TWI499616B - The device and method of manufacturing the liquid crystal display - Google Patents

Description

Liquid crystal display element and method of manufacturing same

The present invention relates to a liquid crystal display element and a method of manufacturing the same.

The liquid crystal display element is formed by sandwiching a liquid crystal layer between a pair of substrates, and sealing the liquid crystal of the liquid crystal layer in a fixed direction. The alignment of the liquid crystal is achieved by providing a liquid crystal alignment film having a liquid crystal alignment control capability on the surface of the substrate. In the liquid crystal display device, the liquid crystal is responsive to a voltage applied to an electrode disposed between the substrate and the liquid crystal alignment film, and the alignment of the liquid crystal is changed to display an image desired in the image forming region. Moreover, the liquid crystal display element can provide a thin and lightweight high-quality display device.

In the manufacture of a liquid crystal display element, a method of sealing a liquid crystal which is a liquid crystal layer between a pair of substrates is to use a frame-shaped sealing material disposed on a substrate. Further, liquid crystal is injected into the inside of the frame-shaped sealing material by a vacuum injection method, a dropping injection method, or the like, and a liquid crystal layer is sealed between the substrates. In the liquid crystal injection method, a method which is considered to be preferable in recent years is a dropping injection method from the viewpoint of effectively reducing the amount of liquid crystal used (refer to Patent Document 1).

In the dropping method, the ultraviolet curable sealing material is formed in a frame shape around the substrate, and the liquid crystal is dropped on the substrate in the frame of the sealing material in a vacuum environment, and bonded to the substrate having the liquid crystal dropped thereon. The substrate on the other side. Next, it returns to the atmosphere, and the liquid crystal between the two substrates that have been bonded is diffused by atmospheric pressure. Then, the sealing material is irradiated with ultraviolet rays to cure the sealing material, and the liquid crystal is sealed.

Further, in the production of the liquid crystal display device, as a method of aligning the liquid crystal of the liquid crystal layer in a fixed direction, as described above, a method of providing a liquid crystal alignment film having a liquid crystal alignment control capability on the surface of the substrate is used. The liquid crystal alignment film is formed by subjecting a polymer film such as polyimide or the like formed on a substrate to an alignment treatment such as a rubbing treatment or a photo-alignment treatment of irradiated ultraviolet rays.

The rubbing treatment for the liquid crystal alignment film refers to an organic film such as polyimide or the like on the substrate, and the surface thereof is wiped (frictionally) in a fixed direction with a cloth such as cotton, nylon or polyester to align the liquid crystal. The direction of the wiping direction (friction direction). Since the rubbing treatment can realize a relatively stable liquid crystal alignment state relatively easily, it is used in a manufacturing process of a conventional liquid crystal display element.

However, the rubbing method of wiping the surface of the liquid crystal alignment film composed of polyimide or the like has a problem that dust or static electricity is generated. In addition, due to the high definition of the liquid crystal cell elements in recent years, or the irregularities caused by the electrodes disposed on the substrate or the switching active elements for driving the liquid crystal, the surface of the alignment film cannot be uniformly wiped with the cloth, resulting in failure to realize Liquid crystal alignment.

Therefore, in recent years, light aligning processing which does not perform rubbing has been widely studied (refer to Patent Document 2).

There are various methods for photo-alignment processing, in which anisotropic property is formed in an organic film constituting a liquid crystal alignment film by linearly polarized light or targeted light, and liquid crystal is aligned according to the anisotropy. It is suitable to use ultraviolet rays as a light system. This light alignment treatment does not require rubbing, and it is not necessary to cause dust or the like to form a liquid crystal display element, and achieve desired liquid crystal alignment.

[Advanced technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 11-109388

[Patent Document 2] Japanese Patent No. 4504665

As described above, the liquid crystal display element can provide a thin, lightweight, high-quality display device. In the manufacture thereof, the main steps include the step of encapsulating the liquid crystal material between the substrates, or the alignment processing step of the liquid crystal alignment. Further, in any of these cases, in recent years, the steps of irradiating light such as ultraviolet rays have been actively utilized. The step of using light irradiation as described above is a problem that can effectively improve the manufacturing steps of the conventional vacuum injection method or the rubbing treatment, and improve the production efficiency or the manufacturing yield.

However, on the other hand, in the manufacturing step of the liquid crystal display element, the irradiation of light, in particular, the irradiation of ultraviolet light, is performed. In this case, the charge retention characteristics of the liquid crystal display element are lowered, and the display quality is lowered.

For example, in the implementation of liquid crystal injection. In the case of the dropping method in the sealing, when the sealing material is irradiated with ultraviolet rays, the liquid crystal alignment film in the image forming region may be irradiated with ultraviolet rays. In this case, the liquid crystal display element produced has a problem that the charge retention characteristics are lowered and the display quality of the image is lowered.

Further, when the photo-alignment treatment is performed, the use of the polarized ultraviolet ray may impart a liquid crystal alignment control ability to the liquid crystal alignment film. In this case, the liquid crystal display element manufactured can realize the alignment of the liquid crystal, but the charge retention characteristics are lowered, and the display quality of the image is lowered.

Therefore, it is required to produce a liquid crystal display element which does not deteriorate in charge retention characteristics, such as a drop-injection method or a photo-alignment process which has been widely studied in recent years, and is performed by a step of performing light irradiation treatment with ultraviolet rays. .

Therefore, the present invention has an object of providing a liquid crystal display element in which reduction in display quality is suppressed even when light irradiation treatment by ultraviolet light is applied.

Further, the present invention has an object of providing a method for producing a liquid crystal display element of a liquid crystal display element in which a reduction in the quality of the display is suppressed by a light irradiation treatment by ultraviolet light.

Further objects and advantages of the present invention are apparent from the following description.

According to a first aspect of the invention, there is provided a liquid crystal display device comprising: a liquid crystal alignment film in a region where a pixel is formed, and a region in which the formation region of the pixel is irradiated with ultraviolet rays, wherein the liquid crystal alignment film is selected from the group consisting of A polyimide precursor formed of a compound represented by the following formula (1) and at least one polymer of a polyimine obtained by imidating the oxime.

In the first aspect of the invention, the liquid crystal alignment film contains a compound selected from the group consisting of the compound represented by the above formula (1) and the compound represented by the following formula (AM) (excluding the compound represented by the above formula (1)) Preferably, the formed polyimide precursor and at least one polymer of the polyimine obtained by imidating the oxime are preferred.

(In the formula (AM), Y ₁ is a divalent organic group, and two or more kinds may be mixed. Further, in the formula (AM), R ¹ and R ^{2 each} represent a hydrogen atom or a monovalent organic group.

In the first aspect of the invention, the liquid crystal alignment film contains a polyimine precursor formed from at least one selected from the group consisting of compounds represented by the following formulas (CB1) to (CB5), and the quinone imine. A polymer of at least one of the obtained polyimines is preferred.

(In the formula (CB1) to (CB5), Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms, and contains a non-aromatic cyclic hydrocarbon group having 4 to 6 carbon atoms. In the formulae (CB4) and (CB5) R ³ represents a carbon number of 1 to 5, preferably an alkyl group having 1 to 2 carbon atoms.)

A second aspect of the present invention relates to a method of producing a liquid crystal display device, which is characterized in that a liquid crystal display element having a liquid crystal layer and a liquid crystal alignment film is formed in a region where a pixel is formed, and has a feature of: a liquid crystal alignment film forming step of forming the liquid crystal alignment film in the formation region of the pixel, and a step of irradiating the formation region of the pixel with ultraviolet light after the liquid crystal alignment film forming step; wherein the liquid crystal alignment film includes The polyimine precursor formed from the compound represented by the following formula (1) and at least one polymer of the polyimine obtained by imidating the oxime.

In the second aspect of the invention, the liquid crystal alignment film contains a compound selected from the group consisting of the compound represented by the above formula (1) and the compound represented by the following formula (AM) (excluding the compound represented by the above formula (1)) Preferably, the formed polyimide precursor and at least one polymer of the polyimine obtained by imidating the oxime are preferred.

(In the formula (AM), Y ₁ is a divalent organic group, and two or more kinds may be mixed. Further, in the formula (AM), R ¹ and R ^{2 each} represent a hydrogen atom or a monovalent organic group.

In a second aspect of the invention, the liquid crystal alignment film contains a polyimine precursor formed from at least one selected from the group consisting of compounds represented by the following formulas (CB1) to (CB5) and the quinone imine. A polymer of at least one of the obtained polyimines is preferred.

(In the formula (CB1) to (CB5), Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms, and contains a non-aromatic cyclic hydrocarbon group having 4 to 6 carbon atoms. In the formulae (CB4) and (CB5) R ³ represents a carbon number of 1 to 5, preferably an alkyl group having 1 to 2 carbon atoms.)

In a second aspect of the present invention, a sealing forming step of forming a sealing material around a formation region of a pixel after the liquid crystal alignment film forming step is performed, and the light irradiation step is such that the sealing material in the sealing forming step is hard. The steps are better.

In the second aspect of the present invention, the step of aligning the liquid crystal alignment film in the light irradiation step is preferred.

In a second aspect of the present invention, after the liquid crystal alignment film forming step, the liquid crystal layer is formed on the formation region of the pixel, and the light irradiation step drives the liquid crystal of the liquid crystal layer while forming the pixel. The step of irradiating ultraviolet rays in the area is preferred.

In the second aspect of the present invention, the liquid crystal layer contains a liquid crystal and a photopolymerizable compound, and the light irradiation step is preferably a step of polymerizing the photopolymerizable compound of the liquid crystal layer present on the formation region of the pixel. .

In the second aspect of the present invention, after the liquid crystal alignment film forming step, the liquid crystal layer is formed in the formation region of the pixel, and the light irradiation step drives the liquid crystal of the liquid crystal layer while forming the region of the pixel. The step of irradiating ultraviolet rays is preferred.

According to the first aspect of the present invention, it is possible to provide a liquid crystal display device which is manufactured by performing a light irradiation treatment by irradiation with ultraviolet rays and which exhibits a reduction in the quality of the display.

According to the second aspect of the present invention, it is possible to provide a method of manufacturing a liquid crystal display element for producing a liquid crystal display element which is subjected to light irradiation treatment by irradiation of ultraviolet light and which exhibits a reduction in the quality of the display.

1‧‧‧Liquid display components

2‧‧‧TFT substrate

3‧‧‧CF substrate

4‧‧‧Liquid layer

5, 15‧‧‧ substrate

6‧‧‧ pixel electrodes

7‧‧‧CF layer

8‧‧‧Protective layer

9‧‧‧Colored layer

10‧‧‧Black matrix

11‧‧‧Common electrode

12‧‧‧Liquid alignment film

16‧‧‧ Sealing material

17‧‧‧Polar plate

Fig. 1 is a cross-sectional view schematically showing the structure of a liquid crystal display element according to an embodiment of the present invention.

In the manufacture of the liquid crystal display element, as described above, the main steps include a step of sealing the liquid crystal between the substrates, or an alignment processing step of the liquid crystal alignment film for liquid crystal alignment. In such a procedure, light is used, and in particular, irradiation with visible light or ultraviolet light is used to harden the photocurable sealing material, or light alignment treatment of the liquid crystal alignment film is performed, and the desired effect can be achieved.

Further, a liquid crystal display device of a PSA (Polymer Sustained Alignment) type uses a small amount of a liquid crystal to which a photopolymerizable compound (typically 0.2% by weight to 1% by weight) is added, and is applied between electrodes having two substrates holding the liquid crystal. Irradiation of ultraviolet light in the state of voltage. As a result, in the liquid crystal display device of the PSA type, the photopolymerizable compound is reacted, polymerized, and crosslinked by the ultraviolet irradiation treatment, whereby the response speed of the liquid crystal display element is increased.

