JPH0895012A - Liquid crystal display element and its manufacture - Google Patents

Abstract

PURPOSE: To provide a liquid crystal display element with clear phase dissociation between liquid crystal material and polymer material and controlled arrangement and size of a liquid crystal area, higher contrast, greatly improved visualization and restricted change in display property against external pressure and the manufacture of the liquid crystal display element with controlled alignment precision during manufacturing and simplified manufacturing processes. CONSTITUTION: Thin films 5, 6 are formed in areas excluding the picture element portions of a pair of substrates 1, 2 opposed each other so that a value for surface free energy in the areas excluding the picture element portions can be smaller than a value in the picture element portions. The thin films allows photopolymerization material to be hardly centralized in the areas excluding the picture element portions than in the picture element portions and so photopolymerizing reaction to proceed in the areas excluding the picture element portions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a method for manufacturing the same. More specifically, the present invention relates to a liquid crystal display device in which a liquid crystal region is surrounded by polymer walls and a manufacturing method thereof.

Liquid crystal molecules in the liquid crystal region are aligned in axial symmetry. In this device, the viewing angle characteristics of the liquid crystal display device are improved because the alignment state of the liquid crystal molecules is in axial symmetry. In particular,
Flat panel display that utilizes wide viewing angle (personal computer, word processor, amusement equipment,
Television receivers, etc.), display panels using shutter effect, windows, doors, walls, etc.

The liquid crystal molecules in the liquid crystal region are aligned in one direction on at least one of the substrates. In this device, the liquid crystal molecules are aligned on one of the substrates by using the alignment regulating force of the alignment film such as TN and STN modes which have been conventionally used. This is a cell in which a mode for orienting above is created in a polymer wall to prevent deterioration of display characteristics due to variation of cell gap with respect to external pressure. It can be used as a pen-input type display element, a mobile information terminal element, etc., by making the most of its strong property against external pressure.

[0004]

2. Description of the Related Art Conventionally, there are liquid crystal display devices that utilize various display modes. For example, as a liquid crystal display element to which an electro-optical effect is applied, a twisted nematic (TN) type liquid crystal display element using a nematic liquid crystal or a super twisted nematic (STN) type liquid crystal display element has been put into practical use, and the ferroelectric property is also improved. Liquid crystal (FLC)
A liquid crystal display device using is also proposed. These liquid crystal display elements require a polarizing plate and also require an alignment treatment.

On the other hand, as a liquid crystal display element which does not require a polarizing plate, there is an element to which a dynamic scattering (DS) effect or a phase transition (PC) effect is applied. These cells basically have a structure having no polymer wall in the display area.

More recently, as a liquid crystal display element which does not require a polarizing plate and which does not require liquid crystal alignment treatment, there is a method of electrically controlling a transparent or cloudy state by utilizing the birefringence of the liquid crystal. Proposed. This type of liquid crystal display device has a structure in which a display medium in which liquid crystal droplets are dispersed in a polymer material is sandwiched between two opposing substrates, and is called a polymer dispersion type liquid crystal display device. Is called. This polymer dispersion type liquid crystal display element is basically
When a voltage is applied, the orientation of the liquid crystal molecules becomes uniform, and the ordinary refractive index of the liquid crystal molecules and the refractive index of the polymeric material (polymer) that is the support medium match to obtain a transparent state. When no voltage is applied, Display is performed by obtaining a non-transparent state by causing a light scattering state due to the disorder of the alignment of liquid crystal molecules.

As a proposed manufacturing method, a method of encapsulating a liquid crystal in a polymer capsule is disclosed in JP-A-58-501631, for example, a liquid crystal material and a photopolymerizable material are disclosed in JP-A-61-502128. Alternatively, a method of forming liquid crystal droplets in a polymer material by mixing a polymerizable material composed of a heat-polymerizable material and curing the polymerizable material in the mixed material to precipitate a liquid crystal material is disclosed. There is.
These conventional techniques are elements of a mode in which display is realized by electrically controlling scattering-transmission.

An element using a polarizing plate to improve the viewing angle is disclosed in Japanese Patent Laid-Open No. 4-338923 and Japanese Patent Laid-Open No. 4-338923.
JP-A-212928 discloses an element in which the polymer dispersion type liquid crystal element is sandwiched between orthogonal polarizing plates. The element is
Although the effect of improving the viewing angle characteristics is great, there is a problem that the brightness is as low as half that of the TN mode and the utility value is low because depolarization due to scattering is used in principle. . The decrease in contrast due to the scattering that occurs at the interface between the liquid crystal material and the polymer material reduces the interface between the liquid crystal material and the polymer material in the pixel as much as possible,
Moreover, if the arrangement and size of the liquid crystal regions can be controlled so that at least one liquid crystal region exists in one picture element, the problem can be solved. However, at present, the formation of the liquid crystal region is performed by leaving the curing reaction of the polymerizable material to the end or by irradiating the light with uneven irradiation intensity. For this reason, leak light or the like is generated and the polymer material enters the pixel, and the arrangement and size of the liquid crystal region cannot be controlled with high accuracy.

Further, Japanese Patent Laid-Open No. 27242/1993 discloses a method in which the orientation state of a liquid crystal material is disturbed by walls and protrusions of a polymer material to create random domains to improve the viewing angle. However, in this method, the domain is random and the polymer material also enters the pixel portion,
Moreover, the disclination lines between the liquid crystal domains are randomly generated and do not disappear even when a voltage is applied. For these reasons, the conventional liquid crystal display device has a low contrast. Specifically, there is a display defect that the light transmittance is low when no voltage is applied and the black level is low when a voltage is applied.

For the purpose of manufacturing a liquid crystal display device, it has been conventionally practiced to manufacture a device from a mixture of a liquid crystal material and a polymerizable material (prepolymer, resin material) in a single phase. As an example, it is performed in a liquid crystal display element that realizes a display method using scattering, which is a liquid crystal display mode that is completely different from the liquid crystal display mode of the present application. In this conventional method, the prepolymer component is removed as a polymer material by a chemical polymerization process, so that the liquid crystal material basically starts to precipitate at random. Further, as the polymerization proceeds, the remaining prepolymer component becomes a polymeric material and surrounds the liquid crystal region. Alternatively, a mesh network is formed in the liquid crystal material. Although the arrangement and shape of the liquid crystal region and the polymer region at this time are related to the polymerization rate, they are insufficient for achieving the above control purpose. Because, the positions of nuclei at which the precipitation of the liquid crystal material is started are random.
A liquid crystal phase grows from the position of this nucleus as a starting point, and becomes a liquid crystal region while maintaining the position of this nucleus. If the positions of the nuclei are random, the positions after fabrication cannot be controlled. Furthermore,
Further, in order to prevent scattering in the display area, it is necessary to form an independent liquid crystal area having the same size as the picture element or about half the size thereof. When the liquid crystal region is large, the size of the liquid crystal region is controlled by the polymerization rate.In the case where the liquid crystal region is large, it is necessary to control in the velocity region where the polymerization speed is small. Strict control of temperature, heat of reaction, mixing ratio of materials, purity, etc. is required, and there is a problem in that manufacturing is extremely troublesome.

As described above, each polymer dispersion type liquid crystal display device using the polymer liquid crystal composite in which the liquid crystal region is dispersed has a non-uniform shape of the liquid crystal region due to its manufacturing method, and the substrate surface is not uniform. It was difficult to accurately control the position of the liquid crystal region in the direction along the line. In addition, since the position of the liquid crystal region cannot be accurately controlled, the drive voltage differs for each liquid crystal region, and therefore the steepness of the characteristic change related to the threshold value in the electro-optical characteristics is lacking, and the drive voltage becomes relatively high. Was there. As a result, there is a problem that the display quality is lowered.

Further, as described above, the shape of the liquid crystal region is not uniform, and it is difficult to regulate the positional arrangement of the liquid crystal region in the direction along the surface of the substrate with high accuracy. Was difficult. In addition, since the shape of the liquid crystal region is not uniform and it is difficult to precisely control the positional arrangement of the liquid crystal region in the direction along the substrate surface, the method of driving the liquid crystal display element turns the signal on and off. In the case of the duty driving method in which the driving is performed by the averaged signal level, the threshold voltage for driving the liquid crystal material varies, and as a result, the steepness of the electro-optical characteristics decreases, and It was difficult to increase the ratio.

The inventor of the present invention has found a liquid crystal display device of a new display mode, in contrast to the conventional liquid crystal display device having such a problem. One is to divide the liquid crystal material and the polymer material more clearly, to arrange the liquid crystal material in the picture element part and the polymer material in the non-picture element part, and to arrange two substrates facing each other. It is a novel liquid crystal element that can be arranged in a shape to be connected to each other and can serve as a kind of spacer as a polymer wall to improve the impact resistance of the panel.
As a manufacturing method for forming the liquid crystal display element of this display mode, the present inventor has proposed the following two methods so far.

First, a first method of manufacturing a liquid crystal display device is proposed in Japanese Patent Application No. 5-30996. In the proposed manufacturing method, a mixture of a liquid crystal material, a photopolymerizable material, and a photopolymerization initiator is injected between a pair of substrates arranged facing each other, and then a photomask is formed so that a pixel portion serves as a light-shielding portion. By covering one of the substrates and irradiating the mixture with ultraviolet light from the photomask side, the liquid crystal region gathers in the picture element part that is the weak light irradiation area, and the polymer material in the part other than the picture element that is the strong light irradiation area. In a liquid crystal display device having a display medium composed of a liquid crystal region and a polymer wall. In the proposed method of manufacturing a liquid crystal display element, since the picture element portion is used as the light shielding portion using the photomask, the liquid crystal area can be aggregated into the target picture element portion.

Further, the inventor of the present invention has filed Japanese Patent Application No. 6-2548.
No. 5 proposes a manufacturing method using a self-alignment method using an ITO (indium tin oxide) electrode as a photomask. This proposed technology utilizes the property that the ITO electrode absorbs ultraviolet light, uses the ITO electrode as a photomask, and utilizes the difference in the ultraviolet transmittance between the ITO part and the non-ITO part to make the strong and weak regions of light. Is formed, and the liquid crystal material is aggregated in the picture element portion.

The inventor of the present invention aims to achieve complete phase separation without leaving a polymer material in the pixel portion, that is, to completely separate the liquid crystal region and the polymer region (polymer wall) from each other. Although it is being developed, it is actually difficult to completely separate the phase of the liquid crystal material and the polymer material.
That is, in many cases, the polymer material is left in the liquid crystal material or the liquid crystal material is left in the polymer wall. In the former case, the polymer material left behind reduces the aperture ratio of the liquid crystal panel. In addition, the polymer material remains on the alignment film, which deteriorates the alignment state, resulting in deterioration of optical characteristics of the liquid crystal, that is, response speed and contrast. On the other hand, in the latter case, light scattering occurs in the non-picture element part,
Further, it is feared that the mechanical strength of the polymer wall becomes low and the impact resistance effect is lowered. As described above, if the separability between the liquid crystal material and the polymer material is poor, the above problems occur.

[0017]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the manufacturing method disclosed in Japanese Patent No. 928, since the liquid crystal region is formed by using phase separation, it is possible to precisely control the diameter of the liquid crystal region or precisely control the arrangement of the planar liquid crystal regions. Was difficult.

A conventional liquid crystal display device using a polarizing plate has poor viewing angle characteristics and is not suitable for a wide-angle viewing liquid crystal display device. For example, a TN (twisted nematic) liquid crystal display device has the configuration shown in FIG. Specifically, as shown in FIG. 7A, the liquid crystal 9 in which the initial alignment is twisted by 90 ° between the substrates 1 and 2 and the liquid crystal molecules 10 rise in one direction at an angle (pretilt angle). Has a structure sandwiched between. When the voltage is applied from the AC power supply 11, the liquid crystal molecules 10 rise in the same direction and become parallel to the normal direction of the substrates 1 and 2 as shown in FIG. 7C. Since the liquid crystal molecules 10 are inclined, the apparent refractive index is different when the liquid crystal molecules 10 are viewed from the arrow A direction and the arrow B direction as shown in FIG. 7B. For this purpose each direction A,
The display contrast seen from B is greatly different, and in an extreme case, a display abnormality such as an inversion phenomenon occurs. As described above, in the conventional display mode, poor viewing angle characteristics pose a problem.

Recently, the present inventors have filed a patent application No. 5-7837.
In No. 8, the mixture of the liquid crystal material and the photopolymerizable material in the liquid crystal cell was irradiated with ultraviolet rays having regular UV (ultraviolet) irradiation unevenness to regularly phase-separate the liquid crystal material and the polymer material. Proposing an element. In this device, the viewing angle characteristics of the device are dramatically improved by orienting liquid crystal domains or liquid crystal molecules in an axially symmetrical manner.

In this device, as shown in FIG. 8A, the liquid crystal region 7 surrounded by the polymer wall 8 between the substrates 1 and 2.
Is formed for each picture element. Thin films 13 and 14 are formed in regions of the substrates 1 and 2 facing the liquid crystal region 7. The liquid crystal region 7 has a plurality of domains 12, and each domain 12 has a structure in which the initial orientation is twisted by 90 ° and the liquid crystal molecules 10 rise in one direction at an angle (pretilt angle). ing. When a voltage is applied by the AC power supply 11, the liquid crystal molecules 10 rise in the same direction, as shown in FIG.
When it becomes parallel to the normal direction of the substrates 1 and 2 as shown in (c), at the intermediate stage, as shown in FIG.
When a voltage is applied by the power source 11, the liquid crystal molecules 10 rise so as to have a component perpendicular to the substrates 1 and 2 due to the interaction between the liquid crystal molecules 10 and the polymer wall 8. For this reason, the apparent refractive index becomes substantially the same at the positions in the arrow A direction and the arrow B direction, which is very effective in improving the viewing angle characteristics.

However, in order to make the liquid crystal molecules 10 in the picture element have the axially symmetrical orientation which is most effective in improving the viewing angle characteristics, a wall or column of a polymer material is required in the central portion of the picture element. In fact, the liquid crystal region 7 is reduced and the light transmittance when the voltage is OFF is reduced. Further, the disclination line 15 between the liquid crystal domains 12 cannot be controlled, the disclination line 15 cannot be extinguished even when a voltage is applied, and the contrast becomes low.

Further, also in the liquid crystal region, as shown in FIG. 9, a region 8a in which a liquid crystal material and a polymer material are mixed exists between the liquid crystal region 7 and each of the substrates 1 and 2. The liquid crystal molecules in this region 8a do not respond to the external electric field. Therefore, even when the voltage applied between the electrodes 3 and 4 of the substrates 1 and 2 is the saturation voltage, the birefringence of the liquid crystal molecules taken into the polymer material in the region 8a is high. As a result, light leakage occurs, which causes a reduction in the contrast of the liquid crystal display element.

Further, since the liquid crystal material and the polymer material are phase-separated by mask exposure, it is necessary to use an ultraviolet irradiation device having a parallel light source in order to maintain the pattern accuracy, which causes an increase in fixed cost in manufacturing. It was connected.

As described above, how to clearly phase-separate the liquid crystal material and the polymer material has hitherto been a major problem.

The present invention has been made to solve the problems of the above-mentioned respective prior arts, and the first object thereof is to clarify the phase separation between the liquid crystal material and the polymer material, and to arrange the liquid crystal region and A second object is to improve the alignment accuracy at the time of manufacturing by controlling the size and providing a liquid crystal display device having a high contrast, a significantly improved viewing angle characteristic and a suppressed change in the display characteristic with respect to an external pressure. An object of the present invention is to provide a method of manufacturing a liquid crystal display device that can be manufactured and can simplify the manufacturing process.

[0026]

A liquid crystal display device of the present invention includes a pair of substrates including at least one substrate in which a plurality of regions having different surface free energies are formed in a regular pattern, and the pair of substrates. Sandwiched between a pair of substrates, and a polymer wall made of a polymer material formed by curing a polymerizable material, the polymer wall being formed on a part of a plurality of regions where the first surface free energy is defined. A plurality of liquid crystal regions formed of a liquid crystal material substantially surrounded by the polymer wall, the liquid crystal regions being formed on the other part of the plurality of regions where the second surface free energy is defined. Some of the plurality of regions, the other of the plurality of regions, the polymer wall and the liquid crystal region are
The surface free energy γ _p , the second surface free energy γ _E , the surface free energy γ _LC of the liquid crystal material, and the surface free energy γ _M of the polymer material are expressed by the relational expression (γ _E −γ _P ) × ( [gamma] _{LC- [} gamma] _M )> 0 ... The combination is selected so as to satisfy (1), and thereby the above object is achieved.

The first surface energy may be lower than the second surface free energy.

In this way, the gap d ₁ between the pair of substrates in the picture element portion and the gap d ₂ between the pair of substrates at least a part other than the picture element portion have a relationship of d ₁ > d _2. You may.

The gaps d ₁ and d ₂ may be selected so as to satisfy the relationship 0.1 × d ₁ <d ₂ <0.9 × d ₁ (2).

The liquid crystal display element is an active matrix display element, and a substrate having an active element of the pair of substrates has a light shielding region in a portion other than the picture element portion, The other substrate may have a structure in which at least a part other than the picture element portion has a region that partially transmits ultraviolet rays.

Further, the liquid crystal display device of the present invention comprises a pair of substrates which are arranged to face each other, a polymer wall which is provided between the pair of substrates, and a plurality of liquid crystal regions which are surrounded by the polymer wall. The display medium and the at least one substrate of the pair of substrates are formed on at least a portion other than the picture element portion on the surface of the display medium side, and the value of the surface free energy other than the picture element portion And a thin film for making the value smaller than the surface free energy value, whereby the above object is achieved.

70% or more of the picture element may have at least one liquid crystal region having a size of 30% or more of the area of the picture element in one picture element.

The surface free energy other than that of the picture element portion is 7
It may be 5 mN / m or less.

The difference between the surface free energy other than the picture element portion and the surface free energy of the picture element portion is 15 mN / m.
The above may be applied.

Further, in the method for manufacturing a liquid crystal display element of the present invention, at least one of the two substrates has a light-transmitting property, and a space composed of a liquid crystal material and a polymer material is provided between the two substrates. A method for manufacturing a liquid crystal display element in which a composite having a structure is sandwiched, wherein the free energy of a system constituting the element is spatially spatially controlled as a means for controlling the spatial structure at the time of producing the liquid crystal display element. A means for controlling is used, which achieves the above object.

As means for spatially controlling the free energy, means for controlling the interfacial free energy between the composite-side interface of at least one of the substrates and at least one component of the composite may be used. .

A photosensitive resin may be used to control the interface free energy.

As a control of the interface free energy, the surface of the substrate may be modified. As the spatial control of the free energy, the distance of the void between the two substrates is controlled so that the surface area of the phase-separation interface of the composite-constituting material in the case of having a controlled ordered structure at the time of device production. However, the surface free energy of the phase separation interface may be controlled by configuring the substrate to be smaller than the surface area in the case of the disordered structure.

