals shown in Chemical formulas 20 to 26 can be used. Of course, the polymer shown here is only an example, and it is desirable to optimize the structure by combining it with a liquid crystal or the like. In this embodiment, when the compatibility between the liquid crystal and the polymer liquid crystal is poor, a cosolvent of the liquid crystal and the polymer liquid crystal can be used. In this case, it is preferable to use a polymer liquid crystal which becomes a liquid crystal phase when a co-solvent is mixed, and after the alignment, distill off the solvent and phase-separate the liquid crystal from the polymer liquid crystal.

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In the above embodiment, two substrates are used.
A liquid crystal polymer composite layer can be formed on one substrate. As the liquid crystal, a liquid crystal having positive or negative dielectric anisotropy can be used. Also, the cell thickness need not be the value shown here, and may be determined according to the application. The present invention can be used not only as a transmission type but also as a reflection type. Further, a large-capacity display body can be manufactured in combination with a three-terminal element or a two-terminal element. In the above embodiment, a side chain type polymer liquid crystal having a cyanobiphenol group was used. However, the present invention is not limited to this, and a thermoplastic polymer or a thermosetting polymer can also be used.

The present invention can be applied not only to the above embodiments but also to computer displays, light control elements, light valves, light control mirrors and the like.

Embodiment 25 FIG. 24 shows a polymer dispersed liquid crystal display device according to a twenty-fifth embodiment of the present invention. In this embodiment, a dichroic dye is added to the liquid crystal, and one of the electrodes also serves as a reflection layer.

A method for manufacturing this device will be described. First, the electrodes 2502 and 2
507 was formed by an evaporation method. The electrode 2507 was made of aluminum because it also served as a reflective layer. Electrode 2502
Is a transparent electrode (ITO: indium-tin-oxide). A 2% solution of JIB (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.) (solvent: dimethylacetamide) was spin-coated at 2000 rpm on the electrodes 2502 and 2507 to form alignment films 2503 and 2506. Fired at ℃. Thereafter, the surfaces of the alignment films 2503 and 2506 were exposed and rubbed in one direction with cotton. For the horizontal alignment treatment, in addition to the method shown here, other polymer alignment films can be used, and in addition, any method can be widely used as long as the liquid crystal is aligned, such as an oblique deposition method and an LB film method. The substrate may be simply rubbed without providing the alignment film.

With the alignment films 2503 and 2506 of these two substrates 2501 and 508 facing each other, a cell thickness of 5
It was fixed to μm. The ultraviolet curable polymer precursor and the liquid crystal were mixed and sealed at 100 ° C. at a ratio of 15:85 in the gap. Biphenol methacrylate was used as the ultraviolet-curable polymer precursor. LV-2R having a positive dielectric anisotropy was used as the liquid crystal, and S-1011 (product number, manufactured by Merck) as a chiral component, and S-344 as a dichroic dye were respectively 97: 1: 2. At a rate of Subsequently, the mixture of the UV-curable polymer precursor and the liquid crystal is gradually cooled to orient them, and is further irradiated with ultraviolet light to polymerize the UV-curable polymer precursor, and phase-separate as the liquid crystal 2505 and the polymer 2504. I let it.

The operation principle of the display device manufactured as described above will be described. The polymer 2504 shown in FIG.
The liquid crystal 2505 exhibits the same refractive index anisotropy, and has a refractive index in the direction parallel to the alignment direction of about 1.5 and a refractive index in the direction perpendicular to the alignment direction of about 1.7.

Accordingly, as shown in FIG. 24A, when no electric field is applied, the liquid crystal 2505 is oriented in the same direction as the polymer 2504, so that the liquid crystal 2505 and the polymer in a direction perpendicular to the substrates 2501 and 408 are oriented. The refractive indices of 2504 match. Here, the dichroic dye is added to the liquid crystal 2504 and is oriented in the same direction as the liquid crystal 2505.
, That is, light incident from the direction perpendicular to the substrates 2501 and 408 is most effectively absorbed. Therefore, at this time, the element displays black, which is the color of the dichroic dye.

On the other hand, as shown in FIG.
When an electric field is applied to the polymer liquid crystal composite layer by connecting a power source between the liquid crystal 2250 and the liquid crystal 2505, only the liquid crystal 2505 remains in the electric field direction while the orientation direction of the polymer 2504 remains unchanged.
That is, they are oriented in a direction perpendicular to the substrates 2501 and 508. Therefore, in the electric field direction perpendicular to the substrates 2501 and 508, the refractive index of the polymer 2504 remains about 1.7, whereas the refractive index of the liquid crystal 2505 becomes about 1.5. Therefore, the difference in the refractive index between the polymer 2504 and the liquid crystal 2505 in the direction of the electric field is about 0.2, and
Light incident from directions perpendicular to 501 and 2508 will be scattered. Here, since the dichroic dye is also oriented in the same direction as the liquid crystal 2505, that is, in the direction of the electric field, the dye is not absorbed in the direction of the electric field and becomes white and cloudy.

If the chiral component is not mixed with the nematic liquid crystal 2508, the vibration direction is changed to the plane on which the liquid crystal 2505 can move, that is, the plane parallel to the paper plane in FIG. Since only the polarized light having the modulation is modulated, the contrast cannot be sufficiently improved. When the chiral component is mixed with the liquid crystal 2505 as in this embodiment, the polarized light having a vibration direction in a direction other than the direction parallel to the plane in which the liquid crystal can move out of the light perpendicularly incident on the substrates 2501 and 508 is obtained. However, since the modulation is effectively performed, the contrast can be sufficiently improved.

Next, the electro-optical characteristics of the device were measured. When an AC electric field of 1 KHz was applied between the two electrodes and the voltage value was changed, the relationship between the voltage value and the reflectance was measured.
The result shown in FIG. The driving voltage is about one-tenth that of the electro-optical characteristics of the conventional reflective polymer dispersed liquid crystal display device.
And the appearance has been improved. Electrodes 2502, 25
If 07 is set as a character shape, this display element is displayed as a white character floating in a black mirror. Also, the steepness was excellent, and time-division driving with 1/4 duty was possible.

The liquid crystal is not limited to the liquid crystal shown in the above embodiment, and the content of the liquid crystal is 50 to 97% of the whole.
Is optimal. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The content of dichroic dye in the liquid crystal is 1
1010%, preferably 2-5%. This may be optimized depending on the type and use of the dye. The content of the chiral component in the liquid crystal is preferably about 0.1 to 5%. Of course, this depends on the chiral component used, and good results are obtained with a cholesteric pitch of 0.3 to 0.006 μm. Of course, there is no problem even if the chiral component is a multi-component system.

As the polymer precursor, besides biphenol ester, those which are well mixed with liquid crystal and have a liquid crystal phase in a mixed state, and which can be polymerized by light can be used. As long as a polymer precursor having a skeleton similar to a liquid crystal molecule, a display element having excellent contrast transmittance can be manufactured as in the example shown here. As the electrode also serving as the reflective layer, any material that reflects light can be used in addition to aluminum.

(Embodiment 26) In this embodiment, the basic configuration is the same as that of embodiment 25 shown in FIG.
7, a transparent electrode is used, and a reflective layer is provided on the back side of the substrate 2508.

According to this embodiment, when the display is viewed from the front, the same display as that of the twenty-fifth embodiment is observed. Further, when viewed from an oblique direction, the parallax corresponding to the thickness of the substrate 2508 is formed, and the image is doubled. There is a feature that looks like.

The present invention can be applied to a bright large-capacity computer display, a light control element, a light valve, a light control mirror, and the like in combination with an active element such as an MIM element or a TFT element.

(Embodiment 27) FIG. 26 shows a polymer dispersed liquid crystal display device according to a twenty-seventh embodiment of the present invention. In this example, biphenylmethanol methacrylate and biphenol methacrylate were used as polymers.

A method for manufacturing this device will be described. First, the electrodes 270 are placed on the surfaces of the two substrates 2701 and 2708.
2,2707 was formed by an evaporation method. Electrodes 2702,
A 2% solution of JIB (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.) (solvent is dimethylacetamide) is spin-coated as a polyimide on 2000 at 2000 rpm to form an alignment film 270.
3,2706. These alignment films 2703 and 2706 are
It was fired at 150 ° C. After that, the alignment films 2703 and 2706
Was rubbed in one direction with cotton. For the horizontal alignment treatment, in addition to the method shown here, other polymer alignment films can be used, and in addition, any method can be widely used as long as the liquid crystal is aligned, such as an oblique deposition method and an LB film method. Alignment films 2703 and 270 of these two substrates 2701 and 2708
6 were fixed to each other so that the cell thickness became 10 μm.

In this gap, a mixture of a 1: 1 mixture of biphenol methacrylate and methacrylic acid ester of biphenylmethanol and a liquid crystal at a ratio of 1: 9 at 100 ° C. was sealed as an ultraviolet curable polymer precursor. As liquid crystal, LV-R2 (product number, manufactured by Roddick)
Was mixed with 1% of S-1011 (product number, manufactured by Merck) as a chiral component. Subsequently, the mixture of the polymer precursor and the liquid crystal is cooled down, and these are aligned, and the polymer precursor is polymerized by irradiating ultraviolet rays.
And polymer 2704 to cause phase separation.

