KR20050043707A - Novel diamine and polymer obtained by using it as a material - Google Patents

Abstract

The present invention relates to a diamine represented by the following formula (1), a polyamine acid or polyimide prepared from the diamine, an alignment agent containing these polymers, and a liquid crystal display device using the thin film obtained from the alignment agent as an alignment film:

(One)

[Wherein Q is alkylene, A is a single bond or a substituted or unsubstituted 1,4-phenylene and R ¹ , R ² , R ³ and R ⁴ are monovalent groups]

Description

New diamines and polymers based on them {NOVEL DIAMINE AND POLYMER OBTAINED BY USING IT AS A MATERIAL}

The present invention relates to a liquid crystal display device comprising a novel diamine, a polyamine acid or polyimide produced using the diamine, a liquid crystal aligning agent using these polymers, and an alignment film using the aligning agent.

The liquid crystal display device is from Twisted Nematic (TN) to Super Twisted Nematic (STN) according to the needs of display quality or response speed such as screen enlargement or colorization, contrast or color development. In addition, it has evolved into a TFT type display device in which thin film transistors (TFTs) are mounted on individual pixels. In recent years, the driving method of the TFT type display device has been improved. For example, in order to further expand the viewing angle, an in-plane switching (IPS) method or a vertical alignment (VA) method is used. In addition, an optically compensated band (OCB) method having a response speed capable of responding to moving images is being developed.

The alignment film plays two roles in orienting the liquid crystal molecules in a predetermined direction in the display element and inclining the liquid crystal molecules with respect to the substrate plane (giving a free tilt angle). The inclination of the liquid crystal molecules with respect to the substrate plane is called a pretilt angle, which is used later in this specification. In order to minimize the temporal, chemical, and thermal deterioration of molecular alignment over time, a polyimide thin film having a high glass transition point (Tg) and excellent chemical resistance or heat resistance is mainly used as the material. The alignment film is usually coated with a solution of polyamic acid or soluble polyimide (hereinafter also referred to as varnish) to an electrode portion glass substrate by a spinner method or a printing method, and the substrate is heated to polyamine acid. The thin film of polyimide is obtained by dehydration, ring closure, or evaporation of the solvent of the soluble polyimide solution, which is then obtained through an orientation treatment process such as rubbing.

Such an alignment film requires an effect accompanying the liquid crystal display device as follows:

(1) Give an appropriate pretilt angle to liquid crystal molecules. In addition, in the said pretilt angle, the change by the indentation intensity | strength at the time of rubbing, or the temperature at the time of heating should be small.

(2) Orientation processing without an orientation defect of a liquid crystal display element should be possible.

(3) An appropriate voltage holding ratio (VHR) should be provided to the liquid crystal display device.

(4) It is difficult to cause a phenomenon called "burning phenomenon" in which a previous image remains as an afterimage when an arbitrary image is displayed on the liquid crystal display for a long time and then replaced with a separate image.

In particular, the high-quality alignment film used for the TFT display device is required to have a high voltage retention and hardly burn out.

The burning phenomenon is attributable to relaxation of the electric double layer caused by the applied voltage, attributable to the residual charges generated by localization of charged particles such as ions contained in the display element by application of voltage, It is reported that such a thing is due to the low orientation regulation force with respect to a liquid crystal. Particularly, in the display device of the IPS type in which the electric field direction applied to the liquid crystal using the STN method or the comb-shaped electrode having a large torsion angle of the liquid crystal between the opposing substrates is substantially parallel to the substrate interface, the alignment control force with respect to the liquid crystal is large An alignment film is required.

In particular, as the display device of the IPS system, it is required that the light leakage be small (the black level is good) when the black display is performed. As mentioned above, in order to make black level favorable, the orientation film | membrane material which is not only large in the orientation control force with respect to a liquid crystal, but also the orientation direction of a film surface matches well by rubbing is required.

