JP2000206532A - Manufacture of liquid crystal display element and liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a liquid crystal display element which is capable of providing an arbitrary pretilt angle using an alignment treatment with linearly polarized UV rays and at the same time, to provide a liquid crystal display element which does not give rise to a domain under voltage application so as not to produce a defective display. SOLUTION: On a surface of a substrate 3, tooth-shaped projecting and recessing scalene triangle shapes with an inclined angle corresponding to a desired pretilt angle &theta;and <=120 deg. apex angle are formed and an electrode and an alignment layer are formed thereon. The alignment layer is composed of an optical alignment polymer and is alignment treated by irradiating with linearly polarized UV rays so as to make a liquid crystal molecules' alignment direction after the alignment treatment be a direction crossing the tooth-shaped projecting and recessing shapes. Consequently adjustment of the pretilt angle, which is difficult with a optical alignment method, is made with ease and with high precision. Both a twisted nematic liquid crystal display element and a supertwisted nematic liquid crystal display element which requires a larger pretilt angle, formed with this method of alignment, exhibit high contrast and uniform displays.

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 of manufacturing the same, and more particularly, to a method of using a rubbing method for contacting liquid crystal molecules without using a rubbing method. The present invention relates to a liquid crystal display device having a liquid crystal alignment state and a method for manufacturing such a liquid crystal display device.

[0002]

2. Description of the Related Art The development of liquid crystal display elements and the improvement of their performance are:
It has greatly contributed to the expansion of the notebook PC market, and recently, notebook PCs accounted for almost 20% of all PCs. Liquid crystal display elements used in notebook personal computers are roughly classified into two types. one,
A twisted nematic liquid crystal device (hereinafter, TFT-) using a thin film transistor (hereinafter, TFT) for switching.
TN) and the other is a super twisted nematic (hereinafter, STN) liquid crystal display device. Among them, the former TFT-TN has become equivalent to a conventional cathode ray tube in terms of image quality, and the remaining problem is to manufacture a display element at low cost.

TN used for an active matrix type liquid crystal display panel or a small size liquid crystal display panel
In the case of the mold, the liquid crystal molecules are uniformly and unidirectionally oriented at a glass substrate interface at a predetermined pretilt angle with respect to the glass substrate, and are twisted by 90 ° between the upper and lower glass substrates. The 90 ° twist alignment state is generally obtained by rubbing an alignment film made of a polyimide thin film formed on a glass substrate in one direction using rayon cloth or the like, and arranging the upper and lower substrates so that the directions are orthogonal to each other. Can be

When a voltage is applied to the thus obtained TN type liquid crystal panel, the liquid crystal molecules which have been twisted by 90 ° begin to respond above the threshold voltage, the twisted alignment state is released, and the liquid crystal molecules become splay alignment state. The molecules are in a state where the major axis of the molecules rises with respect to the plane of the glass substrate.

[0005] If the rising characteristics with respect to the voltage are not uniform in the substrate surface, unevenness in brightness and color occurs in the display state, and the display quality is degraded. An important operation for determining the display quality is rubbing. The liquid crystal molecules are three-dimensionally oriented on the rubbed substrate surface. That is, the orientation is determined by the orientation orientation in the plane and the pretilt angle of the liquid crystal molecules with respect to the substrate. If the pretilt angle is too small, it is not clear which of the two ends of the molecule rises when the liquid crystal rises in response to an electric field, so that the rise occurs from both ends and a domain is generated. Although this pretilt angle largely depends on the alignment film material, it also changes depending on the rubbing conditions and the cured state of the alignment film. Therefore, it was extremely difficult to obtain an essentially uniform in-plane alignment state by the vague operation of rubbing.