[0257] The electro-optical characteristics of the device thus manufactured were measured. When a 10 KHz AC electric field was applied between the two electrodes and the voltage value was changed to show the relationship between the voltage value and the transmittance, the result shown in FIG. 27 was obtained. FIG. 28 shows the electro-optical characteristics of a conventional polymer-dispersed liquid crystal display device. As shown in both figures, the device of the present embodiment has a markedly improved steepness as compared with the conventional device. Next, a time-division driving waveform was applied to measure the contrast. The contrast at this time is 33: 1 at 1/4 duty and 2 at 1/8 duty.
7: 1, 4: 1 at 1/16 duty. In the prior art, the time-division driving has been greatly improved since the 1/3 duty is limited.

The content of the liquid crystal is 50 to 97% of the whole.
Is optimal. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The chiral component to be mixed in the liquid crystal can be used even if it is not the one shown here. However,
The turning ability that determines the pitch of the liquid crystal is important. That is,
When the chiral component is mixed, the pitch of the liquid crystal is P = 1.
/ 34C. Here, P is the pitch and the unit is μm, and C is the concentration and the unit is%. The concentration is 0.1% -5%
It is about 0.29 to 0.0059 μm in terms of pitch.
Even when other chiral components are used, the pitch of the liquid crystal needs to be within this range. Of course, there is no problem even if the chiral component is a multi-component system.

As the content of biphenylmethanol ester increases, the steepness in the threshold characteristics becomes better, but if too much is added, optical response to an electric field is not obtained. Therefore, the allowable content of biphenylmethanol ester in the polymer varies greatly depending on the type of liquid crystal used, but when LV-R2 (product number, manufactured by Roddick) or RDP80616 is used as the liquid crystal, the content ratio in the polymer is 80%. % Or less.

As the polymer, any polymer precursor which can be aligned in a state mixed with liquid crystal and photopolymerized in that state can be used in the same manner. However, in order to obtain the effect of this embodiment, one polymer precursor to be mixed must be a vinyl ester derivative of biphenylmethanol.
As long as the polymer precursor has a skeleton similar to liquid crystal molecules, a display element excellent in both threshold characteristics and contrast transmittance can be manufactured as in the example shown here.

(Example 28) In this example, a methacrylic acid ester of naphthol was used as a polymer. The basic configuration is the same as that of the embodiment 27 shown in FIG.

A method for manufacturing this device will be described. The steps up to the alignment processing and assembly of the substrate are the same as those in the twenty-seventh embodiment. A mixture of a 1: 1 mixture of biphenol acrylate and acrylic acid ester of naphthol as a UV-curable polymer precursor and a mixture of liquid crystals at 100 ° C. at 1: 9 were sealed in the gap between the two substrates. RDP80616 was used as the liquid crystal, and S-1011 (product number,
(Merck) was mixed at 1%. Subsequently, the mixture of the UV-curable polymer precursor and the liquid crystal was cooled, and they were oriented, and they were aligned, irradiated with UV light to polymerize the UV-curable polymer precursor and phase-separated the liquid crystal and the polymer. .

When the electro-optical characteristics of the device manufactured as described above were measured, almost the same electro-optical characteristics as in Example 27 were obtained. Regarding the time-division driving characteristics, the contrast was 20: 1 at 1/4 duty, 15: 1 at 1/8 duty, and 4: 1 at 1/16 duty.

The content of the liquid crystal is 50 to 50 with respect to the polymer precursor.
95% is optimal. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The chiral component to be mixed in the liquid crystal can be used even if it is not the one shown here. However, the turning ability that determines the pitch of the liquid crystal is important. That is, the pitch of the liquid crystal when the chiral component is mixed is P
= 1 / 34C. Here, P is the pitch and the unit is μm, and C is the concentration and the unit is%. The concentration is 0.1%
The pitch is about 0.29 to 0.0059 μm. Even when other chiral components are used, the pitch of the liquid crystal needs to be within this range. Of course, there is no problem even if the chiral component is a multi-component system.

As the content of the naphthol ester increases, the steepness in the threshold characteristic becomes better, but if it is added too much, the optical response to the electric field is stopped. Therefore, the allowable content of naphthol ester in the polymer varies greatly depending on the type of liquid crystal used.
(Product number, manufactured by Roddick) or RDP8061
When using 6, the content ratio in the polymer must be 80% or less. As the polymer, any polymer precursor that can be aligned in a state mixed with a liquid crystal and photopolymerized in that state can be used in the same manner. However, in order to obtain the effect of this embodiment, one polymer precursor to be mixed must be a vinyl ester derivative of naphthol. As long as the polymer precursor has a skeleton similar to liquid crystal molecules, a display element excellent in both threshold characteristics and contrast transmittance can be manufactured as in the example shown here.

The present invention can be applied not only to the above-mentioned embodiments but also to further improved and large-sized medium and medium-capacity computer displays, light control elements, light valves, light control mirrors and the like.

(Embodiment 29) FIG. 29 shows a polymer dispersed liquid crystal display device according to a twenty-ninth embodiment of the present invention.

A method for manufacturing this device will be described. First, the electrode layers 29 are formed on the surfaces of the two substrates 2901 and 2908.
02,2907 was formed by an evaporation method. These substrates were placed in a 2% solution of LP-8T (trade name, manufactured by Shin-Etsu Silicon).
Immersion for 0 minutes, washing with water, drying at 130 ° C., orientation film 2903
2906. These two substrates 2901, 2908
The alignment films 2903 and 2906 are fixed so that the cell thickness becomes 10 μm.

A mixture of paraphenylphenol methacrylate and liquid crystal at 15:85 at 100 ° C. was sealed in the gap. As the liquid crystal, RDN007775
(Product No., manufactured by Roddick Co., Ltd.), and S-344 (Product No., manufactured by Mitsui Toatsu Dye) was mixed at a ratio of 98: 2 as a dichroic dye. Subsequently, the mixture of the polymer precursor and the liquid crystal is gradually cooled to orient them, and is irradiated with ultraviolet rays at room temperature, so that the liquid crystal 2905 and the polymer 290 are irradiated.
And 4 were phase separated.

The device manufactured in this manner is shown in FIG.
As shown in the figure, when no voltage is applied, it is almost transparent, the transmittance is 68%, and 10KHz20V is applied between the two electrodes.
When an alternating electric field is applied, light is blocked and the transmittance is 10%.
Met.

The principle of operation of the display element of this embodiment will be described. As shown in FIG.
It is oriented perpendicular to 1,908, exhibits the same refractive index anisotropy as the liquid crystal 2905, and has a refractive index of about 1.5 in the electric field direction. Therefore, as shown in FIG. 29A, when no electric field is applied, there is no difference in the refractive index between the liquid crystal 2905 and the polymer 2904 in the electric field direction.
Since it is oriented in the same direction as 5, it becomes colorless and becomes transparent.

When an electric field is applied as shown in FIG. 29 (b), only the liquid crystal 2905 is oriented horizontally with respect to the substrates 2901 and 2908 while keeping the polymer 2904 as it is.
While the refractive index of the polymer 2904 remains at about 1.5, the refractive index of the liquid crystal 2905 becomes about 1.7. Therefore, the difference in the refractive index between the polymer 2904 and the liquid crystal 2905 is about 0.2, and the dichroic dye is scattered in the color of the dye because it is oriented in the same direction as the liquid crystal.

Incidentally, the polymer is a substance which shows a liquid crystal phase even when mixed with liquid crystal.
Preferably, a biphenyl skeleton is introduced. Furthermore, it must be capable of ultraviolet polymerization in the liquid crystal phase. Even if the polymer does not have a benzene skeleton, any polymer can be used as long as it is aligned with the liquid crystal. The alignment film is not limited to LP-8T (trade name, manufactured by Shin-Etsu Silicon), and a material that vertically aligns the liquid crystal, such as DMOAP and stearic acid, can be widely used. In addition, the alignment treatment is effective for only one substrate.

The liquid crystal is not limited to the liquid crystal shown here, and any liquid crystal having a negative dielectric anisotropy may be used. The larger the refractive index anisotropy, the higher the contrast.
The optimum content of the liquid crystal is 50 to 97% based on the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. The dichroic dyes are not limited to those shown here, but those having a higher dichroic ratio can increase the contrast.

(Embodiment 30) This embodiment is a modification of the embodiment 29 which is of the reflection type. Example 2 shown in FIG.
9, an electrode 2907 formed on a substrate 2908 is changed from a transparent conductive material to a metal material such as aluminum.

In this example, when the cell thickness was the same as in Example 29, the transmittance (reflectance) at the time of scattering could be reduced by half. That is, the contrast was doubled. Example 29
In order to obtain the same contrast as in the above, there is an advantage that the driving voltage can be halved because a half cell thickness is sufficient. Specifically, the driving voltage was 5 V with a cell thickness of 5 μm.

When the electrode 2907 also serves as a reflection layer as in this embodiment, the portion in the transmission state becomes a mirror due to reflection from the back and is very difficult to see, so that the surface of the element has a low scattering degree. It is good to arrange a scattering plate. Also, the electrode 290
7 may be a normal transparent electrode, and a reflection plate with a scattering plate may be arranged on the back side of the element.

In the above embodiment, two substrates are used. However, a liquid crystal polymer composite layer can be formed on one substrate. Also, the cell thickness need not be the value shown here, and may be determined according to the application.

The present invention is applicable not only to the above-described embodiment but also to the MIM
It can be combined with an element or a TFT element, and can be applied to a large-capacity display. Further, the present invention can be applied to a light control element, a light valve, a light control mirror, and the like.

