JP3301960B2 - Liquid crystal alignment film, method for manufacturing liquid crystal alignment film, liquid crystal display device, and method for manufacturing liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a liquid crystal alignment film having high density, good uniformity and excellent orientation stability. SOLUTION: A substrate 1 having an inorg. siloxane polymer film 3 formed on the surface of the electrode side is prepared, and the polymer film 3 is brought into contact with a silane-based surfactant containing straight carbon chains or straight siloxane bonding chains and photosensitive groups 7a to cause chemical reaction. Therefore, one end of the surfactant molecule is chemically bonded to the surface of the polymer film 3 to form a monomolecular coating film. Then the film is cleaned with a nonwater org. solvent, and the substrate 1 is drawn as tilted in a specified direction from the cleaning liquid to dewater the liquid and dried. Thus, the molecules are oriented in the dewatering direction. Then the film is irradiated with polarized UV rays 11 according to the pattern to produce a liquid crystal alignment film 71, 73.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal alignment film, a method for manufacturing a liquid crystal alignment film, a liquid crystal display device, and a method for manufacturing a liquid crystal display device. More specifically, for example, a liquid crystal alignment film used for a flat display panel using a liquid crystal for displaying a television (TV) image, a computer image, and the like, a method of manufacturing the liquid crystal alignment film, a liquid crystal display device, and a method of manufacturing the liquid crystal display device About.

[0002]

2. Description of the Related Art Conventionally, a color liquid crystal display panel is formed by spin-coating a polyvinyl alcohol, a polyimide solution or the like with a spinner or the like between two substrates having opposed electrodes arranged in a matrix. A device in which liquid crystal is sealed through an alignment film has been generally used.

As the apparatus, a device manufactured as described below is generally well known. For example, a thin film transistor (TFT) array having pixel electrodes formed on a first glass substrate in advance,
A plurality of red-blue-green color filters and a common transparent electrode laminated in this order on the glass substrate are prepared. Then, a polyvinyl alcohol or polyimide solution or the like is applied to each electrode side surface using a spinner to form a film, and then rubbing is performed to form a liquid crystal alignment film. After assembling and fixing the two substrates via a spacer while maintaining a certain gap, a liquid crystal (twisted nematic (TN) or the like) is injected to form a panel structure. Then, by installing a polarizing plate on the front and back of the panel and operating the TFT while irradiating the backlight from the back, a color image can be displayed.

As described above, a conventional liquid crystal alignment film is formed by dissolving polyvinyl alcohol, polyimide, or the like in an organic solvent, applying the solution to a substrate by a spin coating method or the like to form a film, and then applying a felt cloth. A so-called rubbing method has been used in which rubbing is performed by using such a method. But,
In this method, a surface step or a large area panel (for example, 14
Inch display), there is a problem that the uniformity of the liquid crystal alignment film is poor. Also, TFT for rubbing
Of the display, and dust generated by rubbing also causes display defects. Therefore, at present, a so-called rubbing-free method for binding a silane-based surfactant to the substrate surface and aligning it in a pattern is being studied for the preparation of a liquid crystal alignment film. However, since the production of the liquid crystal alignment film depends on the hydrophilicity of the substrate surface, it is difficult to form the liquid crystal alignment film on a hydrophobic substrate surface such as a SiN ₃ film or an indium oxide film (ITO film).

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a liquid crystal alignment film having a high density, a high uniformity, a high alignment stability of the molecules, and a rubbing process. Liquid crystal alignment film to be formed, method for manufacturing liquid crystal alignment film,
An object of the present invention is to provide a liquid crystal display device and a method of manufacturing the liquid crystal display device.

[0006]

In order to achieve the above object, the liquid crystal alignment film of the present invention is a monomolecular film formed on the electrode side surface of a substrate, and an inorganic siloxane film is formed on the electrode side surface. It has a configuration in which one end of a molecule formed through a polymer film and constituting the coating film is chemically bonded to the surface of the polymer film.

As described above, the liquid crystal alignment film of the present invention can be formed without performing rubbing, and is formed on the substrate via the polymer film. The molecules constituting the liquid crystal alignment film are chemically bonded to the polymer film at a high density, the uniformity is good, and the stability of the alignment regulating force of the molecules is excellent.
In the present invention, a monomolecular film (hereinafter also referred to as a “monomolecular film”) is a so-called monomolecular film, most of which is a monomolecular film, but is formed by partially laminating molecules. Including coatings.

In the liquid crystal alignment film of the present invention, it is preferable that chemically bonded molecules constituting the monomolecular film are aligned in one direction, and the molecules are polymerized.

In the liquid crystal alignment film of the present invention, the chemically bonded molecules constituting the monomolecular film are oriented in a plurality of different directions in a pattern, and the chemically bonded molecules are polymerized. Is preferred. The orientation in the pattern shape means, for example, in the case of orientation in two directions in a pattern shape, one pixel is divided into two, and one orientation direction is set to 0 ° direction, and the other orientation direction is set to the orientation direction. 18 for
For example, it may be 0 °.

In the liquid crystal alignment film of the present invention, the chemically bonded molecules constituting the monomolecular film include a photosensitive group, a linear carbon chain or a linear siloxane bonded chain, and silicon. Preferably, the chemically bonded molecules are polymerized at the photosensitive base. By polymerizing the molecules at the photosensitive base in this way, the alignment stability of the monomolecular film is excellent.

In the liquid crystal alignment film of the present invention, the monomolecular film is composed of a plurality of chemically bonded molecules of different lengths, and at least one of the chemically bonded molecules is photosensitive. It is preferable that the molecules include a group, the plurality of types of molecules are oriented in a predetermined direction, and the orientation is fixed by polymerizing the chemically bonded molecules at the photosensitive base. When the monomolecular film is composed of the molecules, the monomolecular film can control the alignment angle of liquid crystal molecules, and is excellent in alignment stability because it is polymerized.

In the liquid crystal alignment film of the present invention, the plurality of chemically bonded molecules having different lengths constituting the monomolecular film include a linear carbon chain or a linear siloxane bonded chain, The length of the molecule is controlled by the carbon chain or the siloxane bond chain, and by changing the mixing ratio of the molecule or by changing the length of the relatively short molecule, the inclination of the longest molecule relative to the substrate is reduced. It is preferable that the angle is controlled to be constant.

In the liquid crystal alignment film of the present invention, it is preferable that the chemically bonded molecules constituting the monomolecular film include silicon at its terminal. Thereby, the monomolecular film can have high peeling resistance.