In addition, a liquid crystal display element of the type manufactured by irradiating ultraviolet rays with a voltage applied between electrodes of the two substrates holding liquid crystals (hereinafter, simply referred to as ultraviolet irradiation method in the present description). The liquid crystal display element of the ultraviolet irradiation method is a liquid crystal display element of a vertical alignment VA (Vertical Alignment) mode. As described above, it is produced by irradiating ultraviolet rays with a voltage applied between the electrodes of the two substrates holding the liquid crystal. In the liquid crystal display element of the ultraviolet irradiation method, a photopolymerizable compound may be added in a small amount to the liquid crystal. Further, the liquid crystal display element of the ultraviolet irradiation method can achieve excellent response characteristics of the liquid crystal.

As described above, the liquid crystal display element can achieve desired characteristics by including light irradiation, particularly ultraviolet irradiation treatment, in the manufacturing step thereof. On the other hand, however, it is also known that there is a problem. In other words, in the conventional liquid crystal display device, there is a case where a pixel is formed in a region where the image is displayed, and light is received, and in particular, ultraviolet rays are irradiated to deteriorate the characteristics. Specifically, there is a case where the charge retention characteristics (for example, the charge retention ratio) are lowered by irradiation with ultraviolet rays, or the residual DC characteristics are lowered.

Therefore, as a result of intensive studies, the present inventors have found that the problem can be effectively solved by optimizing the structure of the liquid crystal alignment film of the liquid crystal display element.

In the liquid crystal display device, as described above, the liquid crystal alignment film for liquid crystal alignment is often a polyimide film having high heat resistance and high strength.

Further, when a polyimide film which is a liquid crystal alignment film is formed on a substrate constituting a liquid crystal display element, a method of using a liquid crystal alignment agent as follows is suitably employed.

As a method of the present invention, a liquid crystal alignment agent containing a polyimide precursor such as polyglycine is prepared, and a coating film formed by using the obtained liquid crystal alignment agent is known, and the coating film is formed on the substrate. A method of obtaining a polyimide film by amination. Moreover, as another method, it is possible to imidize it in advance. A method in which a polyimide film is dissolved in a solvent to prepare a solvent-soluble liquid crystal alignment agent, and then a coating film is formed using the liquid crystal alignment agent to obtain a polyimide film.

The inventors of the present invention have found that by optimizing the molecular structure of the polyimine-based liquid crystal alignment film, it is possible to reduce the problem caused by the above-mentioned light, particularly ultraviolet light irradiation. In other words, the inventors of the present invention have obtained a liquid crystal display element which is formed by irradiating light, particularly ultraviolet rays, through a region where a pixel is formed, and has a polyimine precursor selected from an optimum structure and The liquid crystal alignment element of at least one polymer of a polyamidimide obtained by amination, which is a liquid crystal display element whose performance is deteriorated by irradiation with light, especially ultraviolet rays, has completed the present invention.

Hereinafter, embodiments of the present invention will be described.

Embodiment 1

A liquid crystal display element according to a first embodiment of the present invention will be described with reference to the drawings.

As an example of the liquid crystal display element of the present embodiment, a color liquid crystal display element of a TN (Twisted Nematic) mode can be used.

In this case, the liquid crystal display element of the present embodiment has, for example, a TFT having a TFT substrate on which a thin film transistor (TFT) is disposed, and a color filter layer (hereinafter also referred to as a CF layer). The substrate is provided with a liquid crystal layer, and a sealing material is disposed around the pixel formation region where the image is formed, and the substrate is fixed between the substrates.

Hereinafter, the structure of the liquid crystal display element of this embodiment will be described in more detail.

Fig. 1 is a cross-sectional view schematically showing the structure of a liquid crystal display element of the present embodiment.

The liquid crystal display element 1 shown in Fig. 1 is an example of a liquid crystal display element according to the first embodiment of the present invention, and as described above, a transmissive TN mode liquid crystal display element driven by a TFT can be used. This liquid crystal display element 1 is configured by sandwiching the liquid crystal layer 4 from the TFT substrate 2 and the CF substrate 3 including the CF layer 7.

As shown in FIG. 1, the TFT substrate 2 of the liquid crystal display element 1 is formed on the liquid crystal layer 4 side of the transparent substrate 5, and is formed in a matrix form by a TFT (not shown) and a transparent pixel electrode 6 made of ITO or the like. . For example, the TFT substrate 2 has a plurality of gate lines (not shown) which are provided in parallel with the substrate 5, and a gate insulating film (not shown) which is provided to cover the gate lines, and each of the gate insulating film and the gate insulating film. a plurality of unillustrated source lines, a cross-section of each of the gate lines and each of the source lines, and a plurality of TFTs and covers respectively disposed on each of the pixels, in which the gate lines are in the direction of a right angle and extend in parallel with each other. Each of the TFTs and the interlayer insulating film provided in each of the source lines is formed on the interlayer insulating film to form a plurality of pixel electrodes 6 which are connected in a matrix and are connected to the respective TFTs.

The CF substrate 3 of the liquid crystal display element 1 is formed on the liquid crystal layer 4 side of the transparent substrate 15, and the CF layer 7 and the protective layer 8 are disposed. The CF layer 7 has a red, green, and blue coloring layer 9 disposed at a position facing the pixel electrode 6 of the TFT substrate 2, and a black matrix 10 disposed between the colored layers 9 to shield light from light. And constitute. A transparent common electrode 11 made of ITO or the like is disposed on the protective layer 8 on the CF layer 7 of the CF substrate 3.

The liquid crystal alignment film 12 is provided on the surface of the TFT substrate 2 and the CF substrate 3 which are in contact with the liquid crystal layer 4, respectively. The liquid crystal alignment film 12 can be formed into a liquid crystal alignment film 12 which is formed using a polyimide film of a desired structure as described in detail below. In the liquid crystal display element 1, the liquid crystal alignment film 12 can be uniformly aligned in the liquid crystal layer 4 held by the TFT substrate 2 and the CF substrate 3, for example, by performing an alignment treatment such as rubbing treatment.

The liquid crystal display element 1 of the present embodiment can be made into a TN mode liquid crystal display element. The liquid crystal layer 4 is composed of a nematic liquid crystal, and exhibits a 90-degree alignment state between the TFT substrate 2 and the CF substrate 3 by the action of the liquid crystal alignment film 12.

In the TFT substrate 2 and the CF substrate 3, a polarizing plate 17 is disposed on each of the surfaces on the outer side opposite to the liquid crystal layer 4 side. The interval (also referred to as a gap) between the TFT substrate 2 and the CF substrate 3 is preferably 1 μm to 20 μm, and the gap is maintained by the sealing material 16 provided on the peripheral portion of the arrangement region of the pixel electrode 6.

The sealing material 16 is provided in a rectangular frame shape so as to surround the periphery of the formation region where the pixel electrodes 6 are disposed and the pixels for displaying the image are displayed. The frame width of the sealing material 16 is not particularly limited, and may be, for example, 0.5 mm or more and 2.0 mm or less. As the sealing material for forming the sealing material 16, for example, an ultraviolet curable resin such as an acrylic resin, a methyl ester resin, a polyester resin, or an epoxy resin can be used. These resins may be used alone or in combination of two or more.

Next, the liquid crystal display element 1 is a sealing material 16 such as a system. A user who uses an ultraviolet curable resin and is cured by ultraviolet rays. Therefore, the liquid crystal display element 1 is provided in the region where the pixels are formed, and the ultraviolet rays for curing the sealing material 16 are also irradiated in the same manner.

Thereby, the liquid crystal display element 1 which irradiates ultraviolet rays in the formation region of the pixel is composed of one pixel per pixel element 6, and a voltage of a predetermined magnitude is applied to the liquid crystal layer 4 in each pixel. On the other hand, the liquid crystal alignment state of the liquid crystal layer 4 is changed, and for example, the transmittance of visible light incident by a backlight (not shown) is adjusted to display an image.

The liquid crystal display element 1 having the above structure can be produced by performing as follows.

First, the TFT substrate 2 of the above configuration is prepared. The TFT substrate 2 is manufactured by, for example, a substrate 5 made of a transparent glass substrate or the like, and is formed by forming a TFT or various electrodes including the pixel electrode 6 in accordance with a known method. Then, the liquid crystal alignment film 12 is formed on the TFT substrate 2. Details of the liquid crystal alignment film 12 and a method of forming the same will be described later in detail.

Thereafter, the CF substrate 3 of the above configuration is prepared. The CF substrate 3 is formed by, for example, patterning a CF layer 7 having a colored layer 9 and a black matrix 10, a common electrode 11, and the like on a substrate 15 made of a transparent glass substrate or the like. Further, a liquid crystal alignment film 12 is formed on the surface of the common electrode 11. Further, the black matrix is made of a metal material such as Ta (钽), Cr (chromium), Mo (molybdenum), Ni (nickel), Ti (titanium), Cu (copper), or Al (aluminum), and is dispersed with carbon. The resin material of the black pigment or the coloring layer of the plurality of colors each having light transmittance is formed by laminating a resin material or the like.

Next, a pixel electrode 6 is formed on the TFT substrate 2. The ultraviolet curable sealing material is formed around the formation region of the pixel, according to the method of the dispenser, or the method of printing into a desired shape, or by the spin coating method, and then by the photolithography method. The sealing method 16 is formed in a frame shape by a method or the like. Next, in a vacuum environment, liquid crystal is dropped onto the TFT substrate 2 in the frame of the sealing material 16, and the TFT substrate 2 on which the liquid crystal is dropped is bonded to the CF substrate 3 at the same time. Then, the TFT substrate 2 and the CF substrate 3 are returned to the atmosphere in this state, and the liquid crystal between the bonded TFT2 substrate and the CF substrate 3 is diffused by atmospheric pressure to form the liquid crystal layer 4. Further, the sealing material 16 is irradiated with ultraviolet rays to cure the sealing material 16. Thereafter, the polarizing plate 17 is placed on the outer side surface of the TFT substrate 2 opposite to the liquid crystal layer 4 of the CF substrate 3 to form the liquid crystal display element 1.

Therefore, in the manufacture of the liquid crystal display element 1 of the present embodiment, the step of irradiating the ultraviolet light is a step of curing the sealing material 16, and is also a step of fixing the TFT substrate 2 and the CF substrate 3 to each other. The irradiation light system has a wavelength characteristic suitable for curing the sealing material 16, and the wavelength system can be set to ultraviolet rays of 200 nm to 400 nm. Further, the amount of ultraviolet rays to be irradiated is preferably selected in an amount suitable for curing the sealing material.

Here, the light irradiation step of curing the sealing material 16 by the ultraviolet irradiation treatment is a formation region of the pixel in which the pixel electrode 6, the liquid crystal alignment film 12, the liquid crystal layer 4, and the like are disposed together with the sealing material 16. Irradiation of ultraviolet light. For example, an additional means for providing a mask having a predetermined shape, such as the liquid crystal alignment film 12 or the like in the region where the pixels are formed, is not provided. Therefore, the light irradiation step is more simple and does not distinguish The step of forming the region of the sealing member 16 and the region where the pixel is formed, and irradiating the entire region with ultraviolet rays to harden the sealing member 16.

However, the liquid crystal display element 1 of the present embodiment is configured by using the liquid crystal alignment film 12 containing a polyimide film of a structure described later. Therefore, for example, when the sealing member 16 is hardened, even if it is irradiated with ultraviolet rays in the formation region of the pixel, the deterioration of its performance is suppressed. Therefore, even when the liquid crystal display element 1 of the present embodiment is irradiated with ultraviolet rays through the formation region of the pixel, it is possible to suppress performance deterioration due to ultraviolet irradiation which has been conventionally considered as a problem. In other words, according to the present embodiment, it is possible to provide the liquid crystal display element 1 which is produced by the light irradiation treatment using ultraviolet light, and which suppresses the deterioration of the display quality.