(Embodiment 31) FIG. 31 shows a polymer dispersed liquid crystal display device according to a thirty-first embodiment of the present invention. In this embodiment, a retardation plate 3108 and a reflection layer 3109 are provided.

A method for manufacturing this device will be described. First, a glass substrate 3101 having a flat surface and a retardation plate 310
8, transparent electrodes 3102 and 3107 were formed by a vapor deposition method. As the retardation plate 3108, a quarter-wave plate was used. Subsequently, an aluminum reflective layer 3109 was formed on the surface of the glass substrate 3110 by an evaporation method. JIB as polyimide on the transparent electrodes 3102 and 310
A 2% dimethylacetamide solution (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated at 3000 rpm for 30 seconds to form alignment films 3103 and 3106. This alignment film 3103
3106 was baked at 130 ° C. and subjected to a rubbing treatment.
As the alignment treatment, only the rubbing treatment may be performed without attaching the alignment films 3103 and 3106. The orientation directions of the alignment films 3103 and 3106 are parallel, and the substrate 3101 and the retardation plate 3108 are arranged so that the optical axis of the quarter-wave plate is at an angle of 45 degrees with the direction of the alignment treatment.

The substrate 3101 and the phase difference plate 3108
Are fixed so that the cell thickness becomes 5 μm. A mixture of biphenol methacrylate and liquid crystal mixed at 15:85 at 100 ° C. was sealed in the gap. As the liquid crystal, ZLI-392
6 (trade name, manufactured by Merck) was used. Subsequently, the mixture of the polymer precursor and the liquid crystal was gradually cooled to orient them, and irradiated with ultraviolet rays at room temperature to effect the polymer precursor and cause phase separation as the liquid crystal 3105 and the polymer 3104. . After that, the substrate 31 on which the reflective layer 21099 is formed
10 were superimposed.

The operation principle of the device according to this embodiment will be described with reference to FIG. Natural light 3 incident on the element of this embodiment
111 is divided by two polarization components. One is a polarized light 3112 parallel to the orientation direction of the polymer 3104, and the other is a polarized light 3112 perpendicular to the orientation direction of the polymer 3104.
Thirteen.

In the case where no voltage is applied to this element, FIG.
Since the refractive index of the liquid crystal 3105 is equal to the refractive index of the polymer 4105 as shown in FIG. 4A, the natural light 3111 incident on the polymer liquid crystal composite layer is totally reflected by the reflection layer 3109, and is reflected by the polymer liquid crystal composite layer and the position. It reciprocates and passes through the phase difference plate 3108. That is, in the state where no voltage is applied, the mere reflection layer 31 is used.
09 only reflects. When an electric field is applied to this element, the liquid crystal 3105 responds to the electric field and the liquid crystal molecules rotate in the direction of the electric field, as shown in FIG.
And the polymer 3104 has a difference in refractive index. Polarized light 3112
Is an extraordinary ray with respect to the liquid crystal 3105 and the polymer 4104, and is scattered due to the difference in the refractive index between the liquid crystal 3105 and the polymer 3104.

The polarization 3113 is composed of the liquid crystal 3105 and the polymer 31.
Since it is an ordinary ray with respect to 04, it is irrelevant to the difference in the refractive index between the liquid crystal 3105 and the polymer 3105 and does not scatter. Since the polarized light 3112 passes back and forth through the retardation plate 3108 before and after incidence on the reflective layer 3109, the polarization direction is rotated by 90 degrees, becomes an extraordinary ray, and enters the polymer liquid crystal composite layer and is scattered. That is, the scattering efficiency with respect to the natural light 3111 is doubled as compared with the conventional display element.

When an AC electric field of 10 V was applied between two opposing electrodes of the device of this example manufactured as described above, and the electrical characteristics were measured, the results shown in FIG. 32 were obtained. Also, for a reflective display element without a quarter-wave plate,
When the same measurement was performed, the electro-optical characteristics shown in FIG. 33 were obtained. As is evident from the results shown in both figures, it is understood that the device of this example has a higher scattering efficiency than the conventional device.

The structure of the reflecting portion of this embodiment can be applied to all embodiments in which liquid crystal and polymer are horizontally aligned on a substrate.

(Embodiment 32) This embodiment is a guest-host reflective display device in which a dichroic dye is added to the liquid crystal in the embodiment 31. The basic configuration is the same as that of the third embodiment shown in FIG.
Same as 1. However, as a dichroic dye in the liquid crystal, S
-344 (product number, manufactured by Mitsui Toatsu Dye Co., Ltd.) was added at 2%. The color of the dye of S-344 is black.

The operating principle of this device will be described with reference to FIG. Natural light 3211 incident on this element is split into two polarization components. One is a polarized light 3212 parallel to the orientation direction of the polymer, and the other is a polarized light 3213 perpendicular to the orientation direction of the polymer.

In the case where no voltage is applied to this element, FIG.
As shown in FIG. 6 (a), the liquid crystal and the polymer have the same refractive index. However, out of the natural light 3211 incident on the polymer liquid crystal composite layer, the polarized light 3212 having the same
The black dye is efficiently absorbed by S-344 and its intensity is close to zero. On the other hand, of the natural light 3211 incident on the polymer liquid crystal composite layer, the polarized light 3213 perpendicular to the orientation direction of the dye molecules passes through without being absorbed much. The polarized light 3213 that has passed is reciprocated through the retardation plate before and after being reflected by the reflection layer, so that the polarization direction is rotated by 90 degrees. Thereafter, when the light is incident on the polymer composite layer, it is efficiently absorbed by S-344 as a black dye, and the intensity is close to zero.

When an electric field is applied to this element, FIG.
As shown in (2), the dye molecules are rotated in the direction of the electric field by the liquid crystal molecules, and the polarized lights 3212 and 3213 are hardly absorbed. For this reason, similarly to FIG.
2, 3213 are dispersed due to the difference in the refractive index between the liquid crystal and the polymer when reciprocating through the polymer liquid crystal composite layer. Doubled compared to

With respect to the device manufactured by the above method,
When the electrical characteristics were measured, the result shown by the solid line in FIG. 35 was obtained. When the electro-optical characteristics of the conventional guest-host reflective display element without a quarter-wave plate were measured, the result indicated by the broken line in FIG. 35 was obtained. As is clear from the results, it is understood that the present embodiment has improved contrast and improved threshold characteristics as compared with the related art.

(Embodiment 33) FIG. 37 shows one substrate of a polymer dispersed liquid crystal display device according to a thirty-third embodiment of the present invention. In this embodiment, a phase difference plate such as a quarter-wave plate also serves as a substrate. That is, a reflective layer 3309 is formed by a vapor deposition method on a hard retardation plate 3310 also serving as a substrate, and a transparent electrode 3307 and an alignment film 3306 are formed thereon.

In this example, the electro-optical characteristics of the reflection type display device as shown in FIG. 32 were also shown. This reflective display element can be reduced in weight because it has one less substrate than the element having the structure of FIG. 31, and various applications can be considered.

In the above examples, a liquid crystal having a large birefringence anisotropy Δn and a polymer precursor which is well mixed with the liquid crystal and has a liquid crystal phase and which has a similar refractive index are used. Good to use. The ratio of liquid crystal to polymer is preferably between 95: 5 and 80:20. If the amount of liquid crystal is larger than this, no response occurs, and if the amount of liquid crystal is small, the driving voltage becomes too high.

(Embodiment 34) FIG. 38 shows a polymer dispersed liquid crystal display device according to a thirty-fourth embodiment of the present invention. This embodiment is used as a polarizing element.

A method for fabricating this device will be described. First, the electrode layers 34 are provided on the surfaces of the two substrates 3401 and 3408.
02,3407 was formed by an evaporation method. On these electrodes 3402 and 3407, polyimide (SP7 manufactured by Toray Industries, Inc.) is used.
40 2% dimethylacetamide solution) and baked at 250 ° C. to form alignment films 3403 and 3406. The alignment film 34 of these two substrates 3401 and 3408
03, 3406 was rubbed with a cloth in one direction, and the rubbing directions were parallel to each other, and fixed so that the cell thickness became 10 μm. A mixture of paraphenylphenol methacrylate and liquid crystal mixed at 15:85 at 100 ° C. was sealed in the gap. LV-R2 (product number, manufactured by Roddick) was used as the liquid crystal.

Subsequently, the mixture of the polymer precursor and the liquid crystal was gradually cooled to orient the mixture, and the polymer precursor was cured by irradiating ultraviolet rays at room temperature, and the liquid crystal 3 was cooled.
405 and polymer 3405 were subjected to phase separation. The operation principle of the present embodiment will be described. As shown in FIG. 38, the polymer 3404 is applied to the substrates 3401 and 340 along the liquid crystal 3405.
8 and the liquid crystal 3405
Shows the same refractive index anisotropy as 1.5, and the refractive index in the electric field direction is 1.5.
It is about. Therefore, when no electric field is applied, there is no difference in the refractive index between the liquid crystal 3405 and the polymer 3404 in the direction of the electric field as shown in FIG.