Further, in the method for manufacturing a liquid crystal display device of the present invention, at least one of the substrates has a plurality of regions having mutually different surface free energies, and the surface free energy of the region of low surface free energy is 75 mN / m. Is less than
Alternatively, the surface energy difference between the plurality of regions is 15 mN /
By irradiating a mixture containing at least a liquid crystal material and a photopolymerizable material, which is injected between two substrates having a length of m or more, with ultraviolet rays, phase separation accompanying a polymerization reaction is caused, and a polymeric material is regularly formed. And a liquid crystal material are distributed, a method of manufacturing a liquid crystal display device.

The liquid crystal material and the polymer material may be phase-separated while applying at least one of a voltage and a magnetic field.

The photopolymerizable material may contain a liquid crystal polymerizable monomer.

The surface free energy of the photopolymerizable material may be 40 mN / m or less. The liquid crystal cell filled with the mixture between the two substrates is gradually cooled to a temperature equal to or higher than the homogenizing temperature (T _iso ) of the mixture of the liquid crystal material and the photopolymerizable material to T _iso or less, and the liquid crystal The photopolymerizable material may be cured after the material is deposited.

Further, in the method of manufacturing a liquid crystal display element of the present invention, a liquid crystal display element in which a display medium having a plurality of liquid crystal regions surrounded by polymer walls is provided between a pair of substrates which are opposed to each other. And a step of forming a thin film on at least a part of at least one of the substrates other than the picture element portion, and the pair of substrates are arranged so that the thin films are disposed inside and facing each other with a gap therebetween. A step of combining, a step of injecting a mixed material containing at least a liquid crystal material, a photopolymerizable material and a photopolymerization initiator into the gap, and a step of irradiating the mixed material with ultraviolet rays to form a plurality of walls surrounded by the polymer wall. And a step of forming a display medium composed of a liquid crystal region, whereby,
The above object is achieved.

When irradiating the mixed material with ultraviolet rays, the portion of the mixed material corresponding to the picture element portion is covered with a photomask, and the ultraviolet intensity of the portion covered with the photomask is
You may make it 80% or less of the intensity | strength of the ultraviolet-rays irradiated.

The liquid crystal material and the polymer material may be phase-separated while applying at least one of a voltage and a magnetic field.

The photopolymerizable material may contain a liquid crystal polymerizable monomer.

The surface free energy of the photopolymerizable material may be 40 mN / m or less. Further, in the method for manufacturing a liquid crystal display element of the present invention, at least one of the substrates has a plurality of regions having mutually different surface free energies, and the surface free energy of the low surface free energy region is 75 m.
By heating a mixture containing at least a liquid crystal material and a heat-polymerizable material, which is injected between two substrates having a surface energy difference of N / m or less or a surface energy difference of the plurality of regions of 15 mN / m or more, The polymer material and the liquid crystal material are regularly distributed by causing phase separation due to the polymerization reaction, thereby achieving the above object.

The liquid crystal material and the polymer material may be phase-separated while applying at least one of a voltage and a magnetic field.

The thermopolymerizable material may contain a liquid crystal polymerizable monomer.

The surface free energy of the thermopolymerizable material may be 40 mN / m or less. The liquid crystal cell filled with the mixture between the two substrates is gradually cooled to a temperature equal to or higher than the homogenizing temperature (T _iso ) of the mixture of the liquid crystal material and the thermopolymerizable material to T _iso or less, and the liquid crystal The thermopolymerizable material may be cured after the material is deposited.

Further, the method for producing a liquid crystal display element of the present invention is the method for producing a liquid crystal display element in which a liquid crystal material and a polymer material are sandwiched between a pair of substrates on which electrodes are formed and at least one of which is transparent. The interface of the substrate, which is in contact with the liquid crystal material and the composite film made of the polymer material, is selectively modified, thereby achieving the above object.

An alignment film may be formed at the interface of the substrate in contact with the composite film made of the liquid crystal material and the polymer material.

The alignment film may be subjected to a rubbing treatment, and the surface of the alignment film may be selectively modified by a rubbing strength difference caused by a height difference of the electrodes.

A coating may be formed on a specific region of the alignment film.

The method includes the steps of forming an alignment film on the substrate on which the electrodes are formed, forming a film on a specific region of the alignment film, and rubbing the alignment film and the film. But it is okay.

[0056]

According to the invention of claim 1, the liquid crystal display device comprises a pair of substrates, and a plurality of regions having mutually different surface free energies are formed in a regular pattern on at least one of the substrates. Has been done. The polymer wall formed by curing the polymerizable material sandwiched between the pair of substrates is formed on a part of a plurality of regions where the first surface free energy is defined. A plurality of liquid crystal regions sandwiched between the pair of substrates are formed on a plurality of other regions where the second surface free energy is determined and are substantially surrounded by the polymer wall. ing.

Here, the first surface free energy γ _p and the second surface free energy of the part of the plurality of regions, the other part of the plurality of regions, the polymer wall and the liquid crystal region are γ _E , the surface free energy γ _LC of the liquid crystal material, and the surface free energy γ _M of the polymerizable material are expressed by the relational expression (γ _E −γ _P ) × (γ _LC −γ _M )> 0 (1) Selected as a combination that meets your needs.

As a result, the second surface free energy γ
_E > first surface free energy γ _p , and surface free energy γ _LC of liquid crystal material> surface free energy γ _M of polymerizable material. Alternatively, the second surface free energy γ _E
<First surface free energy γ _p and surface free energy γ _LC of liquid crystal material <Surface free energy γ _M of polymerizable material. In any of the above two cases, the magnitude relation among the first surface free energy γ _p, the second surface free energy γ _E , the surface free energy γ _LC of the liquid crystal material, and the surface free energy γ _M of the polymerizable material is one of the two cases. Even so, the liquid crystal material is substantially formed in the plurality of regions of the one portion, and the polymer material is substantially formed in the plurality of regions of the other portion. Therefore, the liquid crystal material and the polymer material are clearly phase-separated.

According to the invention of claim 2, the liquid crystal display element 2
It comprises a number of electrode substrates, at least one of which is transparent. At this time, a wall made of a polymer material and a liquid crystal region in contact with the wall are provided between at least one of the electrode substrates. Regions having different surface free energies are regularly arranged on the at least one substrate, and polymer walls are formed substantially in the regions having low surface free energy. Also in this case, similarly to the invention of claim 1,
The liquid crystal material and the polymer wall are clearly phase-separated. Further, at least one of the electrode substrates is transparent, and therefore, in addition to the phase separation based on the surface free energy, a phase separation treatment such as irradiating the liquid crystal material and the polymer material with light is also performed. You can

According to the first aspect of the invention, in the liquid crystal display element, the cell gap d ₁ of the picture element region of at least one of the two electrode substrates and the cell gap d of at least a part other than the picture element region are two. ₂ may have a liquid crystal region in contact with a wall formed of a polymer material formed between the electrode substrates, which has a relationship of d ₁ > d ₂ . In this case, the surface free energy of each region having the cell gaps d ₁ and d ₂ and the surface free energy of the liquid crystal material are also formed by forming a plurality of regions having different cell gaps on the at least one electrode substrate. And the surface free energy of the polymer material can satisfy the relationship represented by the above formula (1). Therefore, also in the present invention, as described above, clear phase separation between the liquid crystal material and the polymer material can be achieved.

In the invention of claim 1, the cell gaps d ₁ and d ₂ are selected so as to satisfy the relationship 0.1 × d ₁ <d ₂ <0.9 × d ₁ (2) There is a case. Even in the liquid crystal display device in which the cell gaps d ₁ and d ₂ are selected as described above, the clear phase separation between the liquid crystal material and the polymer material is performed as described above.

In the invention of claim 5, the portion outside the picture element on the side of the substrate having the active element is a light-shielding area, and the counter substrate has at least a portion other than the picture element, which partially transmits ultraviolet rays. In this case, in addition to the phase separation by the cell gap, the light-shielding region and the region that partially transmits the ultraviolet light can be used to perform the phase separation by the ultraviolet irradiation together.

According to the sixth aspect of the present invention, the liquid crystal display element has a structure in which a display medium having a plurality of liquid crystal regions surrounded by polymer walls is provided between a pair of substrates which are arranged to face each other. Have At this time, a thin film is provided on part or all of the surface of the display medium side of at least one of the substrates except the picture element portion, and the value of the surface free energy other than the picture element portion is lower than the value of the surface free energy of the picture element portion. It has been made smaller.

Therefore, by providing the thin film, a plurality of regions having mutually different surface free energies can be provided on the surface of the substrate. This allows clear phase separation between the liquid crystal material and the polymer material.

According to a sixth aspect of the invention, the picture element of 70
% Is formed in a state where at least one liquid crystal region having a size of 30% or more of the area of the picture element is held in one picture element, the aperture ratio of the liquid crystal display element can be increased. Therefore, the brightness on the display can be increased.

According to the sixth aspect of the invention, even if the surface free energy in the region where the surface free energy is low is 75 mN / m or less, clear phase separation between the liquid crystal material and the polymer material as described above is performed. You can

In the invention of claim 6, when the surface energy difference between the low surface free energy region and the high surface free energy region is 15 mN / m or more, if the surface free energy difference is more than this value, As described above, clear phase separation between the liquid crystal material and the polymer material can be realized.

According to the tenth aspect of the invention, as means for controlling the spatial structure between the substrates at the time of producing the liquid crystal display element, the free energy of the system constituting the element is spatially adjusted at the time of producing the element or in advance. The control means is used. Therefore, clear phase separation between the liquid crystal material and the polymer material can be performed.

According to the invention of claim 11, as the spatial control of the free energy, the interface on the composite side of at least one substrate and at least one of the constituent components of the composite are provided.
When using the control of the interfacial free energy with the component, the at least one component may be aggregated in a predetermined region having a predetermined surface free energy. This makes it possible to clearly perform phase separation between the liquid crystal material and the polymer material.

In the invention of claim 11, in order to control the interfacial free energy, when a photosensitive resin is formed in a predetermined pattern on a substrate, the phase separation between the liquid crystal material and the polymer material is clearly and high. Can be done with precision.

In the eleventh aspect of the present invention, the phase separation between the liquid crystal material and the polymer material described above can be clearly performed even when surface modification is performed to control the interface free energy.

In the tenth aspect of the present invention, as a spatial control of free energy, the distance of the void between the two substrates is controlled so that the composite body has a controlled ordered structure at the time of device fabrication. The surface area of the phase separation interface of the constituent materials is
When the substrate is configured to be smaller than the surface area in the case of the disordered structure, when the composite constituent material shifts from the disordered structure to the controlled ordered structure as the phase separation proceeds, The surface area of the phase separation interface is gradually reduced. Therefore, also in such an invention, it is possible to perform a clear phase separation between the liquid crystal material and the polymer material as described above.

According to the fifteenth aspect of the present invention, at least one of the substrates has a low energy surface having a surface free energy of 75 mN / m or less, or a surface energy difference between the low energy region and the high energy region is 15 mN / m. By irradiating the mixture containing at least the liquid crystal material and the photopolymerizable material injected between the two substrates selected from the above with ultraviolet rays, phase separation caused by the polymerization reaction is caused to occur regularly. A polymer material and a liquid crystal material are distributed in the area.

According to the present invention, when the phase separation of the liquid crystal material and the polymer material is performed, the phase separation by the spatial control of the free energy can be performed together with the phase separation by the ultraviolet irradiation. The phase separation can be performed more clearly.

According to the twentieth aspect of the present invention, a thin film is formed on a part or the whole of at least one of the substrates other than the picture element part, and both substrates are opposed to each other with the thin film provided inside and a gap. Let it stick together. Further, a mixed material containing at least a liquid crystal material, a photopolymerizable material and a photopolymerization initiator is injected into the gap, and the mixed material is irradiated with ultraviolet rays to display a plurality of liquid crystal regions surrounded by polymer walls. Form the medium.

As a result, the surface free energy of the surface of each substrate can be controlled by the thin film formed in a predetermined pattern on at least one of the substrates, or the above-mentioned cell gap between the substrates can be controlled. it can.
Therefore, as described above, the phase separation using the control of the surface free energy can be performed together with the phase separation by irradiating the mixed material with ultraviolet rays, and the phase separation can be performed more clearly. .

In the twentieth aspect of the invention, when the mixed material is irradiated with ultraviolet rays, a portion of the mixed material corresponding to a picture element portion is covered with a photomask, and the ultraviolet intensity of the portion covered with the photomask is changed. , UV intensity of 80
When it is performed so as to be not more than%, the above-mentioned clear phase separation can be performed even by using the intensity unevenness of ultraviolet rays having such an intensity difference.

According to the invention of claim 25, at least one of the substrates has a low energy surface with a surface free energy of 7
It is 5 mN / m or less, or the surface energy difference between the low energy region and the high energy region is selected to be 15 mN / m or more. At least the liquid crystal material injected between the two substrates and the thermal polymerization property. The mixture containing the materials is heated to cause phase separation accompanying the polymerization reaction,
The polymer material and the liquid crystal material are regularly distributed. Thereby, in addition to the phase separation using the control of the surface free energy, the heating can further clarify the phase separation.

In the heat treatment, when the mixture of the liquid crystal material and the polymerizable material is equal to or higher than the homogenizing temperature (T _iso ) and equal to or lower than the homogenizing temperature T _iso , the liquid crystal material and the polymerizing property between the two substrates are increased. The liquid crystal cell filled with the mixture with the materials is gradually cooled.
As a result, the liquid crystal material is precipitated from the mixture of the two. After the deposition of the liquid crystal material, the polymerizable material is cured. As a result, the deposited liquid crystal material serves as a nucleus, and the phase separation between the liquid crystal material and the polymer material can be clearly performed.

In the inventions of claims 15, 20, and 25, when the liquid crystal material and the polymer material are phase-separated while applying a voltage or a magnetic field at the time of preparation, the liquid crystal molecules are applied by applying the voltage or the magnetic field. The phase separation can be performed with the directors aligned in the direction of the voltage or magnetic field.

In the inventions of claims 15, 20 and 25, the polymerizable material may contain a liquid crystal polymerizable monomer. This can further improve the clarity of the phase separation of the mixture.

In the inventions of claims 15, 20 and 25, the surface free energy of the polymerizable material is 40 mN / m.
In the case of the following, even in this case, phase separation can be performed by controlling the surface free energy described above.

According to the thirtieth aspect of the invention, the interface of the substrate in contact with the composite film made of the liquid crystal material and the polymer material is selectively modified. Therefore, by selectively modifying the interface of the substrate, it is possible to control the surface free energy of each region in the selectively modified region and the unmodified region. The phase separation between the polymer material and the polymer material can be clearly performed.

In the thirtieth aspect of the present invention, when an alignment film is formed at the interface of the substrate in contact with the composite film composed of the liquid crystal material and the polymer material, the alignment film is used to selectively control the surface free energy. It can be used as a means to do.
Accordingly, also in the present invention, phase separation between the liquid crystal material and the polymer material can be performed by controlling the surface free energy.

In the thirtieth aspect of the invention, when the alignment film is subjected to rubbing treatment and the surface of the alignment film is selectively modified by the rubbing strength difference caused by the height difference of the transparent electrode, such alignment is performed. By selectively changing the rubbing strength with respect to the film, the phase separation can be clearly performed by controlling the surface free energy.

According to the thirty-first aspect of the invention, when a film is formed on a specific region of the alignment film, the film can be used as a means for selectively controlling the surface free energy.

According to a thirtieth aspect of the invention, a step of forming an alignment film on the substrate having the electrodes formed thereon, a step of forming a film on a specific region of the alignment film, and rubbing the alignment film and the film. In the case of including a treatment step, the coating can be used as a means for controlling the surface free energy, and the rubbing strength can be selectively changed when the rubbing treatment is performed on the coating. Phase separation by controlling the intensity can also be used together.

In order to improve the contrast in a liquid crystal display device having a liquid crystal region surrounded by a polymer wall,
Minimize the interface between liquid crystal material and polymer material,
Moreover, it is preferable that at least one liquid crystal region exists in one picture element. Therefore, it is necessary to control the arrangement and size of the liquid crystal region. Particularly, in order to prevent display contrast reduction due to scattering at the interface between the liquid crystal material and the polymer material in a pixel, 70% or more of the pixel is 30% of the size of the pixel in one pixel. One liquid crystal area of the above size
It is desirable to control the state to have one or more.

In the liquid crystal region surrounded by such a polymer wall, a mixed material containing a polymerizable material and a liquid crystal material is injected into a pair of substrate gaps (cells), and the polymerizable material is polymerized to cause a liquid crystal material. It is obtained by carrying out phase separation with. In order to limit the position where this polymerization reaction occurs, for example, as shown below, a method of forming a place where the polymerizable material and the liquid crystal material are easily arranged in the cell can be considered.

(1) A place where the polymerizable material is easily collected is provided. For example, a thin film that improves the wettability of the polymerizable material is formed in a portion other than the picture element portion of at least one of the pair of substrates that are opposed to each other. As a result, the polymerizable material is more likely to collect in the portion other than the pixel portion than in the pixel portion, and the polymerization reaction can proceed in the portion other than the pixel portion. In this case, it is preferable that (surface free energy of polymerizable material) ≈ (surface free energy of thin film) <(surface free energy of liquid crystal material). When such a relationship is established, the liquid crystal region is targeted. It is possible to create it at the position.

(2) Provide a place where the liquid crystal material is easily collected. For example, a thin film that improves the wettability of liquid crystal is formed on at least one of the picture element portions of the substrate. This makes it easier for the liquid crystal material to collect in the picture element portion.

(3) A place where the polymerizable material is easily collected and a place where the liquid crystal material is easily collected are provided. For example, a thin film for improving the wettability of liquid crystal is formed on the picture element portion of at least one of the substrates, and a thin film for improving the wettability of the polymerizable material is formed on the portion other than the picture element portion. As a result, a liquid crystal region is easily formed in the picture element portion, and a polymer region is easily formed in a portion other than the picture element portion, so that each region can be clarified.

Among the above (1) to (3), forming a thin film having liquid crystal wettability better than ITO as in (2) is not very practical except when forming a metal thin film. Since it is not used as a reflection type, (1) a method of forming a thin film that improves the wettability of the polymerizable material on a portion other than the pixel portion is most suitable. Since an electrode made of ITO (a mixture of indium oxide and tin oxide) is usually formed in the pixel portion, the surface free energy of the thin film formed in the case of (1) is higher than the surface free energy of ITO. Is also preferably small. Further, in order to make the surface free energy of the pixel portion (ITO) and the surface other than the pixel portion largely different, the surface free energy of the thin film is preferably 40 mN / m or less.