Further, in the liquid crystal display element 1 of the present embodiment, a visible light curing type sealing material can be used when the sealing material 16 is formed. For example, a photocurable resin which is cured by irradiating light energy of visible light, such as an acrylic resin, a methacrylic resin, an epoxy resin, and a polyoxyxylene resin, can be used. In this case, the liquid crystal display element 1 of the present embodiment is configured by using the liquid crystal alignment film 12 of a polyimide film having a specific structure to be described later. For example, even in the case where the sealing material 16 is cured, in the region where the pixel is formed, By being exposed to visible light, deterioration in performance can still be suppressed. Therefore, even when the liquid crystal display element 1 of the present embodiment is formed by the step of irradiating visible light to the region where the pixels are formed, deterioration of performance due to visible light irradiation can be suppressed.

Further, the liquid crystal display element of the present embodiment can be made STN (Super Twisted) in addition to the TN mode described above. Liquid crystal mode such as Nematic) mode, IPS (In-Planes Switching) mode, VA (Vertical Alignment) mode, or OCB (Optically Compensated Birefringence) mode. In other cases, the TFT substrate or the CF substrate is different from the example shown in Fig. 1 and can be formed into a known structure suitable for each liquid crystal mode.

In the liquid crystal display device of the present embodiment, which is manufactured by irradiation with ultraviolet rays, the display quality is suppressed, and the liquid crystal alignment film is an important component. . Therefore, the main components of the liquid crystal display device of the present embodiment will be described next, and the liquid crystal alignment film can be effectively reduced in performance even if it is irradiated with light such as visible light or ultraviolet light.

Further, although the liquid crystal display element 1 of the present embodiment shown in FIG. 1 is a TN mode liquid crystal display element, this is only an example of the embodiment, and the liquid crystal alignment film described below is also suitable for the IPS mode or The liquid crystal alignment film of the liquid crystal display element of the present embodiment, such as the VA mode, will be described.

The liquid crystal alignment film of the present embodiment constituting the liquid crystal display device of the present embodiment is formed into a liquid crystal alignment comprising at least one polymer selected from the group consisting of a polyimide precursor and a polyimide obtained by imidating the oxime. The film is better. By including such a polymer, the liquid crystal alignment film of the present embodiment has high heat resistance and the like, and has excellent durability.

Further, the liquid crystal alignment film of the present embodiment can effectively reduce the deterioration of the performance of the liquid crystal display element by the liquid crystal alignment film even if it is irradiated with ultraviolet rays. Formed on a substrate such as a TFT substrate or a CF substrate as described above When a liquid crystal alignment film containing a polymer such as polyimide or the like is used, a method using a liquid crystal alignment agent is suitable. The liquid crystal alignment agent has at least one polymer having a polyimine precursor selected from the group consisting of a reaction of a diamine compound and a tetracarboxylic acid derivative, and a polyimine obtained by imidating the oxime. The composition is better. Further, a coating film of a liquid crystal alignment agent is heated on a substrate such as a TFT substrate or a CF substrate to form a polymer film such as polyimide, and a liquid crystal alignment film can be formed by performing necessary alignment treatment.

Therefore, the liquid crystal alignment film of the present embodiment is preferably formed by using the liquid crystal alignment agent of the present embodiment. Further, the liquid crystal alignment agent of the present embodiment is a liquid crystal alignment film containing at least one polymer selected from the group consisting of a polyimide precursor and a polyimine obtained by imidating the oxime, and is a liquid crystal alignment film capable of forming the above characteristics. The structure of the polymer is optimized.

As a result, the structural characteristics of the polymer such as the polyimide precursor and the polyimine contained in the liquid crystal alignment agent can provide a liquid crystal alignment film which can effectively reduce performance deterioration even when irradiated with ultraviolet rays.

The polyimine precursor which may be contained in the liquid crystal alignment agent is obtained by reacting a diamine compound with a tetracarboxylic acid derivative as described above, and the polyamidene is a polyimine precursor which is subjected to a ruthenium imine. Get it. The polyimine precursor contained in the liquid crystal alignment agent of the present embodiment is preferably a diamine compound selected from a specific structure in order to realize the desired structure, and is preferably used for its synthesis.

In other words, the liquid crystal alignment agent of the present embodiment contains a polyimine precursor selected from the group consisting of a diamine compound having a specific structure and a tetracarboxylic acid derivative, and is obtained by imidating the ruthenium imide. Polyimine At least one polymer is provided, and the liquid crystal alignment film of the present embodiment can be provided.

Next, the polyimine precursor which can be contained in the liquid crystal alignment agent of the present embodiment and the diamine compound and the tetracarboxylic acid derivative which are specific structures for forming polyimine are described in more detail. Hereinafter, the polyimine precursor and the polyimine will be described in more detail, and the liquid crystal alignment agent of the present embodiment containing the same, and the liquid crystal alignment film of the present embodiment using the same will be described in more detail.

Further, in the present invention, the polyimine precursor system includes polylysine, polyphthalate, and the like.

<Diamine compound>

As the diamine compound having a specific structure suitable for the synthesis of the polyimine precursor contained in the liquid crystal alignment agent of the present embodiment for use in the liquid crystal alignment film of the present embodiment, the following formula (1) can be used. Expressed as a compound.

As a polyimine precursor and a polyfluorene which are reacted with a tetracarboxylic acid derivative and which can be contained in the liquid crystal alignment agent of the present embodiment As the diamine used for the imine, only the diamine compound represented by the above formula (1) may be used alone. Further, the compound represented by the above formula (1) may be used in combination with other diamine compounds represented by the following formula (AM) described below, in addition to the diamine compound represented by the above formula (1). .

<Other diamine compounds>

In order to synthesize the polyimine precursor and the polyimine which may be contained in the liquid crystal alignment agent of the present embodiment, the compound represented by the above formula (1) and the above formula (1) may be used as described above. Other diamine compounds represented by the following formula (AM) other than the diamine compound shown below are used in combination.

In the above formula (AM), Y ₁ is a divalent organic group, and two or more kinds may be mixed. Further, in the above formula (AM), R ¹ and R ^{2 each} represent a hydrogen atom or a monovalent organic group.

More specifically, in the above formula (AM), R ¹ to R ² each independently represent a hydrogen atom or an alkyl group, an alkenyl group or an alkynyl group having 1 to 10 carbon atoms which may have a substituent.

In the above formula (AM), R ¹ and R ² are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, an alkenyl group or an alkynyl group as a substituent; Specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a t-butyl group, a hexyl group, an octyl group, a decyl group, a cyclopentyl group, a cyclohexyl group, a bicyclohexyl group and the like. The above-mentioned alkenyl group is a structure in which one or more CH-CH structures present in the above alkyl group are replaced by a C=C structure, and more specifically, examples thereof include a vinyl group, an allyl group, and a 1-propene group. A group, an isopropenyl group, a 2-butenyl group, a 1,3-butadienyl group, a 2-pentenyl group, a 2-hexenyl group, a cyclopropenyl group, a cyclopentenyl group, a cyclohexenyl group or the like. The alkynyl group may be one in which one or more CH ₂ -CH ₂ structures are substituted with a C≡C structure, and more specifically, an ethynyl group or a 1-propynyl group may be mentioned. 2-propynyl and the like.

The above-mentioned alkyl group, alkenyl group or alkynyl group may have a substituent even if it has a carbon number of 1 to 10 as a whole, and may further form a ring structure by a substituent. Further, the formation of a ring structure by a substituent means that the substituents are bonded to each other or a part of the substituent to form a ring structure.

In this case, examples of the substituent include halogen group, hydroxyl group, mercapto group, nitro group, aryl group, organooxy group, organic sulfur group, organic mercapto group, mercapto group, ester group, thioester group, phosphate group, Amidino, alkyl, alkenyl, alkynyl.

The halogen group as the above substituent may, for example, be a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

The aryl group as the above substituent may, for example, be a phenyl group. The aryl group may also be substituted with other substituents as described above.

As the organooxy group of the above substituent, a structure represented by O-R can be exhibited. The R may be the same or different, and may be exemplified as described above. Alkyl, alkenyl, alkynyl, aryl, and the like. These Rs may also be substituted by the aforementioned substituents. Specific examples of the organic oxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, and an octyloxy group.

As the organothio group of the above substituent, a structure represented by -S-R can be exhibited. As such R, an alkyl group, an alkenyl group, an alkynyl group, an aryl group or the like can be exemplified. These Rs may also be substituted by the aforementioned substituents. Specific examples of the organic sulfur group include a methylthio group, an ethylthio group, a propylthio group, a butylthio group, a pentylthio group, a hexylthio group, a heptylthio group, and an octylthio group.

As the organic mercapto group of the above substituent, a structure represented by -Si-(R) ₃ can be exhibited. The R may be the same or different, and examples thereof include an alkyl group, an alkenyl group, an alkynyl group, an aryl group and the like. These Rs may also be substituted by the aforementioned substituents. Specific examples of the organic fluorenyl group include a trimethyl fluorenyl group, a triethyl fluorenyl group, a tripropyl decyl group, a tributyl fluorenyl group, a tripentyl fluorenyl group, a trihexyl fluorenyl group, and a pentyl group. Methyl fluorenyl, hexyl dimethyl fluorenyl and the like.

As the thiol group of the above substituent, a structure represented by -C(O)-R can be exhibited. As such R, an alkyl group, an alkenyl group, an aryl group or the like as described above can be exemplified. These Rs may also be substituted by the aforementioned substituents. Specific examples of the mercapto group include a methyl group, an ethenyl group, a propyl group, a butyl group, an isobutyl group, a pentamidine group, an isovaleryl group, and a benzindenyl group.

As the ester group of the above substituent, a structure represented by -C(O)O-R or -OC(O)-R can be exhibited. As such R, an alkyl group, an alkenyl group, an alkynyl group, an aryl group or the like can be exemplified. These Rs may also be substituted by the aforementioned substituents.

As the thioester group of the above substituent, a structure represented by -C(S)O-R or -OC(S)-R can be exhibited. As such R, an alkyl group, an alkenyl group, an alkynyl group, an aryl group or the like can be exemplified. These Rs may also be substituted by the aforementioned substituents.

As the phosphate group of the above substituent, a structure represented by -OP(O)-(OR) ₂ can be exhibited. The R may be the same or different, and examples thereof include an alkyl group, an alkenyl group, an alkynyl group, an aryl group and the like. These Rs may also be substituted by the aforementioned substituents.

As the amidino group of the above substituent, for example, -C(O)NH ₂ , or -C(O)NHR, -NHC(O)R, -C(O)N(R) ₂ , -NRC ( O) The structure represented by R. The R may be the same or different, and examples thereof include an alkyl group, an alkenyl group, an alkynyl group, an aryl group and the like. These Rs may also be substituted by the aforementioned substituents.

The aryl group as the above substituent may be the same as the above aryl group. The aryl group may also be substituted with other substituents as described above.

The alkyl group as the above substituent may be the same as the above alkyl group. The alkyl group may also be substituted with other substituents as described above.

The alkenyl group as the above substituent may be the same as the above alkenyl group. The alkenyl group may also be substituted with other substituents as described above.

The alkynyl group as the above substituent may be the same as the alkynyl group described above. The alkynyl group may also be substituted with other substituents as described above.

In general, when a high-volume structure is introduced, since the reactivity of the amine group or the liquid crystal alignment property may be lowered, R ¹ and R ² may have a hydrogen atom or a carbon number which may have a substituent. The alkyl group of ~5 is preferred, and a hydrogen atom, a methyl group or an ethyl group is particularly preferred.

In the above formula (AM), examples of the specific structure of Y ₁ are shown as Y-1 to Y-106 shown below, but are not limited thereto.

<tetracarboxylic acid derivative>

The polycarboxylic acid imide which can be contained in the liquid crystal alignment agent of the present embodiment and the polycarboxylic acid derivative of the polyimine are not particularly limited, and are used in the reaction with the above-mentioned diamine compound.

Examples of the tetracarboxylic acid derivative include tetracarboxylic dianhydride (indicated by the following formula (CB1)) and tetracarboxylic acid monoanhydride (represented by the following formula (CB2)). , a tetracarboxylic acid (presented by the following formula (CB3)), a dialkyl dicarboxylate (presented by the following formula (CB4)), a dialkyl dicarboxylate (the following formula ( CB5) is indicated by). The tetracarboxylic acid derivative may be used alone or in combination of two or more.