With respect to polarized light that oscillates in a direction parallel to the orientation direction of the polymer 3404 when an electric field is applied as shown in FIG. 38 (b), only the liquid crystal 3405 is oriented in the direction of the electric field. Although the index remains at about 1.5, the refractive index of the liquid crystal 3405 becomes about 1.7. Therefore, the difference in refractive index between the polymer 3404 and the liquid crystal 3405 is
Light scattering is about 0.2. On the other hand, with respect to polarized light that oscillates perpendicularly to the alignment direction of the polymer 3405, the refractive index of the polymer 3404 also increases even when an electric field is applied.
Has a refractive index of about 1.5, and has no difference in refractive index. Therefore, polarized light that vibrates perpendicularly to the orientation direction of the polymer 3405 passes through this element. That is, this element can be used as a polarizing element.

When an AC electric field of 10 KHz and 20 V was applied between the two electrodes of the device manufactured by the above-mentioned method, nearly 100% of the polarized light oscillating in the alignment direction was scattered, and almost the polarized light orthogonal to this was transmitted. FIG. 39 shows an electro-optical characteristic diagram of the polarizing element of the present invention. When a sufficient electric field is applied,
It can be seen that polarized light in one vibration direction is sufficiently scattered, and the amount of transmitted light is reduced to about half.

Incidentally, the polymer is a compound which, even when mixed as a liquid crystal, exhibits a liquid crystal phase and has a benzene skeleton, preferably a biphenyl skeleton, introduced into the polymer. Further, it must be capable of ultraviolet polymerization in the liquid crystal phase. Even if the polymer does not have a benzene skeleton, any polymer can be used as long as it is aligned with the liquid crystal. The alignment film is not limited to polyimide, and may not be required to be strong, and can be widely used as long as it is a process for aligning the liquid crystal. The liquid crystal is not limited to the liquid crystal shown in the above embodiment, but the contrast can be improved by using a liquid crystal having a large refractive index anisotropy. The optimum content of the liquid crystal is 50 to 97% based on the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained.

(Embodiment 35) FIG. 40 shows a polymer dispersed liquid crystal display device according to a thirty-fifth embodiment of the present invention. In the present example, two elements are combined so that the polarization directions are orthogonal to each other, using the element according to Example 34 as a polarizing element. The basic configuration is the same as that of the embodiment 34. FIG.
At 0, a black circle indicates that the orientation direction is perpendicular to the paper surface. The same applies to other drawings.

The operation principle of this embodiment will be described. In the state where no electric field is applied, as shown in FIG. 40 (a), since the refractive index of the polymer 3404 and that of the liquid crystal 3405 are equal in each polarizing element, all the incident light passes through without polarization.

When an electric field is applied, as shown in FIG.
Among the incident light, polarized light parallel to the orientation direction of the polymer 3404 of the first polarizing element is scattered by the first polarizing element,
Polarized light orthogonal to this passes through the first element and reaches the second polarizing element. Since the polarization direction of the light reaching the second element is parallel to the orientation direction of the second element, the light is effectively scattered. That is, when an electric field is applied, incident light is completely scattered.

FIG. 41 shows the electro-optical characteristics of this example. 75% transmittance when no electric field is applied, transmittance when electric field is applied
1% was obtained.

The present invention is applicable not only to the present embodiment but also to the MIM
It can be combined with an element or a TFT element, and can be applied to a large-capacity display. Further, the present invention can be applied to a light control element, a light valve, a light control mirror, and the like.

(Embodiment 36) FIG. 42 shows a polymer-dispersed liquid crystal display device according to a 36th embodiment of the present invention. In this embodiment, a photo-curing type is used as a polymer precursor.

A method for manufacturing this display element will be described.
First, transparent electrodes 3602 and 3607 were formed on the surfaces of transparent substrates 3601 and 3608 having a flat surface by an evaporation method. Further, JIB (trade name, Nippon Synthetic Rubber Co., Ltd.) is used as a polyimide on these transparent electrodes 3602, 3607.
2) solution was spin-coated at 2000 rpm to form alignment films 3603 and 3606. Thus, the transparent electrode 36
The transparent substrates 3601 and 3608 on which 02, 3607 and the alignment films 3603, 3606 were formed were fired at 150 ° C. After that, the surfaces of the alignment films 3603 and 3606 were exposed and rubbed in one direction with cotton to perform an alignment treatment. The rubbing direction was substantially parallel when the two transparent substrates 3601 and 3608 were combined.

Subsequently, the two transparent substrates 3601, 360
8 were fixed so that their gap was 10 μm. And, in this gap, two kinds of polymer precursor methacrylic acid 4-
A liquid crystal polymer composite phase obtained by mixing biphenyl ester, 4-fluorophenyl methacrylate and liquid crystal at a ratio of 7: 7: 86 at 100 ° C. was sealed. As a liquid crystal,
RDP10248 (trade name, manufactured by Roddick) was used. Subsequently, the mixture of the two kinds of polymer precursors and the liquid crystal was gradually cooled to align them. In this state, when ultraviolet rays were irradiated at room temperature, the two kinds of polymer precursors were polymerized and cured, so that the liquid crystal 3605 and the polymer 360 were polymerized.
4 was phase separated.

When the specific resistance of the device manufactured as described above was measured, the specific resistance was as shown by a solid line in FIG.
It was 2.40 × 10 ¹¹ Ωcm. For the measurement, an LCR meter 4272A manufactured by Yokogawa Hewlett-Packard Co. was used, and an AC electric field of 100 Hz and 2 V was applied between the transparent electrodes 3602 and 3607. Further, when the charge holding state of this display element was measured, the charge holding ratio was 93% as shown by the solid line in FIG. The charge retention rate is a rate at which charges are retained when the electric field is applied and the state is released after a certain period of time. As shown in FIG. 44, an electric field of about 14 V was applied for 60 μs at 100 ms intervals.

On the other hand, the same measurement was performed on an element manufactured by mixing methacrylic acid 4-biphenyl ester alone as a polymer precursor and mixing liquid crystal and the polymer precursor at 85:15 at a ratio of 85:15. The specific resistance was 4.06 × 10 ¹⁰ Ωcm as shown by the broken line, and the charge retention was 32% as shown by the broken line in FIG. Also, methacrylic acid 4-
When fluorophenyl ester was used alone as the polymer precursor, the device could not be produced by polymerization in the same manner. By mixing and using the polymer precursor in this way, the specific resistance and the charge retention were remarkably improved, and a display with almost no flicker was obtained when actually combined with the TFT element and the MIM element.

Here, the polymer precursor is not limited to the present embodiment, and any polymer precursor may be used as long as it is arranged in the same direction as the alignment of the liquid crystal, or even in the case of another direction. Can be used. As the polymerization site, any functional group that can be used as a photocurable polymerization site can be used.

Here, the alignment film is not limited to polyimide, but may be polyvinyl alcohol or any other material capable of aligning the liquid crystal in a certain direction. Further, the alignment film is not necessarily required, and the alignment treatment may be performed only by rubbing the substrates. The material to be rubbed is not limited to cotton. In addition, the alignment treatment is effective for only one substrate. The direction of the substrate alignment treatment is not particularly limited.

Here, it is preferable that the liquid crystal has a refractive index anisotropy Δn as large as possible in order to improve the contrast. Further, a liquid crystal having a positive dielectric anisotropy can be used. The content of the liquid crystal is 50 to
95% is optimal. If the liquid crystal content is less than this, the liquid crystal does not respond to the electric field, and if it is more than this, the contrast becomes insufficient. In this example, the chiral component was not mixed, but when the chiral component was added in the range of 0.1 to 1%, the threshold characteristics were improved. Also, the polymerized portion of the polymer precursor uses only a photocurable type, but a thermosetting type can be used as long as it is phase-separated in a state of being aligned and dispersed with liquid crystal and each other. .

(Example 37) In this example, a biphenyl derivative containing a fluorine atom was used as one kind of a polymer precursor. That is, methacrylic acid 4- (2-fluoro) biphenyl ester and methacrylic acid 4-biphenyl ester were used as two kinds of polymer precursors. The ratio of these polymer precursors to liquid crystal was 7:
7:86, and other conditions were the same as those in Example 36 described above. As the liquid crystal, RDP10248 (trade name,
Rodik).

Next, the specific resistance and the charge retention of the display element were measured. The specific resistance was 4.64 × 10 ¹⁰ Ωcm as shown by the solid line in FIG. 46, and the charge retention was 95% as shown by the solid line in FIG. %Met. The measurement method was the same as in Example 36. On the other hand, when methacrylic acid 4-biphenyl ester is used alone as the polymer precursor, the specific resistance is shown by a broken line in FIG. 46, and the charge retention is shown by a broken line in FIG. As shown in FIGS. 46 and 47, the display element of this embodiment has significantly improved specific resistance and charge retention ratio as compared with these examples, and when actually combined with a TFT element and an MIM element, almost no flicker occurs. No display was obtained. Also, methacrylic acid 4- (2-fluoro) biphenyl ester was used alone as a polymer precursor, and a device was similarly manufactured and subjected to the same measurement. However, the polymer precursor was not polymerized, and the device could be manufactured. could not.

(Example 38) In this example, a naphthalene derivative was used as one type of the polymer precursor. That is, methacrylic acid 4-
(4'-nonyloxy) biphenyl ester and 2-naphthyl methacrylate were used. The ratio between the polymer precursor and the liquid crystal was 7: 7: 86 in order, and other conditions were the same as those in Example 36 described above. As the liquid crystal, RDP10248 (trade name, manufactured by Rodik) was used.