Further, when performing the ultraviolet irradiation, a photomask is formed so as to cover the portion corresponding to the picture element of the above-mentioned mixed material, and the ultraviolet intensity applied to the portion covered with the photomask is adjusted to the other portion. It can be 80% or less. The photopolymerization reaction speed is high in the portion other than the pixel portion where the ultraviolet intensity is strong, and the phase separation speed between the liquid crystal material and the polymer material is also high, so that the polymer material is formed quickly. On the other hand, the photopolymerization reaction rate is slow in the pixel portion where the UV intensity is weak. Therefore, the liquid crystal material is pushed out to the picture element portion, and a liquid crystal region is generated in the picture element portion.
As described above, the use of the photomask makes it possible to further clarify the phase separation.

Further, by forming a polarizing plate on the side opposite to the display medium of the pair of substrates, the conventional TN, ST
A liquid crystal display element using N, FLC (SSF) or ECB mode can be used.

The inventors of the present invention focused on the fact that a polymer material or a liquid crystal material has different affinities in regions having different surface free energies or different cell gaps on a substrate, and thus a novel method for patterning a polymer wall was proposed. developed. Further, in an element having a liquid crystal region surrounded by a polymer material obtained by curing a polymerizable material, liquid crystal molecules are arranged axially symmetrically (including radially) in the liquid crystal region, and substantially monodomain ( It was also found that the contrast can be improved by producing a liquid crystal display device having several domains).
Hereinafter, the present invention will be described in more detail with reference to Examples.

[0097]

EXAMPLE An outline of an example of the present invention will be described below.

(Necessity of Control of Liquid Crystal Region and Polymer Region (Wall)) When an image is displayed by the dot matrix method, each pixel becomes a pixel and the portion related to the display is regularly arranged and Configure the image with. In a liquid crystal display device,
This is realized by a driving method such as a simple matrix method or an active matrix method.

In the liquid crystal display element of the present invention,
A composite film of a polymer material and a liquid crystal material is used as a display medium. By sandwiching this composite film between polarizing plates, the optical rotation and birefringence of the liquid crystal region are controlled by an electric field to create a light transmitting state and a light blocking state. At this time, the polymer region is optically isotropic and its optical characteristics do not change depending on the applied electric field used for display. Therefore, the contrast, which is the ratio of the transmittance in the transmission state and the transmittance in the blocking state, which is an index of the visibility in the display. In order to obtain a sufficient value for the ratio, the polarizing plates to be attached on the substrate should be arranged so that their transmission axes are orthogonal to each other. However, even in this arrangement of the polarizing plate, if the liquid crystal regions are not sufficiently aligned, the transmittance becomes uneven and the roughness is caused.

As a means for suppressing the variation in the transmittance of each picture element, the number of liquid crystal regions included in each picture element is increased so that the variation in the optical characteristics of each liquid crystal area causes the characteristic of the picture element. There is a way to prevent it from being reflected in. However, in this method, the polymer material is inevitably formed in the picture element, so that the transmittance is lowered. As for the transmittance of the entire display element, it is desirable that the liquid crystal region of each picture element is concentrated more than the non-picture element portion, and more preferably, each picture element is occupied by a single liquid crystal region. .

In this way, it is important to sufficiently control the position where the liquid crystal region is formed and the shape thereof in the pixel region so as to secure a sufficient transmittance and avoid the roughness.

(Production of Device Utilizing Control of Free Energy) The present invention proposes a method of controlling free energy as a method of controlling the positions of the liquid crystal region and the polymer region in this composite film. Under control of this free energy,
By causing phase separation from the state where the mixture is in a single phase, forming two phases separated into the target position and shape, and fixing them, the position and shape of the target liquid crystal region and polymer region Control is realized.

In the process of manufacturing the device, in order to separate the liquid crystal region and the polymer region from each other, the temperature of the mixture of the liquid crystal material and the polymerizable material (prepolymer) is gradually changed from that in a single phase. There is a method of causing phase separation by lowering and fixing the separated state. In the present invention, the difference in the physical and chemical properties of the two phases having different fluidity at the stage of phase separation, or the property of the interface forming the boundary between the two phases is utilized. By controlling the position and shape of each phase, the position and shape of the liquid crystal region and the polymer region in the produced composite film can be controlled.

This is a very effective method in controlling the positions of the liquid crystal region and the polymer region, as compared with the above conventional technique. This is because in this method, the magnitude of the reaction rate in the polymerization of the prepolymer does not significantly affect the positions and shapes of the liquid crystal region and the polymer region in this liquid crystal display device.

(Type of Controllable Free Energy) Free energy that can be controlled with required accuracy inside the substrate of the liquid crystal display element is suitable for the present invention. The controllable free energy includes interface free energy, electric field energy, static magnetic field energy, and the like.

(Mechanism of Control of Phase Separation by Controlling Free Energy) In the present invention, basically, not the phase separation utilizing the polymerization of the polymerizable material as in the conventional method but the heat caused by the temperature control is used. Use phase separation. Therefore, in the process of phase separation,
The behavior of the system is described by thermodynamics. In the actual manufacturing process of the liquid crystal display element, it can be considered that the substance does not substantially enter and leave and the heat capacity of the substrate is sufficiently larger than the heat capacity of the composite film including the liquid crystal material and the polymer material. it can. Furthermore, compared to the time scale at which phase separation occurs, the time for liquid crystal molecules or prepolymer molecules to travel a distance equivalent to the size of the picture element of the display element due to thermal motion is sufficiently short, and the composite film is essentially a system in thermal equilibrium. Can be considered as. The behavior of such a thermodynamic system, which is closed and in thermal equilibrium, is usually described using free energy.

Generally, free energy of Helmholtz and free energy of Gibbs are used as the free energy in the case of a constant volume and a constant pressure, respectively. These divisions are necessary when the work of pressure from outside the system with respect to the free energy that governs the system needs to be considered under the condition of constant pressure, as compared to the condition of constant volume ( If the gas is in contact with the system). Regarding the liquid crystal display element to be considered now, under the condition that the voids supported by spacers between substrates that are almost rigid are close to a certain volume, and only the condensed phase such as liquid phase (isotropic phase) or liquid crystal phase is used. The division of the free energy is not necessary, since the phase separation behavior of the constituent mixture is discussed.

It will be described below that the position and shape of the liquid crystal region and the polymer region can be artificially controlled by controlling this free energy.

In the manufacturing process of a liquid crystal display element, a mixture of a liquid crystal material and a prepolymer is injected into two substrates at a temperature such that an isotropic phase is obtained, and then slowly cooled to separate the isotropic phase and the liquid crystal phase. , Including the process of using means for fixing this. In such a manufacturing process, when phase separation between a liquid crystal phase and an isotropic phase is occurring, the free energy is controlled for at least one of the two phases or the interface between the phases to achieve this phase separation. It is possible to control the free energy of the entire system related to the above so as to be the minimum when the desired arrangement and shape of the liquid crystal region and the polymer region are achieved. The arrangement and shape of the liquid crystal regions that are actually realized under this control become closer to the object as compared with the case where this control is not performed.

Further, by spatially and selectively patterning the control of the free energy with respect to at least one of the phases or the interface of the phase, the phase arrangement conforming to this pattern is realized.

(Specific Control of Free Energy and Mechanism Thereof) Here, a control mechanism of the liquid crystal region when a more specific control method of free energy is used will be described.

(1) (Phase Separation Method by Controlling Interface Free Energy) A material having different interface free energies for a liquid crystal phase and an isotropic phase is applied to a substrate in advance, and this material is patterned. A liquid crystal phase can be arranged. This is due to the interfacial free energy for the liquid crystal phase on the substrate where this material is placed, the interfacial free energy for the isotropic phase, and the liquid crystal phase and isotropic for the portion on the substrate where this material is not placed. It can be controlled by appropriately setting the relationship among the four types of interfacial free energy with respect to the phase as described later. By fixing the liquid crystal region thus arranged, the liquid crystal region can be controlled to a desired position / shape. Hereinafter, this phase separation method will be described in detail.

(A) (Phase Separation Method of Liquid Crystal Material and Polymer Material) The present invention relates to a liquid crystal material and a polymer material by polymerizing the polymerizable material in a uniform mixture of the liquid crystal material and the polymerizable material. When phase separation is performed, two types of regions having different surface free energies or different cell gaps are patterned and formed on the substrate, so that the affinity of the polymer material and the liquid crystal material are mutually different in the two types of regions. It includes a method of performing phase separation between a liquid crystal material and a polymer material by utilizing the difference.

FIG. 10 shows a typical example of the liquid crystal cell used in the present invention. 10A is a sectional view of the liquid crystal cell, and FIG. 10B is a plan view of the liquid crystal cell. The liquid crystal cell of the present invention includes a pair of substrates 1 and 2 and electrodes 3 and 4 formed on surfaces of the substrates 1 and 2 facing each other. At least one of the pair of substrates 1 and 2
A convex portion 16 made of a polymer material or an inorganic material is formed outside the picture element region, and the picture element region portion is formed by the convex portion 16.
The structure is substantially surrounded by. To the liquid crystal cell, ultraviolet light (in the case of an ultraviolet polymerizable material) or heat (in the case of a heat polymerizable material) is added to a mixture of a liquid crystal material and a polymerizable material to polymerize the polymerizable material to increase the liquid crystal material Allows phase separation of molecular materials.

In the present invention, when the resin polymerization rate is sufficiently slower than the resin migration rate, the liquid crystal molecules partially phase-separated have a higher affinity because the surface having different affinity for the liquid crystal material exists on the substrate 1. Collect in one area and extrude the polymerizable material into the other area. Alternatively, in the region where the cell gap is small, the polymer wall can be formed with a small amount of the polymerizable material, so that the polymerizable material gathers in the patterned region where the cell gap is small. Therefore, in the present invention, the polymer wall 8 is formed along the patterned region in the substrates 1 and 2, and the liquid crystal region 7 can be clearly separated into the other region.

In this case, when the phase separation is performed, the formation of a region in which the liquid crystal material and the polymer material are mixed by the conventional method between the liquid crystal region in the liquid crystal region and the substrate material is suppressed, and the voltage is saturated. It is possible to prevent light leakage of birefringent light due to liquid crystal molecules trapped in the polymer wall.

According to this method, the effect of the present invention can be sufficiently obtained even if only one of the substrates having the regions having different surface free energies patterned is used and the substrate is used in the combination of the patterned substrate and the non-patterned substrate. . Further, the effect of the present invention can be sufficiently obtained by forming both substrates into cells using patterned substrates. Furthermore, when both substrates are made into cells with patterned substrates, the shapes of the patterns on both substrates do not necessarily have to be the same.
It is possible to create a liquid crystal display device in which polymer walls are formed in a lattice pattern by using cells in which regions of different surface free energies are formed in stripes on both substrates and the patterns of both substrates are orthogonal to each other. it can.

(B) (Relationship between Surface Free Energy) The present invention is a method for regularly separating a liquid crystal material and a polymer material by the difference in surface free energy, and the surface free energy between the liquid crystal material and the curable monomer. Of the surface free energy between the substrate and the pattern region is important.

I) (Surface free energy of liquid crystal material γ _LC
> Case of Surface Free Energy γ _M of Polymerizable Material In this case, as shown in FIG. 11A, the surface of at least a part of the convex portion 16 other than the pixel region is made to have a low surface free energy. As shown in FIG. 11B, it is possible to form the polymer wall 8 on a portion other than the picture element.

By adding a polymerizable monomer having an F (fluorine) atom to the polymerizable material in the polymerizable material composition, the surface free energy of the polymerizable material is lowered, and the effect of the present invention is more remarkably exhibited. More preferable. Furthermore, in this case, since the compatibility between the polymerizable monomer having an F atom and the liquid crystal material is generally low, the separation of the liquid crystal monomer after the phase separation is good, and the liquid crystal monomer in the polymer wall is separated. The amount of dissolution decreases. For this reason, the amount of liquid crystal molecules existing in the polymer material existing at the interface between the liquid crystal material and the substrate in the liquid crystal region is reduced, and it does not respond to the electric field when the saturation voltage is applied as described in the section of the prior art. The amount of liquid crystal molecules is reduced, and the display contrast is improved. Furthermore, when a polymerizable monomer having an F atom is present, the F atom is unevenly distributed at the interface between the liquid crystal material and the polymer material, so that the anchoring strength of the liquid crystal material and the polymer material is reduced, and the driving voltage is reduced. Has the effect of lowering.

It is preferable to use a polymer material containing an F atom as a material to be used in a patterned region in a portion other than the picture element on the substrate, since the surface free energy can be extremely lowered.

The effect of the present invention can also be obtained by forming a thin film having a high surface free energy on the pixel portion.

Ii) (Surface free energy γ of liquid crystal material)
_LC <Case of Surface Free Energy of Polymerizable Material γ _M ) In this case, as shown in FIG. 12A, in at least a part of the pixel region, the surface free energy is lower than the region other than the pixel region. By forming the portion using the convex portion 16, it is possible to form the polymer wall 8 on the portion other than the picture element.

As described above, according to the present invention, the surface free energy γ _LC of the liquid crystal material and the surface free energy γ _M of the polymerizable material are
In the case of both i) and ii) regarding the magnitude relationship with, the effect of forming a pattern having different surface free energy on one substrate 1 and confining the liquid crystal material in a certain region due to the difference in surface free energy. Is intended. At this time, it is more preferable to pattern regions having different surface free energies on both substrates 1 and 2 because the above effect is promoted. In this case, the patterns of the regions having different surface free energies on both substrates 1 and 2 do not have to be the same and may be different. For example, in a simple matrix driving cell, stripe-shaped regions having different surface free energies may be created and combined so that the patterns of the regions on the upper and lower substrates 1 and 2 are orthogonal to each other. .

(2) (Method of Surface Modification) This method of controlling the surface free energy can be realized by selectively modifying the surface of the substrate instead of the method using the above material. The liquid crystal display element of the present invention is characterized in that the surface of the alignment film is selectively modified by a rubbing treatment to separate the polymer material and the liquid crystal material into phases, and the respective materials are unevenly distributed. Specifically, a step is regularly formed by electrodes and thin films, a method by rubbing treatment of the bristles of the rubbing cloth, a thin film such as a resist is further formed at a specific position on the surface of the alignment film, and then the rubbing treatment is performed. There is a method of doing. By using these methods, it is possible to modify the surface of the alignment film between the electrode portion and the non-electrode portion by rubbing. By carrying out such modification, the alignment film surface can be selectively provided with optical anisotropy, the cell gap obtained from the steps of the electrodes or the alignment film, or the rubbing strength of the alignment film surface. It is also possible to control the rate of monomer polymerization, the mobility of the liquid crystal material and the mobility of the polymer material that accompany polymerization due to the different roughness. By combining such actions, the phase separation between the liquid crystal material and the polymer material can be clearly performed, and the polymer wall can be patterned.

As specific means therefor, there are a rubbing method, a glow discharge method, a chemical treatment method such as etching, and an irradiation method with electromagnetic waves and radiation. The rubbing method has been conventionally used as a means for aligning liquid crystal molecules in a specific direction. Here, it is utilized that the surface free energy of the liquid crystal molecules with respect to the substrate changes according to the rubbing intensity due to the rubbing.

Rubbing rubs the substrate in a particular direction and utilizes the surface modification caused by this mechanical friction. Therefore, the surface free energy can be controlled by selectively changing the rubbing strength depending on the position on the substrate. The strength of this rubbing can be controlled by the pressure, speed, number of times, etc. in the above mechanical friction, but the control force on the scale of the size of a picture element requires an alignment film formed by patterning a photosensitive resin or the like. Is used to selectively weaken the rubbing strength by protecting the surface, or to provide unevenness on the surface itself such as an alignment film to be rubbed in advance and selectively control the rubbing strength with respect to the position by this unevenness, or used when rubbing There is a method of patterning with a friction material.

Further, by the method such as glow discharge, etching, irradiation of electromagnetic waves or radiation, the selection of the position of the size of a picture element related to the rubbing strength can be realized.

When two cells are bonded together to form a cell and phase separation is caused after injection of a mixture of a liquid crystal material and a polymerizable material, the surface free energy of the liquid crystal phase is increased as described above. The liquid crystal phase concentrates in the lowered region. Therefore, the liquid crystal region can be arranged in a desired position and shape.

(3) (Method of Applying Electric Field) Further, as an example of an external field, phase separation is caused in a state where an electric field is applied, and the difference in dielectric constant between the liquid crystal phase and the isotropic phase is used to change the dielectric constant. Large liquid crystal phases can be collected under the electrodes. This is because when an electric field is applied to a substance having a large dielectric constant, the electric flux density generated therein and the electric field energy accumulated in the space due to the electric field change the free energy. At this time, it is necessary to consider the work done by the power source in the discussion on thermodynamic equilibrium. The energy lost by the power source due to the outflow of electric charges from the power source due to the applied voltage is exactly twice the electric field energy stored in this space, and the free energy of the entire system including the power source is the electric field stored in the space. It is reduced by the amount of energy, which is eventually dissipated in the form of heat. Therefore, the larger the permittivity of the substance existing in the space to which the electric field is applied by the power source, the lower the free energy of the entire system, and the equilibrium of the system changes in the direction of decreasing the energy.

That is, when the dielectric constant of the liquid crystal phase is larger than that of the isotropic phase, and when there are regions where the electric field is applied and regions where the electric field is not applied, the electric field is not applied. The liquid crystal phase is distributed in the existing area and the isotropic phase is distributed in the non-applied area. By fixing this distribution, the liquid crystal region can be concentrated under the electric field. When this voltage is applied using the display electrode, it is convenient because not only the liquid crystal material necessary for display is collected under the display electrode, but also the shape of the liquid crystal region matches the shape of the electrode.

(4) (Method of applying magnetic field) It goes without saying that the control of the formation of the liquid crystal region by the external field can be realized not by the electric field but by the magnetic field. In this case, the difference in magnetic permeability between the liquid crystal phase and the isotropic phase is used. The basic mechanism is the same as in the case of an electric field, but unlike the case of patterning by an electrode used when applying an electric field, patterning is performed in a cell in which the mixed material has been injected and has a high magnetic permeability and It can be realized by sandwiching between substrates having magnetic permeability and applying a magnetic field from the outside.

(5) (Method of controlling voids) There is also a method of controlling the voids between the two substrates used for the display element. As this method, before bonding these substrates, at least one of the surfaces of the two substrates on which the composite film of the liquid crystal material and the polymer material is formed is made uneven by using a photosensitive resin or the like. It is possible to bond two substrates after forming the substrate. In this method, there are regions with large and small voids between the substrates. Interface free energy that reduces the area of the interface acts on the interface between the two phases that have been phase-separated, so that the interface is arranged to be as small as possible. this is,
This is because the free energy of the interface is generated by the generation of the interface due to the phase separation, and the equilibrium of the system is moved so that the increment of the free energy due to this is minimized.