In the above formulae (CB4) and (CB5), R ³ represents a carbon number of 1 to 5, preferably an alkyl group having 1 to 2 carbon atoms.

In the above formulae (CB1) to (CB5), specific examples of Z ₁ include the following formula (Z-1) to formula (Z-46).

The tetracarboxylic acid derivative of the above structure is used in the reaction with the above diamine compound, and is synthesized in a liquid crystal alignment agent by synthesizing a polyimine precursor or a polyimine which is to be constructed. The liquid crystal alignment film of the present embodiment is preferably a tetracarboxylic acid derivative of the above formula (CB1) to (CB5) wherein Z ₁ is a formula (Z-1). This tetracarboxylic acid is reacted with a diamine compound of a specific structure of the above formula (1) to provide a polyimine precursor of a desired structure, and to provide a polyimine of the desired structure. Further, it is possible to provide a liquid crystal alignment film of the present embodiment which can effectively reduce performance degradation at a high level even when exposed to light such as visible light or ultraviolet light. Therefore, the polyimine imide precursor or the polycarboxylic acid imide tetracarboxylic acid derivative which can be contained in the liquid crystal alignment agent of the present embodiment is synthesized, and when one type is used alone, the above formula (CB1) to (CB5) are used. It is preferred that Z ₁ is a tetracarboxylic acid derivative of the formula (Z-1).

<Polyimide precursor>

The polyimine precursor which can be contained in the liquid crystal alignment agent of the present embodiment is a compound obtained by using a diamine component containing the diamine compound of the above formula (1) as an essential component. The polyimine precursors contained in the liquid crystal alignment agent of the present embodiment are, for example, polyamic acid and polyglycolate, and have a structural unit represented by the following formula (PA).

In the above formula (PA), Z is a tetracarboxylic dianhydride (expressed by the above formula (CB1)) derived from the above tetracarboxylic acid derivative, and tetracarboxylic acid monoanhydride (represented by the above formula (CB2)) , tetracarboxylic acid (expressed by the above formula (CB3)), dialkyl dicarboxylate (expressed by the above formula (CB4)), and dichlorodicarboxylate (the above formula (CB5) The base of the Z ₁ group in the indicated).

Further, R _a is a hydrogen atom or a monovalent organic group derived from the above tetracarboxylic acid derivative or an esterifying agent to be described later, and preferably has 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 2 carbon atoms.

In the above formula (PA), Y is a group corresponding to the group of the diamine compound represented by the above formula (1) and a group derived from the Y ₁ group of the other diamine compound represented by the above formula (AM). A ₁ and A ₂ represent a hydrogen atom or a monovalent organic group derived from the R ¹ group and the R ² group of the other diamine compound represented by the above formula (AM).

The polyamine acid of the polyimine precursor is, for example, a diamine component (hereinafter, simply referred to as a diamine component) containing the diamine compound of the above formula (1) as an essential component, and the above four The carboxylic acid derivative is obtained by reacting a tetracarboxylic dianhydride.

As a reaction by the above diamine component and tetracarboxylic dianhydride A well-known method can be used for the method of obtaining the polyamic acid contained in the liquid crystal alignment agent of this embodiment. The synthesis method is a method of reacting a diamine component with a tetracarboxylic dianhydride in an organic solvent. The reaction of the diamine component with the tetracarboxylic dianhydride is relatively easy to carry out in an organic solvent, and is advantageous in that no by-products are produced.

The organic solvent used in the reaction between the diamine component and the tetracarboxylic dianhydride is not particularly limited as long as it is a polylysine which can be dissolved. Specific examples thereof include the following.

For example, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N- Methyl caprolactam, dimethyl hydrazine, tetramethyl urea, pyridine, dimethyl hydrazine, hexamethylene hydrazine, γ-butyrolactone, isopropanol, methoxymethylpentanol, dipentene, Ethyl amyl ketone, methyl decyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve B Acid ester, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl Ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol Dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol Monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, three Propylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, pentyl acetate, butyl butyrate, butyl ether, Diisobutyl Ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethyl carbonate, carbonic acid Propyl propyl ester, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, 3-methoxypropionic acid Methyl ester, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate , 3-methoxypropionic acid butyl ester, diglyme, 4-hydroxy-4-methyl-2-pentanone, 3-methoxy-N,N-dimethylpropanamide, 3- Ethoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropionamide, and the like.

These exemplified solvents may be used singly or in combination. Further, even if the solvent of the poly-proline is not dissolved, it may be used in the above solvent in the range in which the produced polyamine is not precipitated.

Further, since the water in the organic solvent is a factor which hinders the polymerization reaction and hydrolyzes the produced polylysine, it is preferred that the organic solvent be desiccated as much as possible.

When the diamine component and the tetracarboxylic dianhydride are reacted in an organic solvent, a solution in which the diamine component is dissolved or dispersed in an organic solvent is stirred, and the tetracarboxylic dianhydride is directly added or dispersed. Or a method of adding a solution after dissolving in an organic solvent, a method of adding a diamine component to a solution in which a tetracarboxylic dianhydride is dispersed or dissolved in an organic solvent, a method of mutually adding a tetracarboxylic dianhydride and a diamine component, or the like, You can also use any of these methods. Further, when the diamine component or the tetracarboxylic dianhydride is composed of a plurality of compounds, the reaction may be carried out in a state of being mixed in advance, or the reaction may be carried out in sequence, or the respective reactions may be made low. Molecular weight body mixed reaction Made into a high molecular weight body.

The polymerization temperature at this time may be selected from any of -20 ° C to 150 ° C, preferably in the range of -5 ° C to 100 ° C. Further, the reaction can be carried out at any concentration. When the concentration is too low, it becomes difficult to obtain a polymer having a high molecular weight. When the concentration is too high, the viscosity of the reaction liquid becomes too high and it becomes difficult to uniformly stir. The total concentration in the reaction solution of the diamine component and the tetracarboxylic dianhydride is preferably from 1% by mass to 50% by mass, more preferably from 5% by mass to 30% by mass. The initial stage of the reaction may be carried out at a high concentration, and then an organic solvent may be added.

In the polymerization reaction of polyamic acid, the ratio of the total number of moles of the tetracarboxylic dianhydride to the total number of moles of the diamine component is preferably 0.8 to 1.2. As in the usual polycondensation reaction, the molecular weight of the poly-proline which is formed when the molar ratio approaches 1.0 is larger.

<Polyurethane>

The polyimine precursor which can be contained in the liquid crystal alignment agent of the present embodiment is polyamic acid, polyglycolate or the like as described above. For the polyamidite ester of the polyimine precursor, for example, a diamine component and a tetracarboxylic acid derivative containing the above-described diamine compound of the above formula (1) as an essential component can be used, and as shown below (1) ) ~ (3) method for synthesis.

(1) Method for synthesizing from polyamic acid

The polyamine ester can be synthesized by esterifying a polyamic acid obtained from a diamine component and a tetracarboxylic dianhydride.

Specifically, the reaction can be carried out for 30 minutes to 24 hours by using polyglycine and an esterifying agent in the presence of an organic solvent at -20 ° C to 150 ° C, preferably at 0 ° C to 50 ° C. The reaction is synthesized from 1 hour to 4 hours.

The above esterifying agent is preferably one which can be easily removed by purification, and examples thereof include N,N-dimethylformamide dimethyl acetal and N,N-dimethylformamide diethyl ester. Acetal, N,N-dimethylformamide dipropyl acetal, N,N-dimethylformamide dinepentyl butyl acetal, N,N-dimethylformamide II T-butyl acetal, 1-methyl-3-p-tolyltriazene, 1-ethyl-3-p-tolyltriazene, 1-propyl-3-p-tolyltriazole Alkene, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride or the like. The amount of the esterifying agent added is preferably 1 mol with respect to the repeating unit of polyamic acid, and is preferably 2 mol equivalents to 6 mol equivalents.

The solvent used in the above reaction is preferably N,N-dimethylformamide, N-methyl-2-pyrrolidone or γ-butyrolactone from the viewpoint of solubility of the polymer. One type may be used or two or more types may be used in combination. The concentration at the time of the synthesis is preferably from 1% by mass to 30% by mass, and preferably from 5% by mass to 20% by mass, from the viewpoint that the precipitation of the polymer is less likely to occur and the high molecular weight body is easily obtained.

(2) A method for synthesizing by reacting a dicarboxylic acid dicarboxylate with a diamine component

The polyphthalamide type can be synthesized from a dicarboxylic acid dicarboxylic acid diester and the above diamine component.

Specifically, by dicarboxylic acid dicarboxylate and two The amine component is synthesized in the presence of a base and an organic solvent at -20 ° C to 150 ° C, preferably at 0 ° C to 50 ° C for 30 minutes to 24 hours, preferably for 1 to 4 hours.

As the base, for example, pyridine, triethylamine, 4-dimethylaminopyridine or the like can be used, but pyridine is preferred in order to allow the reaction to proceed gently. The amount of the base to be added is preferably from 2 mol to 4 mol per mol of the dicarboxylic acid dicarboxylic acid diester from the viewpoint of easily removable amount and easy availability of a high molecular weight body.

The solvent used in the above reaction is preferably N-methyl-2-pyrrolidone or γ-butyrolactone, and may be used alone or in combination. More than one kind. The concentration of the polymer at the time of synthesis is preferably from 1% by mass to 30% by mass, and preferably from 5% by mass to 20% by mass, from the viewpoint that precipitation of the polymer is less likely to occur and that a high molecular weight body is easily obtained. Further, in order to prevent hydrolysis of the dicarboxylic acid dicarboxylic acid diester, it is preferred that the solvent used in the synthesis of the polyglycolate is dehydrated as much as possible, and it is preferable to prevent the incorporation of outside air in a nitrogen atmosphere.

(3) Method for synthesizing tetracarboxylic acid diester and diamine component

The polyglycolate can be synthesized by polycondensation of a tetracarboxylic acid diester and the above diamine component.

Specifically, the tetracarboxylic acid diester and the diamine component can be reacted for 30 minutes at 0 ° C to 150 ° C, preferably 0 ° C to 100 ° C in the presence of a condensing agent, a base or an organic solvent. ~24 hours, preferably reacted for 3 hours to 15 hours to synthesize.

As the aforementioned condensing agent, for example, triphenyl phosphate or cyclohexyl group can be used. Carboimine, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide ruthenate, N,N'-carbonyldiimidazole, dimethoxy-1,3, 5-triazinylmethylmorpholinium, O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate, O-(benzo Triazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate, (2,3-dihydro-2-thioketo-3-benzoxazolyl) Diphenyl phosphonate and the like. The amount of the condensing agent added is preferably 2 moles to 3 moles per mole of the tetracarboxylic acid diester.

As the base, a tertiary amine such as pyridine or triethylamine can be used. The amount of the base to be added is preferably from 2 moles to 4 moles per mole of the diamine component from the viewpoint of being easily removable and easily obtaining a high molecular weight body.

Further, in the above reaction, the reaction can be efficiently carried out by adding a Lewis acid as an additive. The Lewis acid is preferably a lithium halide such as lithium chloride or lithium bromide. The amount of Lewis acid added is preferably from 0 moles to 1.0 moles relative to the diamine component.

Among the above three methods for synthesizing polyglycolate, since a high molecular weight polyglycolate can be obtained, the synthesis method of the above (1) or (2) is particularly preferable.

The solution of the polyglycolate obtained according to the above method can be precipitated by injecting into a poor solvent while uniformly stirring. After several times of precipitation and washing with a poor solvent, the powder of the purified polyphthalate is obtained at room temperature or by heating. The poor solvent is not particularly limited, and examples thereof include water, methanol, ethanol, hexane, butyl cellosolve, acetone, toluene, and the like.