Next, when the specific resistance and the charge retention of the display element were measured, the specific resistance was 1. as shown by the solid line in FIG.
07 × 10 ¹² Ωcm, and the charge retention was 97% as shown by the solid line in FIG. The measurement method was the same as in Example 36. On the other hand, when methacrylic acid 4- (4'-nonyloxy) biphenyl ester was used alone as a polymer precursor, a device was similarly manufactured and subjected to the same measurement. The specific resistance was 2.07 as shown by a broken line in FIG. × 10 ¹¹ Ωcm, and the charge retention was about 36% as shown by the broken line in FIG. In the case of using methacrylic acid 2-naphthyl ester, which is another kind of polymer precursor, alone, the same method was used, but no element was produced without polymerization.

In the display element of this embodiment, the specific resistance and the charge retention rate are remarkably improved as compared with these examples. When the display element is actually combined with the TFT element and the MIM element, a display with almost no flicker can be obtained. Was.

(Embodiment 39) In this embodiment, a polymer precursor containing neither a fluorine atom nor a naphthalene derivative is used. That is, methacrylic acid 4- (4'-nonyloxy) biphenyl ester and methacrylic acid 4-biphenyl ester were used as two kinds of polymer precursors. Other conditions are the same as those of the above-described embodiment 36.

Next, when the specific resistance and the charge retention of the display element were measured, the specific resistance was 3.times. As shown by the solid line in FIG.
The charge retention was 90 × 10 ¹¹ Ωcm, and the charge retention was 89% as shown by the solid line in FIG. The measurement method was the same as in Example 36. On the other hand, when the polymer precursor was used alone, as described in Examples 36 and 38, FIGS.
I drew it in 1. FIG. 50 shows the specific resistance. The methacrylic acid 4- (4'-nonyloxy) biphenyl ester is indicated by a broken line, and the methacrylic acid 4-biphenyl ester is indicated by a dotted line. In FIG. 51, when used alone, there is no difference in the charge retention ratio between the two, so they are also indicated by broken lines.

The display element of this embodiment is different from the conventional one in that
The specific resistance has been improved, albeit slightly, and the charge retention has been greatly improved. Further, when the display element of this example was actually driven in combination with the TFT element and the MIM element, a clear display could not be obtained due to flicker.

In the above embodiment, two substrates are used, but a liquid crystal polymer composite layer can be formed on one substrate. In addition, it is not necessary to form an alignment film on both substrates, and an effect is exhibited only by processing one substrate. Also, the gap between the two substrates need not be the value shown here, and may be determined according to the application.

The present invention can be applied not only to the above embodiments but also to computer displays, light control elements, light valves, light control mirrors and the like.

Embodiment 40 FIG. 52 shows a polymer dispersed liquid crystal display device according to a fortieth embodiment of the present invention. In this embodiment, in a reflective display element having a structure in which a liquid crystal and a polymer are aligned and dispersed in one direction between two substrates with electrodes, the alignment direction of the polymer is equal to the normal of the substrate and the light of the incident light. It is perpendicular to the plane containing the axis. FIG. 52 is a conceptual diagram when an electric field is applied.

A method for manufacturing this device will be described. First, the electrode 400 is placed on the surface of the two substrates 4001 and 4008.
2,4007 was formed by an evaporation method. These electrodes 4
002, 4007, polyimide (SP740 manufactured by Toray Industries, Inc.)
2% dimethylacetamide solution)
It was baked at 50 ° C. to form alignment films 4003 and 4006. The alignment film 4003 of these two substrates 4001 and 4008
4006 is rubbed in one direction with a cloth to perform an orientation treatment, and the rubbed directions are parallel to each other, and the cell thickness is 10 μm.
fixed to m. In this gap, paraphenylphenol methacrylate and liquid crystal were added at a ratio of 15:85 to 100.
The mixture mixed at ℃ was sealed. The liquid crystal is PNO
O1 (trade name, manufactured by Roddick) was used. Continued,
The mixture of the polymer precursor and the liquid crystal was gradually cooled, oriented, and irradiated with ultraviolet rays at room temperature to cause phase separation as the liquid crystal 4005 and the polymer 4004. A black velvet cloth was used as a background of this element.

This element is arranged as shown in FIG.
When the electro-optical characteristics were measured, the results shown in FIG. 53 were obtained. The incident angle of the incident light 4011 was set to 65 degrees with respect to the normal to the substrate surface. In FIG. 53, the horizontal axis represents the applied voltage (frequency 1 KHz), and the vertical axis represents the reflectance when the perfect scattering plate is 100% reflected. The solid line in FIG.
04 has a normal direction to the substrate 4001 and the incident light 4011
3 shows the electro-optical characteristics when the plane is perpendicular to the plane including the optical axis of FIG. The broken line in FIG.
04 has a normal direction to the substrate 4001 and the incident light 4011
4 shows electro-optical characteristics when the surface is parallel to a plane including the optical axis. As shown in the figure, the solid line has better characteristics than the broken line.

The reason is that the polymer alignment type liquid crystal display element has anisotropic scattering ability. That is, the polarized light vibrating in the alignment direction is effectively scattered. Therefore, polarized light that is orthogonal to the plane including the normal line of the substrate and the optical axis of the incident light is effectively scattered. Normally, in a room, light from the ceiling direction is reflected by a wall and is considerably polarized, and this polarized light is further polarized by the interface of the transparent substrate when entering the element, and this polarization direction is the same as the polymer orientation direction. If they are arranged so as to coincide, they are scattered efficiently.

The polymer is a substance which exhibits a liquid crystal phase when mixed with liquid crystal, and has a benzene skeleton, preferably a biphenyl skeleton, introduced into the polymer. Furthermore, it must be capable of ultraviolet polymerization in the liquid crystal phase. Even if the polymer does not have a benzene skeleton, any polymer can be used as long as it is aligned with the liquid crystal. The alignment film used is not limited to polyimide, and the substrate may be simply rubbed with a cloth without using the alignment film. The alignment treatment can be widely used as long as the liquid crystal is aligned.

The liquid crystal is not limited to the liquid crystal shown in the above embodiment, but the contrast can be improved by using a liquid crystal having a large refractive index anisotropy. The optimum content of the liquid crystal is 50 to 97% based on the whole. If the content of the liquid crystal is less than this, no response to the electric field occurs, and if it is more than this, contrast cannot be obtained. If a dichroic dye is mixed in the liquid crystal, the reflectance when no electric field is applied can be reduced, and the contrast can be improved.

Embodiment 41 FIG. 54 shows a polymer dispersed liquid crystal display device according to a forty-first embodiment of the present invention. In this embodiment, a polarizing plate 4009,
This is one in which a reflection plate 4010 is arranged. The basic configuration is
This is the same as the embodiment 40 shown in FIG. Polarizing plate 4009
Is disposed on the back surface of the device according to Example 40 so that the orientation direction and the polarization direction of the polymer 4004 are orthogonal to each other, and the reflection plate 4010 is further disposed on the back surface. In FIG. 40, an arrow indicates a polarization direction of the polarizing plate 4009.

FIG. 55 shows the electro-optical characteristics in this embodiment. The amount of reflected light when an electric field was applied was 60% of that of a perfect scattering plate, indicating that light was efficiently scattered. According to this embodiment, light having passed through the element according to Embodiment 40 passes through the polarizing plate 4009, is reflected by the reflecting plate 4010, passes through the polarizing plate 4009 again, and passes through the element. It is considered that this light becomes bright because it passes through the element and goes out.

In this embodiment, the polarization direction of the polarizing plate 4009 is made orthogonal to the orientation direction of the polymer 4004. However, similar effects can be obtained if the angle is almost orthogonal. In the above embodiment, the polarizing plate 4009 and the reflecting plate 4010 or the substrate 4008 and the polarizing plate 4009 and the reflecting plate 4010 may be integrated. When a dichroic dye is mixed into the liquid crystal 4005 and the polarization direction of the polarizing plate 4009 is made parallel to the alignment direction of the polymer 4005, the liquid crystal becomes black when no electric field is applied, and the contrast can be improved.

Example 42 FIG. 56 shows a polymer dispersed liquid crystal display device according to Example 42 of the present invention. This embodiment is different from the embodiment 40 in that the phase correction plate 40
13, a light reduction plate 4014 and a reflection plate 4010 are arranged. The basic configuration is the same as that of the embodiment 40 shown in FIG. The phase correction plate 4013 is disposed on the back surface of the device according to Example 40 so that the orientation direction forms an angle of 45 degrees with the orientation direction of the polymer 4004, and the dimming plate 14 and the reflecting plate 10 are further disposed on the back surface. They are arranged in order. Even if the orientation direction of the phase correction plate is not 45 degrees with respect to the orientation direction of the polymer 4004, there is an effect of improving brightness. The phase correction plate 4013 used here is a correction plate having a phase shift of 1/4 wavelength (144 nm) with respect to green light. Of course, other phase correction plates may be used if the positional relationship with the element unit is optimized. Can be used.

FIG. 57 shows an electro-optical characteristic diagram of the display element of this example. The amount of reflected light when an electric field is applied is higher than that of a perfect scattering plate.
It is 80%, which indicates that the light is scattered more efficiently than the previous example. According to this configuration, the light that has passed through the element shown in FIG. 40 is phase-corrected by the phase correction plate 4013, reflected by the dimming plate 4014 and the reflecting plate 4010, passed through the dimming plate 4014 again, and The phase is corrected in 4013, the polarization direction is rotated by 90 degrees, and the light returns to the element. Therefore, the light reflected by the reflection plate 4010 is efficiently scattered again by the element, and thus looks brighter. The light attenuating plate 4014 is necessary to make the element black when no electric field is applied. Although the light attenuating plate 4014 has a transmittance of 60%, it may be optimized depending on the application. In addition, the color can be freely selected.