In the present invention, since the liquid crystal region is arranged so as to be surrounded by the polymer material, the liquid crystal phase is surrounded by this interface. Therefore, the liquid crystal phase and the isotropic phase after the phase separation are arranged such that the area of the interface between the two phases is small under the condition that the respective volumes are substantially constant, that is, the liquid crystal phase is arranged in a portion having a larger void, The isotropic phase is arranged in a narrow space.

As described above, the surface free energy on the substrate can confine the phase-separated liquid crystal material in a certain region, but when the mixing ratio of the liquid crystal material and the polymerizable material is biased to the liquid crystal material, In some cases, liquid crystal regions corresponding to adjacent picture elements are combined and a large liquid crystal domain is partially formed, which may cause roughness of display.
In the present invention, a liquid crystal display device having uniform display characteristics is produced by achieving the separation of the liquid crystal material and the polymer material in each of the regular patterns. Therefore, it is preferable to use a method other than the difference in surface free energy in order to control the movement of the substance.

As a method of controlling the movement of substances other than the difference in surface free energy, there is a method of making the cell gap of the region where the liquid crystal material is deposited larger than the cell gap of the region where the polymer wall is formed. In this case, the cell gap d ₁ of the picture element region at the time of device production and the cell gap d ₂ (minimum value) of at least a part other than the picture element region are 0.1 × d ₁ ≦ d ₂ ≦ 0.9 It is preferable to satisfy the relationship of xd ₁ (3). That is, when the cell gap d ₂ is smaller than 0.1 × d ₁ , the vacuum injection time into the cell becomes long, and the cell gap d
_{When 2} is larger than the cell gap of 0.9 × d ₁ , the effect of clarifying the separation between the liquid crystal material and the polymer material in the cell gap decreases.

(6) (Method of polymerizing at a temperature _{equal to} or higher than the compatibilizing temperature T _NI of the liquid crystal material and then gradually cooling) As a method for producing the liquid crystal display element of the present invention, a mixture of a liquid crystal material and a polymerizable material is used. After injecting a region having a surface free energy difference into a patterned cell, the liquid crystal material is separated from the polymer material by polymerizing at a temperature _{equal to} or higher than the compatibilization temperature T _NI point of the liquid crystal material and then gradually cooling. be able to. When a photopolymerizable material is used, the ultraviolet intensity is 50 mW / cm ² because the mass transfer between the liquid crystal material and the polymerizable material can be performed smoothly by lengthening the polymerization reaction time.
(Measured at a wavelength of 365 nm) or less, preferably 10 mW
/ Cm ² or less is preferable. Moreover, in order to carry out the polymerization reaction uniformly in the cell plane, it is preferable that the parallelism of the light source is poor.

The combination of the liquid crystal material and the polymerizable material is preferably such that the compatibilizing temperature of both is 30 to 120 ° C. For combinations with compatibilization temperatures below 30 ° C,
The degree to which the polymerizable material is mixed in the liquid crystal region after the phase separation or the liquid crystal material is mixed to the polymer wall becomes large.
The former leads to a decrease in response speed and a decrease in transmittance due to a decrease in retardation d · Δn when the voltage is turned off. In the latter case, a layer containing a liquid crystal material that does not respond to the voltage is formed, so that a voltage is applied. Black level is reduced.
On the other hand, if the compatibilizing temperature is 120 ° C. or higher, the processing temperature in the manufacturing process becomes high, and reactions such as decomposition and polymerization of the material are likely to occur, which is not preferable.

(7) (Method of thermally phase-separating and then ultraviolet curing) In order to improve the phase-separated state, the following method is preferable. Before inducing phase separation in the polymerization reaction, the mixture of the liquid crystal material and the polymerizable material is gradually cooled from a temperature equal to or higher than the homogenization temperature to a temperature equal to or lower than the homogenization temperature. By this slow cooling,
The mixture is thermally phase-separated, and a liquid crystal-rich region in which the ratio of the liquid crystal material is high in the ratio of the liquid crystal material and the polymerizable material, and a region in which the polymerizable material is high in the ratio of the polymerizable material is high in the ratio. And form. In this way, by increasing the concentration of the polymerizable material in advance and then causing the polymerization reaction, phase separation can be clearly performed. In this case, the higher the mixing energy of the liquid crystal material and the polymerizable material thermally, that is, the harder they are to mix, the more clearly the liquid crystal material and the polymerizable material can be separated, and the above problems are less likely to occur.

(8) (Combination of a plurality of methods) The several methods described in (1) to (7) above may be used in combination at the same time. At this time, it goes without saying that it is appropriate to combine the means for controlling the free energy in such a direction as to achieve the desired arrangement of the liquid crystal regions.

As an example of the combination, a photosensitive resin having a small surface free energy with respect to a liquid crystal phase is patterned on a substrate having an electrode structure in which a voltage is applied only to the region of the pixel, to form the pixel. Place it in a position other than the area. The two substrates thus configured are bonded together via a spacer. After injecting the mixture into the cell obtained by pasting and causing phase separation while applying voltage to the pixel electrode of the cell, triple control of control of interfacial free energy, electric field, and substrate void is performed. It will be given. This enables more reliable control of the position and shape of the liquid crystal region.

(Method of Fixing Controlled Shape of Liquid Crystal Region) It is necessary to fix this state after arranging the phases in a controlled and desired shape. Therefore, there is a method of polymerizing an isotropic phase prepolymer to obtain a polymer material. Two
When a mixture of liquid crystal material and prepolymer injected at a temperature to form a single isotropic phase between the substrates is gradually cooled to cause phase separation into two phases, a liquid crystal phase and an isotropic phase, The prepolymer fractions in the two phases are different and the isotropic phase is higher than the liquid crystal phase. Therefore, since the reaction rate on the isotropic phase side is high when the polymerization is started, it is possible to form the polymer wall not on the pixel portion related to display but on the portion other than the pixel. As a method for initiating this polymerization, a method in which the temperature of the device does not change greatly is desirable.

As described above, it is understood that the desired arrangement of the liquid crystal regions is realized by controlling the free energy.

The characteristics of the liquid crystal material in the phase-separated liquid crystal region and various materials used in the present invention will be described below.

(1) (Alignment State of Liquid Crystal Molecules in Domain) The liquid crystal domain in the liquid crystal display device of the present invention can be applied to two types.

(A) When the orientation regulating force on the substrate is not used FIG. 13 (a) is a conceptual diagram of a pixel area observed with a polarization microscope when the voltage is off, and FIG. 13 (b) shows a picture with the voltage on. It is a conceptual diagram by a polarization microscope observation of an elementary region. This FIG.
As shown in the conceptual diagram of observation by a polarization microscope, the liquid crystal region 7 surrounded by the polymer wall 8 is composed of one liquid crystal domain when the voltage is off, and in this liquid crystal domain, a cross is formed in the polarization axis direction of the polarizing plate. The extinction pattern 17 is observed. This means that the liquid crystal molecules are arranged in axial symmetry around the disclination point in the center of the pixel area. In the liquid crystal domain having such an arrangement, as shown in FIG.
As shown in FIG. 3B, the disclination line 15 is formed around the domain when a voltage is applied, and is not formed inside. Therefore, the disclination line 15 can be intentionally formed outside the display area of the picture element, and the disclination line 15 is normally formed around the display area on the substrate in order to prevent light leakage. By forming it below, the black level of the liquid crystal display device is improved and the contrast is improved.

When a voltage is applied to the liquid crystal display element having such an arrangement, the liquid crystal molecules rise in the direction perpendicular to the cell. At this time, the rise of the liquid crystal molecules occurs in an axially symmetrical manner which is the initial alignment (when the voltage is off), and the apparent refractive index is homogenized in all directions, so that the viewing angle characteristics are improved.

(B) Utilizing Orientation Controlling Force on Substrate By applying the method of the present invention using a substrate on which an alignment film on the substrate has been subjected to rubbing or the like, the polymer wall is substantially It is possible to create a liquid crystal display device which is surrounded and in which liquid crystal molecules are aligned along the alignment regulating force on the substrate.
These display modes are TN, STN, FLC, E
A mode generally used as a liquid crystal display device such as a CB mode can be applied. In this case, compared with a conventional display element having no polymer wall in the display area, the cell thickness has less variation with respect to external pressure, and the display characteristics have less variation.

(2) (Number of Domains in Picture Element) It is preferable that the number of domains in a picture element is as small as possible. When a large number of domains exist in one picture element, a disclination line is formed between the domains to lower the black level. It is preferable that the pixel portion is covered with a single domain in which liquid crystal molecules are arranged axially symmetrically within the domain. In this case, since the disclination line is formed on the outer periphery of the domain when the voltage is applied, the disclination line hardly enters the pixel portion. Further, when the device of the present invention is manufactured by a liquid crystal display device having a rectangular picture element region 18 as shown in FIG. 14, at least two single domains in which liquid crystal molecules are arranged in axial symmetry within the domain are formed. It is possible to use the elements that collectively form the liquid crystal region 7. The device has excellent viewing angle characteristics similar to the monodomain cell. Furthermore, the cross-shaped extinction pattern 17 formed in the picture element region 18 is aligned with the vertical and horizontal directions in FIG. 13 with the respective polarization axes of the pair of polarizing plates, so that the extinction pattern 17 can be seen when a voltage is applied. Can be hardened.

(3) (Method of not generating disclination line) Polymerizable material having a molecular skeleton similar to the mesogen group of the liquid crystal molecules exemplified below (hereinafter referred to as liquid crystalline polymer material) It is possible to prevent the occurrence of disclination lines by adding.

(A) Monofunctional Liquid Crystalline Polymerizable Material A molecule having one polymerizable group in the molecule, and by adding this molecule to the system, pretilt can be generated in the liquid crystal region. This pretilt results in an alignment state in which no disclination line is generated.
The reason why the disclination line does not occur is as follows. In a cell where a disclination line is generated around the liquid crystal region when a voltage is applied, the rise direction of liquid crystal molecules is different between the vicinity of the polymer wall and inside the liquid crystal region, resulting in a reverse tilt and a disclination line. It is presumed that the disclination line does not occur because the location is the same up to the wall.

(B) In the case of bifunctional liquid crystalline polymer material: A molecule having two polymerizable groups in the molecule, which has the effect of keeping the orientation of the liquid crystal material horizontal to the substrate and applying a voltage or magnetic field. However, by polymerizing the polymerizable material, it is possible to realize a structure in which no disclination line is generated. When a cell prepared using this material is observed with a polarizing microscope, a blackened region 19 exists near the polymer wall 8 as shown in FIG. This region 19 is presumed to be a region in which the twisted structure of liquid crystal molecules does not exist, and it is presumed that the liquid crystal molecules are twisted to the right and left at the boundary of this region.

(4) (Method of Aligning Liquid Crystal Molecules Axially Symmetrically) In order to align liquid crystal molecules axially symmetrically, the director of the liquid crystal material is changed in the process of phase separation of the liquid crystal material and the polymer material. It is preferable to apply an external force that aligns in one direction (perpendicular to the cell). When this external force is applied, the liquid crystal molecules are oriented in axial symmetry as can be understood from the cross extinction pattern shown in the conceptual diagram based on the polarization micrograph of FIG. 14 when observed from the direction perpendicular to the cell. Like

In order to arrange the directors of the liquid crystal molecules, it is preferable to apply an electric field, a magnetic field, or both to the liquid crystal molecules. In a liquid crystal display device, it is more preferable to use an electric field because there are electrodes for applying a voltage to liquid crystal molecules. The strength of the applied external field may be such that the directors of the liquid crystal molecules are aligned.

(5) (Polymerizable Material) The polymer material used is a thermopolymerizable material or a photopolymerizable material. Examples of the photopolymerizable material include acrylic acid and acrylic acid ester having a C3 or longer long-chain alkyl group or a benzene ring, and more specifically, isobutyl acrylate, stearyl acrylate, lauryl acrylate, isoamyl acrylate, n-Butyl methacrylate, n-lauryl methacrylate, tridecyl methacrylate, 2-ethylhexyl acrylate, n-stearyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, 2-phenoxyethyl methacrylate, isobornyl acrylate, isobornyl methacrylate and polymer physics. To increase the mechanical strength, a polyfunctional compound having two or more functional groups, for example, bisphenol A dimethacrylate, bisphenol A diacrylate, 1,4-butanediol Methacrylate,
1,6-hexanediol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, neopentyl diacrylate.

Furthermore, the effect of preventing liquid crystal molecules from being mixed into the polymer material after phase separation and the display characteristics relating to the anchoring strength of the polymer material surface such as driving voltage and hysteresis are improved as described above. In order to prevent scattering when a voltage is applied, it is necessary as a low refractive index material to match the refractive index of the ordinary light and the refractive index of the polymer material, and to match the refractive index of the liquid crystal material and the refractive index of the polymerizable material. Halogenated, especially chlorinated, and fluorinated photopolymerizable materials, such as 2.2.3.3.4.4-hexafluorobutyl methacrylate, 2.2.3.4.4.4-hexachlorobutyl methacrylate, 2.2.3.3-Tetrafluoropropyl methacrylate, 2.2.3.3-Tetrachloropropyl methacrylate, Perfluorooctylethyl methacrylate, Per Rollo octyl methacrylate, perfluorooctyl ethyl acrylate, perchloropentyl acrylate.

As the heat-polymerizable material, it is possible to use it by mixing the above-mentioned photopolymerizable material with a heat-polymerization initiator, and it is also possible to use a compound having an epoxy group in the molecule. Specifically, for example, bisphenol A type epoxy compound, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, hexahydrobisphenol A diglycidyl ether, poropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, diphthalic acid phthalate. Glycidyl ester, triglycidyl isocyanate, etc.,
These monomers may be used alone or in combination of two or more.

(6) (Photopolymerization Inhibitor) In order to increase the shape of the liquid crystal droplets, it is preferable to add a compound that inhibits the polymerization reaction, in addition to the above polymerizable material. If the polymer wall is formed immediately after irradiation with light, the polymer wall is not formed according to the pattern because the polymer wall is formed before the movement of the monomer or the liquid crystal material is completed. Specifically, there are monomers and compounds that stabilize radicals in a resonance system after radical generation,
Specifically, it is styrene, p-chlorostyrene, p-fluorostyrene, p-methylstyrene, p-phenylstyrene, nitrobenzene or the like.

(7) (Polymerization Initiator) As the photopolymerization initiator, Irgacure 651, 18
4,907, Darocure 1173, 1116, 2
Common photoinitiators such as 959 can be used. Further, in order to improve the retention rate, a sensitizer or the like which can be polymerized with visible light may be used. The retention ratio is 16.5 m with the electric charge Co accumulated in the liquid crystal cell.
It is defined by the ratio with the charge amount C held for s. That is, the retention rate = C / Co × 100 (%).

As the thermal polymerization initiator, a peroxide such as biphenyl-oxide, t-butylperoxide or the like and a radical generator such as AIBN can be used.

Further, the addition amount of these polymerization initiators varies depending on the reactivity of each compound and is not particularly limited in the present invention, but is added to the mixture of the liquid crystal material and the polymerizable material (including the liquid crystal polymerizable material). It is preferably 5 to 0.01%. When it is 5% or more, the phase separation speed of the liquid crystal material and the polymer material is too fast, which makes control difficult, the liquid crystal droplet becomes small, the driving voltage becomes high, and the alignment control force of the alignment film on the substrate becomes weak. In addition, the liquid crystal region becomes small in the picture element (when a photomask is used, liquid crystal droplets are formed in the light shielding part), and the contrast is lowered. 0.
If it is less than 01%, the polymerizable material cannot be sufficiently cured.

(8) (Liquid Crystal Material) As for the liquid crystal material, a nematic liquid crystal (liquid crystal for dual frequency drive,
Included are liquid crystals having a dielectric anisotropy Δε <0), cholesteric liquid crystals (particularly liquid crystals having selective reflection characteristics for visible light), smectic liquid crystals, ferroelectric liquid crystals, and discotic liquid crystals. These liquid crystal materials may be mixed, and in particular, nematic liquid crystal or nematic liquid crystal to which a cholesteric liquid crystal (chiral agent) is added is preferable in view of characteristics. More preferably, a liquid crystal material having excellent chemical reaction resistance is preferable because it is accompanied by a photopolymerization reaction during processing.

Specifically, it is a liquid crystal material having a functional group such as a fluorine atom in the compound. Specifically, ZLI-
4801-000, ZLI-4792 (manufactured by Merck & Co., Inc.) and the like.

(9) (Liquid-Crystalline Polymerization Material) In order to inject and solidify in a nematic state in which a mixture of a liquid crystal material and a polymerizable material has a liquid crystal state, a liquid crystal polymerization material having both properties is used. Is preferred. These compounds have the effects of lowering the volatility of the polymerizable material during vacuum injection and suppressing the composition change during injection of the mixture (liquid crystal-polymerizable material-polymerization initiator). In selecting a liquid crystal material having a polymerizable functional group in the molecule from these liquid crystal materials, it is preferable from the viewpoint of compatibility that the portions exhibiting liquid crystal characteristics are similar. In particular, regarding the F and Cl liquid crystal materials having a unique chemical environment, it is preferable that the liquid crystal material having a polymerizable functional group is also the F and Cl liquid crystal material.

Although not particularly limited in the present invention, the compound having a liquid crystalline functional group in the molecule used in the present invention is a compound represented by the following chemical formula 1 or the like, which disturbs the liquid crystallinity of the host liquid crystal molecule. It is a compound that is difficult to do.

[0166]

Embedded image A-B-LC A in Chemical Formula 1 represents a polymerizable functional group, and CH ₂ ═C
_{H-, CH 2 = CH-COO-} , CH 2 = CH-COO
-,

[0167]

[Chemical 2]

A functional group having an unsaturated bond such as or a heterocyclic structure having a strain is shown. Moreover, B is a linking group connecting the polymerizable functional group and a liquid crystal compound, specifically an alkyl chain _{(- (CH 2) n -} ), an ester bond (-COO
-), an ether bond (-O-), a polyethylene glycol chain (-CH ₂ CH ₂ O-), and a linking group formed by combining these linking groups, to exhibit liquid crystallinity when mixed with the liquid crystal material Since it is preferred, a linking group having a length having 6 or more bonds from the polymerizable functional group to the rigid part of the liquid crystal molecule is particularly preferred. LC represents a liquid crystal compound, and is a compound represented by the following chemical formula 3, a cholesterol ring or a derivative thereof, or the like.

[0169]

Embedded image In the above chemical formula, G is a polar group that causes dielectric anisotropy of liquid crystal and the like, and is —CN, —OCH ₃ , —F, —C.
_{l, -OCF 3, -OCCl 3,} -H, -R: benzene ring having a functional group (R alkyl group), a cyclohexane ring, para-diphenyl ring, a phenyl cyclohexane ring. E is a functional group that connects D and G, and is a single bond, -C
_{H 2 -, - CH 2 CH} =, - CH 2 CH 2 -, - O -, - C
≡C-, -CH = CH- and the like. D is a functional group that binds to B in the chemical formula 1 and is a part that influences the magnitude of dielectric anisotropy and refractive index anisotropy of liquid crystal molecules. , 1,10-diphenyl ring,
Examples include 1,4-cyclohexane ring and 1,10-phenylcyclohexane ring.