Next, the method for producing a liquid crystal alignment film of the present invention is as follows.
Prepare a substrate having an inorganic siloxane polymer film formed on the electrode side surface, and contact a silane surfactant containing a linear carbon chain or a linear siloxane bond chain and a photosensitive group with the polymer film. A step of chemically bonding one end of the surfactant molecule to the surface of the polymer film by causing a chemical reaction to form a monomolecular film.
According to this manufacturing method, since the polymer film is formed on the substrate in advance, the hydrophilicity on the substrate is improved, and the liquid crystal alignment film is easily formed. Therefore, regardless of the rubbing method, it is possible to obtain a liquid crystal alignment film having a high density of molecules constituting the liquid crystal alignment film and excellent uniformity.

In the method for producing a liquid crystal alignment film according to the present invention,
Preferably, the inorganic siloxane polymer film is formed using an inorganic chlorosilane agent.

In the method for producing a liquid crystal alignment film according to the present invention,
After one end of the silane-based surfactant molecule is chemically bonded to the inorganic siloxane polymer film, it is washed with a non-aqueous organic solvent, pulled up from the washing liquid with the substrate oriented in a predetermined direction, and drained and dried. It is preferable that the method further includes a step of irradiating the chemically bonded surfactant molecules in the liquid draining direction, and then irradiating the molecules with patterned polarized light. According to the manufacturing method, it is possible to obtain a liquid crystal alignment film in which the molecules constituting the liquid crystal alignment film are aligned in a predetermined direction, and the alignment is fixed by polymerization of the molecules.

It is also preferable to carry out the above step at least twice. According to this manufacturing method, it is possible to obtain a liquid crystal alignment film in which molecules constituting the liquid crystal alignment film are aligned in a plurality of different directions in a pattern, and the molecules are polymerized.

Further, in the method for producing a liquid crystal alignment film of the present invention, it is preferable that irradiation of polarized light in a pattern is performed at least twice or more.

In the method for producing a liquid crystal alignment film according to the present invention,
It is preferable to use an inorganic chlorosilane agent represented by the following general formula (1) as the inorganic chlorosilane agent. Cl (SiCl ₂ O) n-SiCl ₃ (1) In the general formula (1), n is 0, 1, 2, or 3. It is also preferable to use two or more kinds of the inorganic chlorosilane agents represented by the general formula (1).

In the method for producing a liquid crystal alignment film according to the present invention,
As the silane-based surfactant, two or more kinds of silane-based surfactants having different molecular lengths were mixed and used, and the chemical bonding was performed by changing a mixing ratio of the two or more silane-based surfactants. It is preferable to control the inclination of the longest silane-based surfactant molecule with respect to the substrate to a certain angle.

In the method for producing a liquid crystal alignment film according to the present invention,
The silane-based surfactant has a photosensitive group, at least one of a linear carbon chain and a linear siloxane bonding chain,
It preferably contains at least one group selected from the group consisting of a chlorosilyl group, an alkoxysilyl group and an isocyanatesilyl group.

In the method for producing a liquid crystal alignment film of the present invention,
By changing the length of at least one of the linear carbon chain and the linear siloxane-bonded chain, the molecular length of the chemically bonded silane-based surfactant molecule is changed, and the longest chemically bonded silane-based It is preferable to control the inclination of the surfactant molecules with respect to the substrate.

In the method for producing a liquid crystal alignment film of the present invention,
The terminal or a part of the linear carbon chain or the linear siloxane bonding chain has a trifluoromethyl group, a methyl group, a vinyl group, an allyl group, an ethynyl group, a phenyl group, an aryl group, a halogen group, an alkoxy group, a cyano group. Group, amino group,
It preferably contains at least one group selected from the group consisting of a hydroxyl group, a carbonyl group, an ester group and a carboxyl group. As a result, the pretilt angle of the liquid crystal molecules can be controlled over a wider range.

In the method for producing a liquid crystal alignment film according to the present invention,
It is preferable that the non-aqueous organic solvent contains at least one group selected from the group consisting of an alkyl group, a fluorocarbon group, a carbon chloride group and a siloxane group. By using the organic solvent, a liquid crystal alignment film without contamination can be provided.

Next, in the liquid crystal display device of the present invention, the liquid crystal is sandwiched between two opposing substrates via a liquid crystal alignment film, and the liquid crystal alignment film is formed on at least one of the substrates on the electrode side. Formed through a siloxane polymer film,
The liquid crystal alignment film is a monomolecular film in which chemically bonded molecules constituting the liquid crystal alignment film are polymerized, and one end of the molecule is chemically bonded to the polymer film.

In the liquid crystal display device of the present invention, an inorganic siloxane polymer film is formed on each of the electrode-side surfaces of two opposing substrates provided with electrodes, and a monomolecular liquid crystal alignment film is formed through each of the inorganic siloxane polymer films. It is preferred that This liquid crystal display device has excellent display characteristics.

In the liquid crystal display device of the present invention, the liquid crystal alignment films are formed with different orientations in a pattern, and the alignment direction or tilt angle of the liquid crystal molecules in contact with the liquid crystal alignment film is controlled for each pattern. It is preferable to use a multi-domain liquid crystal display device.

In the liquid crystal display device of the present invention, it is preferable that the opposing electrode is an in-plane switching (IPS) type liquid crystal display device formed on one substrate surface. This liquid crystal display device has excellent viewing angle characteristics.

Next, according to the method of manufacturing a liquid crystal display device of the present invention, an inorganic siloxane polymer film is formed on the electrode side surface of a first substrate having a first electrode group placed in a matrix, A silane-based surfactant containing a linear carbon chain or a linear siloxane bond chain and a photosensitive group is brought into contact with the polymer film, and the surfactant molecule is chemically reacted with the polymer film surface to form the interface. A step of chemically bonding one end of an activator molecule to the surface of the polymer film to form a monomolecular film, a first substrate and a second substrate provided with the first electrode group, or the first substrate; The first substrate provided with the electrode group and the second substrate provided with the second electrode or the electrode group are adhered and fixed by facing each other with the respective electrode-side surfaces being inside with a predetermined gap therebetween, and Between the first and second substrates And a step of injecting the eutectic composition.

In the method of manufacturing a liquid crystal display device according to the present invention, it is preferable to form the inorganic siloxane polymer film using an inorganic chlorosilane agent, as in the method of manufacturing the liquid crystal alignment film.

In the method of manufacturing a liquid crystal display device according to the present invention, one end of the silane-based surfactant molecule is chemically bonded to the inorganic siloxane polymer film, and then washed with a non-aqueous organic solvent, and It is preferable that the method further includes a step of pulling out the cleaning liquid with the substrate facing and draining and drying the liquid so as to orient the chemically bonded surfactant molecules in the liquid draining direction.