<polyimine]

The liquid crystal alignment agent of the present embodiment contains at least one polymer selected from the group consisting of the above polyimine precursor and polyimine. The polyimine contained in the liquid crystal alignment agent of the present embodiment is a polyimine obtained by dehydrating and blocking a polyamic acid of the polyimine precursor. In other words, the polyamidimide is obtained by dehydration ring-closure of the polyaminic acid precursor of the above-mentioned polyamidiamine precursor synthesized using a diamine component containing the specific structural diamine compound of the above formula (1) as an essential component. Polyimine. This polyimine is included in the liquid crystal alignment agent of this embodiment, and can be useful as a polymer for obtaining a liquid crystal alignment film.

Further, in the polyimine contained in the liquid crystal alignment agent of the present embodiment, the dehydration ring closure ratio (the imidization ratio) of the proline group is not necessarily required to be 100%, and may be arbitrarily adjusted depending on the intended use or purpose.

<Method for producing polyimine]

When the polyimine is obtained by using the above polyamic acid, a method of ruthenium imidating polylysine may be carried out by directly heating a polyaminic acid solution to thermally imidize and polylysine. The catalyst is added to the solution and the catalyst is imidized.

In this case, the above polylysine is preferably imidized by a catalyst which can be reacted at a relatively low temperature.

The catalyst oxime imidization of polylysine may be carried out by adding a basic catalyst and an acid anhydride to the polyaminic acid solution, and stirring at -20 ° C to 250 ° C, preferably 0 ° C to 180 ° C. The amount of the alkaline catalyst is 0.5 moles to 30 moles of the proline group, preferably 2 moles to 20 moles, and the amount of the anhydride is 1 mole of the prolyl group. Moer times, preferably 3 mo Ears are ~30 moles.

Examples of the basic catalyst used for the imidization of the catalyst oxime include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, etc., among which pyridine is also available. It is preferred that the reaction be moderately alkaline.

Examples of the acid anhydride used for the imidization of the catalyst oxime include anhydrous acetic acid, anhydrous trimellitic acid, anhydrous pyrogal acid and the like. Among them, it is preferred to use anhydrous acetic acid to facilitate the purification after completion of the reaction.

The imidization rate of the imidization of the catalyst can be controlled by adjusting the amount of the catalyst, the reaction temperature, and the reaction time.

The components which can be contained in the liquid crystal alignment agent of the present embodiment have been described above, and the liquid crystal alignment agents of the present embodiment prepared by using them are described next.

<Liquid alignment agent>

In the liquid crystal alignment agent of the present embodiment, a coating liquid for a liquid crystal alignment film is formed, and a resin component for forming a resin film is dissolved in an organic solvent. Here, the resin component is a resin component containing at least one polymer selected from the group consisting of a polyimide intermediate and a polyimine. In this case, the content of the resin component is preferably 1% by mass to 20% by mass, more preferably 3% by mass to 15% by mass, even more preferably 3% by mass to 10% by mass.

Further, in the present embodiment, the resin component may be all of the above polymers, or may be a mixture of other polymers. at this time, The content of the polymer other than the above polymer in the resin component is 0.5% by mass to 15% by mass, preferably 1% by mass to 10% by mass.

The organic solvent to be used in the liquid crystal alignment agent of the present embodiment is not particularly limited as long as it is an organic solvent capable of dissolving the resin component such as the above polymer. Specific examples thereof include the following.

For example, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidine Ketone, N-ethylpyrrolidone, N-vinylpyrrolidone, dimethyl hydrazine, tetramethylurea, pyridine, dimethyl hydrazine, hexamethylene hydrazine, γ-butyrolactone, 3-methoxy -N,N-dimethylpropanamide, 3-ethoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, 1,3- Dimethyl-tetrahydroimidazolidone, ethyl amyl ketone, methyl decyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, ethyl carbonate Propyl carbonate, diglyme, 4-hydroxy-4-methyl-2-pentanone, and the like. These may be used alone or in combination.

The liquid crystal alignment agent of this embodiment may contain components other than the above. Examples thereof include a solvent or a compound which improves film thickness uniformity or surface smoothness when a liquid crystal alignment agent is applied, a compound which improves adhesion between a liquid crystal alignment film and a substrate, and the like.

Specific examples of the solvent (lean solvent) for improving film thickness uniformity or surface smoothness include the following.

For example, isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate may be mentioned. , butyl carbitol, ethyl carbitol, ethyl carbitol Acid ester, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol-tert- Butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl Ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl Acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, pentyl acetate, butyl butyrate , butyl ether, diisobutyl ketone, methyl cyclohexene, propyl ether, dihexyl ether, 1-hexanol, n-hexane, n-pentane, n-octane, diethyl ether, Methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, 3 -ethyl ethoxypropionate, 3-methyl Ethyl propyl propionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, 1-methoxy-2- Propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol- 1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, methyl lactate, A solvent having a low surface tension such as ethyl lactate, n-propyl lactate, n-butyl lactate or isoamyl lactate.

These poor solvents can be used in one type or in a plurality of types. When the solvent is used in the above manner, it is preferably 5% by mass to 80% by mass, more preferably 20% by mass to 60% by mass based on the total amount of the solvent contained in the liquid crystal alignment agent. quality%.

Examples of the compound for improving film thickness uniformity or surface smoothness include a fluorine-based surfactant, a polyoxyn-based surfactant, and a nonionic surfactant.

More specifically, for example, Eftop (registered trademark) EF301, EF303, EF352 (manufactured by Tohkem Products Co., Ltd.), Megafac (registered trademark) F171, F173, R-30 (manufactured by Dainippon Ink Co., Ltd.), Fluorad FC430, FC431 (for example) Sumitomo 3M Company, Asahiguide (registered trademark) AG710, Surflon (registered trademark) S-382, SC101, SC102, SC103, SC104, SC105, SC106 (made by Asahi Glass Co., Ltd.).

The use ratio of the surfactants is preferably 0.01 parts by mass to 2 parts by mass, more preferably 0.01 parts by mass to 1 part by mass, per 100 parts by mass of the resin component contained in the liquid crystal alignment agent.

Specific examples of the compound which improves the adhesion between the liquid crystal alignment film and the substrate include a functional decane-containing compound or an epoxy group-containing compound described below.

For example, 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane, 2-aminopropyltriethoxydecane , N-(2-Aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxydecane, 3- Ureapropyl propyl trimethoxy decane, 3-ureidopropyl triethoxy decane, N-ethoxycarbonyl-3-aminopropyl trimethoxy decane, N-ethoxycarbonyl-3-amino group Propyltriethoxydecane, N-triethoxydecylpropyltriethylamine, N-trimethoxydecylpropyltriethylamine, 10-trimethoxydecyl-1 , 4,7- Triazadecane, 10-triethoxyindolyl-1,4,7-triazadecane, 9-trimethoxyindolyl-3,6-diazaindolyl acetate, 9- Triethoxyindolyl-3,6-diazaindolyl acetate, N-benzyl-3-aminopropyltrimethoxydecane, N-benzyl-3-aminopropyltriethoxy Baseline, N-phenyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyltriethoxydecane, N-bis(oxyethylene)-3-aminopropyl Trimethoxydecane, N-bis(oxyethylene)-3-aminopropyltriethoxydecane, ethylene glycol diepoxypropyl ether, polyethylene glycol diepoxypropyl ether, propylene glycol diepoxide Propyl ether, tripropylene glycol diepoxypropyl ether, polypropylene glycol diepoxypropyl ether, neopentyl glycol diepoxypropyl ether, 1,6-hexanediol diepoxypropyl ether, glycerol Diepoxypropyl ether, 2,2-dibromo neopentyl glycol diepoxypropyl ether, 1,3,5,6-tetraepoxypropyl-2,4-hexanediol, N,N, N',N',-tetraepoxypropyl-m-nonanediamine, 1,3-bis(N,N-diepoxypropylaminomethyl)cyclohexane, N,N,N', N',-tetraepoxypropyl-4,4'-diaminodiphenylmethane, and the like.

When the compound is used to improve the adhesion to the substrate, the amount thereof is preferably 0.1 parts by mass to 30 parts by mass, more preferably 1 part by mass, per 100 parts by mass of the resin component contained in the liquid crystal alignment agent. 20 parts by mass. When the amount of use is less than 0.1 part by mass, the effect of improving the adhesion cannot be expected, and when it is more than 30 parts by mass, the liquid crystal alignment property of the liquid crystal alignment film formed may be lowered.

In the liquid crystal alignment agent of the present embodiment, in addition to the above, the dielectric properties of the liquid crystal alignment film and the electrical properties such as conductivity can be improved for the purpose of not impairing the effects of the present invention. Or a conductive material, and also added to increase the hardness of the film when the liquid crystal alignment film is formed or A crosslinkable compound for the purpose of density.

Next, a liquid crystal alignment film according to an embodiment of the present invention and a liquid crystal display element using the same will be described.

<Formation of liquid crystal alignment film>

The liquid crystal alignment agent of the present embodiment contains at least one polymer selected from the group consisting of a polyimine precursor synthesized using a diamine component containing the diamine compound of the above formula (1) as an essential component, and a polyimine. Further, the liquid crystal alignment agent of the present embodiment is preferably applied to a substrate by being filtered before being applied to a substrate, dried by prebaking, and then calcined by heating to form a polymer film containing polyimine. .

The coating method to be applied to the substrate by using the liquid crystal alignment agent of the present embodiment is not particularly limited, and industrially, it is generally a method of screen printing, lithography, offset printing, or inkjet method. As another coating method, there are a dipping method, a roll coating method, a slit coating method, a spin coating method, a spray coating method, and the like, and these may be used depending on the purpose. In the liquid crystal alignment agent of the present embodiment, even when the above coating method is used, the coatability is also good.

The drying step of pre-baking after coating the liquid crystal alignment agent is not an essential step, but is included when the time from the application to the heating and firing is performed by the respective substrates instead of being fixed or after the coating is not immediately heated and baked. The drying step is preferred. The drying by the prebaking is such that the solvent can be evaporated to the extent that the shape of the coating film is not deformed when the substrate is conveyed or the like.

The means for drying is not particularly limited. If a specific example is given, it is dried on a hot plate at 50 ° C to 120 ° C, preferably 80 ° C to 120 ° C. A minute to 30 minutes, preferably 1 minute to 5 minutes is preferred.

The firing of the substrate coated with the liquid crystal alignment agent can be carried out at a temperature of from 120 ° C to 350 ° C by a heating means such as a hot plate, a heat cycle type oven or an IR (infrared) type oven. The firing temperature is preferably from 140 ° C to 300 ° C, more preferably from 180 ° C to 250 ° C. When the liquid crystal alignment agent contains polyamic acid or polyphthalate, the conversion ratio of the polyimide may change depending on the firing temperature, but the liquid crystal alignment agent of the present embodiment must be 100%. Imine. Further, the firing time of the liquid crystal alignment agent coating film can be set to any time. When the baking time is too short, display failure may occur due to the influence of the residual solvent, and therefore it is preferably from 5 minutes to 60 minutes, more preferably from 10 minutes to 40 minutes.

The thickness of the polymer film containing polyimine obtained after firing is not conducive to the power consumption of the liquid crystal display element when it is too thick, and the reliability of the liquid crystal display element is lowered when it is too thin, so Preferably, it is 10 nm to 200 nm, more preferably 50 nm to 100 nm. When the liquid crystal is aligned horizontally or obliquely, it is preferred to use an alignment treatment in which the surface of the film of the polymer film after firing is applied to perform rubbing in a fixed direction.

The liquid crystal alignment film which is effective in reducing performance deterioration even if it is subjected to ultraviolet irradiation by the liquid crystal alignment film of the present embodiment which is formed by operation, can be provided by the step of irradiating ultraviolet rays through the formation region of the pixel, but the performance is obtained. The liquid crystal display element of this embodiment is suppressed in which the deterioration is deteriorated.