(10) (Mixing ratio of liquid crystal material and polymerizable material) The weight ratio of mixing the liquid crystal material and the polymerizable material varies depending on the pixel size, but the liquid crystal material: polymerizable material is 50: 50-9.
It is preferably 7: 3, more preferably 70:30 to 9
It is 5: 5. When the content of the liquid crystal material is less than 50%, the interaction of the polymer wall with the liquid crystal material is increased, the driving voltage of the cell is significantly increased, and the practicality is lost. Further, if the liquid crystal material content exceeds 97%, the physical strength of the polymer wall is lowered and stable performance cannot be obtained. Further, the polymerization ratio of the mixture of the compound having liquid crystallinity and the non-liquid crystalline polymerizable material may be 0.5% or more of the compound having liquid crystallinity, and particularly when the ferroelectric liquid crystal is used, it has liquid crystallinity. By making the compound 100%, two regions of low molecular weight liquid crystal and high molecular weight liquid crystal are formed,
A ferroelectric liquid crystal display device capable of gradation display can be prepared by setting the voltage to a voltage driven by each compound.

(11) (Driving Method) The prepared cell can be driven by a driving method such as simple matrix driving, active driving using TFT (thin film transistor) or MIM (metal-insulating film-metal structure switching element), or the like. It was These driving methods are not particularly limited in the present invention.

(12) (Substrate Material) In the case of polymerizing using light, one of the substrates to be used may be a material that partially transmits light, and glass, quartz, a transparent plastic material or the like can be used. When used as a reflective liquid crystal display element, a non-transmissive substrate such as a Si substrate can be used as the substrate on the reflection side.

Specific examples and comparative examples will be given below.
It will be described in more detail.

(Embodiment 1) Hereinafter, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to this.

FIG. 1 is a sectional view showing a liquid crystal display element that is Embodiment 1 of the present invention. In FIG. 1, this liquid crystal display element is a display medium in which a pair of substrates 1 and 2 made of glass plates or the like are arranged to face each other, and a liquid crystal region 7 surrounded by a polymer wall 8 is sandwiched therebetween. . Electrode wiring as an electrode 3 is formed on the display medium side surface of one substrate 1, and electrode wiring as an electrode 4 is formed on the display medium side surface of the other substrate 2 so that the electrodes 3 and 4 face each other. The part is the picture element. A thin film 5 is formed on a portion of the surface of the substrate 1 on the display medium side other than the picture element portion, and a thin film 6 is formed on a portion of the surface of the other substrate 2 on the display medium side surface other than the picture element portion. The surface free energy of the portion other than the elementary portion is lower than the surface free energy of the picture element portion.

The liquid crystal display device having such a structure is
For example, it can be manufactured as follows.

First, the thin films 5 and 6 are formed on the substrate 1 having the electrode 3 formed thereon and the substrate 2 having the electrode 4 formed thereon. The thin films 5 and 6 can be formed by a method of forming by a PI printing method or a method of applying a thin film material by spin coating and then obtaining a required pattern by using a mask.

Next, as shown in FIG. 2, the substrates on which the electrodes 3 and 4 and the thin films 5 and 6 are formed are made to face each other so that the electrodes 3 and 4 face each other, and they are attached via a spacer of 6 μm. A liquid crystal cell is also created.

A mixed material containing at least a liquid crystal material, a photopolymerizable material, and a photopolymerization initiator and uniformly mixed with each other is injected into the gap of the liquid crystal cell.

Next, the mixed material is irradiated with ultraviolet rays from the outside of the liquid crystal cell. By this ultraviolet irradiation, the photopolymerizable material gathered on the thin films 5 and 6 other than the picture element portion is cured to form a polymer material, and the liquid crystal material is extruded onto the electrodes 3 and 4, and the liquid crystal material and the polymer The material undergoes phase separation. as a result,
A display medium in which the liquid crystal region 7 is surrounded by the polymer wall 8 is formed between the substrates 1 and 2. When irradiating the ultraviolet light, the substrate on the ultraviolet light source side of the display medium, inside or outside, to form a photomask having a light-shielding portion in the portion corresponding to the picture element, and irradiate the ultraviolet light through the photomask,
The phase separation between the liquid crystal material and the polymer material can be more favorably performed.

As the liquid crystal material, any organic mixture which exhibits a liquid crystal state at around room temperature can be used as described above.

Further, in order to clarify the phase separation between the liquid crystal material and the polymer material and to speed up the response speed of the liquid crystal display device, a liquid crystalline polymer material is added to the mixed material. This liquid crystalline polymer material is a compound having in its molecule both a photopolymerizable functional group such as an acrylate group and a methacrylate group and a functional group exhibiting rigid liquid crystallinity. In selecting the above-mentioned liquid crystalline polymer material, it is preferable that the portion exhibiting liquid crystallinity is similar to the above liquid crystal material from the viewpoint of compatibility. In particular, when F-based or Cl-based liquid crystal having a unique chemical environment is used as the liquid crystal material, it is preferable to use F-based or Cl-based liquid crystal material as the liquid crystalline polymer material. Further, when a ferroelectric liquid crystal is used as the liquid crystal material, it is preferable to use a liquid crystalline polymer material having a ferroelectric liquid crystal in its molecule in order to create a stable smectic phase.

In the mixed material, the weight ratio of the liquid crystalline polymer material to the non-liquid crystalline photopolymerizable material may be 0.5% or more of the liquid crystalline polymer material. In particular, when a ferroelectric liquid crystal is used as the liquid crystal material, by setting the weight ratio of the liquid crystalline polymer material to 100%, two regions, a region made of a low molecular weight liquid crystal material and a region made of a high molecular weight liquid crystal material, are generated Can be made. In this case, a ferroelectric liquid crystal display element capable of gradation display can be prepared by setting the voltage to a voltage that drives each of the low molecular weight liquid crystal material and the high molecular weight liquid crystal material.

The weight ratio of mixing the liquid crystal material and the photopolymerizable material is 50:50 to 9 for the liquid crystal material: photopolymerizable material.
It is preferably 7: 3, more preferably 70: 3.
0 to 95: 5. When the weight ratio of the liquid crystal material is less than 50%, the driving voltage of the cell remarkably increases due to the polymer wall, and the practicality is lost. Further, when the weight ratio of the liquid crystal material exceeds 97%, the physical strength of the polymer wall decreases and stable performance cannot be obtained.

The above photopolymerization initiator is, for example, Irg.
acure 184, 651, 907 (manufactured by Ciba Geigy) and Darocure 1173, 1116, 2
959 (manufactured by E. Merck) and the like.

The photopolymerization initiator is preferably used in an amount of 0.1 to 5% by weight based on the total amount of the liquid crystal material and the photopolymerizable material. When the photopolymerization initiator is less than 0.1% by weight, the photopolymerization reaction does not sufficiently occur. On the other hand, if it exceeds 5% by weight, the phase separation speed between the liquid crystal material and the polymer material becomes too fast, the obtained liquid crystal region becomes small, and the cell driving voltage becomes high.

As a material of the thin film provided on the surface of the substrate on the display medium side, a general polymer material can be used. For example, OFPR-800 (manufactured by Tokyo Applied Chemistry), SE150 (manufactured by Nissan Kagaku), JALS-203,
Examples thereof include polyimide such as 204 (manufactured by Japan Synthetic Rubber), thermoplastic resins such as polystyrene, PMMA, polyphenyl oxide, and polycarbonate, and condensation type polymers such as novolac resin. Further, a surfactant may be added to bring the surface free energy value of these polymer materials close to the surface free energy value of the photopolymerizable material. As the above-mentioned surfactant, those which are generally commercially available can be used. However, when an anionic surfactant or a cationic surfactant is used, the retention rate may decrease, so that a nonionic surfactant is used. It is preferable to use. The thin film, the value of the surface free energy of the portion other than the picture element portion on the display medium side of the substrate is smaller than the value of the surface free energy of the picture element portion, the photopolymerizable to the portion other than the picture element portion. Used to facilitate the gathering of materials. Therefore, the polymer material is not limited to the above-mentioned polymer material, and any polymer material having a surface free energy value close to the surface free energy value of the polymerizable material can be used.

When the value of the surface free energy of the thin film is sufficiently close to the value of the surface free energy of the photopolymerizable material and phase separation occurs in the liquid crystal cell after injecting the mixed material, the state is kept as it is. The photopolymerizable material may be cured by irradiating the mixed material with ultraviolet rays. Further, it is possible to intentionally provide the ultraviolet irradiation pattern with a regular strength or weakness according to the required diameter of the liquid crystal region (for example, about the same as that of the picture element). In this case, the positions where the photopolymerization reaction occurs are regular, and liquid crystal regions having a uniform shape and size can be regularly disposed on a plane.

For example, in the portion where the ultraviolet irradiation intensity is high,
Since the photopolymerizable material has a high polymerization rate and the phase separation rate between the liquid crystal material and the polymer material is high, the polymer material is rapidly deposited and the liquid crystal material is extruded to a portion where the ultraviolet irradiation intensity is low. Therefore, a liquid crystal region is generated in a portion where the ultraviolet irradiation intensity is weak, and liquid crystal regions having a uniform shape and size can be regularly arranged on a plane. The phase separation between the liquid crystal material and the polymer material can be further clarified by matching the portion where the ultraviolet irradiation intensity is strong with the portion where the thin film is formed.

When providing an illuminance distribution in the ultraviolet irradiation pattern, it is desirable to use a photomask, a microlens, an interference plate, etc. to make a regular illuminance distribution. The position of the photomask may be inside or outside the liquid crystal cell (side surface of the display medium of the substrate or side surface opposite to the display medium),
What is necessary is that the ultraviolet rays to be irradiated can be regularly changed. When the photomask is separated from the cell, the image of the formed photomask is blurred and it is difficult to obtain a regular illuminance distribution. Therefore, it is desirable that the photomask be provided as close as possible to the mixed material containing the liquid crystal material and the photopolymerizable material.

Further, it is desirable that the light source of ultraviolet rays is also parallel rays as much as possible. However, in a ferroelectric liquid crystal display device, in order to improve impact resistance, a liquid crystal region smaller than that may be arranged around a liquid crystal region having a size similar to that of a picture element as a buffer. In that case, the edges of a light-shielding portion such as a photomask may be intentionally blurred, the photomask may be provided away from the cell body, or the parallelism of ultraviolet rays may be lowered to irradiate. The intensity of the ultraviolet irradiation by the photomask or the like may be set to 80% or less of the portion having the weak irradiation intensity and the portion having the strong irradiation intensity.

According to the study by the present inventor, when a photomask in which the size of the light-shielding portion for providing the illuminance distribution is 30% or less of the size of the picture element is used, the size of the picture element is 30%. A liquid crystal region having a size of not more than% can be obtained. When the size of the liquid crystal region is 30% or less of the size of the picture element as described above, the number of interfaces between the liquid crystal material and the polymer material increases in the picture element, and the display contrast is significantly reduced due to scattering at the interfaces. Become. In order to prevent this, it is preferable that the portion for weakening the irradiation intensity by blocking ultraviolet rays is made larger than the size of the picture element. Specifically, it is preferable to use a photomask provided with a light-shielding portion so that ultraviolet light is irradiated only to a portion other than the picture element. Furthermore, in a non-scattering mode liquid crystal display element that does not use the scattering generated between the polymer material and the liquid crystal material for display, when a portion with low irradiation intensity is provided by a photomask or the like, its shape is 30 pixels.
%, As long as it covers a portion of not less than 100% and locally reduces the ultraviolet intensity.

The liquid crystal display device thus obtained is
By providing a polarizing plate on the surface of the substrate opposite to the display medium side, conventional TN, STN, FLC (SSF), ECB
Liquid crystal materials used for liquid crystal display elements such as display modes
A liquid crystal display device having a structure in which a liquid crystal region is confined in a polymer wall can be used. Further, it is possible to obtain a large screen and a film, and it is possible to obtain a liquid crystal display device having excellent viewing angle characteristics and contrast.

Specific examples based on the first embodiment will be described below.

(Example 1a) I was placed on substrates 1 and 2 made of flint glass (made by Nippon Sheet Glass) having a thickness of 1.1 mm.
Two hundred electrodes 50 made of TO (mixture of indium oxide and tin oxide) and having a thickness of 50 nm and a width of 200 μm were formed at intervals of 50 μm. The value of the surface free energy of this ITO was 92.8 mN / m. This board 1,
2, thin films 5 and 6 were formed by applying OFPR-800 (manufactured by Tokyo Applied Chemistry) on the portions other than the portion (picture element portion) where the electrodes 3 and 4 shown in FIG. 2 overlap. At this time, the value of the surface free energy of the portion other than the picture element portion where the thin films 5 and 6 were formed was 36 mN / m. Place the substrates 1 and 2 in this state so that the electrodes 3 and 4 face each other.
Moreover, the liquid crystal cell was prepared by making the portions in which the thin films 5 and 6 are not formed face each other so as to face each other and pasting them through a spacer (not shown) having a diameter of 6 μm therebetween.

In this liquid crystal cell, a mixture of 0.1 g of trimethylolpropane trimethacrylate as a photopolymerizable material and 0.4 g of 2-ethylhexyl acrylate and 0.5 g of isobornyl acrylate, and Z as a liquid crystal material.
4 g of a mixture obtained by adding 0.3 w% of CN (cholesteric nonalate) to LI-3700-000 (manufactured by Merck).
And Irgacure 18 as a photopolymerization initiator
4 (manufactured by Ciba-Geigy) was uniformly mixed and injected.

Next, the liquid crystal cell was irradiated with ultraviolet rays at 10 mW / cm ² for 10 minutes using a high-pressure mercury lamp capable of producing parallel rays to cure the photopolymerizable material contained in the mixed material. As a result, as shown in FIG.
A liquid crystal region 7 surrounded by was formed.

Finally, polarizing plates were attached to the outside of the liquid crystal cell so that their polarization axes were orthogonal to each other.

Through the above steps, a liquid crystal display device having excellent viewing angle characteristics was obtained.

Example 1b A liquid crystal cell was prepared in the same manner as in Example 1a, and the same mixed material as in Example 1a was injected into this liquid crystal cell.

Next, a photomask having a light shielding portion 9 is arranged in a portion (picture element portion) where the electrodes 3 and 4 shown in FIG. 3 overlap each other, and a high pressure mercury lamp capable of obtaining parallel light rays is used.
Ultraviolet rays of 10 mW / from the photomask side to the liquid crystal cell
Irradiation was carried out at cm ² for 10 minutes.

Finally, as in Example 1a, polarizing plates were attached to the outside of the liquid crystal cell so that their polarizing axes were orthogonal to each other.

Through the above steps, a liquid crystal display device having an excellent viewing angle characteristic was obtained.

(Comparative Example 1) Similar to Example 1a, ITO (mixture of indium oxide and tin oxide) was formed on substrates 1 and 2 made of flint glass (made by Nippon Sheet Glass) having a thickness of 1.1 mm. 200 electrodes 3 and 4 having a thickness of 50 nm and a width of 200 μm were formed at intervals of 50 μm. The substrates 1 and 2 in this state were made to face each other so that the electrodes 3 and 4 face each other, and they were bonded together with a spacer of 6 μm interposed therebetween to form a liquid crystal cell.

The same mixed material as in Example 1a was injected into this liquid crystal cell.

Next, as in Example 1a, the liquid crystal cell was irradiated with ultraviolet rays at 10 mW / cm ² for 10 minutes using a high-pressure mercury lamp capable of producing parallel rays to cure the photopolymerizable material.

Finally, in the same manner as in Example 1a, polarizing plates were attached to the outside of the liquid crystal cell so that their polarizing axes were orthogonal to each other to obtain a liquid crystal display element.

Comparative Example 2 A liquid crystal cell was prepared in the same manner as in Comparative Example 1, and the same mixed material as in Example 1a was injected into this liquid crystal cell.

Next, as in Example 1b, a photomask having a light-shielding portion 9 is arranged at a portion (pixel portion) where the electrodes 3 and 4 shown in FIG. 3 overlap, and a high pressure mercury lamp capable of obtaining parallel light rays is obtained. The liquid crystal cell was irradiated with ultraviolet rays from the photomask side at 10 mW / cm ² for 10 minutes.

Finally, in the same manner as in Example 1a, polarizing plates were attached to the outside of the liquid crystal cell so that their polarizing axes were orthogonal to each other to obtain a liquid crystal display element.

Table 1 below shows the results of measuring the electro-optical characteristics of the liquid crystal display devices obtained in Examples 1a and 1b and Comparative Examples 1 and 2.

[0212]

[Table 1]

In Table 1, T _off represents the light transmittance when no voltage is applied, the driving voltage represents the voltage when the transmittance changes by 90%, and the response speed represents the value of τr + τd when 5 V is applied. . From this Table 1, it is understood that the liquid crystal display element of Example 1a has the same contrast and response speed as the liquid crystal display element of Comparative Example 2 produced by the method using the conventional photomask. Further, it is understood that the liquid crystal display element of Example 1b has more manufacturing steps than the liquid crystal display element of Example 1a, but can further improve the contrast and response speed.

Further, the liquid crystal display elements obtained in Examples 1a and 1b and Comparative Examples 1 and 2 were divided, the cell was peeled in liquid nitrogen, and the liquid crystal material was rinsed with acetone. After that, when the horizontal cross section of the formed polymer wall was observed with a SEM (scanning electron microscope), the images as shown in FIGS. 4A to 4D were obtained. The liquid crystal display element of Example 1a is
As shown in FIG. 4A, a liquid crystal display device of Comparative Example 2 (FIG.
A regular pattern similar to that of (d)) was obtained, and it was confirmed that the polymer material was less likely to enter the pixel. In addition, in the liquid crystal display element of Example 1b, as shown in FIG.
It was confirmed that a regular pattern was obtained, as shown in Fig. 3, and that the polymer material was less likely to enter the pixel.
The liquid crystal display element of Comparative Example 1 is irregular and is in the state of a polymer dispersion type liquid crystal display element.