In this embodiment, the phase correction plate 4013 and the light reduction plate 4014, the light reduction plate 4014 and the reflection plate 4010, or the phase correction plate 4013, the light reduction plate 4014 and the reflection plate 4
010 may be integrated. When a dichroic dye is mixed with the liquid crystal, the contrast can be improved.

The present invention can be combined with not only the above embodiment but also MIM elements and TFT elements, and can be applied to a large-capacity display. Further, the present invention can be applied to a light control element, a light valve, and the like.

[0338]

As described above in detail with reference to the embodiments, the present invention provides a liquid crystal polymer composite layer in which a liquid crystal and a polymer are oriented in a certain direction, thereby achieving a good transparent state when no electric field is applied. Can be realized. If this is used for a car window or the like, it becomes a so-called fail-safe dimming window glass which becomes transparent when the electric field is no longer applied, and is safe. Furthermore, by adding a chiral component to the liquid crystal, it was possible to realize a good scattering state at the time of applying a voltage, and at the same time, the threshold characteristics became better, and the hysteresis in the response observed when the voltage was increased or decreased was reduced. . Further, by providing the reflective layer, it is possible to provide a reflective liquid crystal display element having a low driving voltage, good contrast, and good visibility, and it is also possible to provide a large-capacity display using this display element. It became.

Further, by improving the polymer precursor and using at least two kinds of polymer precursors, it was possible to improve the specific resistance after the device was manufactured and simultaneously improve the charge retention. In addition, by mixing a dichroic dye in the liquid crystal, a good transparent state when no electric field is applied and a good colored scattering state when a voltage is applied can be realized. Also,
By using this electric field control type polarizing element, a bright display element with good contrast and good visibility can be provided. By using the present invention, it is also easy to produce anti-glare polarized sunglasses that can cut polarized light by applying an electric field with ordinary sunglasses.

The present invention is a basic technique for expanding the possibility of applying a polymer-dispersed liquid crystal device to a simple matrix type display device, and at the same time, a large capacity display by a combination with an active matrix type display device. It is also a basic technology that expands possibilities. The present invention is a basic technique for expanding the possibility of application of a polymer dispersion type liquid crystal display device to a simple matrix type display device, and at the same time, the possibility of a large capacity display by combination with an active matrix type display device. It is also a basic technique for expanding

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a cross section of a polymer dispersed liquid crystal display device according to Example 1 of the present invention.

FIG. 2 is a conceptual diagram showing a cross section of a polymer-dispersed liquid crystal display device according to Example 2 of the present invention.

FIG. 3 is a graph showing electro-optical characteristics of a polymer-dispersed liquid crystal display device in Example 2 of the present invention.

FIG. 4 is a graph showing electro-optical characteristics of a conventional polymer-dispersed liquid crystal display device.

FIG. 5 is a conceptual diagram showing a partial cross section of a polymer dispersed liquid crystal display device according to Example 5 of the present invention.

FIG. 6 is a conceptual diagram showing a partial cross section of a polymer dispersed liquid crystal display device according to Example 6 of the present invention.

7A and 7B are conceptual diagrams showing a cross section of a polymer dispersed liquid crystal display element according to Example 7 of the present invention. FIG. 7A shows an operation state when no electric field is applied, and FIG. The operation state at the time of application is shown.

FIG. 8 is a graph showing electro-optical characteristics of a polymer-dispersed liquid crystal display device in Example 7 of the present invention.

FIG. 9 is a graph showing electro-optical characteristics of a conventional polymer-dispersed liquid crystal display device.

FIG. 10 is a graph showing electro-optical characteristics of a polymer-dispersed liquid crystal display device in Example 8 of the present invention.

FIG. 11 is a graph showing electro-optical characteristics of a polymer-dispersed liquid crystal display device in Example 9 of the present invention.

FIG. 12 is a conceptual diagram showing a partial cross section of a polymer-dispersed liquid crystal display device according to Example 11 of the present invention.

FIG. 13 is a conceptual diagram showing a partial cross section of a polymer-dispersed liquid crystal display device according to Example 12 of the present invention.

14 is a conceptual diagram showing a cross section of a polymer-dispersed liquid crystal display device according to Example 13 of the present invention, where FIG. 14A shows an operation state when no electric field is applied, and FIG. The operation at the time of application is shown.

FIG. 15 is a conceptual diagram showing a partial cross section of a polymer dispersed liquid crystal display device according to Example 18 of the present invention.

FIG. 16 is a conceptual diagram showing a partial cross section of a polymer dispersed liquid crystal display device according to Example 19 of the present invention.

FIG. 17 is a conceptual diagram showing one embodiment of a manufacturing apparatus according to the method for manufacturing a polymer dispersed liquid crystal display element of the present invention.

FIG. 18 is a conceptual diagram showing a cross section of a polymer-dispersed liquid crystal display element according to Example 20 of the present invention. FIG. 18 (a) shows an operation state when no electric field is applied, and FIG. The operation state at the time of application is shown.

FIG. 19 is an explanatory view showing an electron micrograph of a cross section of the polymer-dispersed liquid crystal display device of Example 20 of the present invention, which was viewed at a magnification of 50,000 times and at an angle of 45 ° on the substrate surface.
The rubbing direction is the vertical direction.

FIG. 20 is a graph showing electro-optical characteristics of a polymer dispersed liquid crystal display device according to Example 20 of the present invention.

FIG. 21 is a conceptual diagram showing a cross section of a polymer dispersed liquid crystal display device according to Example 23 of the present invention.

FIG. 22 is a graph showing the electro-optical characteristics of the polymer dispersed liquid crystal display device in Example 23 of the present invention.

FIG. 23 is a graph showing the electro-optical characteristics of the polymer-dispersed liquid crystal display device in the above-described example.

24A and 24B are conceptual diagrams showing a cross section of a polymer-dispersed liquid crystal display device according to Example 25 of the present invention. FIG. 24A shows an operation state when no electric field is applied, and FIG. The operation state at the time of application is shown.

FIG. 25 is a graph showing the electro-optical characteristics of the polymer dispersed liquid crystal display device in Example 25 of the present invention.

26A and 26B are conceptual diagrams showing a cross section of a polymer-dispersed liquid crystal display element according to Example 27 of the present invention. FIG. 26A shows an operation state when no electric field is applied, and FIG. The operation state at the time of application is shown.

FIG. 27 is a graph showing the electro-optical characteristics of the polymer-dispersed liquid crystal display device in Example 27 of the present invention.

FIG. 28 is a graph showing the electro-optical characteristics of the polymer-dispersed liquid crystal display device in the above-described example.

29 is a conceptual diagram showing a cross section of a polymer-dispersed liquid crystal display device according to Example 29 of the present invention. FIG. 29 (a) shows an operation state when no electric field is applied, and FIG. 29 (b) shows an electric field. The operation state at the time of application is shown.

FIG. 30 is a graph showing electro-optical characteristics of a polymer dispersed liquid crystal display device in Example 29 of the present invention.

FIG. 31 is a conceptual diagram showing a cross section of a polymer-dispersed liquid crystal display device according to Example 31 of the present invention. FIG. 31 (a) shows an operation state when no electric field is applied, and FIG. The operation state at the time of application is shown.

FIG. 32 is a graph showing the electro-optical characteristics of the reflective polymer dispersion type liquid crystal display device of the present invention using a quarter-wave plate.

FIG. 33 is a graph showing electro-optical characteristics of a conventional reflective polymer dispersion type liquid crystal display device not using a quarter-wave plate.

FIG. 34 is an explanatory diagram illustrating an optical principle of a polymer-dispersed liquid crystal display element in Example 31 of the present invention.

FIG. 35 is a graph showing electro-optical characteristics of a reflective polymer dispersion type liquid crystal display element. In the figure, a solid line indicates a quarter wavelength plate in the case of the present invention using a quarter wavelength plate, and a dotted line indicates a quarter wavelength plate. This shows a conventional case where no plate is used.

FIG. 36 is an explanatory diagram showing an optical principle of a polymer-dispersed liquid crystal display device according to Example 32 of the present invention.

FIG. 37 is a conceptual diagram showing a section of a polymer-dispersed liquid crystal display device according to Example 33 of the present invention.

38 is a conceptual diagram showing a cross section of a polymer-dispersed liquid crystal display device according to Example 34 of the present invention. FIG. 38 (a) shows an operation state when no electric field is applied, and FIG. The operation state at the time of application is shown.

FIG. 39 is a graph showing the electro-optical characteristics of the polymer dispersed liquid crystal display device in Example 34 of the present invention.

40 is a conceptual diagram showing a cross section of a polymer-dispersed liquid crystal display device according to Example 35 of the present invention. FIG. 40 (a) shows an operation state when no electric field is applied, and FIG. The operation state at the time of application is shown.

FIG. 41 is a graph showing the electro-optical characteristics of the polymer dispersed liquid crystal display device in Example 35 of the present invention.

FIG. 42 is a conceptual diagram showing a cross section of a polymer dispersed liquid crystal display device according to Example 36 of the present invention.