Embodiment 2

In the liquid crystal display device of the second embodiment of the present invention, in the same manner as the liquid crystal display device of the first embodiment, the liquid crystal alignment film which is effective in reducing the performance even if it is irradiated with ultraviolet rays is used. Further, in the case of the liquid crystal display device of the second embodiment, the liquid crystal alignment film is subjected to photo-alignment treatment by ultraviolet irradiation, and further exhibits a liquid crystal alignment control ability. Therefore, the liquid crystal display element of the second embodiment of the present invention is a liquid crystal display element which is formed by irradiating ultraviolet rays to a region where a pixel is formed on a liquid crystal alignment film, and is reduced in performance deterioration. .

In the liquid crystal display device of the present embodiment, as in the first embodiment, a color liquid crystal display device of a TN (Twisted Nematic) mode can be used. Therefore, the same structure as the liquid crystal display element 1 of Fig. 1 of the first embodiment described above can be obtained, and the description thereof will not be repeated.

In the same manner as the liquid crystal alignment film of the liquid crystal display element of the first embodiment, the liquid crystal alignment film of the liquid crystal display device of the second embodiment is preferably formed by using a liquid crystal alignment agent. Further, in the liquid crystal display element of the present embodiment, the liquid crystal alignment film of the present embodiment is formed by the step of irradiating ultraviolet rays through the formation region of the pixel, but the reduction in performance deterioration is suppressed. The liquid crystal alignment agent of the embodiment is preferably formed.

Further, the liquid crystal alignment agent used in the present embodiment is the liquid crystal alignment agent of the first embodiment, and the obtained liquid crystal alignment film can achieve excellent liquid crystal alignment control ability by photo-alignment treatment, and is selected from the group consisting of polyimide precursor tetracarboxylic acid derivative of a diamine component containing a diamine of the formula (1) of the compound of the above formula (CB1) ~ (CB5) Z 1 of the formula (Z-1) of the form Preferably, the composition and at least one polymer of the polyimine obtained by imidating the oxime are preferably formed. As a result, the liquid crystal alignment film of the present embodiment contains the diamine component selected from the group consisting of the diamine compound containing the above formula (1) and Z ₁ in the above formula (CB1) to (CB5) as the formula (Z-1). The polyimine precursor formed by the tetracarboxylic acid derivative and at least one polymer of the polyimine obtained by imidating the quinone.

The formation of the liquid crystal alignment film of the present embodiment can be the same as that of the first embodiment. Further, the photo-alignment treatment method of the liquid crystal alignment film of the present embodiment is not particularly limited, and it is preferable to obtain uniform liquid crystal alignment by using polarized ultraviolet rays. In this case, the method of irradiating the polarized ultraviolet rays is not particularly limited. For example, a substrate on which a polymer film containing a polymer such as polyimine is formed may be irradiated with polarized ultraviolet rays through a polarizing plate in a fixed direction. Further, the incident angle of the polarized ultraviolet light may be changed to be irradiated twice or more. Further, as long as substantial polarization can be obtained, the unpolarized ultraviolet rays may be obliquely irradiated at a predetermined angle from the normal line of the substrate.

As the ultraviolet wavelength to be used, ultraviolet rays in the range of 100 nm to 400 nm can be generally used, and it is particularly preferable to select an optimum wavelength via a filter or the like depending on the type of the polymer film to be used. Further, the irradiation time of the ultraviolet rays is generally in the range of several seconds to several hours. Further, in consideration of industrial productivity, it is preferable to select a necessary amount to achieve good liquid crystal alignment control ability depending on the type of liquid crystal alignment film to be used.

The liquid crystal display element of the second embodiment can be borrowed from Manufactured under the operation. In addition, the liquid crystal display element of this embodiment can be made into the same structure as the liquid crystal display element 1 of FIG. 1 of the first embodiment, and the description of the common constituent elements will be described with reference to FIG. 1 .

First, the TFT substrate 2 of the above configuration is prepared. The TFT substrate 2 is manufactured by, for example, forming a TFT or various electrodes including the pixel electrode 6 on a substrate 5 made of a transparent glass substrate or the like according to a known method. Further, the liquid crystal alignment film 12 of the present embodiment to which the photoalignment treatment is applied is disposed on the TFT substrate 2.

Further, the CF substrate 3 of the above configuration was prepared. The CF substrate 3 is formed by, for example, patterning a CF layer 7 having a colored layer 9 and a black matrix 10, a common electrode 11 and the like on a substrate 15 made of a transparent glass substrate or the like. Thereafter, the liquid crystal alignment film 12 to which the photoalignment treatment is applied is disposed on the surface of the common electrode 11. Further, the black matrix is made of a metal material such as Ta (钽), Cr (chromium), Mo (molybdenum), Ni (nickel), Ti (titanium), Cu (copper), or Al (aluminum), and is dispersed with carbon. The resin material of the black pigment or the coloring layer of the plurality of colors each having light transmittance is formed by laminating a resin material or the like.

Next, a sealing material is used around the formation region of the pixel on which the pixel electrode 6 is formed in the TFT substrate 2, or a method of printing into a desired shape or coating by a spin coating method according to a method of a dispenser or a method of printing into a desired shape. Thereafter, the sealing material 16 is formed in a frame shape by a method of patterning by a photolithography method or the like. As the sealing material, for example, a thermosetting type can be used.

Next, the TFT substrate 2 and the CF substrate 3 are held together. The spacer is preferably 1 μm to 30 μm, more preferably 2 μm to 10 μm, and the optical axis projection direction of the polarized ultraviolet light irradiated on each of the substrates is, for example, arranged orthogonally and fixed around the sealing material 16 . Next, liquid crystal is injected between the TFT substrate 2 and the CF substrate 3 and sealed to form the liquid crystal layer 4. The method of liquid crystal sealing is not particularly limited, and a vacuum method in which a formation region of a pixel surrounded by the sealing material 16 between the TFT substrate 2 and the CF substrate 3 is decompressed and then injected into a liquid crystal can be used. Further, a dropping method or the like in which the liquid crystal is dropped after the liquid crystal is applied as described in the first embodiment can be exemplified.

Thereafter, a polarizing plate 17 is provided on the outer surface side opposite to the opposite side of the liquid crystal layer 4 of the TFT substrate 2 and the CF substrate 3 to form the liquid crystal display element 1.

Therefore, in the production of the liquid crystal display device of the present embodiment, the step of irradiating the ultraviolet light is a step of performing the alignment treatment of the liquid crystal alignment film, and the liquid crystal alignment film is provided with the control ability of the liquid crystal alignment. The irradiation light system has a wavelength characteristic suitable for the light alignment treatment of the liquid crystal alignment film, and as described above, the wavelength can be set to ultraviolet rays of 100 nm to 400 nm. Further, the amount of ultraviolet rays to be irradiated is preferably selected from the range of the optical alignment treatment in accordance with the type of the liquid crystal alignment film as described above.

The liquid crystal display element of the present embodiment is configured by using a liquid crystal alignment film comprising at least one polymer selected from the group consisting of a polyimine precursor of the above structure and a polyimine obtained by imidating the oxime. It is a light alignment treatment, and deterioration of performance can be suppressed even if it is irradiated with ultraviolet rays in the formation region of the pixel. Therefore, the liquid crystal display element of the present embodiment is irradiated with ultraviolet light even through the formation region of the pixel due to the photo-alignment treatment. In the case of the step of the line, it is possible to suppress the deterioration of the performance caused by the ultraviolet irradiation which has been conventionally regarded as a problem. In other words, according to the present embodiment, in particular, it is possible to provide a liquid crystal display element in which reduction in display quality produced by irradiation with light irradiated with ultraviolet light is suppressed.

Further, in the liquid crystal display element 1 of the present embodiment, a photocurable sealing material such as a visible light curing type or an ultraviolet curing type can be used when the sealing material 16 is formed. As the visible light curing type sealing material, for example, a photocurable resin which is cured by irradiation of visible light light energy such as an acrylic resin, a methacrylic resin, an epoxy resin or a polyoxynoxy resin can be used. Further, as the ultraviolet curable sealing material, the same as those described in the first embodiment can be used.

Even if the sealing material is a photocurable type, the liquid crystal display element of the present embodiment is formed by using a liquid crystal alignment film containing the polyimine film of the above-described structure. For example, even if the sealing material 16 is cured, even in the pixel formation region. The deterioration of performance can be suppressed by exposure to visible light or ultraviolet rays. Therefore, in the case where the liquid crystal display element of the present embodiment is formed by irradiating visible light or ultraviolet rays through the formation region of the pixel after the photo-alignment treatment, performance deterioration due to visible light irradiation can be suppressed.

Further, the liquid crystal display device of the present embodiment may be in the STN (Super Twisted Nematic) mode, the IPS (In-Planes Switching) mode, the VA (Vertical Alignment) mode, or the OCB (Optically Compensated Birefringence) in addition to the TN mode described above. ) LCD mode such as mode. At this time, the TFT substrate or the CF substrate is different from the example shown in FIG. 1, and a known structure suitable for each liquid crystal mode can be obtained.

Embodiment 3

A liquid crystal display element according to a third embodiment of the present invention is a PSA (Polymer Sustained Alignment) type liquid crystal display element. The liquid crystal display element of the PSA type is constituted by using a liquid crystal alignment film of a vertical alignment type as a liquid crystal alignment film.

Therefore, in the same manner as the liquid crystal alignment film of the liquid crystal display element of the first embodiment, the liquid crystal alignment film of the liquid crystal display device of the third embodiment is preferably formed by using a liquid crystal alignment agent. Further, in the liquid crystal alignment element of the present embodiment, the liquid crystal display element of the present embodiment which is formed by the step of irradiating ultraviolet rays in the formation region of the pixel and which is suppressed from being deteriorated in performance is used, and the first embodiment is used. It is preferably formed by a liquid crystal alignment agent. Further, in particular, in the obtained liquid crystal alignment film, in order to realize vertical alignment of the liquid crystal, a polyfluorene precursor containing a structure selected from a structure suitable for vertical alignment and a polyfluorene obtained by imidating the ruthenium are used. The liquid crystal alignment agent of the first embodiment of at least one polymer of the imine is preferably formed.

In the method for producing a liquid crystal display device of the third embodiment, as described above, a liquid crystal alignment agent of the first embodiment containing a polymer such as a polyimide precursor having a structure suitable for vertical alignment can be used to form a liquid crystal on the substrate. After the alignment film is formed, it is obtained by forming a liquid crystal cell according to a known method. As an example of the production of the liquid crystal cell, a method in which a pair of substrate holding spacers on which the liquid crystal alignment film is formed is fixed by a sealing material, and a liquid crystal is injected and sealed is generally used. At this time, the size of the spacer used is 1 μm to 30 μm, preferably It is 2 μm to 10 μm.

The substrate used for the PSA liquid crystal display device of the present embodiment is not particularly limited as long as it is a substrate having high transparency, and a substrate on which a transparent electrode for driving a liquid crystal is formed is preferably formed on the substrate. The PSA type liquid crystal display element can be used as a substrate or a standard PVA or MVA electrode pattern or a protrusion pattern. However, as an example of a PSA liquid crystal display device, a line width/slit electrode pattern of 1 μm to 10 μm is formed on a single-sided substrate, and a structure in which a slit pattern or a protrusion pattern is not formed on the opposite substrate may be used. As a liquid crystal display element of the PSA type according to the configuration of the liquid crystal display element of the configuration example, the manufacturing process can be simplified, and high transmittance can be obtained.

Further, as the substrate used for the liquid crystal display device of the PSA method of the present embodiment, a TFT substrate in which a TFT or an electrode is disposed may be used. As an example, a PSA liquid crystal display device driven by a TFT can be provided.

When the liquid crystal display device of the PSA system of the present embodiment is of a transparent type, it is preferable to use the above-described transparent substrate, and in the case of a reflective type, if it is only a single-sided substrate, a germanium wafer or the like can be used. An opaque substrate. At this time, a material such as aluminum which can reflect light can be used as the electrode formed on the substrate.