In the method of manufacturing a liquid crystal display device according to the present invention, the silane-based surfactant molecules that are chemically bonded are oriented in a draining direction, and then irradiated with patterned polarized light a plurality of times to form the monomolecular film. Preferably, the method is a method for manufacturing a multi-domain liquid crystal display device, which comprises a step of orienting the chemically bonded surfactant molecules constituting the coating film in two or more places in different directions.

In the method of manufacturing a liquid crystal display device according to the present invention, the liquid crystal alignment film on each surface of the first substrate provided with the first electrode group and the second substrate provided with the second electrode or the electrode group is formed by each domain. 45-110 ° or 180-
It is preferable to use a method for manufacturing a twisted nematic (TN) type or super twisted nematic (STN) type multi-domain liquid crystal display device formed to have a 270 ° twist alignment. This makes it possible to provide a device having excellent viewing angle characteristics.

In the method of manufacturing a liquid crystal display device according to the present invention, the opposing electrodes are formed on one substrate surface.
It is preferable that the method is a method for manufacturing an IPS-type liquid crystal display device using a PS-type TFT array substrate as a first substrate having a first electrode group. Thus, a liquid crystal display device having excellent viewing angle characteristics can be provided.

In the method of manufacturing a liquid crystal display device according to the present invention, when forming the inorganic siloxane polymer film, an organic solvent containing the inorganic chlorosilane agent is applied to the substrate surface, and the organic solvent is evaporated. Is preferably reacted.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The liquid crystal alignment film of the present invention is, for example,
It can be manufactured as shown below. First, a substrate having an inorganic siloxane polymer film formed on the electrode side surface is prepared, and a silane-based surfactant containing a linear carbon chain or a linear siloxane bond chain and a photosensitive group is brought into contact with the polymer film. Causing a chemical reaction to cause one end of the surfactant molecule to chemically bond to the polymer membrane surface,
Form a monolayer. Then, after one end of the molecule is chemically bonded to the surface of the polymer film, the formed monomolecular film is washed using a non-aqueous organic solvent, pulled up from the washing solution with the substrate oriented in a predetermined direction, and After the molecules are oriented in the draining direction by cutting and drying, a step of irradiating the molecules with patterned polarized light is performed.

The above step is for orienting molecules constituting the monomolecular film in a predetermined direction and polymerizing the molecules. The orientation is preferably performed in a plurality of directions different from each other in a pattern, particularly preferably different directions.
4 directions. The following two methods are used as a method for orienting in a plurality of different directions in a pattern. One is a method in which the above step is performed two or more times, and it is preferable to perform the step two to four times. On the other hand, 1
This is a method in which the pattern-like polarized light irradiation is performed two or more times, whereas the polarized light irradiation is preferably performed two to four times. By performing these steps, the molecules constituting the monomolecular film are oriented in a plurality of different directions in a pattern, and the orientation is fixed by further polymerizing the molecules. A liquid crystal alignment film having high performance can be obtained. In addition, in the case where the lifting liquid drainage drying and the pattern-shaped polarized light irradiation are each performed once, a high-quality liquid crystal alignment film in which the molecules are aligned in one direction can be obtained.

As described above, the silane-based surfactant includes a photosensitive group, at least one chain selected from a linear carbon chain and a linear siloxane bond chain, a chlorosilyl group, It is preferable to use a silane-based surfactant containing at least one group selected from a silyl group and an isocyanatesilyl group. Examples of the photosensitive group include a cinnamoyl group, a chalcone group, and a methacryloyl group.

As described above, a mixture of two or more silane-based surfactants having different molecular lengths is used as the silane-based surfactant. It is preferable to control the inclination of the longest silane-based surfactant with respect to the substrate to a constant angle by changing the mixing ratio. The mixing ratio (weight ratio) is appropriately determined according to their molecular length. For example, the surfactant having the longest molecule: the surfactant having the shortest molecule = 10: 1.
It is preferable to mix in a weight ratio range of １ ： 1: 10.
The angle is 0 to 30 degrees or 80 to the substrate.
90 ° is preferred. Further, as described above, by changing the length of at least one molecular chain selected from the linear carbon chain and the linear siloxane bond chain, the molecular length is changed, and the longest molecule with respect to the substrate is changed. It is also preferable to control the inclination.

As described above, in the liquid crystal alignment film of the present invention, a plurality of types of molecules having different lengths constituting the monomolecular film include a linear carbon chain or a linear siloxane bond chain. Preferably, the length of the molecule is controlled by the carbon chain or the siloxane bond chain, and the inclination of the longest molecule with respect to the substrate is controlled to a constant angle by changing the mixing ratio of the molecule. The angle is particularly preferably in the range of 0 to 30 ° or 80 to 90 ° with respect to the substrate, as described above.

The length of the molecule is not particularly limited, but a relatively short molecule is usually a molecule having a length of 1 to 18 carbon atoms, and a relatively long molecule is usually A molecule having a length in the range of 14 to 28 carbon atoms.
The reason why there is an overlap in the range of the number of carbon atoms indicating the length of both molecules is to indicate the relative length between the plurality of types of molecules. For example, a molecule having 16 carbon atoms is
When one molecule has 18 carbon atoms, it is a relatively short molecule, and when one molecule has 14 carbon atoms,
It is a relatively long molecule.

The mixing ratio (weight ratio) of the long molecule and the short molecule is appropriately determined depending on the molecular length of the two molecules, and the mixing ratio of the long molecule to the short molecule = 10: 1 to 1:10. Preferably, they are mixed.

The thickness of the polymer film is 0.5 to
A range of 50 nm is preferred, and particularly preferred is 1 to 5 nm.
Range. The thickness of the liquid crystal alignment film is 0.5
Is preferably in the range of 1 to 3 nm, particularly preferably 1 to 2.5 nm.
nm range.

Next, the liquid crystal display device of the present invention can be manufactured, for example, as follows. After forming an inorganic siloxane polymer film on the electrode side surface of a first substrate having a first electrode group placed in a matrix, a linear carbon chain or a linear siloxane bond chain and a photosensitive group are formed. A silane-based surfactant containing a single molecule by contacting one end of the surfactant molecule with the polymer film surface by causing a chemical reaction between the surfactant molecule and the polymer film surface. Form a film. Thereafter, the substrate is washed with a non-aqueous organic solvent, and the substrate is oriented in a predetermined direction, pulled up from the organic solvent, drained and dried, and the monomolecular film is removed in a direction opposite to the pulling direction. Orient. Then, an exposure mask provided with a polarizing plate is superposed thereon, and polarized light irradiation is performed to reorient the molecules constituting the monomolecular film and polymerize the molecules.
Thereafter, if necessary, in the same manner as described above, the substrate is washed with the organic solvent, pulled up from the organic solvent, the molecules are oriented, and a series of steps of performing photopolymerization by polarized light irradiation twice. The above may be performed. In addition, in the same manner as in the above-described method for manufacturing a liquid crystal alignment film, the liquid drainage, pull-up and drying may be performed once, whereas the polarized light irradiation may be performed two or more times.
Thereby, the molecules can be oriented in a plurality of different directions in a pattern.