[0006]

Therefore, in recent years, an alignment treatment method using linearly polarized ultraviolet rays has been proposed as a method which is not a rubbing method of contact type with an alignment film but a non-contact type and uniform treatment is expected. ing. In this method, as described in JP-A-6-289347,
As the alignment film, a polymer material that responds to light is used. When the linearly polarized ultraviolet light is irradiated on the alignment film, the polymer material reacts preferentially with respect to the polarization plane of the ultraviolet light.
As a result, a difference occurs in the regularity of molecules between the direction parallel to the polarization plane in the plane of the alignment film and the direction perpendicular to the plane of polarization. This difference is recognized by the liquid crystal molecules adjacent to the alignment film, and determines the orientation of the liquid crystal molecules. Whether the liquid crystal molecules are oriented parallel or perpendicular to the plane of linear polarization applied to the alignment film surface depends on the molecular structure of the alignment film and the form of the reaction.

However, the method of irradiating the photoreactive material with linearly polarized ultraviolet light alone cannot provide pretilt, another important factor imparted to the alignment of liquid crystal molecules by rubbing. If no pretilt is applied, domains are generated when a voltage is applied, resulting in display defects.

An object of the present invention is to provide a method of manufacturing a liquid crystal display device which can provide an arbitrary pretilt angle while using an alignment treatment using linearly polarized ultraviolet light. It is another object of the present invention to provide a method of manufacturing a liquid crystal display element capable of providing a liquid crystal display element in which domains are not generated when a voltage is applied and display defects are not generated as a result.

Another object of the present invention is to provide a liquid crystal display element in which domains are not generated when a voltage is applied, and as a result, display defects do not occur.

[0010]

Means for Solving the Problems To achieve the above object, the present invention has the following constitution.

That is, according to the method of manufacturing a liquid crystal display device of the present invention, two substrates having electrodes formed on the surface are disposed so that the electrode forming surfaces face each other, and a nematic liquid crystal layer is provided between the two substrates. A method for manufacturing a liquid crystal display element, comprising: forming at least one surface of the substrate on the liquid crystal layer side in a stripe shape having a saw-toothed uneven shape in a cross section; and linearly polarized ultraviolet light on the uneven shape. Forming an alignment film layer that has been subjected to an alignment treatment by irradiating the alignment film layer, the alignment film layer reacts with linearly polarized ultraviolet light, and after the reaction,
It is characterized in that the substrate is made of a material that exhibits anisotropy in the regularity of molecules in a direction parallel to the direction of linear polarization of the ultraviolet light and in a direction perpendicular to the direction of the linear polarization of the ultraviolet light.

According to the above configuration, the alignment film layer is formed in a saw-toothed uneven shape on the substrate, so that it is non-contact and does not involve charging. The tilt angle of the uneven shape can provide a stable pretilt angle to the liquid crystal molecules while taking advantage of the merit. Therefore, the liquid crystal display device obtained by the manufacturing method of the present invention does not generate a domain when a voltage is applied, and as a result, can perform a uniform and high-contrast display without causing display defects.

[0013] In the above configuration, it is preferable that the cross-sectional shape of the concave-convex shape is a trapezoidal triangle having a vertex angle of 120 ° or less. According to such a preferred configuration, it is possible to prevent the alignment of the liquid crystal molecules in contact with the alignment film layer from being disturbed, and to generate a uniform pretilt angle.

In the above structure, it is preferable to irradiate the linearly polarized ultraviolet light so that liquid crystal molecules in contact with the alignment film layer are aligned in a direction perpendicular to the stripe direction of the uneven shape. According to such a preferred configuration, an appropriate pretilt angle can be stably given to the liquid crystal molecules, so that the rising direction of the liquid crystal molecules at the time of applying a voltage is constant, and a liquid crystal display element free from display defects can be obtained.

Further, in the liquid crystal display device of the present invention, two substrates having electrodes formed on the surface are arranged so that the electrode forming surfaces face each other, and a nematic liquid crystal layer is provided between the two substrates. In at least one surface of the substrate on the side of the liquid crystal layer, a cross-sectional shape is formed in a saw-toothed uneven shape in a stripe shape, and further, an alignment film layer is formed on the uneven shape, The liquid crystal molecules in contact with the alignment film layer are aligned in a direction perpendicular to the stripe direction of the uneven shape.