The method of injecting the liquid crystal is not particularly limited, and examples thereof include a vacuum method in which a liquid crystal cell is prepared, a vacuum method in which a liquid crystal is injected, a dropping method in which a liquid crystal is dropped, and the like.

The liquid crystal used in the PSA type liquid crystal display device uses a small amount of liquid crystal to which a photopolymerizable compound (preferably 0.2% by weight to 1% by weight) is added. After the liquid crystal cell in which the liquid crystal is formed and the liquid crystal layer is formed is obtained, a voltage is applied between the electrodes of the substrates on both sides of the liquid crystal layer holding the liquid crystal cell. Further, by irradiating ultraviolet rays in a state where a voltage is applied, the polymerizable compound is polymerized and crosslinked in this state, and as a result, the response speed of the liquid crystal display element is increased. Here, the applied voltage is 5 V _pp ~ 30 V _pp , preferably 5 V _pp ~ 20 V _pp . The irradiation amount of the ultraviolet ray is 1 J to 60 J, preferably 40 J or less, and when the amount of ultraviolet ray irradiation is small, the reliability of the liquid crystal display element can be suppressed from being lowered, and the irradiation time of the ultraviolet ray can be reduced, whereby the stagnation time in manufacturing can be shortened. Therefore, the productivity can be appropriately improved.

As described above, the liquid crystal display element of the PSA system according to the third embodiment of the present invention is similar to the liquid crystal display element of the first embodiment, and is formed by using a liquid crystal alignment film which can effectively suppress performance deterioration even when exposed to ultraviolet rays. . In the case of the liquid crystal display device of the third embodiment, a liquid crystal-based compound is used, and when a liquid crystal display element is produced, the photopolymerizable compound is irradiated with ultraviolet light to realize liquid crystal. Desirable characteristics. Therefore, since the liquid crystal display element of the third embodiment of the present invention reacts the photopolymerizable compound in the liquid crystal, the ultraviolet light is irradiated through the formation region of the pixel, and the deterioration of the performance is suppressed. Liquid crystal display element.

Embodiment 4

The liquid crystal display element of the fourth embodiment of the present invention is irradiated with ultraviolet rays. The liquid crystal display element of the mode. In the liquid crystal display device of the ultraviolet irradiation method, a liquid crystal alignment agent is applied to two substrates to form a liquid crystal alignment film, and the liquid crystal alignment film is disposed so as to face two substrates in a general direction, and liquid crystal is sandwiched between the two substrates. A liquid crystal display element of a vertical alignment (VA) mode which is formed by applying an electric field to a liquid crystal layer while irradiating ultraviolet light. The liquid crystal display element of the ultraviolet irradiation method is configured by using a liquid crystal alignment film of a vertical alignment type as a liquid crystal alignment film.

Therefore, in the same manner as the liquid crystal alignment film of the liquid crystal display element of the first embodiment, the liquid crystal alignment film of the liquid crystal display device of the fourth embodiment is preferably formed by using a liquid crystal alignment agent. Further, in the liquid crystal alignment element of the present embodiment, the liquid crystal display element of the present embodiment which is formed by the step of irradiating ultraviolet rays in the formation region of the pixel and which is suppressed from being deteriorated in performance is used, and the first embodiment is used. It is preferably formed by a liquid crystal alignment agent. Further, in particular, in the obtained liquid crystal alignment film, in order to realize vertical alignment of the liquid crystal, a polyfluorene precursor containing a structure selected from a structure suitable for vertical alignment and a polyfluorene obtained by imidating the ruthenium are used. The liquid crystal alignment agent of the first embodiment of at least one polymer of the imine is preferably formed.

Further, it is not necessary to add a photopolymerizable compound to the liquid crystal as in the above PSA method, and to use a polyimine precursor comprising a structure selected from a suitable ultraviolet irradiation method and a polyfluorene obtained by imidating the oxime. The liquid crystal alignment agent of the first embodiment of at least one polymer of the imine is particularly preferable. Thereby, the response characteristics of the liquid crystal can be simply improved.

The manufacturing method of the liquid crystal display element of the fourth embodiment is As described above, the liquid crystal alignment agent of the first embodiment comprising a polymer such as a polyimine precursor having a structure suitable for a vertical alignment and suitable for an ultraviolet irradiation method can be used, and a liquid crystal alignment film is formed on the substrate, and then a known method can be used. Made of liquid crystal cells. In the case of producing a liquid crystal cell, for example, a substrate on which one of the liquid crystal alignment films is formed is prepared, and a spacer is placed on the liquid crystal alignment layer of the single substrate, and the liquid crystal alignment layer is bonded to the inner side. A substrate, a method of sealing a liquid crystal after pressure-reducing, or a method in which a liquid crystal is dropped onto a surface of a liquid crystal alignment layer in which a spacer is dispersed, and a substrate is bonded and sealed. At this time, the size of the spacer used is 1 μm to 30 μm, preferably 2 μm to 10 μm.

The substrate used for the production of the liquid crystal display device of the present embodiment is not particularly limited as long as it is a substrate having high transparency, and a substrate on which a transparent electrode for driving a liquid crystal is formed is preferably formed on the substrate. The liquid crystal display element of the ultraviolet irradiation method can use a substrate or a standard PVA or MVA electrode pattern or a protrusion pattern. However, as an example of a liquid crystal display element of an ultraviolet irradiation method, a line width/slit electrode pattern of 1 μm to 10 μm is formed on a single-sided substrate, and a structure in which a slit pattern or a protrusion pattern is not formed on a counter substrate is also It is possible to simplify the manufacturing process and obtain a high transmittance by the liquid crystal display element of the ultraviolet irradiation method of the configuration example as the action of the desired liquid crystal.

In the substrate used for the liquid crystal display device of the ultraviolet irradiation method of the present embodiment, a TFT substrate in which a TFT or an electrode is disposed may be used. As an example, a liquid crystal display device which is driven by a TFT by ultraviolet irradiation can be provided.

When the liquid crystal display element of the ultraviolet irradiation method of the present embodiment is of a transmissive type, it is preferable to use the above-described transparent substrate, and in the case of a reflective type, if only a single-sided substrate is used, a silicon wafer can be used. Etc. opaque substrate. At this time, a material such as aluminum which can reflect light can be used as the electrode formed on the substrate.

The liquid crystal used in the liquid crystal display device of the present embodiment may be a liquid crystal to which no photopolymerizable compound is added, or a liquid crystal to which a photopolymerizable compound is added. The liquid crystal display element of the present embodiment can increase the response speed by using any of the liquid crystals.

The step of applying an electric field to the liquid crystal layer and simultaneously irradiating the ultraviolet ray is, for example, a method of applying an electric field to the liquid crystal layer by applying a voltage between the electrodes provided on the substrate, and irradiating the ultraviolet ray while maintaining the electric field. Here, the applied voltage is 55V _pp ~ 30V _pp, preferably 5V _pp ~ 20V _pp. The irradiation amount of the ultraviolet ray is 1 J to 60 J, preferably 40 J or less, and when the amount of ultraviolet ray irradiation is small, the reliability of the liquid crystal display element can be suppressed from being lowered, and the irradiation time of the ultraviolet ray can be reduced, whereby the stagnation time in manufacturing can be shortened. Therefore, the productivity can be appropriately improved.

As described above, in the liquid crystal display device of the ultraviolet irradiation method according to the fourth embodiment of the present invention, similarly to the liquid crystal display device of the first embodiment, a liquid crystal alignment film which can effectively suppress performance deterioration even when irradiated with ultraviolet rays is used. Composition. Further, in the case of the liquid crystal display element of the fourth embodiment, the formation region of the pixel in which the liquid crystal layer is formed is irradiated with ultraviolet rays at the time of production, and the desired response characteristics of the liquid crystal can be achieved. Therefore, in the fourth embodiment of the present invention, the liquid crystal display element is crystal-paired. A liquid crystal display element in which a liquid crystal layer is irradiated with ultraviolet rays in a region where a pixel is formed, and a deterioration in performance is suppressed.

[Examples]

The invention will now be described in more detail by way of examples. Furthermore, the invention is not to be construed as being limited by the terms.

The main compounds and abbreviations and structures used in the examples and comparative examples are as follows.

<structural>

<tetracarboxylic acid derivative>

CBDA: 1,2,3,4-cyclobutane tetracarboxylic dianhydride

<Diamine compound>

DDM: 4,4'-diaminodiphenylmethane

Biphenyl: 4,4'-diamino-p-triphenyl

ADA: bis(p-aminophenyl)-9,10-蒽

p-PDA: 1,4-phenylenediamine

<solvent>

NMP: N-methyl-2-pyrrolidone

BC: butyl cellosolve

Next, the molecular weight measurement method to be carried out in the present examples and comparative examples will be described.

[Molecular weight measurement]

The molecular weight of the polyimine of the synthesis example was carried out by using a room temperature gel permeation chromatography (GPC) apparatus (SSC-7200) manufactured by Senshu Scientific Co., Ltd., and a column (KD-803, KD-805) manufactured by Shodex Co., Ltd. as follows. measuring.

Column temperature: 50 ° C

Dissolution: N,N'-dimethylformamide (lithium bromide-water and substance (LiBr.H ₂ O) as an additive 30 mmol/L, phosphoric acid. anhydrous crystal (o-phosphoric acid) 30 mmol/L, tetrahydrofuran (THF) ) 10ml / L)

Flow rate: 1.0ml/min

Standard sample for calibration line preparation: TSK standard polyethylene oxide (molecular weight about 9000000, 150,000, 100000, 30000) made by Tosoh Corporation, and polyethylene glycol (polymer molecular company) made by Polymer Research Institute (molecular weight about 12000, 4000, 1000).

<Example 1>

CBDA (7.4 g, 38 mmol) and ADA (14.4 g, 40 mmol) were mixed in NMP (87.5 g), and reacted at room temperature for 10 hours to obtain a polyaminic acid solution. To the polyamic acid solution, NMP (182.3 g) and BC (72.9 g) were added and diluted to 6 mass%, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent (A1). The polyamic acid contained in the liquid crystal alignment agent (A1) had a number average molecular weight of 8,000 and a weight average molecular weight of 19,500.

<Example 2>

CBDA (4.5 g, 23 mmol), ADA (4.3 g, 12 mmol), p-PDA (1.3 g, 12 mmol) were mixed in NMP (90.8 g), and reacted at room temperature for 10 hours to obtain a polyaminic acid solution. To the polyamic acid solution, NMP (33.6 g) and BC (33.6 g) were added and diluted to 6 mass%, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent (A2). The polyamic acid contained in the liquid crystal alignment agent (A2) had a number average molecular weight of 9,600 and a weight average molecular weight of 21,000.

<Comparative Example 1>

CBDA (7.5 g, 38.4 mmol) and DDM (7.9 g, 40 mmol) were mixed in NMP (87.6 g), and reacted at room temperature for 10 hours to obtain a polyaminic acid solution. To the polyamic acid solution, NMP (103.1 g) and BC (51.5 g) were added and diluted to 6% by mass, and liquid crystals were obtained by stirring at room temperature for 5 hours. Orienting agent (B1). The polyamic acid contained in the liquid crystal alignment agent (B1) had a number average molecular weight of 9,800 and a weight average molecular weight of 19,000.

<Comparative Example 2>

CBDA (7.5 g, 38 mmol) and terphenyl (10.4 g, 40 mmol) were mixed in NMP (160.8 g), and reacted at room temperature for 10 hours to obtain a polyaminic acid solution. To the polyamic acid solution, NMP (59.6 g) and BC (59.6 g) were added and diluted to 6 mass%, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent (B2). The polyamic acid contained in the liquid crystal alignment agent (B2) had a number average molecular weight of 8,000 and a weight average molecular weight of 18,000.

