JPS61277923A - Production of liquid crystal sandwiching substrate - Google Patents

Abstract

PURPOSE:To prevent the partial inconspicuousness and disablement of the display of a large-sized liquid crystal cell even if such cell is formed and to improve remarkably the response speed thereof by dispersing the pulverous particles of a tin oxide into a liquid crystal orienting film. CONSTITUTION:Part of the diamino compd. consisting essentially of the compd. expressed by the formula A is substd. with the diaminosiloxane compd. expressed by the formula B prior to reaction in the stage of bringing an org. tetracarboxylic acid and the diamino compd. into reaction. A polyimide soln. is prepd. by bringing the diaminosiloxane compd. and the remaining diamino compd. into reaction with the org. tetracarboxylic acid in an org. solvent. The tin compd. having at least either of a hydrolyzable functional group and oxidation decomposable functional group is compounded with such polyimide soln. The polyimide soln. compounded with the tin compd. is used as the soln. for forming the liquid crystal orienting film.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a liquid crystal sandwiching substrate that is a component of a liquid crystal cell.

[Conventional technology]

A liquid crystal cell is constructed by arranging two liquid crystal holding substrates having transparent electrodes with the transparent electrodes facing each other, covering the gap with a sealing material, and sealing the liquid crystal inside. The transparent electrodes of the liquid crystal sandwiching substrate are covered with a liquid crystal alignment film (insulating film) for the purpose of preventing the liquid crystal from directly contacting the transparent electrodes and causing liquid crystal deterioration.

Conventionally, silicon oxide films and organic polymer films have been used as this type of liquid crystal alignment film. The above-mentioned silicon oxide film has selectivity with respect to liquid crystal, and it is not easy to form a uniform film, so it is difficult to form a large uniform surface, and its use is gradually becoming obsolete. Therefore, recently, emphasis has been placed on organic polymer films, but organic polymer films are important in terms of maintaining the rubbing effect due to thermal deterioration during assembly, and improving moisture resistance, heat resistance, etc. of manufactured liquid crystal cells. Since then, polyimide resin membranes have come to be used. However, since the polyimide resin film has poor adhesion to the surface of a substrate (such as a glass plate), there is a problem that the film may partially peel off and cause alignment defects in the liquid crystal cell.

In addition, polyimide resin itself has a high volume resistivity value, and is usually IQIs ~ 10'? Because of the Ω value, in liquid crystal cells with elongated electrodes, the applied voltage becomes weaker at the ends of the electrodes, which causes the voltage applied to the liquid crystal in that area to drop below the threshold voltage, causing the display to partially disappear. It also has the disadvantage of being physically impossible. Recently, technological innovation has progressed in the field of liquid crystal cells, and the dimensions of liquid crystal cells have become larger.Therefore, there has been a strong demand for a solution to the above-mentioned problem of not being able to display images at the electrode ends. Also, there is a demand for fast response devices, as seen in liquid crystal switches (optical switches).

This invention was made in view of the above circumstances, and aims to provide a liquid crystal alignment film that has good adhesion, maintains its initial performance for a long period of time, and provides clear display to the edges even if it is of large size. The object of the present invention is to provide a method for manufacturing a liquid crystal sandwiching substrate that can form a liquid crystal cell with fast response.

[Means for solving problems]

In order to achieve the above object, the manufacturing method of the liquid crystal sandwiching substrate of the present invention is based on organic tetracarboxylic acids and the following general formula (A).
When reacting with a diamino compound whose main component is a compound represented by the formula (B), a part of the diamino compound is replaced with a diamino siloxane compound represented by the following general formula (B) prior to the reaction, and this diamino siloxane is A polyimide solution is prepared by reacting the compound and the remaining diamino compound with the organic tetracarboxylic acids in an organic solvent, and at least one of a hydrolyzable functional group and an oxidatively decomposable functional group is added to the polyimide solution. A configuration is adopted in which a tin compound having one of these is blended, and a polyimide solution containing this tin compound is used as a solution for forming a liquid crystal alignment film.