A first substrate and a second substrate provided with the first electrode group, or a first substrate provided with the first electrode group and a second substrate provided with the second electrode or the electrode group Are opposed to each other with a predetermined gap being maintained with their respective electrode-side surfaces facing inward, and are adhered and fixed using a spacer and an adhesive to produce a liquid crystal cell. Liquid crystal is injected between the two substrates of the liquid crystal cell, and a polarizing plate is disposed outside the two substrates.

[0046]

Next, the present invention will be described in more detail with reference to FIGS.

Example 1 As shown in FIGS. 1 and 2, an inorganic siloxane polymer film was formed on a substrate. First, a glass substrate 1 having a transparent (ITO) electrode formed on its surface was prepared, and this was thoroughly washed and degreased in advance. Then, the substrate 1 was dipped in a solution containing an inorganic chlorosilane agent for 1 minute in a dry atmosphere (5% humidity) so as to cover the entire surface of the substrate 1 including the electrodes.
The solution is prepared by dissolving an inorganic chlorosilane agent represented by the general formula Cl ₃ SiOSiCl ₃ in a well-dehydrated non-aqueous organic solvent (hexamethyldisiloxane (bp. 100 ° C.)) to a concentration of about 3% by weight. Prepared. The applicable concentration of the solution is typically in the range of 0.1 to 50% by weight, with the range of 1 to 5% by weight being most suitable. Then, the substrate 1 was taken out of the solution, and the non-aqueous organic solvent was evaporated in a dry atmosphere (about 5% humidity). As a result, an inorganic chlorosilane film 2 was formed on the surface of the substrate 1. In FIG. 1, reference numeral 2 denotes an inorganic chlorosilane film.

Thereafter, the inorganic chlorosilane agent on the surface of the substrate 1 is reacted with moisture by further exposing the substrate 1 to air containing moisture, and as shown in FIG. To form an inorganic siloxane polymer film 3 having a large number of hydroxyl groups.

As the inorganic chlorosilane agent, one
General formula Cl_ThreeSiOSiCl_ThreeIn addition to those represented by
Formula SiCl_Four, (SiCl_TwoO)_TwoSiCl_ThreeOr (Si
Cl _TwoO)_ThreeSiCl_Three Can also be used. This
Among them, the general formula (SiCl_TwoO)_TwoSiCl_Three Or
(SiCl_TwoO)_ThreeSiCl_Three Inorganic chlorosila represented by
When a surfactant is used, the effect of increasing hydroxyl groups on the electrode side surface is improved.
It was confirmed that the fruits were larger.

Next, as shown in FIGS. 3, 4 and 5, a monomolecular film was formed on the substrate 1, and molecules constituting the monomolecular film were oriented. As shown in FIG. 3, the substrate 1 was immersed in a chemical adsorption solution 4 for about one hour in a dry atmosphere (relative humidity 30% or less). Further, the chemical adsorption liquid 4 may be applied directly to the substrate 1. The chemical adsorption liquid 4 contains about 1% by weight of a silane-based surfactant (chemically-adsorbed substance) containing a photosensitive group, a linear carbon chain, and silicon and represented by the following general formula (2). The concentration was adjusted by dissolving in a well-dehydrated non-aqueous organic solvent (hexadecane). The linear carbon chain may be a hydrocarbon group or the like.

[0051]

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Thereafter, the substrate 1 is removed from the chemical adsorption liquid 4.
And washed with a well-dehydrated non-aqueous organic solvent (n-hexane) 5 for about 10 minutes as shown in FIG.
After the rotation, the substrate 1 is oriented in a predetermined direction,
The cleaning solution 5 was pulled up in the direction of arrow 6 (first pulling-up direction) and drained. Further, the substrate 1 is exposed to air containing water, and as shown in FIG. 5, the surfactant molecules chemically adsorbed on the polymer film 3 are reacted with water to form a monomolecular film 7 of about 1.8 nm. Formed with a thickness of In the figure, 7b shows the surfactant molecules constituting the monomolecular film, and 7a schematically shows a cinnamoyl group which is a photosensitive group of the surfactant molecules.

Incidentally, Fourier transform infrared spectroscopy (FTI)
R) According to the analysis, as shown in the figure, the surfactant molecules constituting the monomolecular film 7 are composed of a hydroxyl group on the surface of the polymer film 3 formed on the surface of the substrate 1 and siloxane of the surfactant. Polymer film 3 by covalent bonding with
And was pre-oriented in the direction opposite to the pulling direction 6 from the cleaning liquid 5, that is, in the draining direction.

In the above series of steps, a dehydrochlorination reaction occurs between the trichlorosilyl group (—SiCl ₃ ) of the surfactant and the hydroxyl group of the polymer film on the surface of the substrate 1, and The bond of equation (3) was created. In the following formula (3), n is an integer including 0, and X indicates the substrate 1.

[0055]

Embedded image

Subsequently, a bond represented by the following general formula (4) was formed by a reaction between the surfactant and moisture in the air. In the following formula (4), n is an integer including 0,
X indicates the substrate 1.

[0057]

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Next, as shown in FIGS. 6 to 10,
The monomolecular film was subjected to a reorientation treatment and an orientation fixing treatment. FIG.
As shown in FIG. 7, a first exposure photomask constituted by overlapping a partially shielded mask 8a and a polarizing plate 8 (HNP′B, manufactured by Polaroid, the same applies hereinafter) is prepared.
The photomask was superimposed on the monomolecular film 7 so that the polarization direction 9 was substantially parallel to the first pull-up direction 6. The superimposition of the two may be performed completely in parallel, or may be performed by, for example, being shifted by 3 ° with respect to the lifting direction 6. Then, an ultra-high pressure mercury lamp was used to apply 365 m of ultraviolet light (UV light) 11 at 100 mJ /
cm ² (first irradiation of polarized light). FIG.
In the figure, reference numeral 10 denotes an ITO electrode formed on the substrate 1, and the same parts as those in FIG. In FIG. 7, the same parts as those in FIGS. 5 and 6 are denoted by the same reference numerals.