<Comparative Example 3>

CBDA (5.5 g, 29 mmol) and p-PDA (3.2 g, 30 mmol) were mixed in NMP (101.6 g), and reacted at room temperature for 10 hours to obtain a polyaminic acid solution. To the polyamic acid solution, NMP (7.4 g) and BC (29.4 g) were added and diluted to 6 mass%, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent (B3). The polyamic acid contained in the liquid crystal alignment agent (B3) had a number average molecular weight of 10,000 and a weight average molecular weight of 22,000.

<Example 3> [Evaluation of Light Resistance by Voltage Retention Rate (VHR) Measurement]

The liquid crystal alignment agent (A1) obtained in Example 1 was filtered through a 1.0 μm filter, and then spin-coated on a glass substrate with a transparent electrode, dried on a hot plate at 80 ° C for 5 minutes, and then fired at 250 ° C. Take 20 minutes A coating film having a film thickness of 100 nm was obtained. The polyimide film was rubbed with a crepe cloth (roller diameter: 120 mm, rotation number: 1000 rpm, moving speed: 30 mm/sec, and placed in an amount of 0.2 mm), and then subjected to ultrasonic irradiation for 1 minute in pure water at 80 ° C. Dry for 10 minutes. Two substrates with a liquid crystal alignment film were prepared, and a 6 μm spacer was placed on the liquid crystal alignment film surface of one of the substrates, and the rubbing directions of the two substrates were combined to be orthogonal, and the liquid crystal injection port was left to seal the periphery. The cell gap is 6 μm empty cell. Liquid crystal was injected into the cell at room temperature (MLC-2003 (C080), manufactured by Merck Japan Co., Ltd.), and the injection port was sealed to obtain a liquid crystal cell in which the liquid crystal was twisted and aligned by 90 degrees.

Thereafter, the VHR was evaluated.

In the evaluation of VHR, the obtained liquid crystal cell was applied with a voltage of 4 V for 60 μs at a temperature of 23 ° C, and the voltage after 16.67 ms was measured, and the amount of voltage maintained was calculated as the voltage holding ratio. Also, the same measurement was carried out at a temperature of 90 °C. Further, the voltage holding ratio was measured using a voltage holding ratio measuring device VHR-1 manufactured by Dongyang Technology Co., Ltd. The evaluation results are shown in Table 1.

Next, the liquid crystal cell was irradiated with ultraviolet rays 1J of 365 nm, and the VHR after the ultraviolet irradiation was similarly evaluated. The evaluation results are shown in Table 1.

The liquid crystal alignment agent (B1) obtained in Comparative Example 1 and the liquid crystal alignment agent (B2) obtained in Comparative Example 2 were used to produce liquid crystal cells in the same manner as in the case of using the above liquid crystal alignment agent (A1). The VHR before and after ultraviolet irradiation was evaluated. The evaluation results are shown in Table 1.

<Example 4> [Evaluation of optical alignment]

The liquid crystal alignment agent (A1) obtained in Example 1 was filtered through a 1.0 μm filter, and then spin-coated on a glass substrate with a transparent electrode, dried on a hot plate at 80 ° C for 5 minutes, and then subjected to hot air circulation at 220 ° C. The oven was fired in an oven for 30 minutes to form a coating film having a film thickness of 100 nm. The coating film surface was irradiated with ultraviolet rays of 254 nm at 500 mJ/cm ² through an oil polarizing plate to obtain a substrate with a liquid crystal alignment film.

In order to evaluate the electrical characteristics of the liquid crystal cell, two substrates having the liquid crystal alignment film described above were prepared, and a spacer of 4 μm was spread on one of the liquid crystal alignment film faces. From this, the sealing material is printed thereon, and the other substrate is faced to the liquid crystal alignment film surface, and the light alignment direction is bonded to the orthogonal direction, and then the sealing material is cured to form an empty cell. Liquid crystal MLC-2003 ((C080), manufactured by Merck Japan Co., Ltd.) was vacuum-injected into the empty cell at room temperature by a vacuum injection method, and the injection port was sealed to obtain a light alignment treatment of the liquid crystal by a 90 degree twist alignment. The liquid crystal cell. The liquid crystal cell was subjected to heat treatment at 105 ° C for 10 minutes, and then cooled to room temperature and observed for the unit cell, and the alignment property was good. The evaluation results are shown in Table 2.

Using the liquid crystal alignment agent (A2) obtained in Example 2, the production of liquid crystal cells was carried out in the same manner as in the case of using the above liquid crystal alignment agent (A1), and the alignment property was evaluated in the same manner. The evaluation results are shown in Table 2.

Using the liquid crystal alignment agent (B3) obtained in Comparative Example 3, the liquid crystal cell system was produced in the same manner as in the case of using the above liquid crystal alignment agent (A1). Create, evaluate the alignment in the same way. The evaluation results are shown in Table 2.

<Example 5> [Measurement of residual DC]

The measurement of residual DC was carried out by using the liquid crystal cell produced in Example 4 and a dielectric absorption method by a 6254 liquid crystal physical property evaluation apparatus manufactured by Dongyang Technology Co., Ltd., respectively. The measurement system was carried out in an environment of 60 ° C, and after applying a DC voltage of 10 V to the cell for 30 minutes, it was discharged for 1 second, and the residual DC amount after 20 minutes was rated as "good", and those of 500 mV or more were used. Named "bad". The evaluation results are shown in Table 2. In the liquid crystal cells produced in Example 4, the evaluation results of the liquid crystal cells produced by using the liquid crystal alignment agents (A1, A2) of Examples 1 and 2 were "good".

From the above, it can be seen that the liquid crystal display element of the present embodiment has a good charge retention rate even when subjected to ultraviolet irradiation, and the performance deterioration due to ultraviolet irradiation is also reduced.

Further, it is understood that the liquid crystal display element of the present embodiment not only achieves good alignment of the liquid crystal obtained by the photo-alignment treatment, but also has excellent residual DC characteristics, and the performance deterioration due to ultraviolet irradiation is also reduced.

[Industrial availability]

The liquid crystal display element of the present invention is a liquid crystal display element which is produced by irradiating ultraviolet rays through a region where a pixel is formed, but the deterioration of performance is suppressed. Therefore, excellent display characteristics and productivity can be achieved. Therefore, it can be suitably used for manufacture of a liquid crystal display element for a portable data terminal such as a large-sized liquid crystal TV or a smart phone that displays a high-definition image.

1‧‧‧Liquid display components

2‧‧‧TFT substrate

3‧‧‧CF substrate

4‧‧‧Liquid layer

5, 15‧‧‧ substrate

6‧‧‧ pixel electrodes

7‧‧‧CF layer

8‧‧‧Protective layer

9‧‧‧Colored layer

10‧‧‧Black matrix

11‧‧‧Common electrode

12‧‧‧Liquid alignment film

16‧‧‧ Sealing material

17‧‧‧Polar plate

Claims (13)

A liquid crystal display element comprising a liquid crystal alignment film in a region where a pixel is formed, and irradiating the formation region of the pixel with ultraviolet rays, wherein the liquid crystal alignment film is selected from the group consisting of the following formula (1) a polyimine precursor formed by the compound and at least one polymer of the polyimine obtained by imidating the oxime; The liquid crystal display element of claim 1, wherein the liquid crystal alignment film comprises a compound selected from the group consisting of the compound represented by the above formula (1) and a compound represented by the following formula (AM) (except for the compound represented by the above formula (1)) a formed polyimine precursor and at least one polymer of the polyimine obtained by imidating the oxime; In the formula (AM), Y ₁ is a divalent organic group, and two or more kinds may be mixed; and in the formula (AM), R ¹ and R ^{2 each} represent a hydrogen atom or a monovalent organic group. The liquid crystal display element of claim 1, wherein the liquid crystal alignment film comprises a polyimine precursor selected from at least one of the compounds represented by the following formulas (CB1) to (CB5) and At least one polymer of a polyamidimide obtained by amination; In the formulae (CB1) to (CB5), Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms, and contains a non-aromatic cyclic hydrocarbon group having 4 to 6 carbon atoms; in the formulae (CB4) and (CB5), R ³ represents a carbon number of 1 to 5, preferably an alkyl group having 1 to 2 carbon atoms. The liquid crystal display element of claim 2, wherein the liquid crystal alignment film comprises a polyfluorene imine precursor selected from at least one of the compounds represented by the following formulas (CB1) to (CB5) and At least one polymer of a polyamidimide obtained by amination; In the formulae (CB1) to (CB5), Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms, and contains a non-aromatic cyclic hydrocarbon group having 4 to 6 carbon atoms; in the formulae (CB4) and (CB5), R ³ represents a carbon number of 1 to 5, preferably an alkyl group having 1 to 2 carbon atoms. A method for producing a liquid crystal display device, which is characterized in that a liquid crystal display device having a liquid crystal layer and a liquid crystal alignment film in a region where a pixel is formed is characterized in that: a liquid crystal in which the liquid crystal alignment film is formed in a region where the pixel is formed An alignment film forming step of irradiating the formation region of the pixel with ultraviolet light after the step of forming the liquid crystal alignment film; wherein the liquid crystal alignment film comprises a compound selected from the group consisting of the compound represented by the following formula (1) a polyimide precursor and at least one polymer of the polyimine obtained by imidating the oxime; The method for producing a liquid crystal display element according to claim 5, wherein the liquid crystal alignment film comprises a compound selected from the group consisting of the compound represented by the above formula (1) and the compound represented by the following formula (AM) (expressed by the above formula (1) a polyimine precursor formed by the compound; and at least one polymer of the polyimine obtained by imidating the oxime; In the formula (AM), Y ₁ is a divalent organic group, and two or more kinds may be mixed; and in the formula (AM), R ¹ and R ^{2 each} represent a hydrogen atom or a monovalent organic group. The method for producing a liquid crystal display element according to claim 5, wherein the liquid crystal alignment film comprises a polyfluorene imide precursor selected from at least one of the compounds represented by the following formulas (CB1) to (CB5) and At least one polymer of the quinone imidized polyimine; In the formulae (CB1) to (CB5), Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms, and contains a non-aromatic cyclic hydrocarbon group having 4 to 6 carbon atoms; in the formulae (CB4) and (CB5), R ³ represents a carbon number of 1 to 5, preferably an alkyl group having 1 to 2 carbon atoms. The method for producing a liquid crystal display element according to claim 6, wherein the liquid crystal alignment film comprises a polyfluorene imide precursor selected from at least one of the compounds represented by the following formulas (CB1) to (CB5) and At least one polymer of the quinone imidized polyimine; In the formulae (CB1) to (CB5), Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms, and contains a non-aromatic cyclic hydrocarbon group having 4 to 6 carbon atoms; in the formulae (CB4) and (CB5), R ³ represents a carbon number of 1 to 5, preferably an alkyl group having 1 to 2 carbon atoms. The method for producing a liquid crystal display device according to any one of the preceding claims, wherein the liquid crystal alignment film forming step has a sealing forming step of forming a sealing material around the formation region of the pixel, and the light irradiation step The step of hardening the aforementioned sealing material in the aforementioned sealing forming step. The method of manufacturing a liquid crystal display element according to any one of claims 5 to 8, wherein the light irradiation step is a step of performing an alignment treatment on the liquid crystal alignment film. The method of manufacturing a liquid crystal display element according to any one of the preceding claims, wherein the liquid crystal alignment film forming step has a step of forming the liquid crystal layer in a region where the pixel is formed, and the light irradiation step drives the aforementioned At the same time as the liquid crystal of the liquid crystal layer, the formation of the aforementioned pixel The step of shooting ultraviolet light. The method of manufacturing a liquid crystal display device according to any one of claims 5 to 8, wherein the liquid crystal layer comprises a liquid crystal and a photopolymerizable compound, and the light irradiation step is performed on a formation region of the pixel. The step of polymerizing the aforementioned photopolymerizable compound of the liquid crystal layer. The method of manufacturing a liquid crystal display element according to claim 12, wherein the liquid crystal alignment film forming step has a step of forming the liquid crystal layer in the formation region of the pixel, and the light irradiation step drives the liquid crystal of the liquid crystal layer a step of irradiating ultraviolet rays to the formation region of the aforementioned pixels.