According to the above configuration, the alignment film layer is formed on the uneven shape having a sawtooth cross section formed on the substrate,
Since the liquid crystal molecules in contact with the alignment film layer are oriented in the direction perpendicular to the stripe direction of the uneven shape, the liquid crystal molecules are given an appropriate pretilt angle by the inclination angle of the uneven shape. Therefore, no domain is generated at the time of applying the voltage, and as a result, a uniform and high-contrast display can be performed without causing display defects.

In the above structure, the alignment film layer reacts with the linearly polarized ultraviolet light, and after the reaction, the molecular regularity in the direction parallel to and perpendicular to the linearly polarized light direction of the ultraviolet light within the substrate surface. It is preferable that the material is made of a material exhibiting anisotropic properties. According to such a preferred configuration, the alignment treatment of the alignment film layer formed on the uneven shape,
It can be carried out without contact and without charging. In addition, the alignment direction of the liquid crystal molecules in contact with the alignment film layer in a plane parallel to the substrate can be easily adjusted to a desired direction.

In the above structure, it is preferable that the cross-sectional shape of the concavo-convex shape is a scalene triangle having a vertex angle of 120 ° or less. According to such a preferable configuration, it is possible to prevent the disorder of the alignment of the liquid crystal molecules in contact with the alignment film layer,
Since a uniform pretilt angle can be generated, a liquid crystal display element free from display defects can be obtained.

Further, the liquid crystal display device of the present invention can be used as a twisted nematic liquid crystal display device in which the twist angle of liquid crystal molecules between two substrates is approximately 90 degrees. In addition, the liquid crystal display element of the present invention has a super twisted nematic liquid crystal display in which the uneven shape and the alignment film layer are formed on both substrates, and the twist angle of liquid crystal molecules between the two substrates is 220 to 260 degrees. It can also be used as an element.

[0020]

FIG. 1 is a partially enlarged perspective view showing an example of a substrate according to the present invention in which saw-toothed irregularities are formed in stripes. As shown, on the surface of the substrate 3,
The concave-convex shape 1 having a sawtooth cross section in the thickness direction is repeatedly formed, and as a whole, they are arranged and formed in a periodic stripe shape. At least an electrode layer and an alignment film layer are formed on this uneven shape.

The alignment film layer reacts with the linearly polarized ultraviolet light, and after the reaction, exhibits the property of causing anisotropy in the regularity of molecules in the direction parallel to the direction of the linearly polarized light of the ultraviolet light and the direction perpendicular to the direction of the linearly polarized light of the ultraviolet light. It is formed using a material. After the alignment film material is provided on the uneven shape 1, linear alignment ultraviolet rays are applied to the alignment film surface so that the liquid crystal molecules are aligned in a direction perpendicular to the direction of the stripe of the uneven shape 1. Thereby, the alignment treatment can be performed in a non-contact manner without charging.

FIG. 2 is a side sectional view schematically showing the state of alignment of liquid crystal molecules in contact with the substrate of the present invention having an uneven surface. In FIG. 2, for simplification of the drawing, an electrode layer formed on the uneven shape 1,
The orientation film layer and the like are not shown. As shown in FIG. 2, the liquid crystal molecules 2 are given an orientation in a direction perpendicular to the stripe direction of the saw-toothed uneven shape 1. As a result, the liquid crystal molecules 2 are affected by the surface shape of the uneven shape 1, The longer side is the substrate 3
And is oriented in a direction restricted by the inclination angle θ formed with the surface of the substrate. That is, the tilt angle θ itself is the pretilt angle at the interface between the liquid crystal molecules 2 and the alignment film. Therefore, by optimizing the tilt angle θ according to the liquid crystal to be used, an optimal pretilt angle can be given to the liquid crystal molecules.

In order for the pretilt angle of the liquid crystal molecules 2 to be stably provided, the cross-sectional shape of the saw-toothed uneven shape 1 must be set to a vertex angle α
Is desirably a scalene triangle of 120 ° or less.
When the apex angle α is 120 ° or more, the influence of the inversely inclined surface having a cross-sectional shape becomes large, and the orientation may be disturbed.

It is preferable that the period of the stripe is 10 microns or less. If the pitch is larger than this, the surface irregularities become too large, and it is difficult to uniformly control the gap between the liquid crystal panels.