(Example 1c) In this example, a liquid crystal display element in which display is performed by driving a TFT was prepared. First, as shown in FIGS. 5 and 6, JALS-204 is formed on a portion of the TFT substrate 40 on which the TFT 45 and the pixel electrode 42 are formed, other than the pixel electrode 42, and on the black mask 43 of the counter substrate 41. A thin film material obtained by adding a small amount of polyethylene glycol lauric acid monoester as a nonionic surfactant to (manufactured by Japan Synthetic Rubber) was subjected to PI printing to form thin films 46 and 47. At this time, the thin films 46, 4
The value of the surface free energy of the portion where 7 was formed (the portion outside the pixel portion) was 33 mN / m. Thin film 46,4
The surface free energy of the portion where 7 is not applied is 79.
It was 5 mN / m. The substrates 40 and 41 in this state were bonded to each other with a spacer (not shown) of 5 μm interposed therebetween to form a liquid crystal cell. A counter electrode 48 for the pixel electrode 42 is formed on the entire surface of the black mask 43.

A mixture of 0.1 g of trimethylolpropane trimethacrylate and 0.35 g of 2-ethylhexyl acrylate and 0.45 g of isobornyl acrylate was added to this liquid crystal cell as a photopolymerizable material, and ZLI-4792 (Merck Co., Ltd.) was used as a liquid crystal material. 4 g of a mixture prepared by adding 0.3 wt% of CN (cholesteric nonalate) to
And Irgacure 18 as a photopolymerization initiator
4 (manufactured by Ciba-Geigy) was uniformly mixed with 0.15 g, and a mixed material was vacuum-injected.

Next, as shown in FIG. 6, a photomask 49 having a light shielding portion 50 was placed so that the light shielding portion 50 corresponded to the pixel electrode 42. In this state, the liquid crystal cell was exposed to ultraviolet rays from the photomask side at 10 mW / cm ² for 10 minutes.
Irradiated for a minute to cure the photopolymerizable material. This allows
A liquid crystal region 51 surrounded by the polymer wall 52 was obtained.

(Comparative Example 3) A liquid crystal cell was prepared by bonding a TFT substrate 40 and a counter substrate 41 as shown in FIG. 5 with a spacer of 5 μm interposed therebetween.

The same mixed material as in Example 1c was vacuum-injected into this liquid crystal cell.

Next, as in Example 1c, the photomask 49 having the light shielding portion 50 was formed on the pixel electrode 42, and the light shielding portion 50 was formed.
The liquid crystal cell was irradiated with ultraviolet rays at 10 mW / cm ² for 10 minutes from the photomask side.

When the picture elements of the liquid crystal display elements obtained in the above Example 1c and Comparative Example 3 were observed with an optical microscope, the picture element of Example 1c showed a higher liquid crystal material than the picture element of Comparative Example 3. The phase separation between the polymer material and the polymer material was clear, and the polymer material was less likely to enter the picture element.

Further, when the electro-optical characteristics were measured, the liquid crystal display element of Example 1c had better contrast and response speed than the liquid crystal display element of Comparative Example 3.

Although the non-scattering mode liquid crystal display element has been described in the above-mentioned Examples 1, 1a to 1c, the present invention is not limited to this, and can be applied to a scattering-transmission mode liquid crystal display element.

In each of the above-described embodiments, the liquid crystal display element in which the display is performed by the simple matrix drive and the TFT (thin film transistor) drive has been described, but the MIM (Me
The present invention can also be applied to a liquid crystal display element in which display is performed by active driving using a Tal Insulator Metal) or the like, and the driving method is not limited.

A plastic film substrate or the like may be used as the pair of substrates arranged to face each other.

Example 2 Hereinafter, Example 2 of the present invention will be shown, but the present invention is not limited to this. This embodiment is similar to the above-described first embodiment, 1a to 1c, and corresponding parts are designated by the same reference numerals.

FIG. 16A shows a sectional view of the substrate of this embodiment, and FIG. 16B shows a sectional view taken along the section line AA of FIG. 16A. OM on a substrate 1 having ITO (a mixture of indium oxide and tin oxide, film thickness 50 nm) as a transparent electrode 20 on a glass substrate (1.1 mm thickness) 1.
Substrate 1 having resist 21 having a pattern shown in FIG. 16, which is obtained by applying 2 wt% of perfluorooctyl acrylate by spin coating to R83 (manufactured by Tokyo Ohka Co., Ltd.) and drying it, covering it with a photomask and irradiating it with ultraviolet rays. It was created. The surface free energy of the surface of ITO 20 of the substrate 1 and the surface free energy of the resist material thus prepared are shown in Table 2 below.
It was as shown in.

[0228]

[Table 2]

The surface free energies of the liquid crystal material and the photopolymerizable material were as shown in Table 3 below.

[0230]

[Table 3]

A liquid crystal cell was constructed by bonding the above substrate and the substrate having the surface on which the ITO 20 was formed to each other while keeping the cell thickness with a spacer having a diameter of 5.5 μm. In the prepared liquid crystal cell, 0.1 g of the compound 1 shown in the chemical formula 4 below, 0.2 g of p-fluorostyrene, 0.2 g of β- (perfluorooctyl) ethyl acrylate and further liquid crystal material ZLI-4792 (manufactured by Merck & Co., Inc .: S -811
(Chiral agent; manufactured by Merck & Co.) containing 0.4% by weight) 4.5
g and 0.025 of photoinitiator Irgacure651
g was mixed to prepare a mixture having the composition shown in Table 4 below.

[0232]

[Chemical 4]

[0233]

[Table 4]

The mixture was poured into the prepared cell, and then at 100 ° C. from the pattern side under a high pressure mercury lamp at 7 mW.
/ Cm ² was irradiated with ultraviolet rays for 8 minutes to cure the polymerizable material. Similar results were obtained when ultraviolet rays were irradiated from the opposite side. In this process, since the substrate temperature exceeds the isotropic temperature (uniformization temperature T _iso ) of the liquid crystal material, the liquid crystal molecules are not deposited, and the liquid crystal molecules are deposited in the subsequent slow cooling process. Furthermore, after irradiation with ultraviolet rays, while applying a voltage of ± 2.5 V (square wave: 60 Hz) to the cell, it was slowly cooled from 100 ° C. to 30 ° C. over 12 hours.

When the prepared cell was observed with a polarization microscope, as shown in FIG. 17, a liquid crystal domain D having the same regularity as the dot pattern (the same regularity as the pixel) was observed, and the pixel region 18 Almost one liquid crystal domain D in
Accompanied by a schlieren pattern (extinction pattern) 17 observed when the liquid crystal molecules inside are oriented in an axially symmetric or concentric shape, and the dark ring described with reference to FIG. 15 near the polymer wall 8 of the liquid crystal domain D. The structure was observed. Furthermore, when the produced cell was observed with a polarization microscope while applying a voltage, no disclination line was observed with the application of a voltage.

Two polarizing plates, which are perpendicular to each other, were attached to the front and rear of the prepared cell to prepare a liquid crystal display element having a structure in which the liquid crystal region 7 was surrounded by the polymer wall 8. Further, the cell was peeled from the two substrates in liquid nitrogen, the liquid crystal material was washed out with acetone, and the polymer material on the substrate after drying was observed with a laser microscope. As a result, adhesion of the polymer material having a thickness of about 0.1 μm was also observed in the liquid crystal region 7. The electro-optical characteristics of the prepared cell are shown in Table 5 below and FIG.
8 shows.

[0237]

[Table 5]

In Table 5, in the item of the reversal phenomenon in the halftone, ◯ indicates a state in which the reversal phenomenon does not occur, and x indicates a state in which the reversal phenomenon can be easily observed. In addition, the transmittance changes as the voltage is applied. The voltage when the transmittance changes by 90% with respect to the total amount of change is defined as V ₉₀ .

From Table 5 and FIG. 18 above, the cell of the present invention does not show the inversion phenomenon as seen in the TN cell of Comparative Example 5 (electro-optical characteristics are shown in FIG. 19) described later, and shows No increase in transmittance is observed in the wide viewing angle direction. In this measurement, two polarizing plates having polarization axes parallel to each other were used as blanks (transmittance 100%).

(Comparative Example 4) Of the substrate materials used in Example 2, the substrate 1 having the surface free energy patterned is shown in a plan view and a sectional view of FIG. Made of the same material. The substrate 1 was made into cells in the same manner as in Example 2, and a liquid crystal display element was produced under the same processing conditions. When the prepared cell was observed with a polarization microscope, as shown in FIG. 21, the polymerizable material gathered in the vicinity of the center of the rectangular portion having a low surface free energy and polymerized to form a polymer region 8. Was surrounded by a liquid crystal region 7. That is, from Example 2 and Comparative Example 4, when the surface free energy was patterned in this way, the photopolymerizable material having low surface free energy gathered in the mixed material in the region having low surface free energy, and The liquid crystal material having a high surface free energy gathers in a region having a high surface free energy and is energetically stabilized.

(Comparative Example 5) On the same substrate 1 as in Example 2,
An alignment film AL-4552 (manufactured by Japan Synthetic Rubber Co., Ltd.) was applied by a spin coating method, baked, and then rubbed with a nylon cloth, and cells were attached in the same manner as in Example 2 so that the alignment directions were orthogonal to each other. I matched it. A liquid crystal material ZLI-4792 (S-811) similar to that of Example 2 was added to the created cell.
0.4 wt% content) was injected, and two polarizing plates whose polarization axes were orthogonal to each other were attached to the front and the back of the cell to prepare a conventional TN display element.

The electro-optical characteristics of the prepared cell are shown in Table 5 and FIG.

(Embodiment 3) The color filter portions 22 in the shape of the picture element electrodes 20 as shown in FIG. 22 are arranged in a matrix, and the transparent portion 2 is provided around each color filter portion 22.
As shown in the plan view and the cross-sectional view of FIG. 23, the counter electrode substrate having the color filter 24 having the number 3 is formed, and the through holes 25 having the shape of the pixel electrode 20 are formed at the positions corresponding to the respective pixel electrodes 20. Then, a cell was formed with a TFT substrate 27 having a black matrix 26 containing β- (perfluorooctyl) ethyl acrylate on the surface so as to have a cell thickness of 5.5 μm. The same mixture as in Example 2 was injected into the prepared cell, and UV irradiation was performed from the color filter 24 side in the cell.

Observation of the prepared cell with a polarization microscope revealed that most of the picture elements had a monodomain liquid crystal region and the liquid crystal molecules in the domain were arranged in a spiral shape. Polarization axes are perpendicular to each other in the created cell 2
A polarizing plate was attached to the front and the rear of the cell to prepare a liquid crystal display device of this example. The light transmittance of the prepared cell when the voltage is OFF is shown in Table 5 above. In this measurement, a cell in which two polarizing plates having polarization axes parallel to each other (cell in which a liquid crystal material is not injected) was attached was used as a blank (transmittance 100%).

(Examples 4 and 5) In the following description, FIG.
See also. R-684 0.1 g, p-fluorostyrene 0.2 g, β- (perfluorooctyl) ethyl acrylate 0.2 g, and liquid crystal material ZLI-479.
2 (Merck & Co .: S-811 0.4 wt% content) 4.
5g and photoinitiator Irgacure651 0.02
A mixture with 5 g was made. The mixture prepared was used in Example 2.
The liquid crystal display element of the present Example 4 was produced by injecting it into the cell produced in the above step and processing it in the same manner as in the example 2. Further, the above mixture was poured into the cell prepared in Example 3 and processed in the same manner as in Example 3 to prepare a liquid crystal display device of this Example 5. Using the cell of Example 4 prepared, a voltage was turned on and OF by a polarization microscope.
Observation at F time was performed.

When the voltage is OFF, as shown in FIG. 24 (a), when the liquid crystal molecules in almost one liquid crystal domain D in the pixel region 18 are oriented in axial symmetry or concentric circles with respect to the central axis AX. A visible extinguishing pattern 17 was observed.

In this case, as shown in FIG. 24B, the disclination line 15 was generated near the polymer wall 8 around the liquid crystal region 7 when the voltage was applied. In the case of the fifth embodiment, the disclination line 1 is provided in the pixel area 18.
No. 5 was hardly observed, and it was confirmed that it was hidden in the black matrix 26 shown in FIG. 23 or that no disclination line was formed at all.

(Examples 6 and 7) A photopolymerizable material mixture was prepared with the composition shown in Table 4 above, mixed with the same liquid crystal material as in Example 2, and the same cells as in Example 2 were used. Two
The liquid crystal display devices of Examples 6 and 7 were prepared under the same processing conditions as described in (1) above. The effect of using a monomer having an F atom was measured using the prepared cell.

As a result, as shown in Table 5 above, in the cells to which the monomer having an F atom was added (Examples 2, 3, 6 and 10), the driving voltage was lowered and the saturation voltage was not applied. It had good characteristics with low transmittance.

(Comparative Example 6) A cell was prepared in the same manner as in Example 3, and the same mixture as in Example 3 was used. After injection of the mixture into the cell, ultraviolet irradiation was performed from the TFT substrate 27 side to prepare a cell. Two polarizing plates that are orthogonal to each other are attached to the front and back of the cell. In this comparative example, a granular polymer liquid crystal region was formed, and a polymer-dispersed liquid crystal display device having a rough display was formed.

(Example 8) (In the case of a thermopolymerizable material) Using the same cell as in Example 2, in the cell, 0.1 g of bisphenol A diglycidyl ether, 0.3 g of isobornyl acrylate, β- (Perfluorooctyl) ethyl acrylate 0.1 g, liquid crystal material ZLI-4792
(Merck KK: S-811 0.4 wt% content) 4.5
g and a thermal polymerization initiator t-butyl peroxide 0.05 g
The mixture was mixed and heated at 150 ° C. for 2 hours while applying a voltage (± 2.5 V (square wave: 60 Hz)), and then slowly cooled from 150 ° C. to 30 ° C. over 12 hours. When observing the created cell with a polarizing microscope,
The orientation was the same as in Example 2, and the viewing angle characteristics when sandwiched between two polarizing plates whose polarization directions are orthogonal to each other were also good.

(Example 9) (Method of thermally phase-separating first and then irradiating with ultraviolet rays) The same cell as in Example 2 was used, and the same material as in Example 2 was injected into the cell to obtain 100 The liquid crystal material is brought into an isotropic phase by heating to 100 ° C., and then the temperature is gradually lowered from 100 ° C. to phase-separate the polymerizable material and the liquid crystal material at 50 ° C.
The polymerizable material was cured by irradiating it with ultraviolet light for 10 minutes at 7 mW / cm ² under a high pressure mercury lamp. In this case, since the photopolymerizable material is cured after the phase separation of the liquid crystal material and the polymer material is performed in advance, almost no adhesion of the polymer material on the substrate in the liquid crystal region is observed, and the black Level improved. Furthermore, the retention rate, which indicates the ratio of the liquid crystal material in the liquid crystal region, was a high value of 97% (25 ° C.) because the polymerization reaction was less likely to occur in the liquid crystal region.

Furthermore, when the produced cell was observed with a polarization microscope, it was in the same orientation as in Example 2,
Moreover, it was confirmed that the irregularity of the display was small because the polymer walls were regularly formed.

Further, the viewing angle characteristics when the produced cell was sandwiched between two polarizing plates whose polarization directions were orthogonal to each other were good.

(Example 10) (When Compounds 1 and 2 are Mixed and Used) In a cell prepared in the same manner as in Example 2, 0.25 g of the compound 1 shown in the chemical formula 4 and the compound shown in the chemical formula 5 below. 2 of 0.17
5 g, 0.2 g of p-fluorostyrene, 0.15 g of β- (perfluorooctyl) ethyl acrylate, and liquid crystal material ZLI-4792 (Merck S-811).
0.4 g by weight) 4.5 g and photoinitiator Irgac
A mixture was prepared by mixing 0.025 g of ure651.

[0256]

[Chemical 5]

The mixture was poured into the prepared cell, and then, as in Example 9, the mixture in the cell was brought into an isotropic phase,
Then, the temperature was gradually lowered to deposit a liquid crystal layer, and then the liquid crystal layer was cured with ultraviolet rays.

Observation of the prepared cell with a polarizing microscope. The structure was as shown in FIG. However, Example 2
The ring-shaped structure on the outer periphery observed in the cell prepared in 1. was not observed. The ring-shaped structure on the outer periphery indicates that the liquid crystal molecules are arranged axially symmetrically with respect to the central axis of the pixel region. Further, as a result of observing while applying a voltage, no disclination line was observed. In addition, the polarization directions of the created cells are orthogonal to each other.
The viewing angle characteristics when sandwiched between the polarizing plates were also good.

(Examples 11, 12, 13 and Comparative Example 7)
(Resist Material on Substrate) In the following description, FIG. 16 will be referred to. Glass substrate (1.1
(mm thickness) 1 on a substrate having ITO (a mixture of indium oxide and tin oxide, film thickness 50 nm) as a transparent electrode 20 and 0 w in OMR83 (manufactured by Tokyo Ohka Co., Ltd.).
t% (Example 11), 4 wt% (Example 12) β-
After (perfluorooctyl) ethyl acrylate was applied by spin coating and dried, it was covered with a photomask and irradiated with ultraviolet rays to produce a substrate having a resist 21 having the same pattern as in Example 2. A substrate having a similar resist pattern was prepared using OFPR800 (manufactured by Tokyo Ohka Co., Ltd.) (Example 13). Furthermore, OFPR800
Epoxy ester 3002 in (manufactured by Tokyo Ohka Co., Ltd.)
A substrate having a similar resist pattern was prepared using a resist material containing 2 wt% of M (Kyoeisha Oil and Fat Chemical Co., Ltd.) (Comparative Example 7). The surface free energies of the thin films formed by the resist material were as shown in Table 6 below. The value of the surface free energy of ITO used here was 92.8 mN / m. With the above substrate material,
A cell was prepared in the same manner as in Example 2, and a liquid crystal-polymer composite element was prepared using the same material.

[0260]

[Table 6]

When the cells prepared in Examples 2, 11 to 13 were observed with a polarization microscope, it was confirmed that all the cells were resist 21.
The structure was such that the polymer material formed a wall on top, but as the difference in surface free energy increased, the regularity of the polymer wall improved and the graininess decreased. Especially, the surface free energy difference between the resist and ITO is 14.6 m.
In Comparative Example 7 where N / m, the regularity of the polymer wall is hardly seen, and the controllability of individually forming the liquid crystal region within the range of the picture element is poor.

Furthermore, the viewing angle characteristics when the produced cell was sandwiched between two polarizing plates whose polarization directions were orthogonal to each other were good.

(Embodiment 14) (When patterned on both substrates) In the following description, FIG. 16 is also referred to. Two substrates having regions with different surface free energies prepared in Example 2 were used, and the substrates were bonded to each other so that the patterns of the resist 21 were vertically overlapped with each other to prepare a cell. The same material as in Example 9 was used for the prepared cell, and the liquid crystal material and the polymer material were similarly phase-separated. Observation of the prepared cell with a polarizing microscope revealed that a polymer wall having an almost perfect pattern was formed.

Further, the viewing angle characteristics when the produced cell was sandwiched between two polarizing plates whose polarization directions were orthogonal to each other were good.