According to the FTIR analysis, the monomolecular film 71 is irradiated with the polarized UV light 11 so that the molecules constituting the monomolecular film are reoriented in the first polarization direction 9 and the photopolymerization is performed. Proceeds to form a bond represented by the following general formula (5) between the molecules, and as shown in FIG. 7, in the polarized light irradiation portion 71 of the monomolecular film, the molecules are polymerized by the photosensitive base 7a. I confirmed that. In the following formula (5), n is an integer including 0, X is the substrate 1, and Y and Z are the other molecules that polymerize with the photosensitive base.

[0060]

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Thereafter, the substrate 1 was immersed again in the cleaning liquid 5 for about 5 minutes, and the substrate 1 was pulled up in a direction 61 (second pulling direction) opposite to the first pulling direction 6 and drained. According to the FTIR analysis, as shown in FIG. 8, the monomolecular film 71 polymerized by the first polarized light irradiation did not show any change. It was confirmed that preliminary reorientation was performed in the draining direction opposite to the second pulling-up direction 61. In FIG. 8, FIG.
The same reference numerals are given to the same parts as.

Subsequently, as shown in FIG. 9, a mask 8 for shielding the monomolecular film 71 on which the first polarized light irradiation has been performed from light is performed.
a and a polarizing plate 81 are overlapped to prepare a second photomask for exposure, and the polarization direction is set to the second pulling-up direction 61.
The photomask was superimposed on the monomolecular film so as to be substantially parallel to the above. The two may be overlapped completely in parallel, or may be shifted by 3 ° with respect to the pulling-up direction 61, for example. Then, the second polarized light irradiation was performed in the same manner as described above. 11 in the figure
Denotes UV light, and 73 denotes a monomolecular film which has been irradiated with polarized light for the second time, and the same parts as those in FIGS. 7 and 8 are denoted by the same reference numerals.

According to the FTIR analysis, as shown in FIG. 10, the monomolecular film 73 which was subjected to the second polarized light irradiation was the same as that after the first polarized light irradiation.
While being reoriented in the polarization direction 91 of the second UV irradiation,
It was confirmed that the photopolymerization had progressed. 10, the same parts as those in FIGS. 6, 8, and 9 are denoted by the same reference numerals. The arrows on the monomolecular films 71 and 73 indicate the orientation direction in each domain, and were parallel to the polarization directions 9 and 91, respectively. In addition, the same bond as in the general formula (4) is generated between the molecules by the polymerization, and as shown in FIG. 9, the monomolecular film 73 that has been subjected to the second polarized light irradiation has the photosensitive group 7a Was confirmed to be polymerized.

Next, using the two substrates on which the monomolecular films were formed, the two monomolecular films were combined so as to face each other, and a gap of 20 μm was maintained so that each exposed portion had antiparallel orientation. Adhesively fixed in the state,
The liquid crystal cell was assembled. Then, a nematic liquid crystal ZLI4792 (manufactured by Merck, the same applies hereinafter) is injected into this,
The alignment state of the liquid crystal molecules was confirmed. As a result, a liquid crystal test cell having no disclination and having the liquid crystal molecules uniformly aligned in the cell was obtained. The injected liquid crystal molecules have a pretilt angle of about 1 ° with respect to each of the substrates along the molecules constituting the monomolecular film, and the directions of pulling up from the cleaning liquid 5 and the directions opposite to the directions 61 and 61, respectively. And oriented parallel to the polarization directions 9 and 91, respectively. This result was consistent with the result of the FTIR analysis.

As described above, in this example, a liquid crystal alignment film could be formed at a high density by forming an inorganic siloxane polymer film on the surface of a substrate and increasing the number of hydroxyl groups on the surface of the substrate. In addition, without changing the composition of the material constituting the liquid crystal alignment film, the monomolecular film is aligned by changing the pulling direction from the cleaning liquid and the polarization direction of UV irradiation, and the alignment direction of the injected liquid crystal is controlled. Was completed.

It should be noted that if the terminal of the molecule constituting the monomolecular film as the liquid crystal alignment film contains silicon, it is suitable for producing a liquid crystal alignment film having high peel resistance. Also, a similar liquid crystal alignment film could be produced by using a substance containing at least one of an alkoxysilyl group and an isocyanate silyl group instead of the chlorosilyl group as the silane-based surfactant.

Further, a trifluoromethyl group, a methyl group,
Terminate at least one group selected from the group consisting of vinyl, allyl, ethynyl, phenyl, aryl, halogen, alkoxy, cyano, amino, hydroxyl, carbonyl, ester and carboxyl groups Or by using a linear carbon chain contained in part, the pretilt angle of the liquid crystal molecules changes according to the group,
The pretilt angle could be controlled over a wide range. The same result was obtained in the linear siloxane bonding chain by including the above group.

Further, by using a solvent containing at least one group selected from an alkyl group, a fluorocarbon group, a carbon chloride group and a siloxane group as the non-aqueous organic solvent, the alignment controllability is excellent. A liquid crystal alignment film was manufactured.

Comparative Example 1 The alignment performance of the liquid crystal alignment film was evaluated in the same manner as in Example 1, except that the step of forming the inorganic siloxane polymer film was omitted. As a result, many disclinations occurred on the ITO electrode, and a high-quality liquid crystal alignment film could not be formed. This is based on the ITO
It is considered that the reason is that the active hydrogen (in this case, -OH group) is small on the surface of the electrode.

(Example 2) Two chemisorbed substances represented by the above general formula (2) and the general formula CH ₃ (CH ₂ ) ₁₈ SiCl ₃ were mixed at a weight ratio of 1: 0.1 and 1: 0.2. The alignment performance of the liquid crystal alignment film was evaluated in the same manner as in Example 1 except that the two liquids were mixed at two mixing ratios. As a result, in the case where the chemisorbed substance mixed at the former weight ratio (1: 0.1) is used, in the liquid crystal cell manufactured by using the obtained liquid crystal alignment film, the injected liquid crystal molecules are the same as those of Example 1. Similarly to 1, the liquid crystal molecules were oriented in the opposite directions in each domain, and the pretilt angles of the liquid crystal molecules were 1.5 ° and 1.4 °, respectively. Similarly, in the case of using the latter chemisorbed substance mixed at a weight ratio (1: 0.2), the injected liquid crystal molecules are similarly oriented in the respective domains in the opposite directions, and The pretilt angles are 2.1 ° and 2.3, respectively.
°.

As described above, in the formation of a monomolecular film, the molecules constituting the monomolecular film are two types of molecules having different molecular lengths, and at least one of the molecules has a photosensitive group. Thus, it was confirmed that, even after the monomolecular film was formed, the film was oriented in a predetermined direction, and even if the molecules were polymerized by the photosensitive group, they had the function of a liquid crystal alignment film. Furthermore, the pretilt angle of the injected liquid crystal molecules could be controlled arbitrarily by changing the composition and the mixing ratio of the chemisorbed substance.