In the liquid crystal display device of the present invention using such a substrate, the pretilt angle, which was difficult to be stably provided only by the conventional photo-alignment method, is reduced by the inclination of the saw-toothed uneven shape 1 shown in FIG. It can be easily formed by corners. Since the control of the pretilt angle can be controlled by the surface shape of the concavo-convex shape 1, a stable pretilt angle is obtained, and the obtained pretilt angle is stable against a change in temperature.

The twisted nematic liquid crystal display device (TN-LCD) obtained according to the present invention is different from the twisted nematic liquid crystal device obtained by the rubbing alignment method in that the alignment direction is uniform over the entire surface. The feature is that there is no display unevenness.

In addition, a super twisted nematic liquid crystal display device (STN-LCD) requires a higher pretilt angle than a twisted nematic liquid crystal. Therefore, display abnormalities caused by the rubbing alignment method have been a problem. The super twisted nematic liquid crystal display device obtained by the present invention has a high pretilt angle, which was difficult to be stably provided only by the photo-alignment method. This is a great feature that there is no display unevenness in the form of stripes.

[0028]

An embodiment will be described below with reference to the drawings.

(Embodiment 1) As shown in FIG.
A transparent ITO electrode 4 having a length of 30 mm and a width of 45 mm was formed on a glass substrate 3a having a thickness of 1.1 mm and a width of 50 mm (upper substrate 10).

On another glass substrate 3b of the same size, a photoresist (TFR-910: manufactured by Tokyo Ohka) is applied, and by photolithography, saw-toothed irregularities as shown in FIG. Shape 1 is shown in FIG.
As shown in (1), a stripe was formed over the entire surface of the substrate (lower substrate 20). Such a saw-toothed uneven shape 1 was formed by exposing light whose intensity was periodically modulated by a light beam interference method onto a photoresist and adjusting development conditions. The pitch of the produced stripes of the uneven shape 1 is 2 μm.
m, the apex angle α (see FIG. 2) is approximately 100 °, the inclination angle θ of the long side with respect to the substrate 3b surface (see FIG. 2) is 4 °, and the uneven shape 1
The height from the base to the vertex of the triangle, which is a repeating unit of, was about 0.14 μm.

Thereafter, an ITO electrode 4 having the same shape as shown in FIG. 3 was formed on the uneven shape 1 arranged in a stripe shape. FIG. 5 is a schematic plan view thereof.

Next, on the two substrates of the same size,
A thin film 5 having a thickness of 0.05 μm made of polyvinyl cinnamate was formed by a spin coating method. Next, the two substrates on which the polyvinyl cinnamate film 5 was formed were irradiated with polarized ultraviolet light (UV) to perform an alignment treatment. As shown in FIG. 6, the polarization direction D of the linearly polarized ultraviolet light to be irradiated
_UV is parallel to the direction of the stripe for the lower substrate 20 having the saw-tooth unevenness 1 (FIG. 6 (A)), and the lower substrate 20 for the other substrate (upper substrate 10).
(FIG. 6B). In this embodiment, the irradiation conditions are as follows. In this embodiment, the ultraviolet light obtained by converting the light of a 200 W ultra-high pressure mercury lamp into linearly polarized light by a multilayer thin film element has an energy of 10 μm on the film surface.
mW / cm ² was set and irradiation was performed for 10 minutes.
In FIG. 6, D ₂₀ and D ₁₀ are the orientation directions of the liquid crystal molecules described later, which are in contact with the alignment film 5 on the lower substrate 20 and the upper substrate 10 thus formed.

Thus, the upper substrate 10 and the lower substrate 20 were obtained. FIG. 4 shows a cross-sectional structure of the lower substrate 20.