In addition, as liquid crystals having a large dielectric anisotropy are used in recent years with the lowering of the driving voltage, display stains (brightness stains) generated in the surface of the display are a problem. In particular, when water washing is performed to remove the cutting debris generated when the alignment film is rubbed, a phenomenon in which the washed water remains as a display stain may occur, which is a big problem.

Japanese Patent Laid-Open No. 11-322925 discloses that a polymer having a structural unit of the following general formula (A) can be used as a liquid crystal aligning agent. However, there is no description regarding the properties when the polymer is used as a liquid crystal aligning agent:

(A)

In addition, Japanese Unexamined Patent Application Publication No. 11-193346 discloses the use of an alignment agent obtained by mixing a polyamic acid containing a compound of the following general formula (B) with another polyamine acid solution as an alignment film, thereby providing orientation, consumption current value, VHR and It is described that it is possible to improve properties such as residual charge:

(B)

Further, Patent Publication No. 33169062 discloses that the alignment property can be improved by using an alignment agent obtained by mixing a polyamine acid containing a compound of the general formula (C) with another polyamine acid solution as an alignment film:

(C)

The present invention provides a polyamine acid or polyimide as a material for providing a liquid crystal alignment film that satisfies various characteristics required in the above-described liquid crystal display device at a high level.

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject, as a material of the liquid crystal aligning film used for a liquid crystal display element, by using the polyamine acid and / or polyimide synthesize | combined using the diamine of the structure mentioned later as a raw material, The present inventors have found that the object can be achieved, and according to this knowledge, the present invention has been completed.

This invention consists of the following.

[1] Diamine represented by the following formula (1):

(One)

[Wherein Q is-(CH ₂ ) _n -or-((CH ₂ ) ₂ O) _m (CH ₂ ) _2- , n is an integer from 3 to 10 and m is an integer from 1 to 3; A is independently a single bond or 1,4-phenylene in which any hydrogen in the benzene ring may be substituted with fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; R ¹ and R ² are independently hydrogen, fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; R ³ and R ⁴ are independently hydrogen or fluorine; X is independently a single bond, oxygen, or sulfur; Provided that when Q is-(CH ₂ ) _n- , A is a single bond, X is a single bond or sulfur, either R ¹ or R ² is fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; When A is a single bond and X is oxygen, at least one of R ¹ to R ⁴ is fluorine.

[2] The diamine according to the above [1], represented by the formula of any one of the following formulas (1-A) to (1-L):

[3] In the above formula (1), R ¹ and R ² are independently fluorine, hydrogen or tert-butyl, R ³ and R ⁴ are hydrogen, and A is a single bond or 1,4-phenylene. The diamine as described in [1] or [2].

[4] The diamine according to the above [1] or [3], wherein in formula (1), X is a single bond.

[5] The diamine according to the above [1] or [3], wherein in formula (1), X is oxygen.

[6] The diamine according to the above [1] or [3], wherein in formula (1), X is sulfur.

[7] A polyamic acid consisting of 10 to 100 mol% of structural units represented by the following formula (2-1) and 90 to 0 mol% of structural units represented by the following formula (2-2):

(2-1)

(2-2)

[Wherein Q is-(CH ₂ ) _n -or-((CH ₂ ) ₂ O) _m (CH ₂ ) _2- , n is an integer from 3 to 10 and m is an integer from 1 to 3; A is independently a single bond or 1,4-phenylene in which any hydrogen on the benzene ring may be substituted with fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; R ¹ and R ² are independently hydrogen, fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; R ³ and R ⁴ are independently hydrogen or fluorine; X is independently a single bond, oxygen or sulfur; R ⁵ is independently a tetravalent organic group having 4 to 30 carbon atoms; R ⁶ is a divalent organic group having 2 to 60 carbon atoms; Provided that when Q is-(CH ₂ ) _n- , A is a single bond, X is a single bond or a sulfur atom, either R ¹ or R ² is fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms. When A is a single bond and X is oxygen, then at least one of R ¹ , R ² , R ³ and R ⁴ is fluorine.