Even when a chemisorbed substance containing a linear siloxane bond chain is used as a molecule constituting the monomolecular film instead of a linear carbon chain, the liquid crystal alignment film having the same function, although the pretilt angle is different. Could be obtained. In addition, even when a silane-based surfactant containing at least one of an alkoxysilyl group and an isocyanatesilyl group was used instead of the chlorosilyl group, almost the same liquid crystal alignment film was obtained.

Example 3 Two chemical adsorbents represented by the general formula (2) and the general formula CH ₃ (CH ₂ ) ₂₂ SiCl ₃ were mixed at a weight ratio of 1: 0.1 to the above formula ( 2) In the same manner as in Example 1, except that two chemisorbents represented by the general formula CH ₃ (CH ₂ ) ₁₄ SiCl ₃ were used by mixing them in a weight ratio of 1: 0.1. The alignment performance of the liquid crystal alignment film was evaluated. As a result, when the former mixture was used, the injected liquid crystal molecules were oriented in the opposite direction in each domain, as in the above-described embodiment, and the pretilt angles of the liquid crystal molecules were 1.1 °, respectively. showed that. Similarly, in the latter mixture, the injected liquid crystal molecules were oriented in the opposite directions in the respective domains, and the pretilt angles of the liquid crystal molecules were 0.8 °, respectively. As described above, the pretilt angle of the injected liquid crystal molecules could be arbitrarily controlled by changing the length of the chemisorbed substance without changing the composition and the mixing ratio.

Example 4 The general formula (2) and the general formula C
A liquid crystal was prepared in the same manner as in Example 1, except that two chemisorbed substances represented by F ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ SiCl ₃ were mixed at a weight ratio of 1: 0.1. The alignment performance of the alignment film was evaluated. As a result, the injected liquid crystal molecules were oriented in the opposite directions in each domain, as in the above-described example, and the pretilt angle of the liquid crystal molecules was 89 °. As described above, it was confirmed that a liquid crystal alignment film that is vertically (homeotropic) aligned with respect to the substrate can be easily manufactured by mixing and using the chemisorbing substance containing a fluoro group.

Embodiment 5 A manufacturing process for actually manufacturing a liquid crystal display device using the liquid crystal alignment film will be described with reference to FIG.

First, as shown in FIG. 11, on a first substrate 14 having a first electrode group on which a plurality of electrodes 12 are mounted in a matrix and a transistor 13 for driving this electrode group, An inorganic siloxane polymer film was formed according to the same procedure as in Example 1, and a chemical adsorption solution previously prepared in the same manner as in Example 1 was applied to form a monomolecular film over the entire surface on the electrode side.

Then, the substrate 14 is washed with chloroform, which is a non-aqueous organic solvent. With the substrate 14 facing the gate base line, the substrate 14 is pulled up from the cleaning solution, drained and dried, and the monomolecular film is dried. Were oriented in the direction opposite to the first pulling-up direction (draining direction). Subsequently, the monomolecular film on each electrode 12 of the electrode group is divided into four in a checkered pattern, and a mask having a light-shielding pattern having an opening only in the first divided part and a polarizing plate are overlapped with each other as described above. The exposure mask is set so that the pulling direction and the polarization direction are parallel to each other.
4 was aligned on the monolayer. And the substrate 1
4 from the vertical direction using a 500 W ultra-high pressure mercury lamp
nm (i-line) UV light (3.6 mJ / cm after passing through a polarizing plate)
² ) was irradiated with polarized light for 45 seconds (first polarized light irradiation). The monomolecular film on the electrode 12 divided into four parts was divided into the remaining second, third and fourth divided parts and irradiated with polarized light in order as shown below.

Further, the substrate 14 is immersed again in the cleaning liquid for 5 minutes, pulled up in the direction opposite to the first pulling-up direction, and dried, and the unexposed portion of the monomolecular film is removed in the second draining direction. Oriented. Then, the exposure mask was aligned with the second divided portion in the same manner as described above, and the second irradiation was performed in the same manner as the first polarized light irradiation.

Further, once again, the substrate was added to the same cleaning solution for 5 minutes.
The film was dipped for 1 minute, pulled up in a direction perpendicular to the first and second liquid draining directions, and then dried. The unexposed portion of the monomolecular film was oriented in the third liquid draining direction. Then, the exposure mask was aligned with the third divided portion in the same manner as described above, and the third polarized light irradiation was performed in the same manner as the polarized light irradiation.

Lastly, once again, the substrate was placed in the same cleaning solution for 5 minutes.
The film was immersed for a minute, pulled up in the direction opposite to the third drainage direction, and dried, and the unexposed portion of the monomolecular film was oriented in the fourth drainage direction. And, as above,
The exposure mask was aligned with the fourth divided portion, and the fourth polarized light irradiation was performed in the same manner as the polarized light irradiation. As a result, as shown in FIG.
Thus, a liquid crystal alignment film 18 oriented in different directions by ゜ could be produced. In the figure, 25 indicates the direction of the gate base line, and 26 indicates the alignment direction of each domain of the liquid crystal alignment film. On the other hand, in the same manner as described above, a liquid crystal alignment film 181 in which the domains of the four divided pixels are anti-parallel aligned with respect to the liquid crystal alignment film 18 is formed on the second substrate having the color filter 15 and the second electrode 16. 17 surfaces. In FIG. 11, the color filter 1
The green, blue, and red color filter portions constituting No. 5 are indicated by symbols G, B, and R, respectively.

Next, the electrodes 12 and 16 of the first and second substrates 14 and 17 are positioned so as to face each other, and the substrates 14 and 17 are
And an adhesive 20 were used to adhere and fix while maintaining a gap of about 5 μm, thereby producing a liquid crystal cell. And the first
And the respective liquid crystal alignment films 1 on the second substrates 14 and 17
8 and 181, the nematic liquid crystal 21 was injected, and polarizing plates 22 and 23 were combined on both surfaces of the liquid crystal cell to produce a multi-domain liquid crystal display device.

As a result, the pretilt angle of the liquid crystal molecules was almost 1 ° in each domain. Further, as shown in FIG. 12, the alignment direction was shifted by 90 ° for each domain of the liquid crystal alignment film. As shown in FIG. 11, such a device was able to display an image in the direction of arrow A by driving each transistor using a video signal while irradiating the backlight 24 over the entire surface. Also,
The viewing angle at this time could be secured up to about 140 degrees in the left, right, up, and down directions.