(A)...-H! No-o-χ-o-NH That is, the inventor replaced a part of the diamino compound as a starting material with a diaminosiloxane compound when producing a polyimide solution for forming a liquid crystal alignment film, and replaced these with an organic tetra When a liquid crystal alignment film is formed using the polyimide solution obtained by reacting with carboxylic acids, the liquid crystal alignment film firmly adheres to the substrate, suppressing the occurrence of peeling phenomenon and making it possible to use it for a long time. It has also been found that malfunctions caused by deterioration of liquid crystals can be avoided. As a result of further research, it was found that when a tin compound having one or both of a hydrolyzable functional group and an oxidatively decomposable functional group is added to the polyimide solution, the volume resistivity value of the liquid crystal alignment film can be significantly increased. The present inventors have discovered that the phenomenon of blurring or inability to display a partial display of a liquid crystal cell can be resolved, and that the response speed can be improved, and the present invention has been achieved.

The polyimide solution used in this invention contains organic tetracarboxylic acids, a diamino compound whose main components are the compound represented by the above general formula (8), and a diaminosiloxane compound represented by the above general formula (B). and a tin compound having at least one of a hydrolyzable functional group and an oxidatively decomposable functional group.

Here, the term "main component" is intended to include the case where the whole is composed of only the main component.

The above-mentioned organic tetracarboxylic acids have two sets of two IMI acid groups bonded to adjacent carbon atoms in the basic skeleton, that is, a total of four acid groups, and are aromatic, aliphatic or alicyclic tetracarboxylic acids. These include carboxylic acids and their esters, amides, halides, -anhydrides, dianhydrides, and other derivatives. These compounds may be used alone or
There is no problem even if two or more types are used together. Among the above organic tetracarboxylic acids, aromatic tetracarboxylic dianhydride is most preferred.

Representative examples of such aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 3.3', 4,
4°-benzophenonetetracarboxylic acid, 3.3'
, 4.4'-biphenyltetracarboxylic dianhydride, 2,3,3°, 4°-biphenyltetracarboxylic dianhydride, 2,3,6° 7-naphthalenetetracarboxylic dianhydride, ■.

2.5.6-Naphthalenetetracarboxylic dianhydride, 1
．． 4.5.8-naphthalenetetracarboxylic dianhydride,
2.2-bis(3,4-dicarboxyphenyl)pukopanni anhydride, bis<3,4-dicarboxyphenyl)sulfonyl hydrate, S.

4.9.10-Perylenetetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, 2.2-bis(2,3-dicarboxyphenyl)propani dianhydride, 1.1- Bis(2,3-dicarboxyphenyl)ethanihydride, 1,1-bis(3,4-dicarboxyphenyl)ethannihydride, benzene-1,2
, 3,4-tetracarboxylic dianhydride, 2,3.6.7
-Anthracentetracarboxylic dianhydride, 1.2°7
．． Examples include 8-phenanthrenetetracarboxylic dianhydride.

The general formula (
Specific examples of the compound represented by A) include:
4.4°-di(m-aminophenoxy)diphenylsulfone, 4,4"-di<p-aminophenoxy)diphenylsulfone, 4.4"-di(m-aminophenoxy)diphenyl ether, 4,4"-di (p-aminophenoxy)diphenyl ether, 4,4'-di(m-aminophenoxy)diphenylpropane, 4.4'-di(p-aminophenoxy)diphenylpropane, 4.4'-di(
m-aminophenylsulfonyl) diphenyl ether,
4. 4'-di(p-aminophenylsulfonyl) diphenyl ether, 4,4'-di(m-aminophenylthioether) diphenyl sulfide, 4,4'-di(p
-aminophenylthioether) diphenyl sulfide, 4.4'-di(m-aminophenoxy) diphenyl ketone, 4,4'-di(p-aminophenoxy) diphenyl ketone, 4.4'-di(m-aminophenoxy) ) diphenylmethane, 4,4'-di(p-aminophenoxy)
Diphenylmethane, 4,4°-di(m-aminophenoxy)biphenyl, 4.4′-di(p-aminophenoxy)biphenyl, 4.4′-di(m-aminophenyl)biphenyl, 4. 4'-di(p-aminophenylsulfonyl)biphenyl, 4. Examples include 4'-di(m-aminophenylthioether)biphenyl, 4,4'-di(p-aminophenylthioether)biphenyl, and the like.

In the present invention, the diamino compound mainly having the general formula (A) to be reacted with organic tetracarboxylic acids may be a diamine represented by the general formula (A) entirely, but other diamines may be used. It may be used by partially substituting the diamine represented by the above general formula (A). However, since its excessive use impairs the properties of the obtained liquid crystal aligning film, its replacement amount should be limited to 10 mol%.

Other diamines mentioned above include meta-phenylene diamine, para-phenylene diamine, meta-tolylene diamine,
para-tolylene diamine, 4.4゛-diaminodiphenylmethane, 4,4゛-diaminodiphenyl ether, 2
, 2°-bis(4-aminophenyl)propane, 3.3
° -Diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfide, benzidine, benzidine-3,3
゛-dicarboxylic acid, benzidine-3,3゛-disulfonic acid, benzidine-3-monocarboxylic acid, benzidine-3-monosulfonic acid, 3,3'-dimethoxy-benzidine, mecubis(4-aminophenoxy)benzene, Para-bis(4-aminophenoxy)benzene, meta-xylylene diamine, para-xylylene diamine, etc. can be mentioned, and these can also be used alone or in combination of two or more.

The diaminosiloxane compound represented by the general formula (B) above, together with the diamino compound represented by the general formula (A) above, reacts with the organic tetracarboxylic acids and is introduced into the molecular skeleton of the reaction product. 0 For example, pyromellitic dianhydride is used as the organic tetracarboxylic acid, 4.4″-di(p-aminophenoxy)diphenylsulfone is used as the diamino compound, and the diaminosiloxane compound is represented by the following general formula. The structural formula of the product used is as represented by the following general formula (D).

(The following is a blank space) Representative examples of the diaminosiloxane compound represented by the above general formula (B) are as follows.

H3C1h The polyimide solution used in this invention can be obtained by reacting the above diaminosiloxane compound and a diamino compound whose main component is the compound represented by the above general formula (A) with an organic tetracarboxylic acid in an organic solvent. It can be manufactured by

Examples of the organic solvent include N-methyl-2=pyrrolidone, N,N'-dimethylacetamide, N,N'
-Dimethylformamide, dimethylsulfoxide, hexamethylphosphoramide, etc. Further, in place of some of these solvents, general-purpose solvents such as toluene, xylene, benzonitrile, benzene, and phenol may be used. However, the amount used must be regulated within a range that does not reduce the solubility of the product.

When the polyimide solution obtained in this manner is formed into a polyimide alignment film, the diaminosiloxane-modified portion significantly improves the adhesion or adhesion to various glass plates for liquid crystal cells, and at the same time has a sizing effect for liquid crystal molecules. It should be improved at the same time.

As described above, according to the present invention, the diaminosiloxane structure derived from the diaminosiloxane compound can be directly introduced into the polymer chain. Adhesion can be improved without forming a polyimide film and performing surface treatment to maintain adhesive strength.

Examples of the tin compound having at least one of a hydrolyzable functional group and an oxidatively decomposable functional group to be added to the polyimide solution include the following general formula (E) (margin) (E) -- An example is an organic tin compound represented by -RA Sn Rec.

Specific examples of the organotin compound represented by the above general formula (E) are as follows.

Tetramethyltin, tetraethyltin, tetrapropyltin,
Tetrabutyltin, tetraoctyltin, tetraphenyltin, tetramethoxytin, tetraethoxytin, tetrabutoxytin, methyltrichlortin, dimethyldichlortin, trimethylchlortin, methoxytrichlortin, dimethoxydichlortin, trimethoxychlortin, ethoxy Examples include trichlortin, jetoxydichlortin, triethoxychlortin, silver octenoate, and silver naphthenate. These can be used alone or in combination of two or more as necessary.

It is important to add these tin compounds to the polyimide solution obtained by the reaction of organic tetracarboxylic acids and diamino compounds. That is, if the tin compound is added at a stage before the synthesis of the polyimide product, it will cause the inconvenience of reaction polymerization itself.

The above polyimide solution is a solution of polyamic acid obtained by reacting an organic tetracarboxylic acid with a diamino compound, or a solution of polyimide obtained by dehydrating and ring-closing imidization of this, and when a tin compound is blended with the polyamic acid solution. After coating it on a substrate, it is heated in the coexistence of oxygen to form a polyimide alignment film, and the water produced as a by-product converts the tin compound into hydroxide, and further heating after cooling converts the hydroxide into tin oxide. As a result, extremely fine tin oxide particles form a polyimide alignment film (
It becomes dispersed in the liquid crystal alignment film). This tin oxide is so fine that it cannot be easily recognized even with a scanning microscope.

In addition, when adding a tin compound to a polyimide solution whose synthesis has progressed to polyimide, the tin compound is oxidized by heating the polyimide solution to form a liquid crystal alignment film in an oxygen atmosphere. , as described above, fine tin oxides become dispersed in the liquid crystal alignment film.

By uniformly dispersing extremely fine tin oxides in the liquid crystal alignment film in this way, the volume resistivity of the liquid crystal alignment film is significantly reduced, and the voltage applied to the electrodes is not significantly attenuated by the liquid crystal alignment film. The current is applied to the liquid crystal, which solves the problem of blurring and inability to display at the edges of large liquid crystal cells, and at the same time improves response speed, which is a feature of this invention. be.

The amount of the tin compound to be used is from o, oooos weight % (hereinafter abbreviated as "%") to 3.
It is preferable to set the content to 0%, and more preferably within the range of 0.05% to 2.5%.

If the amount of the tin compound used is less than 0.0005%, the volume resistivity of the resulting liquid crystal alignment film will be so low that the voltage directly applied to the liquid crystal will be attenuated, potentially resulting in poor alignment. On the other hand, if it exceeds 3.0%, the volume resistivity of the liquid crystal alignment film becomes equal to or lower than that of the liquid crystal itself, which is disadvantageous and increases the leakage current between the liquid crystal and the substrate. Like 0.00
It is desirable to set it to 0.05% to 3.0%.

The liquid crystal sandwiching substrate according to the present invention can be manufactured, for example, as follows. First, an organic tetracarboxylic acid, a diamino compound, and a diaminosiloxane compound are reacted in the above-mentioned organic solvent. This reaction usually proceeds exothermically, but while cooling the reaction vessel using a water bath etc.
Control the temperature below 0°C until the reaction system becomes uniform and transparent.
Just continue. If necessary, heating may be performed at a temperature of 30 to 50° C. within a range that does not impair the transparency of the system. In this case, the amount of the diaminosiloxane compound used is preferably set to 01 to 20 mol% of the total amount of acids and diamino compounds used in the synthesis of the polyamide solution, and more preferably 0゜1
~10 mol%. In this invention, even if a small amount of the diaminosiloxane compound is used as described above, a sufficient effect of improving adhesion to glass etc. can be obtained. On the other hand, if the amount exceeds the above, the film properties (tensile strength and toughness when formed) of the polyimide film that is finally formed tend to be poor, which is not preferable.

Polymerization is carried out in this manner and a reaction product is obtained.

This degree of polymerization can be easily detected by examining the intrinsic viscosity [η] of the reaction product.

The above-mentioned intrinsic viscosity is calculated by the following formula, and the falling time in the formula is measured by a capillary viscometer.

j2n(t,/10) Intrinsic viscosity ηinh −□ It is known that this logarithmic viscosity is directly related to the molecular weight of the polymer.

The polyimide solution used in this invention generally has an intrinsic viscosity of 0.4 to 4.0, preferably 0.5 to 2.0.

Formation of a liquid crystal alignment film using the tin compound-containing polyimide solution obtained as described above can be performed as follows. That is, a 1 to 15% solution of the above tin compound-containing polyimide solution is applied to the electrode formation surface of a substrate (glass plate, etc.) on which an electrode is formed, and 1 to 15% solution of the above tin compound-containing polyimide solution is applied in the presence of oxygen.
0.1-3 hours at 50-350℃, preferably 200-350℃
300°C for 0.5 hour to cause decomposition or oxidation of the tin compound, forming a gold-tin polyimide silane film with a thickness of 500 to 200 mm, and then rubbing the surface of the formed gold-tin polyimide silane film. It can be manufactured by A liquid crystal sandwiching substrate having a polyimide liquid crystal alignment film manufactured in this way is shown in FIG. In the figure, 1 is a glass substrate, 2 is a transparent electrode, and 3 is a polyimide alignment film.

The two liquid crystal sandwiching substrates are placed facing each other with a spacer interposed between them, and sealed with epoxy resin to form a cell. Liquid crystal is injected into this cell, and the injection port is sealed with epoxy resin to form a liquid crystal cell. be able to. This liquid crystal cell is shown in FIG. In the figure, 1 is a glass substrate, 2 is a transparent electrode, 3 is a polyimide alignment film, 4 is a sealing material, and 5 is a Schiff type, biphenyl type, cyclohexane type, ester type, etc. liquid crystal composition.

The above-mentioned liquid crystal cell obtained using the liquid crystal sandwiching substrate of the present invention has excellent orientation of liquid crystal molecules, good translucency, and stability over time, maintains initial high performance for a long period of time, and Since the volume resistivity of the alignment film is extremely low, the voltage applied to the electrodes reaches the liquid crystal without being significantly attenuated by the liquid crystal alignment film. Therefore, even if the liquid crystal cell is made larger, the display will not become partially unclear or impossible, and the response speed will be excellent.

〔Effect of the invention〕

Since the liquid crystal sandwiching substrate of the present invention is manufactured as described above, the adhesiveness of the liquid crystal alignment film is good and stable over time, and the initial high performance can be maintained for a long period of time. In addition, fine particles of tin oxide are dispersed in the liquid crystal alignment film, which reduces the volume resistance value, so even when a large liquid crystal cell is made, the display may be partially unclear. There is no possibility that the system will become disabled, and the response speed can be significantly improved.

Next, examples of the present invention will be described together with comparative examples.

[Example 1] 5 equipped with a stirring device, a cooling tube, a temperature needle, and a nitrogen purge device
A 00 ml t flask was fixed on a water bath. next,
In this flask, N-methyl-2-pyrrolidone 2 was dried overnight on a molecular sieve and further dried under reduced pressure.
81.3 g was added into the above flask and flushed with nitrogen. Then, in the above flask, 19.0 g (0,095 mol) of 4.4°-diaminodiphenyl ether,
Furthermore, 1.24 g (0,005 mol) of a diaminosiloxane compound represented by the following formula was added and stirred to completely dissolve it, and further 3,3'',4,4''-biphenyltetracarboxylic dianhydride 29 .4 g (0.1 mol) was added and stirred until the reaction system became a clear viscous solution. At this time, in order to suppress the rise in temperature, the temperature was controlled to be 30° C. or less using a water bath.

The polyimide solution (polyamic acid solution) thus obtained contains SnO, calculated as 0°001%, in the resin.
0.91 μ of jetoxydichlorotin was added to contain the mixture and stirring was continued for a further 1 hour at room temperature.

Next, this tin-containing polyimide solution was cast onto a metal plate to a dry thickness of 30 μm, and then heated in a hot air dryer at 150°C for 1 hour, then at 200°C for 1 hour, and then at 250°C for 1 hour. A polyimide film was formed by heat treatment in the coexistence of the two.

The passed polyimide film formed was strong and had a volume resistivity of 3×10”9 at room temperature.

On the other hand, the above tin-containing polyimide solution was mixed with N-methyl-2-
It was diluted with a pyrrolidone solution to obtain a diluted solution with a nonvolatile content of 4.7% by weight. This diluted solution was applied to transparent electrodes (1 set width, 100 mm length) equipped with terminal extraction parts.
Using a spinner, use a spinner on the electrode forming surface of the glass plate (A) with a transparent electrode (indium tin oxide) and the glass plate (B) with a transparent electrode processed into a length of 1 crane width and 10 m length with a 5-stitch interval, which is equipped with a terminal extraction part. It was applied evenly over the entire surface.

Then 1 hour at 150°C followed by 1 hour at <200°C.
Further, heat treatment was performed at 250℃ for 1 hour to obtain a thickness of 1.
A liquid crystal sandwiching substrate having a gold-tin-polyimide-silane film of 0.000000000000 was obtained.

The surface of the silane film of the obtained substrate was rubbed in a certain direction using gauze, but no peeling occurred in the silane film.

Further, two rubbed liquid crystal sandwiching substrates were sealed with epoxy resin (cured at 120° C. for 1 hour) via a 5 μm spacer to produce a cell. Liquid crystal was injected into the obtained cell, and the injection port was sealed with epoxy resin to produce a liquid crystal cell. Then, the glass plate (A
) and glass (B), uniform alignment of liquid crystals was observed at all points where the transparent electrodes of glass plate (A) and glass (B) intersected. Furthermore, when the alignment performance of the liquid crystal was measured, the rising speed of the liquid crystal was 1111 msec, which was quite fast.

[Example 2] Instead of 4.4′-diaminodiphenyl ether, 4
．． The same number of moles (37°43 g, 0.095 mol) of 4'-di(P-aminophenoxy)diphenylpropane was used. A polyimide solution (polyamic acid solution) was obtained in the same manner as in Example 1 except for the above.

To the polyimide solution thus obtained, 2.024 g of tetraethoxytin was added so that the resin contained 1.5% in terms of SnO□, and the stirring was further continued at 30°C.
It lasted for 3 hours.

Next, this tin-containing polyimide solution was cast onto a metal plate to a dry thickness of 30 μm, and then heated in a hot air dryer at 150°C for 1 hour, and then at 200°C for 1 hour.
A heat treatment was further performed at 250° C. for 1 hour to form a polyimide film.

The passed polyimide film formed was strong and had a volume resistivity of 4×10”ΩG at room temperature.

On the other hand, the tin-containing polyimide solution was mixed with N-methyl-2
A liquid crystal sandwiching substrate was obtained in exactly the same manner as in Example 1 except that a diluted solution with a nonvolatile content of 5% by weight was prepared using - and lolidon. As in Example 1, the silane film of this substrate did not peel off due to the rubbing treatment. Further, a large liquid crystal cell was produced using this substrate in the same manner as in Example 1, and a voltage of 2.5 V was applied to the terminals.

As a result, uniform alignment of liquid crystals was observed. Furthermore, when the alignment performance of the liquid crystal was measured, the rising speed of the liquid crystal was 151 msec, which was quite fast.

[Example 3] 38.88 g (0.09 mol) of 4.4'-di(P-aminophenoxy)diphenylsulfone was used as the diamino compound, and 2.76 g (0.0 mol) of the following diaminosiloxane compound was used.
1 mol) was used, and 21.8 g (0.1 mol) of pyromellitic dianhydride was used as an acid. Other than that, the reaction was carried out in the same manner as in Example 1 to obtain a polyimide solution.

Next, 5n0 was added to the polyimide solution in the resin.
A tin-containing polyimide solution was obtained in the same manner as in Example 1 by adding 0.667 g of jetoxychlortin so that the content was 0.5% in terms of 2%. Then, this solution was coated with a polyimide film in the same manner as in Example 1, and the volume resistivity was measured, and it was found to be 5 x 10''Ω.

On the other hand, a liquid crystal sandwiching substrate was obtained in the same manner as in Example 1 using the tin-containing polyimide solution. This substrate is Example 1
Similarly, no peeling occurred in the polyimide film due to the rubbing treatment. Further, a large liquid crystal cell was produced using this substrate in the same manner as in Example 1, and a voltage of 2.5 V was applied to the terminals.

As a result, uniform alignment of liquid crystals was observed. Furthermore, when the alignment performance of the liquid crystal was measured, the rising speed of the liquid crystal was 12 msec, which was quite fast.

[Example 4] A polyimide solution was obtained in the same manner as in Example 3, except that 32.2 g (0.1 mol) of benzophenone tetracarboxylic dianhydride was used in place of pyromellitic dianhydride.

Next, SnO was added to the polyimide solution in the resin.
0.685 g of jetoxychlortin was added so that the content was 0.5% in terms of □, and stirring was continued at room temperature for 2 hours.

Next, using this tin-containing polyimide solution, Example 1
A metal-attached film with a thickness of 30 μm was prepared in the same manner as above. The volume resistance value of this film is 2X10”Ω (up to)
Met.

On the other hand, the above tin-containing polyimide solution was mixed with N-methyl-2-
A liquid crystal sandwiching substrate was obtained in the same manner as in Example 1 using this diluted with Lolidon. In this substrate, as in Example 1, no peeling occurred in the polyimide film due to the rubbing treatment. Further, a large liquid crystal cell was produced using this substrate in the same manner as in Example 1, and a voltage of 2.5 V was applied to the terminals.

As a result, uniform alignment of liquid crystals was observed. Furthermore, when the alignment performance of the liquid crystal was measured, the rising speed of the liquid crystal was 13 seconds, which was quite fast.

[Comparative example]

Using the same raw materials as in Example 1, a polymerization reaction was carried out in the same manner as in Example 1 to obtain a polyimide solution. Without adding a tin compound to this polyimide-based solution, it was heated as it was at 120°C for 30 minutes at 200°C.
A polyimide film was formed by heat treatment at ℃ for 1 hour and 250℃ for 1 hour, and its volume resistivity was measured.
The mark was 10"Ω.

On the other hand, a liquid crystal sandwiching substrate was obtained in the same manner as in Example 1 using the polyimide solution containing no tin compound. A large liquid crystal cell was prepared using this substrate in the same manner as in Example 1, and a voltage of 2.5 μm was applied to the terminals.

As a result, alignment of the liquid crystal was observed at the electrode intersection near the terminal extraction electrode, but the degree of alignment became weaker as the distance from the terminal extraction electrode increased (no alignment was observed at the farthest point. When raised,
Although orientation was now recognized even at the farthest point, the contrast was different from other parts, and good results could not be obtained. Further, when the alignment performance of the liquid crystal was measured, the rising speed of the liquid crystal was 13 seconds.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a liquid crystal cell to which the polyimide solution of the present invention is applied, and FIG. 2 is a sectional view of parts used therein. 1-Glass plate 2-Electrode 3-Polyimide film 5-Liquid crystal Figure 2 Procedural Amendment (Spontaneous May 13, 1985 1゜Indication of Incident 1986 Taiou Sosamo 119607 No. 2, Name of Invention I-tan manufacturing method 3, relationship with the person making the amendment Special fraud applicant address Garetsu Maki ml [1-1-2 name name (396) Nitto Electric Industry Co., Ltd. (Kasha Kamai Goro 5, Specification subject to amendment 6, Contents of amendment (1) In the 4th line from the bottom of Specification 16, "hexamethylphosphoramide, etc." is corrected to "hexamethylphosphoramide, etc.". 7. Attachment document inventory

Claims (1)

[Claims] (1) When reacting organic tetracarboxylic acids with a diamino compound whose main component is a compound represented by the following general formula (A), a part of the above diamino compound is reacted with the following general formula (B) prior to the reaction. ) and reacting this diaminosiloxane compound and the remaining diamino compound with the organic tetracarboxylic acids in an organic solvent to prepare a polyimide solution, and to this polyimide solution, A tin compound having at least one of a hydrolyzable functional group and an oxidatively decomposable functional group is blended, and a polyimide solution containing this tin compound is used as a solution for forming a liquid crystal alignment film to produce a liquid crystal sandwiching substrate. A method for manufacturing a liquid crystal sandwiching substrate. (A)...▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, X is O, C=O, CH_2, S, SO_2, ▲
There are mathematical formulas, chemical formulas, tables, etc. ▼-R_1-A-R_1
(However, A is ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and R_1 and R_x are O, S, SO_2, CONH, COO, C
O, CH_2, C(CH_3)_2 or C(CF_3
)_2, which may be the same or different. ). Note that hydrogen in the aromatic ring (including the aromatic ring in A above) may be substituted with a halogen element, an alkyl group, or an aryl group. ](B)…▲Mathematical formula, chemical formula,
There are tables, etc. ▼ [In the formula, R_2 is a divalent aliphatic hydrocarbon group having 1 to 4 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms,
R_3 and R_4 are a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms, and n is an integer of 1 to 5. However, R_3
and R_4 may be the same or different. ]