Next, as shown in FIG. 7, the upper substrate 10 was placed on the lower substrate 20 with the surface on which the electrodes 4 were formed facing each other. In addition,
FIG. 7 omits a stripe pattern formed by the concavo-convex shape 1 formed on the surface of the lower substrate 20 to simplify the drawing. At this time, as shown in FIG. 7, a thermosetting epoxy resin mixed with 2% by weight of plastic beads (manufactured by Sekisui Fine) having an average diameter of 5.2 μm is used as a sealing material 8 so as to keep the gap between both substrates at 5.0 μm as shown in FIG. Was placed. A seal 9 was provided in a part of the seal material 8, and after the seal material 8 was cured, liquid crystal was injected from the seal 9 by a vacuum injection method.
The nematic liquid crystal material used has a positive refractive index anisotropy (△
n), a Δn value of 0.098, and a mixed liquid crystal composition in which a chiral liquid crystal is mixed so that the helical pitch of the liquid crystal is 20 μm.

The orientation directions D ₁₀ and D ₂₀ of the liquid crystal molecules of the device thus obtained were substantially perpendicular to the polarization direction of the linearly polarized light UV. The pretilt angle of the liquid crystal molecules measured by a crystal rotation method was 4.3 °.

The element into which the liquid crystal is injected is sandwiched between two polarizing plates whose polarization directions are arranged at right angles to each other, so that the polarizing direction of the polarizing plate on the lower substrate 20 side having the striped unevenness is perpendicular to the stripe. As a result of the matching, a normally white display was obtained in which the light was transmitted in a light state with no voltage applied. When a voltage of a 60 Hz rectangular wave signal was applied between the upper and lower electrodes, the liquid crystal in the overlapping portion of the upper and lower electrodes was reoriented in the direction of the electric field, and a dark state was obtained. Brightness / darkness contrast is 220: 1, uniform TN without display unevenness
A liquid crystal display device was obtained.

(Embodiment 2) The same as in Embodiment 1, 40 m long
m, 50 mm wide glass substrate (thickness: 1.1 mm) 3b
And a photoresist (TFR-91)
0: manufactured by Tokyo Ohka Co., Ltd.), and by photolithography, a saw-toothed uneven shape 1 as shown in FIG. 4 was formed in stripes over the entire surface of the substrate as shown in FIG. Such a saw-toothed uneven shape 1 was formed by exposing light whose intensity was periodically modulated by a light beam interference method onto a photoresist and adjusting development conditions. The pitch of the stripes of the formed concavo-convex shape 1 is 2 μm, the apex angle α (see FIG. 2) is approximately 100 °, the inclination angle θ of the long side with respect to the substrate surface (see FIG. 2) is 6 °, and the repeating unit of the concavo-convex shape 1 The height from the base to the vertex of the triangle was about 0.2 μm.

After that, the ITO electrode 4 was formed on the concave-convex shape 1 arranged in a stripe shape in the same manner as the lower substrate 20 of the first embodiment. FIG. 5 is a schematic plan view thereof.

Next, a thickness of 0.05 μm of polyvinyl cinnamate was formed on the two substrates by spin coating.
m of the thin film 5 was formed. Next, the two substrates on which the polyvinyl cinnamate film 5 was formed were irradiated with polarized ultraviolet light (UV) to perform an alignment treatment. Polarization direction D _UV linearly polarized ultraviolet light to be irradiated, as well as the lower substrate 20 of Example 1 (see FIG. 6 (A)), were the same as the direction of the stripe serrated irregularities 1. The irradiation condition is 200 in this embodiment.
Ultraviolet light obtained by converting the light of a W ultra-high pressure mercury lamp into linearly polarized light by a multilayer thin-film element was set so that the energy on the film surface was 10 mW / cm ^2, and irradiated for 10 minutes.

As shown in FIG. 8, the two substrates thus obtained were used as upper substrate 21 and the other as lower substrate 22 so that the electrode forming surfaces were opposed to each other. In FIG. 8, as in FIG. 7, for simplification of the drawing, the stripe pattern formed by the uneven shape 1 formed on the surface of the lower substrate 22 is omitted. At this time, the upper and lower substrates 21 and 22 were arranged such that the angle formed by the stripe directions of the uneven shapes 1 was 240 °. The gap between both substrates is 6.0 μm.
As shown in FIG. 8, a thermosetting epoxy resin mixed with 2% by weight of plastic beads (manufactured by Sekisui Fine) having an average diameter of 6.2 μm was disposed as the sealing material 8 so as to maintain the sealing material 8. A seal 9 was provided in a part of the seal material 8, and after the seal material 8 was cured, liquid crystal was injected from the seal 9 by a vacuum injection method. The nematic liquid crystal material used has a positive refractive index anisotropy (Δn), a Δn value of 0.143, and a mixed liquid crystal composition in which a chiral liquid crystal is mixed so that the helical pitch of the liquid crystal is 20 μm. It is.