In the manufacture of the liquid crystal display device, the alignment direction of each domain in the liquid crystal alignment film 181 on the second substrate 17 facing the first substrate 14 is changed by the liquid crystal alignment on the first substrate 14. The two liquid crystal alignment films 1 are oriented such that they are respectively twisted by 90 ° with the alignment direction of the film 18.
By aligning 8,181, a TN-type multi-domain liquid crystal display device could be manufactured. The liquid crystal alignment films 18 and 18 on the surfaces of the first and second substrates 14 and 17 are also provided.
1, the orientation direction of each domain is 45-1
By positioning the two liquid crystal alignment films 18 and 181 in a direction of being twisted by 10 ° (excluding 90 °) or 180 to 270 °, an STN-type multi-domain liquid crystal display device could be manufactured. When an IPS-type TFT array in which opposing electrodes are formed on one substrate surface is used as a first substrate and a two-divided multi-domain liquid crystal alignment film is formed, an IPS multi-domain liquid crystal display device is manufactured. did it.

In the above-described embodiment, 365-nm UV light, which is i-line of an extra-high pressure mercury lamp, is used as light for exposure. However, 436 nm and 405 nm are used in accordance with the degree of light absorption of the substance constituting the liquid crystal alignment film. 254nm light or Kr
It is also possible to use 248 nm light obtained with an F excimer laser. In particular, light of 248 nm and 254 nm has high alignment efficiency because it is easily absorbed by most substances.

Further, in addition to a photosensitive group, a linear carbon chain, a linear siloxane bond chain and silicon,
Further, by incorporating a nematic liquid crystal structure or a ferroelectric liquid crystal structure having a specific surface energy, it was possible to further increase the alignment regulating force.

[0086]

As described above, the liquid crystal alignment film of the present invention has
The molecules constituting this are high in density, good in uniformity, and excellent in the orientation stability of the molecules. Further, according to the method for producing a liquid crystal alignment film of the present invention, a high-performance liquid crystal alignment film of the present invention can be efficiently produced without causing the defects generated in the conventional rubbing step. Such a liquid crystal alignment film can incorporate a nematic liquid crystal or a ferroelectric liquid crystal having a specific surface energy, and the liquid crystal display device of the present invention using the liquid crystal alignment film of the present invention has a predetermined tilt angle. , Extremely low cost and highly reliable wide viewing angle display is possible.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a state where a substrate is treated with an inorganic chlorosilane agent in one embodiment of the present invention.

FIG. 2 is a schematic view showing the formation of an inorganic siloxane polymer film in the example.

FIG. 3 is a cross-sectional view showing a state in which the substrate is immersed in a chemical adsorption solution in the embodiment.

FIG. 4 is a cross-sectional view showing a state of an alignment process in which the substrate is cleaned and the substrate is pulled up from a cleaning liquid in the embodiment.

FIG. 5 is a schematic view showing a molecular orientation state of a monomolecular film formed on a substrate surface in the example.

FIG. 6 is a schematic view showing a photo-alignment treatment in the embodiment.

FIG. 7 is a schematic diagram showing a first photo-alignment treatment in the embodiment.

FIG. 8 is a schematic view showing a second alignment process in the embodiment.

FIG. 9 is a schematic view showing a second photo-alignment treatment in the above embodiment.

FIG. 10 is a schematic diagram showing the state of molecular orientation of a monomolecular film that has been subjected to photoalignment twice in the above example.

FIG. 11 is a sectional view of a liquid crystal display device manufactured in another embodiment of the present invention.

FIG. 12 is a schematic diagram showing a liquid crystal alignment direction of a four-divided multi-domain pixel in the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Inorganic chlorosilane film 3 Inorganic siloxane polymer film 4 Chemical adsorption solution 5 Nonaqueous organic solvent for washing 6 First pulling direction 61 Second pulling direction 7 Monomolecular film 7a Photosensitive base 7b Surfactant molecule 71 First time 72 Photopolymerized monomolecular film 72 Second pre-oriented monomolecular film 73 Second photopolymerized monomolecular film 8, 81 Polarizer 8a Light-shielding mask 9, 91 Polarization direction 10 Transparent (ITO) electrode 11 UV light 12 electrode 13 transistor 14 first substrate 15 color filter 16 second electrode 17 second substrate 18, 181 liquid crystal alignment film 19 spacer 20 adhesive 21 liquid crystal 22, 23 polarizing plate 24 backlight 25 gate base line Direction 26 Orientation direction

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Nomura 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-7-114029 (JP, A) JP-A-Heisei 6- 230394 (JP, A) JP-A-4-356020 (JP, A) JP-A-3-7913 (JP, A) JP-A-4-13115 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) G02F 1/1337

Claims (30)