FIG. 43 is a graph showing the relationship between the frequency and the specific resistance of the polymer-aligned polymer-dispersed liquid crystal display element. The solid line indicates Example 36 using two types of polymer precursors, and the dashed line indicates one. Conventional examples using different types of polymer precursors will be described.

FIG. 44 is a graph showing a voltage waveform applied when measuring the charge retention of the polymer-dispersed liquid crystal display element of the present invention, in which an electric field of about 14 V is alternately applied to the positive and negative at an interval of 100 ms for 60 μs. Then, after the application, it is in a released state.

FIG. 45 is a graph showing the charge retention of the polymer-dispersed liquid crystal display element. The solid line is for Example 36 using two types of polymer precursors, and the dotted line is for one type of polymer precursor. A conventional example will be described.

FIG. 46 is a graph showing the relationship between the frequency and the specific resistance of the polymer-dispersed polymer-dispersed liquid crystal display device. The solid line is Example 37 using two types of polymer precursors, and the broken line is one type. A conventional example using a polymer precursor will be described.

FIG. 47 is a graph showing the charge retention of the polymer-dispersed liquid crystal display device. The solid line is Example 37 using two kinds of polymer precursors, and the broken line is one kind of polymer precursor. A conventional example will be described.

FIG. 48 is a graph showing the relationship between the frequency and the specific resistance of the polymer-dispersed liquid crystal display device. The solid line is Example 38 using two kinds of polymer precursors, and the broken line is one kind of polymer precursor. An example of the related art using the method will be described.

FIG. 49 is a graph showing the charge retention of the polymer-dispersed liquid crystal display device. The solid line is Example 38 using two kinds of polymer precursors, and the broken line is one kind of polymer precursor. A conventional example will be described.

FIG. 50 is a graph showing the relationship between the frequency and the specific resistance of the polymer-dispersed polymer-dispersed liquid crystal display device. The solid line is Example 39 using two kinds of polymer precursors, and the broken line is one kind. A conventional example using a polymer precursor will be described.

FIG. 51 is a graph showing the charge retention of the polymer-dispersed liquid crystal display device. The solid line is Example 39 using two kinds of polymer precursors, and the broken line is one kind of polymer precursor. A conventional example will be described.

FIG. 52 is a conceptual diagram showing a polymer-dispersed liquid crystal display device according to Example 40 of the present invention, in which the alignment direction of the liquid crystal coincides with the direction when an electric field is applied. The polymer is an ellipsoid elongated in the direction perpendicular to the plane of the paper, and the orientation direction is perpendicular to the plane of the paper.

FIG. 53 is a graph showing the electro-optical characteristics of the polymer-dispersed liquid crystal display element in Example 40 of the present invention. The solid line indicates the case where incident light is incident from the direction shown in FIG.
The broken line shows the case where the incident light is incident from a direction rotated by 90 degrees with respect to the normal direction of the substrate.

FIG. 54 is a conceptual diagram showing a polymer-dispersed liquid crystal display device according to Example 41 of the present invention, in which a polarizing plate is polarized in the direction of the arrow.

FIG. 55 is a graph showing the electro-optical characteristics of the polymer dispersed liquid crystal display device in Example 41 of the present invention.

FIG. 56 is a conceptual diagram showing a polymer-dispersed liquid crystal display device according to Example 42 of the present invention.

FIG. 57 is a graph showing the electro-optical characteristics of the polymer dispersed liquid crystal display device in Example 42 of the present invention.

58 is a conceptual diagram showing a cross section of a conventional polymer-dispersed liquid crystal polymer-dispersed liquid crystal display element. FIG. 58 (a) shows an operation state when no electric field is applied, and FIG. The operation state at the time is shown.

[Explanation of symbols]

101,301,501,601,701,1101,
1201, 1301, 1801, 1901, 2001,
2301,2501,2701,2901,3101,
3401, 3601, 4001 substrate 102, 302, 502, 602, 702, 1102
1202, 1302, 1802, 1902, 2002
2302, 2502, 2702, 2902, 3102
3402, 3602, 4002 Electrodes 103, 303, 503, 603, 703, 1103
1203, 1303, 1803, 1903, 2003
2303, 2503, 2703, 2903, 3103
3403, 3603, 4003 Orientation film 104, 304, 504, 604, 704, 1104,
1204, 1304, 1804, 1904, 2004,
2304, 2504, 2704, 2904, 3104
3404, 3604, 4004 Polymer 105, 305, 505, 605, 705, 1105,
1205, 1305, 1805, 1905, 2005,
2305, 2505, 2705, 2905, 3105
3405, 3605, 4005 Liquid crystal 106, 306, 506, 606, 706, 1106,
1206, 1306, 1806, 1906, 2006,
2306, 2506, 2706, 2906, 3106
3306, 3406, 3606, 4006 Orientation film 107, 307, 511, 707, 1111, 130
7, 1811, 2007, 2307, 2507, 270
7, 2907, 3107, 3307, 3407, 360
7,4007 electrodes 108,308,508,608,708,1108,
1208, 1308, 1808, 1908, 2008,
2308, 2508, 2708, 2908, 3110,
3408, 3608, 4008 Substrate 509, 609, 1109, 1209, 1809 Pixel electrode 510, 10, 1110, 1810 Insulating layer 613, 1213, 1913 Source electrode 614, 1214, 1914 Drain electrode 615, 1215, 1915 Semiconductor layer 616, 1216 , 1916 Gate insulating layer 617, 1217, 1917 Gate electrode 2009 Ultraviolet irradiation device 3108, 3310 Phase difference plate 3109, 3309 Reflection layer 3111, 3211 Natural light 3112, 3212 Polarization 3113, 3213 Polarization 4009 Polarizer 4010 Reflector 4011 Incident light 4012 Scattering Light 4013 Phase correction plate 4014 Dimmer plate

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[Procedure amendment]

[Submission date] October 28, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

[Title of the Invention] Liquid crystal display device

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

[0016]

According to the present invention, there is provided a liquid crystal display device comprising a liquid crystal polymer composite layer comprising a liquid crystal and a polymer sandwiched between a pair of substrates. The polymer is dispersed in the liquid crystal, and in a state where no voltage is applied, the liquid crystal and the polymer are arranged in substantially the same direction to be in a light transmitting state. It is characterized by being arranged in a direction different from the arrangement direction to be in a light scattering state. Further, in a liquid crystal display element in which a liquid crystal polymer composite layer comprising a liquid crystal and a polymer is sandwiched between a pair of substrates, the liquid crystal polymer composite layer includes the polymer dispersed in the liquid crystal, The polymer has a refractive index substantially matching the refractive index of the liquid crystal with respect to extraordinary light.

 ──────────────────────────────────────────────────続 き Continued on the front page (31) Priority claim number Japanese Patent Application No. 3-26025 (32) Priority date Heisei 3 (1991) February 20 (33) Priority claim country Japan (JP) (31) Priority Claim number Japanese Patent Application No. 3-59126 (32) Priority Date Hei 3 (1991) March 22 (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 3-118619 (32) Priority Japan Heisei 3 (1991) May 23 (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 3-136170 (32) Priority Japan Heisei 3 (1991) June 7 (33) ) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application No.3-140008 (32) Priority date Hei 3 (1991) June 12 (33) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application No. 3-144583 (32) Priority Date Heisei 3 (1991) June 17, (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 3-153116 (32) ) The other day Hei 3 (1991) June 25 (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 3-167972 (32) Priority date Hei 3 (1991) July 9 (33) ) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application No. 3-200716 (32) Priority date Hei 3 (1991) August 9 (33) Priority claim country Japan (JP) (31) Priority Number Japanese Patent Application No. 3-222982 (32) Priority Date Heisei 3 (1991) September 3 (33) Priority Claiming Country Japan (JP)

Claims (48)