The orientation directions D ₂₁ and D ₂₂ of the liquid crystal molecules of the device thus obtained were substantially perpendicular to the polarization direction of the linearly polarized light UV. The pretilt angle measured by the crystal rotation method was 6.3 °.

The element into which the liquid crystal is injected is sandwiched between two polarizing plates whose polarization directions are perpendicular to each other, and the retardation value between the upper and lower polarizing plates and the panel is 430.
A normally black display in which a dark state is obtained with no voltage applied was obtained by disposing a retardation plate of nm. When a signal having a rectangular signal waveform of 1/300 duty and 1/18 bias was applied between the upper and lower electrodes, the contrast of light and dark was 5
At a ratio of 0: 1, a uniform STN liquid crystal display element having no display unevenness was obtained.

Comparative Example 1 In Comparative Example 1, the upper and lower substrates having the same shape and the same electrode pattern as in Example 1 were used except that no saw-tooth unevenness was formed on the surface of one substrate (lower substrate). The nematic liquid crystal material used was a mixed liquid crystal composition having the same Δn value of 0.098 as in Example 1. Example 1
The same orientation treatment as that described above was performed, and a device having the same configuration was manufactured.

The orientation direction of the liquid crystal molecules in this device was substantially perpendicular to the polarization direction of the linearly polarized light UV, and the pretilt angle was 0.3 ° or less as measured by the crystal rotation method.

The device into which the liquid crystal was injected was sandwiched between two polarizing plates whose polarization directions were orthogonal to each other, and the polarization direction of the polarizing plate on the lower substrate side was aligned so as to be perpendicular to the polarization direction of UV. Thus, a normally white display in which light was transmitted in a light state with no voltage applied was obtained. When a voltage of a rectangular wave signal of 60 Hz is applied between the upper and lower electrodes,
The liquid crystal in the overlapping portion of the upper and lower electrodes was re-oriented in the direction of the electric field, and a dark state was obtained. However, a large number of domains exhibiting a reverse tilt state in the dark state were observed, and the contrast between light and dark was 4
A TN liquid crystal display element having a low ratio of 0: 1 and exhibiting uneven display with much light leakage was obtained.

[0046]

According to the method of manufacturing a liquid crystal display element of the present invention, the alignment film layer is formed on the substrate in a saw-toothed uneven shape with a cross-sectional shape. While taking advantage of the photoalignment treatment method that does not involve
The inclination angle of the uneven shape can provide a stable pretilt angle to the liquid crystal molecules. Therefore, the liquid crystal display element obtained by the manufacturing method of the present invention has no domain when voltage is applied, and as a result, does not cause display defects.
Uniform and high-contrast display can be performed.

Further, according to the liquid crystal display device of the present invention, the alignment film layer is formed on the uneven shape having a sawtooth cross section formed on the substrate, and the liquid crystal molecules in contact with the alignment film layer have the uneven shape. , The liquid crystal molecules are given an appropriate pretilt angle by the inclination angle of the uneven shape. Therefore, there is no domain at the time of voltage application, and as a result, there is no display defect,
Uniform and high-contrast display can be performed.

[Brief description of the drawings]

FIG. 1 is a partially enlarged perspective view showing an example of a substrate of the present invention in which saw-toothed irregularities are formed in stripes.

FIG. 2 is a side cross-sectional view schematically showing a state of alignment of liquid crystal molecules in contact with a substrate of the present invention having an uneven surface formed thereon.

FIG. 3 is a plan view showing the arrangement of electrodes on an upper substrate used in the liquid crystal display device of Example 1 of the present invention.