(Examples 15, 16, 17 and Comparative Example 8)
(Cell Gap) Four substrates having regions having the same pattern of surface free energy difference as the material of Comparative Example 7 and having different thicknesses of the regions as shown in Table 7 below were prepared ( Examples 15, 16, 17 and Comparative Example 8). A cell was prepared in the same manner as in Comparative Example 7 using each of the prepared substrates. Observation of each created cell with a polarizing microscope. In the cells of Examples 15 to 17, regular polymer walls were formed, but in Comparative Example 8, the mixed material did not sufficiently enter the cells and a large number of bubbles were included because the cell gap was thin.

[0266]

[Table 7]

(Example 18) (Polymer matrix S)
TN) In the following description, FIG. 16 is also referred to. On a glass substrate (1.1 mm thick) 1 having ITO (50 nm) as a transparent electrode 20, a polyimide alignment film (San Ever 150: Nissan Chemical Co., Ltd.) is applied, and O is applied thereon.
2 wt% of β- (perfluorooctyl) ethyl acrylate was applied to MR83 (manufactured by Tokyo Ohka Co., Ltd.) by spin coating, dried, and then covered with a photomask and irradiated with ultraviolet rays to form a resist 21 having the same pattern as in Example 2. Was prepared. The substrate thus prepared was rubbed in one direction to prepare an oriented substrate. As the counter substrate, the substrate 1 coated with only the polyimide film was rubbed in the same manner as the above substrate. The rubbing directions of both substrates are 2
A cell for STN was prepared by crossing at 40 ° and pasting using a spacer so that the cell thickness was 9 μm. R684 (manufactured by Nippon Kayaku Co., Ltd.) 0.2 g, p-
Phenyl styrene 0.1 g, stearyl acrylate 0.1 g, compound 2 shown in Chemical formula 5 above 0.6 g, and liquid crystal material ZLI-4427 (twist angle adjusted to 240 ° with S-811 (manufactured by Merck)) 4 g , Photopolymerization initiator Ir
A mixture prepared by mixing 0.025 g of gacure651 was injected, and the photopolymerizable material in the cell was cured in the same manner as in Example 9.

When the produced cell was observed with a polarization microscope, as shown in FIG. 25, STN-aligned liquid crystal regions 7 were respectively formed in regions substantially corresponding to the resists 21, and each liquid crystal region 7 was surrounded. The patterned polymer region 8 was formed. The characteristics of the prepared cell are shown in Table 8 below. The display characteristics of this element were equivalent to those of the normal STN mode cell shown in Comparative Example 9, and there was almost no display change when the cell was pressed with a pen.

[0269]

[Table 8]

(Comparative Example 9) Using the substrate of Example 18 without forming the resist 21 and having no region having a surface free energy difference, a cell having a normal STN orientation was prepared. The same liquid crystal material as in Example 18 was used. Table 8 above shows the contrast of this cell, the response speed, and the presence or absence of display change when the display section is pressed with a pen.
Shown in. In this comparative example, since the resist 21 is not formed, it can be seen that when the display portion is pressed by the pen, the substrate is deformed and the display state is changed.

(Example 19) (When Surface Free Energy of Liquid Crystal Material and Polymerizable Material are Reversed) On the substrate 1 having ITO 20 used in Example 2, O
Example 3 was spin-coated with MR83 (manufactured by Tokyo Ohka Co., Ltd.).
22 is used to expose-phenomenon using a mask having a pattern in which the color filter portion 22 and the transparent portion 23 of the color filter 24 shown in FIG. A substrate having a resist pattern was created. A cell was formed by bonding the above-mentioned substrate and the substrate having the surface of the ITO 20 while keeping the cell thickness with a spacer of 5.5 μm. 0.04 g of R684, 0.2 g of p-fluorostyrene, 4.4 g of a liquid crystal material ZLI-4792 (manufactured by Merck & Co., Inc .: 0.4% by weight of S-811) and 0.4 g of a photopolymerization initiator Irgacure651 were added to the prepared cell. A mixture of 025 g was injected and cured. The surface free energy of the polymerizable material is 39.2 mN / m, which is a value larger than the surface free energy (32 mN / m) of the liquid crystal material. The pattern of the polymer wall and the liquid crystal region created is
The pattern was the reverse of that of Example 3.

A display panel was prepared from the prepared cells in the same manner as in Example 2. When the produced display panel was observed with a polarization microscope, the polymer material was gathered on the ITO and the liquid crystal material was gathered on the resist.

Even when the surface free energy is opposite to that of the second embodiment as in this embodiment, the polymer wall and the liquid crystal region are intentionally arranged by appropriately arranging the regions having different surface free energies on the substrate. Can be placed at.

(Example 20) 1.1 m thoroughly washed
On a glass substrate (thickness # 7059, manufactured by Corning Co., Ltd.) having a thickness of m, 100 nm of ITO is vapor-deposited as a transparent electrode, and a pitch of 10 is obtained through a spin coating of photoresist, a UV exposure / development step, an ITO etching step / resist stripping step.
A stripe-shaped electrode having a width of 0 μm (width of electrode portion: 80 μm, electrode interval: 20 μm) was formed. The two substrates thus produced were attached to each other so that the surfaces of the substrates on which electrodes were formed faced each other and the directions of the electrodes of the respective substrates were orthogonal to each other, to produce a cell of a liquid crystal display element. . The distance between the two substrates was kept constant by spraying spacers of 5 μm.

Materials to be injected into this liquid crystal cell are shown in Table 9 below.
The composition was sufficiently mixed at the composition ratio shown in (1), and injection was performed by the vacuum injection method while keeping the state of not being exposed to ultraviolet rays.

[0276]

[Table 9]

[0277] The electrodes of the thus prepared prepared cells were processed so that a voltage could be applied from the outside. Then, the temperature of the cell was kept at 100 ° C. for 1 hour in a constant temperature bath, and then a 60 Hz rectangular wave (± 5 V) was applied to the electrodes on the substrates on both sides of the cell. While maintaining this applied voltage, the cell was gradually cooled to 74 ° C. This temperature is
It is a temperature at which it is confirmed that this mixture undergoes phase separation into a liquid crystal phase and an isotropic phase of a polymer material. Further, while maintaining the applied voltage and the temperature of the cell, ultraviolet rays having an illuminance of 7 mW / cm ² (365 nm) were irradiated by a high-pressure mercury lamp for 10 minutes to make a liquid crystal phase and an isotropic phase formed by the controlled phase separation. The spatial distribution of was fixed as the structure of the liquid crystal region and the polymer region. After that, the applied voltage was removed, and a polarizer and an analyzer were attached on both substrates of the cell so that their transmission axes were orthogonal to each other. In this way, a liquid crystal display element was produced. FIG. 26 shows the result of observation of the liquid crystal display device thus manufactured with a polarization microscope. In addition, the observation result of the liquid crystal display device of Example 20 and Comparative Example 1 described later.
Table 10 below shows the observation results of the liquid crystal display device of No. 0.

In FIG. 26, reference numerals A ₁ and A ₂ indicate the striped electrode portions, and reference numerals B ₁ and B ₂ indicate non-electrode portions between the electrodes. As shown here, the liquid crystal region 7
It can be seen that are well-controlled and arranged in the region to which the electric field is applied, and the polymer region 8 is well-controlled and arranged in the non-electrode portion. An extinction pattern 17 was observed in each liquid crystal region 7. The extinction pattern 17 was parallel to each transmission axis direction of the polarizer and the analyzer, and the extinction pattern 17 deteriorated the display panel quality. do not do.

With this element, a good display without inversion was obtained, instead of the viewing angle characteristics of the conventional TN mode element. Furthermore, the unevenness of the transmittance was not observed even by visual observation, and the roughness was not observed even when observed from a position 10 cm away from the cell.

[0280]

[Table 10]

(Comparative Example 10) A cell was prepared by the same method as in Example 20, and similarly, after processing the electrodes so that the voltage was applied to the display electrodes, the display electrodes were short-circuited and the voltage was changed. The state where no voltage is applied is maintained. Then, the same material as in Example 20 was injected by the vacuum injection method. This cell was heated to 100 ° C. in a constant temperature layer and stored for 1 hour. Further, the cell was gradually cooled to 74 ° C. Then, while keeping the temperature of this substrate for 10 minutes,
Illuminance 7 mW / cm ² (wavelength 365n
The spatial distribution of the liquid crystal phase and the isotropic phase formed by phase separation was fixed as the structure of the liquid crystal region and the polymer region by irradiating the ultraviolet ray of m). Then, a polarizing film was attached on both side substrates of the cell so that their transmission axes were orthogonal to each other, to produce a liquid crystal display element.

FIG. 27 shows the result of observation of the liquid crystal display element thus manufactured with a polarization microscope. Reference numerals A ₁ , A ₂ , B ₁ and B ₂ in FIG. 27 are the same as those in FIG. As shown in FIG. 27, in this comparative example, the position and shape of the liquid crystal region are not sufficiently controlled as in Example 20 shown in FIG. In addition, the size also varied.

With this element, a good display having no viewing angle characteristic as in the conventional TN mode element and no inversion was obtained. However, in visual observation, unevenness in the transmittance was observed as shown in Table 10 above, and roughness was also observed in the observation from a distance of 30 cm from the cell.

Example 21 A polyimide alignment film was applied by spin coating to the surface of an electrode on a substrate formed in the same manner as in Example 20, and a rubbing treatment was performed.
The two substrates were bonded together with a spacer interposed therebetween in the same manner as in Example 20. However, the spacer used was 6.5 μm. Table 11 below shows the cells that were not injected.
The mixture obtained by thoroughly mixing the above materials was injected by a vacuum injection method.

[0285]

[Table 11]

Here, the liquid crystal material is S based on ZLI4427.
-811 is mixed, the chiral pitch p and the cell gap d are mixed.
Was adjusted in advance so that and became d / p = 0.5. After that, the cell temperature was kept at 100 ° C. for 1 hour in the constant temperature layer, and then a 60 Hz rectangular wave (± 5 V) was applied to the display electrodes on the substrates on both sides of the cell. While maintaining this applied voltage, the cell was gradually cooled to 71 ° C. This temperature is a temperature which has been confirmed in advance that the mixture undergoes phase separation into a liquid crystal phase and an isotropic phase. An ordered structure of a liquid crystal phase and an isotropic phase formed by controlled phase separation by irradiating ultraviolet rays with an illuminance of 7 mW / cm ² (365 nm) from a high-pressure mercury lamp for 8 minutes while maintaining the applied voltage and cell temperature. Was fixed as the structure of the liquid crystal region and the polymer region. After that, the applied voltage was removed, and the polarizer film and the analyzer film were attached on both side substrates of the cell. In this way, a liquid crystal display element was produced.

The result of observing this liquid crystal display element with a polarization microscope is as shown in FIG. The optical characteristics of the liquid crystal region were similar to those of the normal STN mode. Reference numerals A ₁ , A ₂ , B ₁ and B ₂ in FIG. 29 are the same as the reference numerals in FIG. Also in this embodiment, it can be seen that the position and shape of the liquid crystal region 7 are well controlled and formed in the region to which the electric field is applied by the stripe electrode. In addition, in this example, the extinction pattern shown in FIG. 27 and the like was not observed.

In this liquid crystal display element, unlike the conventional liquid crystal display element, no change in display color was observed even when pressure was applied to the surface of the element. In addition, uneven display,
No graininess was observed.

(Embodiment 22) A TFT (Thin Film Transistor) used for active matrix driving.
tor) was formed and an alignment film was formed on each of the glass substrate and the counter substrate to prepare an unimplanted cell. Here, unlike the case of a liquid crystal display element using a normal TFT, the alignment film arranged closest to the liquid crystal layer of the substrate was not rubbed. The terminal electrode was processed so that a voltage was applied to the display transparent electrode portion of this substrate, and the mixture of Table 9 was injected by the vacuum injection method.
This cell is in a constant temperature layer, and the temperature of the cell is set to 100 ° C. 1
After holding for a period of time, the TFT on the electrodes on the substrate on both sides of the cell
A 60 Hz square wave (± 5 volts) was applied through. While maintaining this applied voltage, slowly cool the cell to 74 ° C.
With the applied voltage and the cell temperature maintained, the illuminance was 7 mW / cm ² (365 n
The spatial structure of the liquid crystal phase and the isotropic phase formed by controlled phase separation was fixed as the structure of the liquid crystal region and the polymer region by irradiating the ultraviolet light of m).

The irradiation time is longer than that in Example 20,
This is because the irradiation of ultraviolet rays is applied from the side of the substrate on which the TFTs are formed, so that the ultraviolet rays are attenuated by the drive wiring between the picture elements.

Thereafter, the applied voltage was removed, and a polarizer film and an analyzer film were attached on both side substrates of the cell so that their transmission axes were orthogonal to each other. In this way, a liquid crystal display element was produced. FIG. 28 shows the observation result of the liquid crystal display device thus manufactured by a polarization microscope. Figure 2
As shown in FIG. 8, the liquid crystal region 7 was formed by well controlling the position and shape of the picture element. Further, the polymer region 8 was scarcely formed in the picture element region related to display.

With this device, good display with no inversion and not with the viewing angle characteristics as in the conventional TN mode device was obtained. Furthermore, no unevenness in transmittance was observed even by visual observation, and no roughness was observed even when observed from a place 10 cm from the cell.

(Embodiment 23) FIG. 30 is a sectional view showing a liquid crystal display element of the embodiment 23. In FIG. 30, this liquid crystal display element is a display medium in which a pair of substrates 1 and 2 made of a glass plate or the like are arranged to face each other, and a liquid crystal region 7 surrounded by a polymer wall 8 is sandwiched therebetween. . Electrode wiring as an electrode 3 is formed on the display medium side surface of one substrate 1, and electrode wiring as an electrode 4 is formed on the display medium side surface of the other substrate 2 so that the electrodes 3 and 4 face each other. The part is the picture element.

The method of manufacturing the liquid crystal display element of this embodiment will be described below.

First, stripe-shaped ITO electrodes 3 and 4 are formed with a thickness of 200 nm on one surface of the pair of substrates 1 and 2. An alignment film is provided on this, for example, SE-
150 (manufactured by Nissan Kagaku) 50 nm by spin coating
It is applied with a film thickness of and baked. Further, the surface of the alignment film is rubbed in one direction with a nylon cloth. At this time, the contacting pressure of the rubbing cloth and the contact pressure are different between the electrode portion and the non-electrode portion. That is, as shown in FIG. 31, while rotating the rubbing roller 32 having the rubbing cloth 31 mounted on the surface thereof,
It can be seen that when the substrate 1 on which the electrode 3 and the alignment film 30 are formed is moved in the direction of the arrow, the electrode portion is more strongly in contact with the hair than the non-electrode portion. Therefore, the surface state of the alignment film 30 is different between the electrode portion and the non-electrode portion. The pair of substrates 1 and 2 are bonded together with the electrodes 3 and 4 facing each other through a spacer. A liquid crystal material, a mixture of a photo- or heat-polymerizable material and a polymerization initiator is injected and sandwiched between the substrates 1 and 2 formed in this way. Here, the liquid crystal material is ZLI-4792 (manufactured by Merck) 0 .612 g, isobornyl acrylate 0.03 g, β in photopolymerizable material
-(Perfluorooctyl) ethyl acrylate 0.0
3 g, p-fernylstyrene 0.008 g, and Irgacure 651 (manufactured by Ciba Geigy) as a photopolymerization initiator.
003g is used.

Next, the substrate is made of a liquid crystal material exhibiting the above isotropic phase 9
Heat to 5 ° C and keep warm. After that, the substrate is irradiated with ultraviolet light, but here, the irradiation is performed with an illuminance of 10 mW / cm ² for about 10 minutes. After that, the temperature is gradually cooled to room temperature, but the cooling speed is about −0.2 ° C./min. In this way, the polymer material is aggregated in the non-pixel portion by changing the heat retention to the gradual cooling in the isotropic phase. Next, the ultraviolet light is applied at 10 mW / cm ²
Irradiation is performed for 10 minutes to cure the polymer wall. When the state of formation of the polymer wall of the liquid crystal display element thus produced was observed with a microscope, the polymer wall 8 was formed in the non-pixel portion as shown in FIG. Further, the compatibilization temperature T _NI of the liquid crystal region 7 was 86 ° C. (T _NI = 90 ° C. in the case of only the liquid crystal material), so the liquid crystal material occupies almost the pixel portion, and the liquid crystal material − It can be seen that the phase separation of the polymer material is clearly performed.

(Embodiment 24) FIG. 33 is a cross sectional view showing a manufacturing process of a liquid crystal display element of the embodiment 24. Figure 3
3, in this liquid crystal display element, electrode wirings as electrodes 3 are formed on the display medium side surface of a pair of substrates 1 made of glass plates or the like, and an alignment film 30 is formed thereon. In the alignment film 30, a coating film 21 made of resist is formed in the recesses corresponding to the electrodes 3. The other substrate has the same structure as the substrate 1, and the portions of the electrodes of the respective substrates facing each other are picture elements.

The method of manufacturing the liquid crystal display element of this embodiment will be described below.

Striped ITO electrodes 3 are formed on a pair of transparent glass substrates 1, respectively. Approximately 50 SE-150 (manufactured by Nissan Chemical) as an alignment film 30 is formed on the electrode 3.
Then, the positive photoresist OFPR-80 is applied to the concave portion of the alignment film 30 which is the missing portion of the electrode 3.
0 (manufactured by Tokyo Ohka) 21 is about 50 nm by the photolithography process
It is formed with a film thickness of. The surface on which the alignment film 30 and the resist 21 are formed is rubbed with a nylon cloth or the like. At this time, the resist 21 may be stripped off by rubbing. The pair of substrates 1 thus obtained are bonded together via a spacer to form a cell.

A mixture of a liquid crystal material, a light- or heat-polymerizable material, and a polymerization initiator is sandwiched between the substrates 1 thus formed. Here, the liquid crystal material is ZLI-4792 (made by Merck).
0.612 g, isobornyl acrylate 0.03 g in photopolymerizable material, β- (perfluorooctyl) ethyl acrylate 0.03 g, p-phenylstyrene 0.0
08 g, and 0.003 g of Irgacure 651 (manufactured by Ciba Geigy) as a photopolymerization initiator. Next, the substrate 1 is heated to 95 ° C. at which the liquid crystal material exhibits an isotropic phase and kept as it is.

Thereafter, the substrate 1 is irradiated with ultraviolet light. Here, the irradiation is performed with an illuminance of 10 mW / cm ² for about 10 minutes. After that, slowly cool to room temperature, but the slow cooling speed is approx.
Perform at 0.2 ° C / min. In this way, the polymer material is aggregated in the non-pixel portions by performing the heat retention and the gradual cooling in the isotropic phase. Next, ultraviolet light is irradiated at room temperature for 10 minutes at an illuminance of 10 mW / cm ² to further cure the polymer wall. When the state of formation of the polymer wall of the liquid crystal display element thus produced was observed with a microscope, the polymer wall was formed in the non-pixel portion as shown in the image in FIG. Further, the compatibilization temperature T _NI of the liquid crystal region was measured to be 86 ° C. (T _NI = 9 in the case of the liquid crystal material only)
Since the temperature was 0 ° C.), the liquid crystal material almost occupied the pixel region, and it is clear that the phase separation between the liquid crystal material and the polymer material was clearly performed.