[Claims] 1. A liquid crystal polymer composite layer in which a liquid crystal and a polymer are dispersed with each other and the liquid crystal and the polymer are phase-separated. The liquid crystal is aligned in the direction of the electric field by applying an electric field. A polymer dispersed liquid crystal display device in a scattering state, wherein the liquid crystal and the polymer are oriented in the same direction when no electric field is applied. 2. The polymer dispersion according to claim 1, wherein the liquid crystal polymer composite layer is sandwiched between two substrates, and the two substrates have a transparent electrode on an inner surface. Liquid crystal display device. 3. The liquid crystal polymer composite layer is formed on a single substrate, the one substrate having a transparent electrode on the surface, and a transparent electrode on the upper surface of the liquid crystal polymer composite layer. The polymer-dispersed liquid crystal display element according to claim 1, wherein the liquid crystal display element is formed. 4. The liquid crystal according to claim 2, wherein the liquid crystal has a positive dielectric anisotropy, and the liquid crystal and the polymer are aligned in a direction parallel to the substrate when no electric field is applied. Polymer dispersed liquid crystal display device. 5. The liquid crystal according to claim 2, wherein the liquid crystal has a negative dielectric anisotropy, and the liquid crystal and the polymer are aligned in a direction perpendicular to the substrate when no electric field is applied. Polymer dispersed liquid crystal display device. 6. An alignment for aligning the liquid crystal and the polymer of the liquid crystal phase or a polymer precursor to be polymerized into a polymer in a direction parallel to the substrates on at least one inner surface of the two substrates. The polymer-dispersed liquid crystal display device according to claim 4, wherein a treatment is performed. 7. An alignment for vertically aligning the liquid crystal and the polymer of the liquid crystal phase or a polymer precursor to be polymerized into a polymer on the inner surface of at least one of the two substrates. 6. The polymer-dispersed liquid crystal display device according to claim 5, wherein a treatment is performed. 8. An alignment treatment for aligning the liquid crystal and the polymer of the liquid crystal phase or a polymer precursor to be polymerized into a polymer in a direction parallel to the substrate is performed on one of the two substrates. The other of the two substrates is subjected to an alignment treatment for aligning the liquid crystal and the polymer of the liquid crystal phase or a polymer precursor constituting the polymer in a direction perpendicular to the substrate. 3. The polymer-dispersed liquid crystal display device according to claim 2, wherein: 9. The polymer dispersed liquid crystal display device according to claim 6, wherein an alignment film is formed on the substrate as an alignment process. 10. The polymer-dispersed liquid crystal display device according to claim 2, wherein one of the two substrates has an electrode serving also as a reflective layer on an inner surface. 11. The polymer-dispersed liquid crystal display device according to claim 2, wherein a reflection layer is added to one of the two substrates. 12. The polymer-dispersed liquid crystal display device according to claim 3, wherein the one substrate has an electrode serving also as a reflection layer. 13. The polymer dispersed liquid crystal display device according to claim 3, wherein a reflection layer is added to the one substrate. 14. The polymer dispersed liquid crystal display device according to claim 1, wherein the liquid crystal is a nematic liquid crystal containing a chiral component. 15. The polymer dispersed liquid crystal display device according to claim 1, wherein the liquid crystal contains a dichroic dye. 16. The polymer dispersed liquid crystal display device according to claim 1, wherein the polymer is a polymer containing a biphenyl side chain. 17. The polymer-dispersed liquid crystal display device according to claim 1, wherein the polymer is of an ultraviolet curable type. 18. The polymer-dispersed liquid crystal display device according to claim 1, wherein the polymer is a thermosetting type. 19. The polymer dispersed liquid crystal display device according to claim 1, wherein the polymer is a thermoplastic type. 20. The polymer dispersed liquid crystal display device according to claim 1, wherein the polymer is a polymer liquid crystal. 21. The polymer-dispersed liquid crystal display device according to claim 1, wherein the polymer has a co-solvent with the liquid crystal and takes a liquid crystal phase in a state of being dissolved. 22. The polymer-dispersed liquid crystal display device according to claim 1, wherein the polymer is obtained by polymerizing at least two kinds of polymer precursors having a polymer portion and an aromatic ring portion. . 23. The polymer dispersion according to claim 22, wherein at least one kind of the polymer precursor contains a fluorine atom on an aromatic ring portion or a side chain attached to the aromatic ring portion. Liquid crystal display device. 24. The polymer-dispersed liquid crystal display device according to claim 22, wherein at least one of the polymer precursors contains naphthalene, phenyl, biphenyl, or a derivative thereof in an aromatic ring portion. . 25. The polymer dispersed liquid crystal display device according to claim 22, wherein the polymer precursor is polymerized and cured by ultraviolet rays. 26. The liquid crystal display device according to claim 10, wherein a retardation plate is disposed between the liquid crystal polymer composite layer and the reflection layer.
13. The polymer-dispersed liquid crystal display device according to 1, 13, or 12. 27. The polymer-dispersed liquid crystal display device according to claim 26, wherein the optical axis of the retardation plate forms an angle of 45 degrees with the orientation direction of the liquid crystal polymer composite layer. 28. The polymer dispersed liquid crystal display device according to claim 26, wherein a quarter wave plate is used as the retardation plate. 29. The polymer dispersed liquid crystal display device according to claim 26, wherein a transparent electrode is deposited on the surface of the phase difference plate. 30. The method according to claim 10, wherein the reflection layer is deposited on a surface of a phase difference plate.
The reflective polymer-dispersed liquid crystal display device according to the above. 31. The polymer dispersion according to claim 1, wherein two polymer dispersion type liquid crystal display elements in which the liquid crystal and polymer orientation directions in the liquid crystal polymer composite layer are orthogonal to each other are overlapped. Liquid crystal display device. 32. The polymer-dispersed liquid crystal display device according to claim 1, wherein the orientation direction of the polymer is a direction orthogonal to a plane including a normal line of the substrate and an optical axis of incident light. . 33. The polymer-dispersed liquid crystal display device according to claim 32, wherein a polarizing plate and a reflecting plate are arranged on the back surface of the substrate. 34. The polymer-dispersed liquid crystal display device according to claim 32, wherein a phase correction plate, a dimming plate, and a reflection plate are arranged on the back surface of the substrate. 35. A liquid crystal and a thermoplastic polymer are mixed with each other by heating and compatibilizing with each other, and the liquid crystal and the polymer are oriented in the same direction. A method for producing a polymer-dispersed liquid crystal display device, wherein the polymer and the polymer are phase-separated while maintaining the alignment state. 36. A liquid crystal and a polymer precursor are mixed and mixed, and the liquid crystal and the polymer precursor are oriented in the same direction in a liquid crystal phase. Then, the polymer precursor is polymerized to form a polymer. Wherein the liquid crystal and the polymer are phase-separated while maintaining the alignment state, thereby producing a polymer-dispersed liquid crystal display device. 37. A liquid crystal and a thermoplastic polymer are mixed and sealed between two transparent substrates having transparent electrodes, or after sealing, the liquid crystal and the polymer are aligned in the same direction; Then, the polymer is cooled to cure the polymer, whereby the liquid crystal and the polymer are phase-separated while maintaining the alignment state. 38. After a liquid crystal and a polymer precursor are mixed and sealed between two transparent substrates having transparent electrodes, the liquid crystal and the polymer precursor are aligned in the same direction in the liquid crystal phase. Then, by polymerizing the polymer precursor to a polymer, the liquid crystal and the polymer are phase-separated while maintaining the alignment state of the polymer dispersed liquid crystal display element Production method. 39. After a liquid crystal and a thermoplastic polymer are applied on one transparent substrate having a transparent electrode in a compatible state, the liquid crystal and the polymer are aligned in the same direction in the liquid crystal phase. A method of producing a polymer-dispersed liquid crystal display element, wherein the liquid crystal and the polymer are phase-separated while maintaining the alignment state by cooling and curing the polymer. 40. After mixing and applying a liquid crystal and a polymer precursor on one transparent substrate having a transparent electrode, the liquid crystal and the polymer precursor are aligned in the same direction in a liquid crystal phase, Then, the polymer precursor is polymerized to form a polymer, whereby the liquid crystal and the polymer are phase-separated while maintaining the alignment state, and a method of manufacturing a polymer-dispersed liquid crystal display element, . 41. At least one of the inner surfaces of two transparent substrates having transparent electrodes is subjected to an alignment treatment for aligning a liquid crystal and a thermoplastic polymer in a direction parallel or perpendicular to the substrate. The liquid crystal and the polymer are aligned in the same direction in the liquid crystal phase, and then cooled to cure the polymer, so that the polymer is cured. A method for producing a polymer-dispersed liquid crystal display device, wherein the polymer and the polymer are phase-separated while maintaining the alignment state. 42. At least one of the inner surfaces of two transparent substrates having transparent electrodes is subjected to an alignment treatment for aligning a liquid crystal and a polymer precursor in a direction parallel or perpendicular to the substrate, and then the liquid crystal and the polymer are aligned. A precursor and a liquid crystal phase, and the liquid crystal and the polymer precursor are aligned in the same direction in the liquid crystal phase. A method for producing a polymer-dispersed liquid crystal display device, wherein the liquid crystal and the polymer are phase-separated while maintaining an alignment state by using molecules. 43. An alignment treatment for aligning a liquid crystal and a thermoplastic polymer in a direction parallel or perpendicular to the surface of a single transparent substrate having a transparent electrode, and thereafter, the liquid crystal and the polymer are phased. The liquid crystal and the polymer are melted and applied to the one substrate electrode, the liquid crystal and the polymer are aligned in the same direction in a liquid crystal phase, and then cooled and the polymer is cured, whereby the liquid crystal and the polymer are combined. A method for producing a polymer-dispersed liquid crystal display element, wherein phase separation is performed while maintaining an alignment state. 44. An alignment treatment for aligning a liquid crystal and a polymer precursor of a liquid crystal phase in a direction parallel or perpendicular to the substrate on a surface of a single transparent substrate having a transparent electrode. And the liquid crystal and the polymer precursor of the liquid crystal phase are aligned in the same direction, and then polymerized to form a polymer. Wherein the liquid crystal and the polymer are phase-separated while maintaining the alignment state. 45. The particle size at which the polymer best scatters light
The phase separation speed is adjusted under a condition of 0.1 to 10 µm, wherein the phase separation speed is adjusted.
45. The method for producing a polymer-dispersed liquid crystal display device according to 40, 41, 42, 43 or 44. 46. The polymer dispersion according to claim 36, wherein a methacrylate or acrylate of biphenylmethanol or a derivative of these compounds is used as the polymer precursor. Manufacturing method of a liquid crystal display element. 47. The polymer dispersion type according to claim 36, wherein methacrylate or acrylate of naphthol or a derivative of these compounds is used as the polymer precursor. A method for manufacturing a liquid crystal display element. 48. The polymer dispersed liquid crystal display according to claim 46, wherein a mixture of the ester and a methacrylate or acrylate derivative of biphenol is used as the polymer precursor. Device manufacturing method.