FIG. 4 is an enlarged cross-sectional view in the thickness direction of a lower substrate used in the liquid crystal display device according to the first embodiment of the present invention.

FIG. 5 is a plan view showing an electrode arrangement on a lower substrate used in the liquid crystal display device of Example 1 of the present invention.

FIG. 6 is a diagram for explaining a polarization direction of linearly polarized ultraviolet light applied to the upper and lower substrates used in the liquid crystal display device of Example 1 of the present invention.

FIG. 7 is a plan view showing a state where the upper and lower substrates are bonded together in Example 1 of the present invention.

FIG. 8 is a plan view showing a state in which upper and lower substrates are bonded together in Example 2 of the present invention.

[Explanation of symbols]

1 serrated irregularities second liquid crystal molecules 3 substrate 3a, 3b glass substrate 4 ITO electrode 5 orientation film 8 sealing member 9 sealing 10 on the substrate 20 under the substrate 21 on the substrate 22 under the substrate D _UV linearly polarized light the polarization direction D ₁₀ of ultraviolet, D ₂₁ Alignment direction of liquid crystal molecules in contact with upper substrate D ₂₀ , D ₂₂ Alignment direction of liquid crystal molecules in contact with lower substrate

Claims (8)

[Claims] 1. Two substrates having electrodes formed on the surface thereof,
A method for manufacturing a liquid crystal display element having an electrode forming surface facing each other and having a nematic liquid crystal layer between both substrates, wherein at least one surface of the substrate on the liquid crystal layer side has a saw-tooth shape. Forming an alignment film layer that has been subjected to alignment treatment by irradiating linearly polarized ultraviolet light on the uneven shape, wherein the alignment film layer is formed of linearly polarized ultraviolet light. And a liquid crystal comprising a material exhibiting an anisotropy in the regularity of molecules in a direction parallel to the direction of linear polarization of the ultraviolet light and a direction perpendicular to the direction of linear polarization of the ultraviolet light on the surface of the substrate after the reaction. A method for manufacturing a display element. 2. The method according to claim 1, wherein the cross-sectional shape of the uneven shape is a vertex angle of 120.
方法 The method for manufacturing a liquid crystal display element according to claim 1, wherein the following is a scalene triangle. 3. The method for manufacturing a liquid crystal display device according to claim 1, wherein the linearly polarized ultraviolet light is irradiated such that liquid crystal molecules in contact with the alignment film layer are aligned in a direction perpendicular to the stripe direction of the uneven shape. . 4. The two substrates having electrodes formed on their surfaces,
A liquid crystal display element having a nematic liquid crystal layer disposed between the two substrates, wherein the electrode formation surfaces are opposed to each other, wherein at least one surface of the substrate on the side of the liquid crystal layer includes:
The cross-sectional shape is formed in a saw-toothed uneven shape in a stripe shape. Further, an alignment film layer is formed on the uneven shape, and liquid crystal molecules in contact with the alignment film layer are perpendicular to the stripe direction of the uneven shape. A liquid crystal display device characterized by being oriented in a direction. 5. The alignment film layer reacts with linearly polarized ultraviolet light, and after the reaction, anisotropy in molecular regularity in a direction parallel to and perpendicular to the linearly polarized light direction of the ultraviolet light within the substrate surface. 5. The liquid crystal display device according to claim 4, wherein the liquid crystal display device is made of a material exhibiting the property of causing the following. 6. The cross-sectional shape of the uneven shape has an apex angle of 120.
The liquid crystal display element according to claim 4, wherein the following is a scalene triangle. 7. The liquid crystal display device according to claim 4, wherein a twist angle of liquid crystal molecules between the two substrates is approximately 90 degrees, and the liquid crystal display device is a twisted nematic liquid crystal display device. 8. The method according to claim 1, wherein the uneven shape and the alignment film layer are the
The liquid crystal display device is a super twisted nematic liquid crystal display device, wherein the liquid crystal display device is formed on both of the two substrates, a twist angle of liquid crystal molecules between the two substrates is 220 to 260 degrees. Liquid crystal display element.