(57) [Claims] 1. A monomolecular film-like film formed on an electrode side surface of a substrate, wherein said silicon film is formed on said electrode side surface via an inorganic siloxane polymer film and comprises said film.
A liquid crystal alignment film in which one end of a molecule containing is chemically bonded to the surface of the polymer film. 2. The liquid crystal alignment film according to claim 1, wherein the chemically bonded molecules constituting the monomolecular film are aligned in one direction, and the molecules are polymerized. 3. The liquid crystal alignment film according to claim 1, wherein the chemically bonded molecules constituting the monomolecular film are oriented in a plurality of different directions in a pattern, and the chemically bonded molecules are polymerized. . 4. The chemically bonded molecules constituting a monomolecular film include a photosensitive group, a linear carbon chain or a linear siloxane bonded chain, and silicon, and the chemically bonded molecules are separated from each other. 4. The liquid crystal alignment film according to claim 2, wherein the polymer is polymerized at the photosensitive base. 5. A monomolecular film-like coating comprising a plurality of types of chemically bonded molecules having different lengths, wherein at least one of the chemically bonded molecules contains a photosensitive group, and The liquid crystal alignment film according to any one of claims 1 to 3, wherein the molecules are oriented in a predetermined direction, and the molecules that are chemically bonded to each other are fixed by polymerizing in the photosensitive base. . 6. A plurality of chemically bonded molecules having different lengths constituting a monomolecular film include a linear carbon chain or a linear siloxane bonded chain, and the length of the molecule is the carbon chain. Alternatively, the inclination of the longest molecule with respect to the substrate is controlled to a constant angle by controlling the siloxane bond chain and changing the mixing ratio of the molecules or changing the length of the relatively short molecules. Claim 5
The liquid crystal alignment film as described in the above. 7. The liquid crystal alignment film according to claim 1, wherein the chemically bonded molecule constituting the monomolecular film contains silicon at its terminal. 8. A substrate having an inorganic siloxane polymer film formed on an electrode side surface is prepared, and a silane-based surfactant containing a linear carbon chain or a linear siloxane bond chain and a photosensitive group is added to the polymer. A method for producing a liquid crystal alignment film in which one end of the above- mentioned surfactant molecule containing silicon is chemically bonded to the surface of the above-mentioned polymer film by causing a chemical reaction to occur in contact with the film to form a monomolecular film. 9. The method according to claim 8, wherein the inorganic siloxane polymer film is formed using an inorganic chlorosilane agent. 10. After chemically bonding one end of a silane-based surfactant molecule to an inorganic siloxane polymer film, washing is performed using a non-aqueous organic solvent, and the substrate is oriented in a predetermined direction. The method for producing a liquid crystal alignment film according to claim 8 or 9, further comprising a step of aligning the chemically bonded surfactant molecules in the liquid draining direction by cutting and drying, and irradiating the liquid crystal with patterned polarized light. 11. A method for producing a liquid crystal alignment film, wherein the step according to claim 10 is performed at least twice. 12. The method for producing a liquid crystal alignment film according to claim 10, wherein irradiation of polarized light in a pattern is performed at least twice. 13. The method for producing a liquid crystal alignment film according to claim 9, wherein an inorganic chlorosilane agent represented by the following general formula (1) is used as the inorganic chlorosilane agent. Cl (SiCl ₂ O) n-SiCl ₃ (1) In the general formula (1), n is 0, 1, 2, or 3. 14. The method for producing a liquid crystal alignment film according to claim 9, wherein two or more kinds of inorganic chlorosilane agents represented by the following general formula (1) are used as the inorganic chlorosilane agent. Cl (SiCl ₂ O) n-SiCl ₃ (1) In the general formula (1), n is 0, 1, 2, or 3. 15. As a silane-based surfactant, two or more silane-based surfactants having different molecular lengths are mixed and used, and the mixing ratio of the two or more silane-based surfactants is changed. The method for producing a liquid crystal alignment film according to any one of claims 8 to 14, wherein the inclination of the longest chemically bonded silane-based surfactant molecule with respect to the substrate is controlled at a constant angle. 16. A silane-based surfactant comprising: a photosensitive group;
16. The method according to claim 8, comprising at least one of a linear carbon chain and a linear siloxane bonding chain, and at least one group selected from the group consisting of a chlorosilyl group, an alkoxysilyl group and an isocyanatesilyl group. The method for producing a liquid crystal alignment film according to claim 1. 17. By changing the length of at least one of the linear carbon chain and the linear siloxane bonding chain,
The liquid crystal alignment film according to any one of claims 8 to 16, wherein the molecular length of the chemically bonded silane-based surfactant molecule is changed to control the inclination of the longest chemically bonded silane-based surfactant molecule with respect to the substrate. Manufacturing method. 18. A terminal or a part of a linear carbon chain or a linear siloxane bonding chain is a trifluoromethyl group,
At least one selected from the group consisting of methyl, vinyl, allyl, ethynyl, phenyl, aryl, halogen, alkoxy, cyano, amino, hydroxyl, carbonyl, ester and carboxyl groups The method for producing a liquid crystal alignment film according to any one of claims 8 to 17, comprising a group. 19. The non-aqueous organic solvent contains at least one group selected from the group consisting of an alkyl group, a fluorocarbon group, a carbon chloride group and a siloxane group.
The method for producing a liquid crystal alignment film according to any one of the above. 20. A liquid crystal is sandwiched between two opposing substrates via a liquid crystal alignment film, and the liquid crystal alignment film is formed on an electrode side surface of at least one of the substrates via an inorganic siloxane polymer film, The liquid crystal display device, wherein the liquid crystal alignment film is a monomolecular film formed by polymerization of molecules containing chemically bonded silicon constituting the liquid crystal alignment film, and one end of the molecule is chemically bonded to the polymer film. 21. An inorganic siloxane polymer film is formed on each electrode-side surface of two opposing substrates provided with electrodes, and a monomolecular liquid crystal alignment film is formed via each of the inorganic siloxane polymer films. The liquid crystal display device according to the above. 22. The liquid crystal display device according to claim 20, wherein the liquid crystal alignment film is formed with different alignments in a pattern, and the alignment direction or tilt angle of the liquid crystal molecules in contact with the liquid crystal alignment film. Is a multi-domain liquid crystal display device controlled for each pattern. 23. The in-plane switching type liquid crystal display device according to claim 20, wherein the opposing electrodes are formed on one substrate surface. 24. After forming an inorganic siloxane polymer film on an electrode-side surface of a first substrate having a first electrode group placed in a matrix, the first substrate has a linear carbon chain or a linear siloxane bond chain. A silane-based surfactant containing a photosensitive group is brought into contact with the polymer film, and one end of the surfactant molecule is formed by chemically reacting the surfactant molecule containing silicon with the polymer film surface. A step of forming a monomolecular film by chemically bonding to the surface,
A first substrate and a second substrate provided with the first electrode group, or a first substrate provided with the first electrode group and a second substrate provided with the second electrode or the electrode group, respectively. Adhering and fixing the liquid crystal composition with the side surfaces facing inward while keeping a predetermined gap therebetween, and injecting a liquid crystal composition between the first and second substrates. 25. The method according to claim 24, wherein the inorganic siloxane polymer film is formed using an inorganic chlorosilane agent. 26. After chemically bonding one end of a silane-based surfactant molecule to an inorganic siloxane polymer film, the substrate is washed with a non-aqueous organic solvent, and pulled up from the cleaning solution with the substrate oriented in a predetermined direction. 26. The method for manufacturing a liquid crystal display device according to claim 24, further comprising a step of aligning the chemically bonded surfactant molecules in the draining direction by cutting and drying. 27. The method for manufacturing a liquid crystal display device according to claim 26, wherein after the chemically bonded silane-based surfactant molecules are oriented in a draining direction, a pattern of polarized light is irradiated a plurality of times. And a step of aligning the chemically bonded surfactant molecules constituting the monomolecular film in different directions at two or more locations. 28. The method for manufacturing a liquid crystal display device according to claim 24, wherein the first substrate provided with the first electrode group and the second substrate provided with the second electrode or the electrode group are provided. 2. A method of manufacturing a TN-type or STN-type multi-domain liquid crystal display device, wherein a liquid crystal alignment film on each surface of a substrate of No. 2 is formed to be twisted at 45 to 110 ° or 180 to 270 ° in each domain. 29. The method for manufacturing a liquid crystal display device according to claim 24, wherein the in-plane switching TFT array substrate in which opposing electrodes are formed on one of the substrate surfaces. A method for manufacturing an in-plane switching type liquid crystal display device used as a first substrate having one electrode group. 30. The method according to claim 24, wherein, in the step of forming the inorganic siloxane polymer film, an organic solvent containing an inorganic chlorosilane agent is applied to the surface of the substrate, and the organic solvent is evaporated and then reacted with water. A method for manufacturing the liquid crystal display device according to claim 1.