Example 25 As shown in Table 12 below,
Mixture samples a to e of photopolymerizable material were prepared. 1 g of the mixture of the photopolymerizable materials, 4 g of liquid crystal material E-7 (manufactured by Merck & Co .; containing 0.4% by weight of S-811), and further a photopolymerization initiator Irgacure 184 (manufactured by Ciba-Geigy) of 0. 025 g was evenly mixed and poured into a cell prepared in the same manner as in Example 2. 7 under high pressure mercury lamp
The photopolymerizable material was cured by irradiating it with ultraviolet rays for 8 minutes at mW / cm ² .

In samples a and b, a considerable amount of the polymer material also entered the pixel region, but in samples c, d and e, no polymer material was found in the pixel region.

[0304]

[Table 12]

Example 26 As shown in Table 12 above,
Mixture samples a to e of photopolymerizable material were prepared. 1 g of the mixture of the photopolymerizable materials, 4 g of the liquid crystal material E-7 (manufactured by Merck & Co .; containing 0.4% by weight of S-811), and 0.025% of a thermal polymerization initiator t-butyl peroxide.
g was uniformly mixed and injected into a cell prepared in the same manner as in Example 2. The liquid crystal cell was heated at 130 ° C. for 4 hours to cure the polymerizable material component.

Samples a and b as in Example 25
In the sample area, a considerable amount of the polymer material also entered, but in the samples c, d, and e, the polymer material was not found in the pixel area.

Example 27 A liquid crystal cell was prepared using the same material as in Example 25 above. These liquid crystal cells are once heated to 90 ° C, and the temperature is adjusted to 2
The liquid crystal cell was cooled to a low temperature at a rate of -0.5 ° C / min. While maintaining the liquid crystal cell at that temperature, ultraviolet rays were irradiated for 8 minutes at 7 mW / cm ² under a high pressure mercury lamp to cure the photopolymerizable material.

In samples a and b, the polymer material entered the pixel region, though a little. Sample c,
In d and e, no polymer material was found in the pixel region, and the amount of liquid crystal entering the polymer wall region was also reduced.

Each liquid crystal display element shown in each of the above embodiments has the following characteristics. Liquid crystal molecules in the liquid crystal region are oriented in axial symmetry.
In the device of the present invention, the viewing angle characteristics of the liquid crystal display device are improved because the alignment state of the liquid crystal molecules is axisymmetric. Specifically, it can be used for flat displays (personal computers, word processors, amusement devices, televisions) that make use of a wide viewing angle, display plates that utilize the shutter effect, windows, doors, walls, and the like.

Liquid crystal molecules in the liquid crystal region are unidirectionally aligned on at least one of the substrates. The device of the present invention is
Modes for aligning liquid crystal molecules on one substrate using the alignment control force of the alignment film, such as the TN and STN modes that have been used conventionally, are created in the polymer wall, and display characteristics due to changes in cell gap with external pressure It is a cell that prevents deterioration of the cell. It can be used as a pen-input type display element, a mobile information terminal element, etc., by making the most of its strong property against external pressure.

[0311]

As is apparent from the above description, according to the present invention, a polymer wall can be formed at a desired portion, and the phase separation between a liquid crystal material and a polymer material can be made clearer than before. Therefore, a liquid crystal display device having a high display contrast can be obtained. In addition, since the intrusion of the polymer material into the picture element can be reduced, the response speed can be improved.

By providing a polarizing plate, the conventional TN,
It can be applied to liquid crystal display elements such as STN, FLC (SSF), and ECB display modes, and a liquid crystal display element having good viewing angle characteristics and contrast can be obtained.

The application range of the liquid crystal display device of the present invention is extremely wide, and it can be used for, for example, a flat panel display device such as a projection television and a personal computer, a display plate utilizing a shutter effect, a window, a door, a wall and the like. In addition, a thin liquid crystal display element can be obtained by forming a cell using a thin substrate, a film substrate, or the like.

The present invention is a liquid crystal display device in which liquid crystal molecules are aligned in one pixel in an axially symmetrical manner with the center of the pixel as the center.
Since the liquid crystal molecules are oriented in all directions, it is possible to improve the deterioration of the contrast depending on the viewing angle direction, which is a problem in the conventional liquid crystal display device. In particular, in an element in which liquid crystal molecules are oriented in an axisymmetric manner in which the mixing of the polymer material into the pixel is suppressed, and the number of liquid crystal domains in the pixel is small, and the formation of disclination lines is suppressed,
At the same time that the viewing angle characteristics are improved, the light transmittance when the voltage is OFF is also improved.

Further, in the method for producing an element of the present invention, regions having different surface free energies are formed on the substrate surface, and the difference in surface free energy between the liquid crystal material and the photopolymerizable material is used to form the polymer wall. Patterning is performed, and both thermal polymerization and photopolymerization can be used, and complicated operations such as alignment of the photomask can be omitted.

The liquid crystal display device obtained by the present invention is one in which the liquid crystal material and the polymer material are phase-separated by selectively modifying the surface of the alignment film, and the aggregation position is controlled. That is how to control it. As described above, the steps of the electrodes, patterning with a thin film such as resist, selectively reforms the surface of the alignment film.These manufacturing methods are the mask method of fixing the conventional photomask to the outside of the substrate, Compared with the ITO self-alignment method in which the ITO electrode itself is formed so as not to be exposed to ultraviolet rays so as to serve as a photomask, it is not necessary to consider the constituent elements that can serve as a photomask, and the production of a conventionally used liquid crystal panel called rubbing. The process can be utilized, the process is extremely simple, and it is an extremely effective means in the manufacturing method.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a liquid crystal display element according to Examples 1 and 1a of the present invention.

2 is a plan view showing electrodes 3 and 4 in the liquid crystal display element of Example 1. FIG.

FIG. 3 is a plan view showing a manufacturing process of the liquid crystal display element of Example 1a.

FIG. 4 is a schematic diagram of an image obtained when observing the polymer wall formation state of the liquid crystal display elements of Examples 1a and 1b and Comparative Examples 1 and 2 with an SEM.

5 shows T of the liquid crystal display devices of Example 1c and Comparative example 3. FIG.
FIG. 4 is a plan view showing an FT substrate 10 and a counter substrate 11.

FIG. 6 is a cross-sectional view showing a manufacturing process of liquid crystal display elements of Example 1c and Comparative example 3.

FIG. 7 is a diagram illustrating the principle of visual characteristics of a conventional example.

FIG. 8 is a diagram illustrating the principle of improving the viewing angle characteristics of the present invention.

FIG. 9 is a cross-sectional view illustrating a region in which a polymer material is attached on a substrate in a liquid crystal region of a liquid crystal-polymer composite element.

FIG. 10 is a sectional view and a plan view of a cell of the present invention.

FIG. 11 is a diagram illustrating an example of the principle of separating a liquid crystal material and a polymerizable material in regions having different surface free energies.

FIG. 12 is a diagram illustrating another example of the principle of separating a liquid crystal material and a polymerizable material in regions having different surface free energies.

FIG. 13 is a schematic view of a mode of the present invention in which the orientation regulating force on the substrate is not used.

FIG. 14 is a plan view showing a picture element when a liquid crystal region in the picture element is divided and used.

FIG. 15 is a plan view of a polarization microscope observation example when a bifunctional liquid crystalline polymer material is used.

FIG. 16 is a diagram illustrating a pattern of a substrate created in an example.

FIG. 17 is a plan view of a polarization microscope observation example of a liquid crystal display element created in an example.

FIG. 18 is a graph showing viewing angle characteristics of the liquid crystal display element created in the example.

FIG. 19 is a graph showing viewing angle characteristics of a TN cell.

FIG. 20 is a diagram showing a pattern of a substrate created in a comparative example.

FIG. 21 is a plan view of a polarization microscope observation example of a liquid crystal display element created in a comparative example.

FIG. 22 is a plan view of a color filter used in the examples.

FIG. 23 is a plan view and a cross-sectional view of a TFT substrate used in an example.

FIG. 24 is a plan view of an example of observing picture elements of the example.

FIG. 25 is a plan view of a polarization microscope observation example of the liquid crystal display element created in the example.

FIG. 26 is a plan view of a liquid crystal display device obtained according to an example of the present invention, which is observed by a polarization microscope.

FIG. 27 is a plan view of a liquid crystal display element obtained by a comparative example of the present invention, observed by a polarization microscope.

FIG. 28 is a plan view of a liquid crystal display element obtained according to an example of the present invention, which is observed by a polarization microscope.

FIG. 29 is a plan view of a liquid crystal display device obtained according to an example of the present invention, which is observed by a polarization microscope.

FIG. 30 is a cross-sectional view of a liquid crystal display element of an example of the present invention.

FIG. 31 is a cross-sectional view showing the manufacturing process of the liquid crystal display element of the example of the present invention.

FIG. 32 is a plan view of a liquid crystal display element of this example.

FIG. 33 is a cross-sectional view showing the manufacturing process of the liquid crystal display element of the example of the present invention.

[Explanation of symbols]

 1, 2 substrate 3, 4 electrode 5, 6 thin film 7, 51 liquid crystal region 8, 52 polymer wall 9, 50 light-shielding portion 15 disclination line 17 extinction pattern 21 resist 30 alignment film 31 rubbing cloth 32 rubbing roller 40 TFT substrate 41 counter substrate 42 picture element electrode 43 black mask

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Wataru Horie 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture Sharp Corporation (72) Makoto Shiomi 22-22 Nagaike-cho, Abeno-ku, Osaka City, Osaka Prefecture Incorporated company (72) Masayuki Okamoto 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture Sharp Corporation (72) Inventor Koichi Fujimori 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture 72) Inventor Tokihiko Shinomiya 22-22 Nagaike-cho, Abeno-ku, Osaka City, Osaka Prefecture

Claims (34)

[Claims] 1. A pair of substrates including at least one substrate in which a plurality of regions having mutually different surface free energies are formed in a regular pattern; and a pair of substrates sandwiched between the pair of substrates to define a first surface free energy. The second surface free energy was defined by being sandwiched between a pair of substrates and a polymer wall formed of a polymer material obtained by curing a polymerizable material, which was formed on some of the plurality of regions that were formed. A plurality of liquid crystal regions formed on the other part of the plurality of regions and substantially surrounded by the polymer wall, the liquid crystal regions being formed of the liquid crystal material; Of the first surface free energy γ.
_p , the second surface free energy γ _E , the surface free energy γ _LC of the liquid crystal material, and the surface free energy γ _M of the polymer material are expressed by the relational expression (γ _E −γ _P ) × (γ _LC −γ _M )> 0 ... A liquid crystal display element selected as a combination satisfying (1). 2. The first surface energy is equal to the second surface energy.
The liquid crystal display element according to claim 1, which has a lower surface free energy than that of. And wherein the gap d ₁ of the pair of substrates in the pixel portion, and the gap d ₂ of a portion of the pair of substrates other than at least the picture elements portion, a relationship of d _1> d _2, The liquid crystal display element according to claim 1. 4. The gaps d ₁ and d ₂ are selected so as to satisfy the relationship 0.1 × d ₁ <d ₂ <0.9 × d ₁ (2). The liquid crystal display device according to item 1. 5. The liquid crystal display element is an active matrix display element, and a substrate having an active element among the pair of substrates has a light shielding region in a portion other than the pixel portion, 4. The liquid crystal display element according to claim 3, wherein the other substrate of the two has a region that partially transmits ultraviolet rays at least in a part other than the pixel portion. 6. A display medium having a pair of substrates arranged opposite to each other, a display medium provided between the pair of substrates, the display medium having a polymer wall and a plurality of liquid crystal regions surrounded by the polymer wall, It is formed on at least a part other than the picture element portion on the display medium side surface of at least one of the substrates, and the value of the surface free energy other than the picture element portion is smaller than the value of the surface free energy of the picture element portion. A liquid crystal display device comprising: 7. The liquid crystal according to claim 6, wherein 70% or more of the picture elements have at least one liquid crystal region having a size of 30% or more of the area of the picture element in one picture element. Display element. 8. The liquid crystal display device according to claim 6, wherein the surface free energy other than that of the picture element portion is 75 mN / m or less. 9. The difference between the surface free energy other than the picture element portion and the surface free energy of the picture element portion is 15 mN /
The liquid crystal display element according to claim 6, which is at least m. 10. A liquid crystal in which at least one substrate has two translucent substrates, and a composite having a space structure composed of a liquid crystal material and a polymer material is sandwiched between the two substrates. A method of manufacturing a liquid crystal display element, wherein a means for spatially controlling free energy of a system constituting the element is used as a means for controlling the spatial structure when the liquid crystal display element is produced. Method. 11. A means for controlling the interfacial free energy between the composite-side interface of at least one of the substrates and at least one of the composite constituent components is used as the means for spatially controlling the free energy. Claim 10
A method for manufacturing a liquid crystal display device according to item 1. 12. The method for manufacturing a liquid crystal display element according to claim 11, wherein a photosensitive resin is used for controlling the interface free energy. 13. The method for manufacturing a liquid crystal display device according to claim 11, wherein the surface of the substrate is modified to control the interface free energy. 14. The spatial control of the free energy is performed by controlling a distance of a void between the two substrates,
When the device is formed, the substrate is configured such that the surface area of the phase separation interface of the composite-constituting material in a controlled ordered structure is smaller than that in a disordered structure, The method for manufacturing a liquid crystal display device according to claim 10, wherein control of interfacial free energy of a phase separation interface is used. 15. At least one of the substrates has a plurality of regions having surface free energies different from each other, and the surface free energy of a region having a low surface free energy is 75 mN / m.
Below, or the surface energy difference between the plurality of regions is 15
A mixture containing at least mN / m or more and containing at least a liquid crystal material and a photopolymerizable material, which is injected between the two substrates, is irradiated with ultraviolet rays to cause phase separation accompanying the polymerization reaction, and to regularly A method for manufacturing a liquid crystal display device, wherein a polymer material and a liquid crystal material are distributed. 16. The method for producing a liquid crystal display element according to claim 15, wherein the liquid crystal material and the polymer material are phase-separated while at least one of a voltage and a magnetic field is applied. 17. The method for producing a liquid crystal display element according to claim 15, wherein the photopolymerizable material contains a liquid crystal polymerizable monomer. 18. The method for producing a liquid crystal display device according to claim 15, wherein the surface free energy of the photopolymerizable material is 40 mN / m or less. 19. A liquid crystal cell in which the mixture is filled between the two substrates is gradually heated to a temperature equal to or higher than the homogenizing temperature (T _iso ) of the mixture of the liquid crystal material and the photopolymerizable material to T _iso or less. The method for producing a liquid crystal display device according to claim 15, wherein the photopolymerizable material is cured after being cooled to deposit the liquid crystal material. 20. A method of manufacturing a liquid crystal display device, wherein a display medium having a plurality of liquid crystal regions surrounded by polymer walls is provided between a pair of substrates which are arranged to face each other. A step of forming a thin film on at least a part other than the base portion; a step of arranging the pair of substrates so that the thin films are disposed inside and facing each other with a gap therebetween; and a step of bonding a liquid crystal material to the gap. Injecting a mixed material containing at least a photopolymerizable material and a photopolymerization initiator, and irradiating the mixed material with ultraviolet rays to form a display medium composed of a plurality of liquid crystal regions surrounded by the polymer wall. And a method for manufacturing a liquid crystal display device including 21. When irradiating the mixed material with ultraviolet rays, a portion of the mixed material corresponding to the picture element portion is covered with a photomask, and the ultraviolet ray intensity of the portion covered with the photomask is irradiated. 21. The method for manufacturing a liquid crystal display device according to claim 20, wherein the intensity of ultraviolet rays is 80% or less. 22. The method for producing a liquid crystal display device according to claim 25, wherein the liquid crystal material and the polymer material are phase-separated while at least one of a voltage and a magnetic field is applied. 23. The method for producing a liquid crystal display element according to claim 20, wherein the photopolymerizable material contains a liquid crystal polymerizable monomer. 24. The method for producing a liquid crystal display device according to claim 20, wherein the surface free energy of the photopolymerizable material is 40 mN / m or less. 25. At least one of the substrates has a plurality of regions having surface free energies different from each other, and the surface free energy of the region having a low surface free energy is 75 mN / m.
Below, or the surface energy difference between the plurality of regions is 15
By heating a mixture containing at least a liquid crystal material and a thermopolymerizable material, which is injected between two substrates at mN / m or more, phase separation due to the polymerization reaction is caused to regularly polymer material. And a liquid crystal material are distributed, a method of manufacturing a liquid crystal display device. 26. The method of manufacturing a liquid crystal display device according to claim 25, wherein the liquid crystal material and the polymer material are phase-separated while at least one of a voltage and a magnetic field is applied. 27. The method for producing a liquid crystal display element according to claim 25, wherein the thermopolymerizable material contains a liquid crystal polymerizable monomer. 28. The method for producing a liquid crystal display device according to claim 25, wherein the surface free energy of the thermopolymerizable material is 40 mN / m or less. 29. A liquid crystal cell in which the mixture is filled between the two substrates is gradually heated to a temperature equal to or higher than the homogenizing temperature (T _iso ) of the mixture of the liquid crystal material and the thermopolymerizable material to T _iso or less. 26. The method for manufacturing a liquid crystal display element according to claim 25, wherein the thermopolymerizable material is cured after being cooled to deposit the liquid crystal material. 30. A method for manufacturing a liquid crystal display device, in which a liquid crystal material and a polymer material are sandwiched between a pair of substrates, at least one of which has electrodes formed thereon, is transparent, and a composite film comprising the liquid crystal material and the polymer material. A method of manufacturing a liquid crystal display device, wherein an interface of a substrate in contact with is modified. 31. The method of manufacturing a liquid crystal display element according to claim 30, wherein an alignment film is formed at an interface of a substrate in contact with the composite film made of the liquid crystal material and the polymer material. 32. The alignment film is subjected to rubbing treatment, and the surface of the alignment film is selectively modified by a rubbing strength difference caused by a height difference of the electrodes.
1. The method for manufacturing the liquid crystal display element according to 1. 33. The method of manufacturing a liquid crystal display element according to claim 31, wherein a film is formed on a specific region of the alignment film. 34. A step of forming an alignment film on a substrate on which the electrode is formed, a step of forming a film on a specific region of the alignment film, and a step of rubbing the alignment film and the film. The method for manufacturing a liquid crystal display element according to claim 30, comprising: