JP2001072770A - Diaminobenzene derivative, and polyimide and liquid crystal alignment film prepared by using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily obtain a polyimide which is useful for forming a liquid crystal alignment film excellent in alignment uniformity by using a specific alkylated diaminobenzene derivative. SOLUTION: This diaminobenzene derivative is represented by the formula, wherein X and P are each independently a single bond or a divalent organic group selected from among -O-, -COO-, -OCO-, -CONH- and -NHCO-; Q is 1-22C linear alkyl or linear fluoroalkyl; a is an integer of 1-4; R is fluorine, methyl or trifluoromethyl; and b is an integer of 0-4, indicating the number of substituents. A diamine component containing at least 1 mol% diaminobezene derivative of the formula is reacted with at least one compound selected from among tetracarboxylic dianhydrides and their derivatives to give a polymide precursor, which is cyclized to produce a polyimide. The tetracarboxylic dianhydride is preferably an alicyclic tetracarboxylic dianhydride.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel diaminobenzene derivative, a polyimide synthesized using the compound as a raw material, and a liquid crystal alignment film containing the polyimide. The present invention relates to a diamine having a specific structure which is easy to manufacture, a polyimide using the same, and a liquid crystal alignment film. The polyimide synthesized using the diamine of the present invention is particularly useful for use as an alignment film of a liquid crystal display device.

[0002]

2. Description of the Related Art Conventionally, polyimide has been widely used as a protective material and an insulating material in the electric and electronic fields due to its high mechanical strength, heat resistance and solvent resistance. However, the development of the electric and electronic fields in recent years has been remarkable, and correspondingly, materials used have been required to have increasingly higher characteristics. Above all, polyimides have been used exclusively for alignment film applications of liquid crystal display devices because of the uniformity and durability of the coating film surface. However, as the density and performance of liquid crystal displays have been increased, the surface characteristics of polyimide coating films have been emphasized, and it has become necessary to provide new characteristics that are not present in conventional polyimides.

A liquid crystal display element is a display element utilizing electro-optical change of a liquid crystal, and has attracted attention for its characteristics such as small size and light weight and low power consumption, and has recently been used as a display device for various displays. Has achieved remarkable development. Above all, using nematic liquid crystal having positive dielectric anisotropy, liquid crystal molecules are arranged parallel to the substrate at each interface of a pair of electrode substrates facing each other, and the orientation directions of the liquid crystal molecules are orthogonal to each other. A twisted nematic (TN type) field effect type liquid crystal display element combining both substrates is a typical example thereof.

In such a TN-type liquid crystal display device, the major axis direction of the liquid crystal molecules is aligned uniformly and parallel to the surface of the substrate, and the liquid crystal molecules are tilted with respect to the substrate at a fixed tilt angle (hereinafter referred to as tilt). Is important. As a typical method for aligning liquid crystal molecules in this manner, two methods have been conventionally known.

The first method is a method in which an inorganic substance such as silicon oxide is obliquely deposited on a substrate to form an inorganic film on the substrate, and liquid crystal molecules are aligned in a deposition direction.
In this method, a stable orientation having a certain tilt angle can be obtained, but it is not industrially efficient.

The second method is a method in which an organic film is formed on the surface of a substrate, the surface is rubbed in a certain direction with a cloth such as cotton, nylon or polyester, and liquid crystal molecules are aligned in the rubbing direction. In this method, a stable orientation can be obtained relatively easily, and therefore, this method is exclusively used industrially. Examples of the organic film include polyvinyl alcohol, polyoxyethylene, polyamide, and polyimide. Among them, polyimide is most commonly used in terms of chemical stability, thermal stability, and the like.

[0007]

In the field of liquid crystal alignment films, it has been conventionally difficult to stably obtain a high tilt angle by a method of rubbing an organic film such as polyimide. As means for solving this, Japanese Patent Application Laid-Open No. Sho 62-2978
No. 19 proposes a liquid crystal alignment treatment agent comprising a mixture of a long-chain alkyl compound and a polyimide precursor.
Furthermore, Japanese Patent Application Laid-Open No. 64-25126 proposes a liquid crystal aligning agent composed of polyimide using a diamine having an alkyl group as a raw material. As described above, many attempts have been made to increase the tilt angle of the liquid crystal by introducing an alkyl group into polyimide, and it has become possible to increase the tilt angle.

In recent years, the development of TN display elements has been remarkable, and a liquid crystal alignment film has been required to have many characteristics which have never been seen before. Among them, in particular, compatibility between stabilization of the tilt angle and improvement of the uniformity of the alignment is becoming increasingly important from the viewpoint of improving the essential characteristics of the liquid crystal alignment film.

As is apparent from JP-A-64-25126, the conventionally known and exclusively used alkyl diamines are characterized by connecting an alkyl group to a phenylenediamine structure. However,
Using a conventionally known alkyl group-containing diamine,
When synthesizing a polyimide, the alkyl group acts as a steric hindrance, resulting in a problem that the reactivity becomes low and the polymerization takes time, and in some cases, the polymerization hardly proceeds. It takes a long time to carry out the polymerization in terms of industrial production, and low polymerization reactivity has a problem in terms of the durability of the polyimide as an alignment film. Also, of course, such low reactivity,
When copolymerized with another diamine, it appears as a difference in reaction rate. The resulting polyimide is not necessarily uniform from the viewpoint of the uniformity of the repeating units, and as a result, when the liquid crystal alignment film is obtained, a desired tilt angle is obtained, but it is not necessarily satisfactory from the viewpoint of the uniformity of liquid crystal alignment. Was not.

These problems are extremely important for further improving the characteristics of a high-quality, high-definition liquid crystal display device represented by a TN device in the future. That is, there has been a strong demand for an alkyldiamine having excellent reactivity, a polyimide containing the same as a constituent element, and a polyimide liquid crystal alignment film contributing to this point.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances. The present inventors have conducted detailed and systematic studies in order to achieve the object, and as a result, have completed the present invention.

That is, the present invention provides a compound represented by the general formula [1]:

[0013]

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(Wherein X and P are each independently a single bond or —O—, —COO—, —OCO—, —CONH
-, A divalent organic group selected from -NHCO-
Represents a linear alkyl group having 1 to 22 carbon atoms or a linear fluorine-containing alkyl group, a represents the number of substituents as an integer of 1 to 4, R is a fluorine, a methyl group and a trifluoromethyl group B is an integer of 0 to 4 and represents the number of substituents. )).

Further, the present invention relates to a diamine containing at least 1 mol% of the diaminobenzene derivative represented by the above general formula [1], and at least one compound selected from tetracarboxylic dianhydride and its derivative. React
Reduced viscosity of 0.05 to 5.0 dl / g (N-
A polyimide precursor having a concentration of 0.5 g / dl) in methylpyrrolidone, which is obtained by ring-closing a polyimide precursor, represented by the general formula [2]:

[0016]

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(In the formula, A represents a tetravalent organic group constituting a tetracarboxylic acid, and B represents a divalent organic group constituting a diamine.) is there.

Further, the present invention relates to a liquid crystal alignment film containing the above polyimide. Hereinafter, the present invention will be described in detail.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The diaminobenzene derivative of the present invention is easy to synthesize and is useful as a raw material for polyimide, polyamide and the like. Further, by using this as one of the raw materials, a polyimide having an alkyl group or a fluoroalkyl group in a side chain can be obtained. This polyimide is useful as an insulating film for semiconductors, a heat-resistant protective film for optical elements, and the like, but is particularly useful for an alignment film of a liquid crystal display element. It is easily provided and has characteristics such as good liquid crystal orientation.

In particular, the present invention is to obtain a polyimide having a desired repeating unit quickly by using a specific diaminobenzene derivative having an alkyl group. It is also a major object to use a specific polyimide obtained from this diamine as a liquid crystal alignment film to provide a tilt angle to liquid crystal and achieve high uniformity of alignment.

For this purpose, Q in the general formula [1] is a linear alkyl group or a fluoroalkyl group having 1 to 22 carbon atoms, which is essential for controlling the magnitude of the tilt angle. It is connected to the polyimide main chain via the connection part P. X is essential for linking a p-aminophenyl group. R is necessary for controlling the surface properties of the polyimide within a range that does not impair the nucleophilicity of the amino group in consideration of the polymerization reactivity with tetracarboxylic dianhydride and its derivative.

General formula [1]

[0023]

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(Wherein X and P are each independently a single bond or —O—, —COO—, —OCO—, —CONH
-, A divalent organic group selected from -NHCO-
Represents a linear alkyl group having 1 to 22 carbon atoms or a linear fluorine-containing alkyl group, a represents the number of substituents as an integer of 1 to 4, R is a fluorine, a methyl group and a trifluoromethyl group B is an integer of 0 to 4 and represents the number of substituents. The diaminobenzene derivative represented by the formula (2) is a diamine having a specific structure.

[0025]

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(In the formula, R and b are the same as those in the formula [1].) It is composed of the following alkyl or fluorinated alkylbenzene via a connecting part X.

[0027]

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(In the formula, P, Q and a are the same as those in the formula [1].) The synthesis method is not particularly limited. For example, it can be synthesized by the following method.

That is, in the synthesis of the diamine, the corresponding general formula [3] is used.

[0030]

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(Where X, P, Q, a and b are represented by the formula [1]
Is the same as In general, a dinitro compound is synthesized, and the nitro group is reduced to an amino group by an ordinary method.

A and b each independently represent the number of substituents, and a is selected from an integer of 1 to 4, preferably 1 or 2 in consideration of the surface properties, and b is similarly 0 to 2
Selected from the integers

The connecting parts X and P are each independently a bond such as a single bond, an ether bond —O—, an ester bond —COO—, a reverse ester bond —OCO—, an amide bond —CONH—, and a reverse amide bond —NHCO—. And an ether bond, an ester bond, and an amide bond are particularly preferable from the viewpoint of polymerization reactivity. These linking groups can be formed by ordinary organic synthetic techniques. For example, in the case of an ether bond, a corresponding halogen derivative is reacted with a hydroxyl-substituted derivative in the presence of an alkali, and in the case of an amide bond, a corresponding acid chloride is reacted with an amino-substituted derivative in the presence of an alkali. In addition, there are various methods for a single bond, and it is possible to appropriately connect them by using a general organic synthesis technique such as a Grignard reaction, a Friedel-Crafts acylation method of an aromatic ring, a Kishner reduction method, and a cross coupling method. is there.

As a specific example of the raw material for forming the dinitro moiety, the substituent for forming the bond X is, for example, disubstituted with a halogen atom, a hydroxyl group, an amino group, a carboxyl group, a halogenated acyl group or a carbonyl group. Benzene containing the substituted substituent Q and the linking group P. By linking these with a substituted p-nitrobenzene derivative, a desired dinitro compound can be obtained.

Specific examples of the disubstituted benzene derivative are as follows:
Examples include 3,5-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid chloride, 3,5-dicarboxyphenol, 3,5-diaminobenzoic acid, and 3,5-diaminophenol. Also p-
Nitrobenzene derivatives include p-nitrofluorobenzene, p-nitrochlorobenzene, p-nitrobromobenzene, p-nitroiodobenzene, p-nitrophenol, and p-nitrophenol.
Nitrobenzoic acid, p-nitrobenzoic acid chloride, 2-methyl
-4-nitrophenol, 2-trifluoromethyl-4-nitrophenol, 2-methyl-4-nitrobenzoic acid, 2-methyl-4-
Examples include nitrobenzoic acid chloride, 2-trifluoromethyl-4-nitrobenzoic acid, 2-trifluoromethyl-4-nitrobenzoic acid chloride, and acetanilide. These combinations are appropriately selected depending on the purpose in view of availability of raw materials and reactivity. Needless to say, what is shown here is only an example.

The chain substituent Q in the general formula [1] is a linear alkyl group having 1 to 22 carbon atoms or a linear fluorine-containing alkyl group. The number of carbon atoms can be appropriately selected in order to obtain a desired tilt angle when the corresponding polyimide is used as the alignment film.

The diaminobenzene derivative of the present invention represented by the above general formula [1] obtained by the above-mentioned production method can be used as a tetracarboxylic acid dianhydride, tetracarboxylic dihalide, tetracarboxylic acid or other tetracarboxylic acid. By performing polycondensation with an acid dianhydride and a derivative thereof, a polyimide having a specific structure in a side chain can be synthesized.

The method for obtaining the polyimide of the present invention is not particularly limited. Specifically, at least one compound selected from tetracarboxylic dianhydride and derivatives thereof and the diamine are reacted and polymerized to form a polyimide precursor,
It can be obtained by ring-closing imidization.

The tetracarboxylic dianhydride and its derivative used for obtaining the polyimide of the present invention are not particularly limited.

Specific examples thereof include pyromellitic acid 2
Anhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,
4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-
Anthracenetetracarboxylic dianhydride, 1,2,5,6-anthracenetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,3,3', 4 -Biphenyltetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 3,3'4,4'-benzophenonetetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ) Sulfone dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 1,1,1,3,3, 3-hexafluoro-2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) dimethylsilane dianhydride, bis (3,4-dicarboxyphenyl) Diphenylsilane dianhydride, 2,3,4,5-pyridinetetracarboxylic dianhydride, 2,6-bis (3,4-dicarboxyphenyl) Aromatic tetracarboxylic acid 2 such as pyridine 2 anhydride
Anhydrides, their tetracarboxylic acids, their dicarboxylic diacid halides, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride , 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1- Alicyclic tetracarboxylic dianhydrides such as naphthalene succinic dianhydride and their tetracarboxylic acids and their dicarboxylic diacid halides, 1,2,3,
Examples thereof include aliphatic tetracarboxylic dianhydrides such as 4-butanetetracarboxylic dianhydride, tetracarboxylic acids thereof, and dicarboxylic diacid halides thereof.

In particular, for use as a liquid crystal alignment film, alicyclic tetracarboxylic dianhydrides, these tetracarboxylic acids, and dicarboxylic acid diacid halides thereof are preferable from the viewpoint of the transparency of the coating film. 2,3,4-cyclobutanetetracarboxylic dianhydride, 3,4-dicarboxy-1,2,3,4-
Tetrahydro-1-naphthalene succinic dianhydride, bicyclo [3,3,0] -octane-tetracarnbonic dianhydride, 3,5,6-tricarboxynorbornane-2: 3,5: 62 anhydride preferable. Further, one or more of these tetracarboxylic dianhydrides and derivatives thereof may be used in combination.

The present invention relates to tetracarboxylic dianhydrides and derivatives thereof, diaminobenzene derivatives represented by the general formula [1] (hereinafter abbreviated as diamines [1]) and other general diamines (hereinafter generally referred to as general diamines). (Abbreviated as diamine) can also be copolymerized.

The general diamine used at this time is a primary diamine generally used in the synthesis of polyimide, and is not particularly limited. If you dare give specific examples, p-phenylenediamine, m-phenylenediamine, 2,
5-diaminotoluene, 2,6-diaminotoluene, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl,
Diaminodiphenylmethane, diaminodiphenylether, 2,2'-diaminodiphenylpropane, bis (3,5-diethyl-4-aminophenyl) methane, diaminodiphenylsulfone, diaminobenzophenone, diaminonaphthalene, 1,4-bis (4- Aminophenoxy) benzene, 1,4-bis (4-aminophenyl) benzene, 9,10-bis (4-aminophenyl) anthracene, 1,3-bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) diphenyl sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] aromatic diamine such as hexafluoropropane, bis (4-aminocyclohexyl) methane, bis (4-amino-3-methylcyclohexyl) methane Cycloaliphatic diamine and tetramethylene diamine, aliphatic diamines such as hexamethylenediamine, and further,

[0044]

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(Wherein m represents an integer of 1 to 10). Further, one or more of these diamines can be used in combination.

When the polyimide of the present invention is polymerized, the surface properties of the polyimide such as water repellency can be modified by adjusting the ratio of the number of moles of diamine [1] to the total number of moles of diamine used. When used as a liquid crystal alignment film, it is possible to increase wettability with the liquid crystal and further increase the tilt angle of the liquid crystal. At this time, the ratio of the number of moles of the diamine [1] to the total number of moles of the diamine used is at least 1 mol%.

When used as a liquid crystal alignment film, it is easy to obtain a polyimide having an appropriate degree of polymerization in practical use, or the tilt angle required in a general liquid crystal display system (for example, a twisted nematic system) is several degrees. ~ 1
The ratio of the number of moles of the diamine [1] to the total number of moles of the diamine to be used depends on the number of alkyls of Q, but the range of 1 to 100% by mole is from the viewpoint that about 0 degrees is frequently used. In general, In the case of the vertical alignment method, the ratio of the number of moles of the diamine [1] is 40 mol%
Generally, it is 100 mol%.

After reacting and polymerizing tetracarboxylic dianhydride and its derivative with the above diamine to obtain a polyimide precursor, this is subjected to ring-closing imidization. The tetracarboxylic dianhydride and its derivative used in this case are as follows. It is common to use tetracarboxylic dianhydride. The ratio of the number of moles of tetracarboxylic dianhydride to the total number of moles of diamine [1] and general diamine is preferably from 0.8 to 1.2. As in the ordinary polycondensation reaction, the degree of polymerization of the produced polymer increases as the molar ratio approaches 1.

If the degree of polymerization is too small, the strength of the polyimide film becomes insufficient. On the other hand, if the degree of polymerization is too large, the workability during the formation of the polyimide film may be deteriorated. Therefore, the degree of polymerization of the product in this reaction is 0.05 to 5.0 dl / g (at a temperature of 30 ° C.) in terms of reduced viscosity of the polyimide precursor solution.
In N-methylpyrrolidone at a concentration of 0.5 g / dl).

The method of reacting and polymerizing tetracarboxylic dianhydride with the above diamine is not particularly limited, and generally, N-methylpyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, etc. The above-mentioned diamine is dissolved in the organic polar solvent described above, tetracarboxylic dianhydride is added to the solution, and a reaction is performed to synthesize a polyimide precursor, followed by dehydration ring-closing imidization.

The reaction temperature at the time of reacting tetracarboxylic dianhydride with the above diamine to form a polyimide precursor is as follows:
Any temperature between 20 and 150C, preferably between -5 and 100C can be chosen. Further, the polyimide precursor can be dehydrated by heating at 100 to 400 ° C. or chemically imidized by using a commonly used imidization catalyst such as pyridine / acetic anhydride. In this case, the imidization ratio can be arbitrarily controlled between 0 and 100% depending on the reaction conditions. However, when used as an alignment film, the imidization ratio is preferably 60 to 100%.

When the polyimide of the present invention is used as an insulating film and a protective film of an electric / electronic device and an alignment film of a liquid crystal display device, it is necessary to form a polyimide film having a uniform thickness on a substrate.

In order to form the polyimide coating film, usually, a polyimide precursor solution is applied as it is to a substrate, and then imidized on the substrate to form a polyimide coating film. As the polyimide precursor solution used at this time, the above-mentioned polymerization solution may be used as it is, or the produced polyimide precursor is poured into a poor solvent such as a large excess of water or methanol, and the precipitate is recovered. It may be dissolved before use. The solvent for diluting the polyimide precursor solution and / or the solvent for re-dissolving the precipitated and recovered polyimide precursor is not particularly limited as long as it can dissolve the polyimide precursor.

Specific examples of these solvents include N-methylpyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide and the like. These may be used alone or as a mixture. Further, even if the solvent cannot obtain a uniform solution by itself, the solvent may be added and used within a range where a uniform solution can be obtained. Examples include ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol and the like. Further, it is preferable to add an additive such as a coupling agent to the obtained polyimide precursor solution for the purpose of improving the adhesion between the polyimide film and the substrate.

The temperature for imidization on the substrate is 1
Any temperature between 00 and 400 ° C. can be employed,
A range from 0 to 350C is preferred.

On the other hand, when the polyimide of the present invention is dissolved in a solvent, the polyimide precursor obtained by reacting tetracarboxylic dianhydride with the above diamine is imidized in a solution to form a polyimide solution. it can. When a polyimide precursor is converted into polyimide in a solution, a method of dehydrating and cyclizing by heating is usually employed. Any temperature of 150 to 350 ° C, preferably 120 to 250 ° C, can be selected as the ring closing temperature by this heat dehydration.

As another method of converting the polyimide precursor into polyimide, the ring can be chemically closed using a known dehydration ring closing catalyst.

The polyimide solution thus obtained can be used as it is, or it can be used by precipitating and isolating it in a poor solvent such as methanol or ethanol and then re-dissolving it in an appropriate solvent. The solvent to be redissolved is not particularly limited as long as it dissolves the obtained polyimide.Examples thereof include 2-pyrrolidone, N-methylpyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, N,
N-dimethylacetamide, N, N-dimethylformamide,
γ-butyrolactone and the like.

In addition, a solvent which does not dissolve the polyimide alone may be added to the above solvent as long as the solubility is not impaired. Examples include ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol and the like.

For the purpose of further improving the adhesion between the polyimide film and the substrate, it is of course preferable to add an additive such as a coupling agent to the obtained polyimide solution.

This solution is applied to a substrate, and the solvent is evaporated to form a polyimide film on the substrate. The temperature at this time is sufficient if the solvent is evaporated, and usually 80 to 150 ° C. is sufficient.

When used as a liquid crystal alignment film,
A liquid crystal alignment film can be formed by forming a polyimide film having a thickness of 100 to 3,000 angstroms on a transparent substrate such as a glass or plastic film with a transparent electrode, and then subjecting the polyimide film to a rubbing treatment.

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

[0064]

EXAMPLES (Synthesis of diamine) Example 1 Synthesis of (n-dodecyl [3,5-bis (4-aminobenzoylamino)] benzoate) (4)

[0065]

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In a 500 ml flask, 1-dodecanol (6
After adding 5.01 g, 348.9 mmol), triethylamine (44.00 g, 435.0 mmol) and tetrahydrofuran (410 ml) to form a homogeneous solution, 3,5-dinitrobenzoyl chloride (80.16 g, 347.7 mm).
ol) in THF (80 ml) was added dropwise. afterwards,
The mixture was stirred under reflux for 2.5 hours. The reaction solution was poured into water, and the precipitated solid was separated by filtration and recrystallized with acetonitrile.
Colorless crystals were obtained (121.12 g, yield: 82).
%). From the IR and NMR spectra, this crystal was confirmed to be n-dodecyl-3,5-dinitrobenzoate (1). Melting point 64 [deg.] C.

Dioxane (250 ml) was added to n-dodecyl-3,5-dinitrobenzoate (1) (25.13 g, 59.2 mmol).
After adding d-C (1.51 g), the mixture was stirred in a hydrogen atmosphere for 7 hours. After filtering Pd-C, the filtrate was poured into water, and the precipitated crystals were filtered. After drying, recrystallization was performed with n-hexane to obtain pale yellow crystals (18.46 g, yield: 79%). According to IR and NMR spectra, this crystal was n-dodecyl-3,5-diaminobenzoate (2). Melting point 64 [deg.] C.

In a 200 ml flask, n-dodecyl-3,5-diaminobenzoate (2) (8.01 g, 20.3 mm
ol), triethylamine (4.57 g, 45.2 mm)
ol) and tetrahydrofuran (100 ml) to make a homogeneous solution, and then 4-nitrobenzoyl chloride (7.93 g,
(42.8 mmol) in THF (50 ml) was added dropwise. Thereafter, the mixture was stirred under reflux for 6 hours. The reaction solution was poured into water, and the precipitated solid was separated by filtration and recrystallized from acetonitrile to obtain pale yellow crystals (10.15 g, yield: 81%). From the IR and NMR spectra, this crystal was confirmed to be n-dodecyl [3,5-bis (4-nitrobenzoylamino)] benzoate (3). 189 ° C.

N-dodecyl [3,5-bis (4-nitrobenzoylamino)] benzoate (3) (7.99 g, 12.
Dioxane (160 ml) was added to 9 mmol), Pd-C (0.87 g) was added to this solution under a nitrogen atmosphere, and the mixture was stirred for 4 hours in a hydrogen atmosphere. After filtering Pd-C,
The filtrate was poured into water, and the precipitated crystals were filtered. After drying, T
The crystals were recrystallized from HF-n-hexane to give pale yellow crystals (4.2
5 g, yield: 65%). According to IR and NMR spectra, this crystal was found to be the desired n-dodecyl [3,5-bis (4-aminobenzoylamino)] benzoate (4)
(Melting point: 186 ° C.). The analysis results are shown below.

¹ H-NMR (d-DMSO, δ ppm): 9.9 (2H, s), 8.6
(1H, s), 8.1 (2H, s), 7.8 (4H, d), 6.6 (4H, d), 5.8 (4H, s), 4.3
(2H, t), 1.7 (2H, m), 1.2-1.4 (18H, broad), 0.8 (3H, t) .IR
^{(KBr, cm -1): 3445,3387,3351} (NH 2), 3304,3200 (NH), 29
_{55,2922,2853 (CH 2), 1710 (} COO), 1640,1608 (CONH).

Example 2 (Synthesis of n-hexyl [3,5-bis (4-aminobenzoylamino)] benzoate)

[0072]

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3,5-dinitrobenzoyl chloride (74.3)
g, 322.5 mmol) and hexyl alcohol (3
3.0 g (323.6 mmol), and n-hexyl-3,5-dinitrobenzoate was obtained in the same manner as in Example 1 (81.1 g, yield: 85%).

The obtained dinitro compound (33.4 g, 1
12.8 mmol) in the same manner as in Example 1,
Recrystallization gave n-hexyl-3,5-diaminobenzoate (25.6 g, yield: 96%).

Using n-hexyl-3,5-diaminobenzoate (24.0 g, 101.7 mmol) and 4-nitrobenzoyl chloride (39.7 g, 214.4 mmol),
In the same manner as in Example 1, n-hexyl [3,5-bis (4-nitrobenzoylamino)] benzoate was obtained (44.5).
g, yield: 82%).

Finally, the dinitro compound (20.4
g, 38.2 mmol) was reduced and recrystallized in the same manner as in Example 1 to obtain n-hexyl [3,5-bis (4-aminobenzoylamino)] (5) (14.8 g, yield). Rate: 82
%). Melting point 208 [deg.] C. The analysis results are shown below.

Mass (m / e): 474 (M +). ¹ H-NMR (d-DMSO, δ ppm): 9.9 (2H, s), 8.6 (1 H, s), 8.1 (2)
H, s), 7.8 (4H, d), 6.6 (4H, d), 5.8 (4H, s), 4.3 (2H, t), 1.7 (2
H, m), 1.2-1.4 (6H, broad), 0.9 (3H, t). IR (KBr, cm ^-1 ): 3445,3339,3351 (NH ₂ ), 3304,3204 (NH),
_{2955,2931 (CH 2), 1694 (} COO), 1645,1605 (CONH).

Example 3 (Synthesis of n-hexadecyl [3,5-bis (4-aminobenzoylamino)] benzoate (6))

[0079]

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3,5-dinitrobenzoyl chloride (60.6
g, 263.0 mmol) and hexadecyl alcohol (63.9 g, 263.9 mmol).
N-Hexadecyl-3,5-dinitrobenzoate was obtained in the same manner as described above (103.2 g, yield: 90%).

The obtained dinitro compound (40.68 g,
93.3 mmol) in the same manner as in Example 1,
Recrystallization gave n-hexadecyl-3,5-diaminobenzoate (35.0 g, yield: 100%).

Diamine compound (16.7 g, 44.4 m
mol) and 4-nitrobenzoyl chloride (17.3 g, 9
Using 3.6 mmol), n-hexadecyl [3,5-bis (4-nitrobenzoylamino)] benzoate was obtained in the same manner as in Example 1 (25.4 g, yield: 85%).

Finally, the dinitro compound (13.4)
g, 19.9 mmol) was reduced and recrystallized in the same manner as in Example 1 to obtain n-hexadecyl [3,5-bis (4-aminobenzoylamino)] (6) (12.0 g, yield Rate: 9
8%). 139 ° C. The analysis results are shown below.

Mass (m / e): 614 (M +). ¹ H-NMR (d-DMSO, δ ppm): 10.0 (2H, s), 8.6 (1 H, s), 8.1 (2)
H, s), 7.8 (4H, d), 6.6 (4H, d), 5.8 (4H, s), 4.3 (2H, t), 1.7 (2
H, m), 1.2-1.4 (26H, broad), 0.8 (3H, t). IR (KBr, cm ^-1 ): 3388,3346 (NH ₂ ), 3304,3204 (NH), 2952,
2917, 2834 (CH ₂ ), 1708 (COO), 1645, 1609 (CONH).

Example 4 (Synthesis of n-dodecyl [3,5-bis (4-aminophenoxy)] benzoate) (10)

[0086]

Embedded image

In a 500 ml flask, 3,5-dihydroxymethylbenzoate (40.0 g,
238.1 mmol), 4-fluoronitrobenzene (6
7.1 g, 475.8 mmol), potassium carbonate (6
5.4 g) and dimethylacetamide (350 ml) were added, and the mixture was stirred at 90 ° C. for 9 hours. Filtering the reaction solution,
The filtrate was left overnight. The precipitated solid was separated by filtration and recrystallized from ethyl acetate to obtain colorless solid 3,5-bis (4-nitrophenoxy) methylbenzoate (7) (7).
8.5 g, yield: 80%). 183 ° C.

The above dinitro compound (70.
0 g, 170.7 mmol), sulfuric acid (17.5 g) and acetic acid (600 ml), and the mixture was stirred under reflux for 8 hours. The reaction solution was left overnight, and the precipitated solid was separated by filtration. Recrystallization from acetic acid gave colorless crystals of 3,5-bis (4-nitrophenoxy) benzoate (8) (59.3 g, yield:
87%). 230 ° C.

In a 500 ml flask, 3,5-bis (4-nitrophenoxy) benzoate (8) (45.0 g, 11
4.0 mmol, thionyl chloride (250 ml)
The mixture was stirred under reflux for 3 hours. After completion of the reaction, excess thionyl chloride was removed by distillation, and THF (400 ml) was added to the residue. This THF solution was added to n-dodecyl alcohol (23.
5g, 126.3 mmol), triethylamine (1
2.7 g, 125.7 mmol) in a THF solution (100
ml) at 80 ° C. After dropping, 15
The mixture was stirred under reflux for an hour. Concentrate the solvent and add water (1500m
l) and extracted with ethyl acetate. Water layer, 1N
Washed with sodium hydroxide and dried over anhydrous sodium sulfate. The solvent was further distilled off under reduced pressure, and the residue was recrystallized from acetonitrile to obtain n-dodecyl [3,5-bis (4-nitrophenoxy)] benzoate) (9) (47.6 g, yield: 74). %). Melting point 64 [deg.] C.

N-Dodecyl [3,5-bis (4-nitrophenoxy)] benzoate) (9) (15.7 g, 27.8 m)
mol), and Pd-C (1.7 g) was added to this solution under a nitrogen atmosphere, followed by stirring in a hydrogen atmosphere for 6 hours. After filtering Pd-C, the filtrate was poured into water, and the precipitated crystals were filtered. After drying, recrystallization was performed with acetonitrile to obtain pale yellow crystals (9.00).
g, yield: 64%). Melting point 49 [deg.] C. IR, NMR, Ma
The ss spectrum confirmed that the crystals were the desired n-dodecyl [3,5-bis (4-aminobenzoylamino)] benzoate (10). The analysis results are shown below.

Mass (m / e): 504 (M +). ¹ H-NMR (d-DMSO, δ ppm): 7.2 (2H, s), 6.9 (4H, d), 6.7 (1
H, s), 6.6 (4H, d), 4.2 (2H, t), 3.8 (4H, s), 1.6 (2H, m), 1.1-
1.3 (18H, broad), 0.9 (3H, t) IR (KBr, cm -1):. 3459,3374 (NH 2), 3304,3200 (NH), 2959,
_{2917,2847 (CH 2), 1708 (} COO), 1216 (ArO).

Example 5 (Synthesis of n-hexadecyl [3,5-bis (4-aminobenzoylamino)] benzoate (11))

[0093]

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The 3,5-bis (4-nitrophenoxy) benzoate (8) obtained in Example 4 (25.6 g, 64.6)
mmol), n-hexadecyl alcohol (17.3 g,
71.5 mmol) to give n-hexadecyl [3,5-bis (4-nitrophenoxy)] benzoate in the same manner as in Example 4 (32.4 g, yield: 81%).

Finally, the dinitro compound (16.4)
g, 26.5 mmol) was reduced and recrystallized in the same manner as in Example 4 to obtain n-hexadecyl [3,5-bis (4-aminophenoxy)] benzoate (11) (13.5 g,
Yield: 91%). Melting point 54 [deg.] C. The analysis results are shown below.

Mass (m / e): 560 (M +). ¹ H-NMR (d-DMSO, δ ppm): 7.2 (2H, s), 6.8 (4H, d), 6.6 (1
H, s), 6.5 (4H, d), 4.2 (2H, t), 3.8 (4H, s), 1.6 (2H, m), 1.1-
1.4 (26H, broad), 0.9 (3H, t). IR (KBr, cm ^-1 ): 3460,3376 (NH ₂ ), 3302,3200 (NH), 2960,
_{2917,2847 (CH 2), 1708 (} COO), 1216 (ArO).

(Production of polyimide) Example 6 5 g (10.5 mmol) of n-dodecyl [3,5-bis (4-aminobenzoylamino)] benzoate obtained in Example 1 and 1,
2,3,4-cyclobutanetetracarboxylic dianhydride 2.1 g
(10.5 g) was dissolved in 40 g of N-methylpyrrolidone, and stirred at 20 ° C. for 8 hours to perform a polycondensation reaction, thereby preparing a polyimide precursor solution.

The reduced viscosity of the obtained polyimide precursor was 0.80 dl / g (concentration: 0.5 g / dl, in N-methylpyrrolidone at 30 ° C.).

This solution was heat-treated at 180 ° C. for 1 hour to form a uniform polyimide coating film. IR of the obtained coating film
The measurement was performed to confirm that the polyimide had a dodecyl group.

Example 7 5 g (10.5 mmol) of n-dodecyl [3,5-bis (4-aminobenzoylamino)] benzoate obtained in Example 1
l) and 2.6 g (10.5 mmol) of bicyclo [3,3,0] -octane-tetracarmbonic dianhydride are dissolved in 40 g of N-methylpyrrolidone, and the mixture is stirred at 20 ° C. for 8 hours for polycondensation reaction. Was performed to prepare a polyimide precursor solution. The reduced viscosity of the obtained polyimide precursor is 0.70 dl / g.
(Concentration 0.5 g / dl, in N-methylpyrrolidone, 30
° C).

Acetic anhydride and pyridine as imidation catalysts were added to this solution and reacted at 60 ° C. for 1 hour to obtain a soluble polyimide resin solution. This solution was poured into 500 g of methanol, and the obtained precipitate was filtered and dried to obtain a white polyimide powder.

This polyimide resin powder was found to have a
% Imidization was confirmed. In addition, IR measurement of the obtained coating film confirmed that it was a polyimide having a dodecyl group.

Example 8 5 g (10.5 mmol) of n-dodecyl [3,5-bis (4-aminobenzoylamino)] benzoate obtained in Example 1
l) and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic dianhydride 2.9 (10.5 mmol)
It was dissolved in 40 g of N-methylpyrrolidone and stirred at 20 ° C. for 8 hours to carry out a polycondensation reaction to prepare a polyimide precursor solution. The reduced viscosity of the obtained polyimide precursor was 0.75.
dl / g (concentration: 0.5 g / dl, in N-methylpyrrolidone at 30 ° C.).

Acetic anhydride and pyridine were added to this solution as imidation catalysts, and reacted at 60 ° C. for 1 hour to obtain a soluble polyimide resin solution. This solution was poured into 500 g of methanol, and the obtained precipitate was filtered and dried to obtain a white polyimide powder.

This polyimide resin powder was found to have a 90
% Imidization was confirmed. In addition, IR measurement of the obtained coating film confirmed that it was a polyimide having a dodecyl group.

Example 9 5 g (10.5 mmol) of n-dodecyl [3,5-bis (4-aminobenzoylamino)] benzoate obtained in Example 1
l) and 2.6 g (10.5 mmol) of 3,5,6-tricarboxynorbornane-2: 3,5: 62 anhydride are dissolved in 40 g of N-methylpyrrolidone, and the mixture is stirred at 20 ° C. for 8 hours for polycondensation. The reaction was performed to prepare a polyimide precursor solution. The reduced viscosity of the obtained polyimide precursor was 0.55 dl / g (concentration: 0.5 g / dl, in N-methylpyrrolidone, 30 ° C.).

Acetic anhydride and pyridine were added to this solution as imidation catalysts, and reacted at 60 ° C. for 1 hour to obtain a soluble polyimide resin solution. This solution was poured into 500 g of methanol, and the obtained precipitate was filtered and dried to obtain a white polyimide powder.

According to NMR, the polyimide resin powder was 90
% Imidization was confirmed. In addition, IR measurement of the obtained coating film confirmed that it was a polyimide having a dodecyl group.

Examples 10 to 20 Using the diamines synthesized in Examples 2 to 5, Examples 6 to 9
Using the tetracarboxylic dianhydride used in Example 1, a polyimide was synthesized according to each Example, and I was synthesized according to Example 6.
R measurement was performed to confirm that the polyimide was the target polyimide. The reduced viscosity of the polyimide precursor solution (concentration: 0.5 g / dl, in N-methylpyrrolidone, 30
° C).

[0110]

Table 1 Table 1 Example Diamine tetracarbodiacid dianhydride reduced viscosity (dl / g) １０ 10 Example 2 Example 6 1.05 11 Example 2 Example 7 0.82 12 Example 2 Example 8 0.77 13 Example 2 Example 9 0.60 14 Example 3 Example 6 0.74 15 Example 3 Example 7 0.75 16 Example 3 Example 8 0.65 17 Example 3 Example 9 0.53 18 Example 4 Example 6 1.14 19 Example 4 Example 7 0.96 20 Example 4 Example 8 0.88 21 Example 4 Example 9 0.67 22 Example 5 Example 6 1.03 23 Example 5 Example 7 0.89 24 Example 5 Example 8 0.83 25 Example 5 Example 9 0. 0 ──────────────────────────

Comparative Example 1 Using hexadecyloxy-2,4-diaminobenzene as a diamine, 5 g (14.3 mmol) and 1,2,3,4-cyclobutanetetracarboxylic dianhydride 2.8 g (14.3 m
mol) was dissolved in 40 g of N-methylpyrrolidone, and 20
The mixture was stirred at a temperature of 8 ° C. for 8 hours to perform a polycondensation reaction, thereby preparing a polyimide precursor solution. The reduced viscosity of the obtained polyimide precursor was as low as 0.35 dl / g (concentration: 0.5 g / dl, in N-methylpyrrolidone, 30 ° C.).

Comparative Example 2 Using hexadecyloxy-2,4-diaminobenzene as a diamine, 5 g (14.3 mmol) of bicyclo [3,3,
0] -Octane-tetracarnbonic acid dianhydride 3.6 g
(14.3 mmol) was dissolved in 40 g of N-methylpyrrolidone and stirred at 20 ° C. for 4 hours to carry out a polycondensation reaction.
The polymerization hardly proceeded, and only an oligomer was formed. Heating was performed, but no improvement effect was observed.

Comparative Example 3 Using hexadecyloxy-2,4-diaminobenzene as a diamine, 5 g (14.3 mmol) and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid 2 4.3 g (14.3 mmol) of the anhydride was dissolved in 40 g of N-methylpyrrolidone, and the mixture was stirred at 20 ° C. for 4 hours to perform a polycondensation reaction. However, the polymerization hardly proceeded, and only an oligomer was formed. . Heating was performed, but no improvement effect was observed.

Comparative Example 4 Using hexadecyloxy-2,4-diaminobenzene as a diamine, 5 g (14.3 mmol) and 3,5,6-tricarboxynorbornane-2: 3,5: 62 anhydride 3.6 g ( 14．
3 mmol) in 40 g of N-methylpyrrolidone
The polycondensation reaction was performed by stirring at 20 ° C. for 4 hours, but the polymerization hardly proceeded, and only oligomers were formed. Heating was performed, but no improvement effect was observed.

(Manufacture of Liquid Crystal Alignment Film) Examples 26 to 45 Next, the polyimide precursor or the polyimide solution obtained in Examples 6 to 25 was coated on a glass substrate.
A polyimide coating film was formed by heat treatment at ℃, and the alignment uniformity and tilt angle of the liquid crystal when a liquid crystal alignment film was formed by the following method were measured.

Evaluation of tilt angle: The polyimide precursor or the polyimide solution obtained in Examples 6 to 21 and Comparative Example 1 was diluted with N-methylpyrrolidone or γ-butyrolactone to obtain a solution having a resin concentration of 5%. Spin coating at 3500 revolutions / minute on a glass substrate with
For 1 hour at 250 ° C. to form a uniform polyimide coating film. After rubbing this coating film with a cloth, 23 μm
Were assembled with the rubbing direction parallel to each other, and a liquid crystal (ZLI-2003, manufactured by Merck) was injected to prepare homeotropically or homogeneously aligned cells.

After heat-treating the cell at 120 ° C. for 1 hour, the uniformity of the liquid crystal orientation was confirmed under a polarizing microscope, and the tilt angle was measured by a crystal rotation method or a magnetic field capacity method. Table 2 shows the results.

[0118]

Table 2 ２ Example Polyimide diamine Tilt angle Orientation uniformity (Example) (Example) (Example)゜) ────────────────────────── 266 ^* 190 uniform 27 7 190 uniform 28 88 190 uniform 29 99 190 uniform 30 10 ^* 26 uniform 31 11 22 2 uniform 32 12 23 uniform 33 13 23 uniform 34 14 ^* 3 90 uniform 35 15 390 uniform 36 16 3 90 uniform 37 17 390 uniform 38 18 ^* 4 90 uniform 39 194 194 90 uniform 40 20 490 uniform 41 21 4 90 uniform 42 22 ^* 590 uniform 43 235 90 uniform 44 24 590 uniform 45 255 590 uniform comparative example 1 190 non-uniform ───────── ────── * using a polyimide precursor solution.

[0119]

According to the present invention, the diaminobenzene derivative of the present invention is easy to synthesize and has a high reactivity to quickly polymerize irrespective of the structure of the acid dianhydride, so that a corresponding high molecular weight polyimide can be easily obtained. . Further, in the case of polyimide for an alignment film of a liquid crystal display element, the liquid crystal is uniformly aligned, and a desired tilt angle can be easily obtained.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hideyuki Isogai 722-1, Tsuboi-cho, Funabashi-shi, Chiba Nissan Chemical Industry Co., Ltd. Central Research Laboratory (72) Inventor Hideyuki Endo 722-1, Tsuboi-cho, Funabashi-shi, Chiba Nissan Chemical Central Research Laboratory Co., Ltd. (72) Inventor Hiroyoshi Fukuro 722-1, Tsuboi-cho, Funabashi-shi, Chiba Pref. Nissan Chemical Industry Co., Ltd.

Claims (7)

[Claims] 1. A compound of the general formula [1] (Wherein X and P are each independently a single bond or -O
-, -COO-, -OCO-, -CONH-, -NHC
Q is a divalent organic group selected from O-,
Represents a linear alkyl group or a linear fluorine-containing alkyl group of 22, a represents the number of substituents as an integer of 1 to 4,
R is a substituent selected from fluorine, a methyl group and a trifluoromethyl group, and b is an integer of 0 to 4 and represents the number of the substituents. A) a diaminobenzene derivative represented by the formula: 2. A compound of the general formula [1] (Wherein X and P are each independently a single bond or -O
-, -COO-, -OCO-, -CONH-, -NHC
Q is a divalent organic group selected from O-,
22 represents a linear alkyl group or a linear fluorine-containing alkyl group, a represents the number of substituents as an integer of 1 to 4,
R is a substituent selected from fluorine, a methyl group and a trifluoromethyl group, and b is an integer of 0 to 4 and represents the number of the substituents. A) a diamine containing at least 1 mol% of a diaminobenzene derivative represented by formula (1) with at least one compound selected from tetracarboxylic dianhydride and a derivative thereof, and having a reduced viscosity of 0.05 to 5.0 dl / g
(In N-methylpyrrolidone at a temperature of 30 ° C., a concentration of 0.5 g /
dl), which is a polyimide precursor obtained by ring-closing the polyimide precursor, represented by the general formula [2]: (In the formula, A represents a tetravalent organic group constituting a tetracarboxylic acid, and B represents a divalent organic group constituting a diamine.) A polyimide having a repeating unit represented by the following formula: 3. The polyimide according to claim 2, wherein the tetracarboxylic dianhydride is an alicyclic tetracarboxylic dianhydride. 4. An alicyclic tetracarboxylic dianhydride comprising 1,2,
3,4-cyclobutanetetracarboxylic dianhydride, bicyclo [3,3,0] -octane-tetracarboxylic dianhydride, 3,4
-Dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic dianhydride and 3,5,6-tricarboxynorbornane
The polyimide according to claim 3, which is at least one tetracarboxylic dianhydride selected from -2: 3,5: 62 anhydrides. 5. A compound of the general formula [1] (Wherein X and P are each independently a single bond or -O
-, -COO-, -OCO-, -CONH-, -NHC
Q is a divalent organic group selected from O-,
Represents a linear alkyl group or a linear fluorine-containing alkyl group of 22, a represents the number of substituents as an integer of 1 to 4,
R is a substituent selected from fluorine, a methyl group and a trifluoromethyl group, and b is an integer of 0 to 4 and represents the number of the substituents. A) a diamine containing at least 1 mol% of a diaminobenzene derivative represented by formula (1) with at least one compound selected from tetracarboxylic dianhydride and a derivative thereof, and having a reduced viscosity of 0.05 to 5.0 dl / g
(In N-methylpyrrolidone at a temperature of 30 ° C., a concentration of 0.5 g /
dl), which is a polyimide precursor which is ring-closed to obtain a polyimide precursor of the general formula [2]: (In the formula, A represents a tetravalent organic group constituting a tetracarboxylic acid, and B represents a divalent organic group constituting a diamine.) A liquid crystal containing a polyimide having a repeating unit represented by the following formula: Alignment film. 6. The liquid crystal alignment film according to claim 5, wherein the tetracarboxylic dianhydride is an alicyclic tetracarboxylic dianhydride. 7. An alicyclic tetracarboxylic dianhydride comprising 1,2,
3,4-cyclobutanetetracarboxylic dianhydride, bicyclo [3,3,0] -octane-tetracarmbonic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid 7. The liquid crystal alignment film according to claim 6, which is at least one tetracarboxylic dianhydride selected from the group consisting of 3,5,6-tricarboxynorbornane-2: 3,5: 62 anhydride.