[8] In the formulas (2-1) and (2-2), R ⁵ is at least one of a tetravalent group selected from the group represented by the following formulas (3) to (11): 7] polyamic acid:

[Wherein, G ¹ is a single bond, alkylene having 1 to 12 carbon atoms, 1,4-phenylene or 1,4-cyclohexylene, and G ² is a single bond, -CH _2- , -CH ₂ CH _2- , -O-, -CO-, -S-, -C (CH ₃ ) _2- , or -C (CF ₃ ) _2- , X ¹ is a single bond or -CH _2- , R ³² , R ³³ , R ³⁴ , and R ³⁵ are independently hydrogen, methyl, ethyl or phenyl, R ³⁶ is hydrogen or methyl, R ³⁷ is hydrogen, methyl, ethyl or phenyl, and A ³ is independently a cyclohexane ring or Benzene ring, q is 1 or 2, and the group represented by the formula (11) includes two pairs of bonding hands in which two bonding hands are positioned at α-site of each other.

[9] The polyamine acid according to the above [8], wherein R ⁵ is independently any of groups represented by the following formulas (I) to (V):

[10] The polyamine acid according to any one of the above [7] to [9], wherein R ⁶ is any one of the following groups:

Where Bn represents benzyl.

[11] In the formula (2-1), R ¹ and R ² are independently fluorine, hydrogen or tert-butyl, R ³ and R ⁴ are hydrogen, and A is a single bond or 1,4-phenylene. And the polyamine acid according to any one of the above [7] to [10].

[12] In the formula (2-1), the group represented by the following formula (2-3), which constitutes a part thereof, is a diamine residue of the diamine represented by the formulas (1-A) to (1-L). The polyamine acid in any one of said [7]-[11] which is any of group represented by following formula (1-a)-(1-l):

(2-3)

[13] The polyamine acid according to any one of [7] to [11], in which X is a single bond in the formula (2-1).

[14] The polyamine acid according to any one of the above [7] to [11], wherein in the formula (2-1), X is oxygen.

[15] The polyamine acid according to any one of [7] to [11], in which X is sulfur in Formula (2-1).

[16] The polyamine acid according to any one of [7] to [15], wherein the weight average molecular weight is 5,000 to 500,000.

[17] A polyimide prepared by dehydrating the polyamic acid according to any one of [7] to [16].

[18] A liquid crystal aligning agent containing the polyamine acid according to any one of [7] to [16].

[19] A liquid crystal aligning agent containing the polyimide according to the above [17].

[20] A liquid crystal aligning film obtained from the liquid crystal aligning agent described in [18] or [19] above.

[21] A liquid crystal display device using the liquid crystal alignment film as described in [20] above.

Best Mode for Carrying Out the Invention

In the following description, polyamic acid and polyimide may be named generically and described as a polymer. The characteristic of this invention is using the novel diamine which has a structure represented by said Formula (1), and has the structural unit represented by Formula (2-1) using the said diamine, and optionally Formula (2- It relates to a polyamine acid having a structural unit represented by 2) and a polyimide derived from the polyamine acid. When used as a liquid crystal aligning film, the liquid crystal aligning agent which makes these polymers at least one of a component expresses the characteristic which satisfy | fills the requirements mentioned above.

In addition, the polymer of the present invention consists of a polyamic acid and a polyimide, wherein the polyimide refers to a polymer in which the amine acid of the polyamine acid is partially or completely imidated. Moreover, this invention also includes the said blend of polymers, For example, the polymer blend containing the partially imidated polymer is also called polyimide.

R <^1> and R <^2> in the said Formula (1) can be arbitrarily selected from hydrogen, fluorine, C1-C4 alkyl, and C1-C4 alkoxy.

In said formula (1), R <^3> and R <^4> can be arbitrarily selected from hydrogen and fluorine.

Among the above required characteristics, in order to reduce residual DC and prevent display defects caused by cutting of the alignment film, relatively small substituents such as methyl, ethyl, methoxy and fluorine are introduced into R ¹ , R ² , R ³ and R ⁴ . It is desirable to. In order to make the VHR of the alignment film particularly high, propyl, butyl, isopropyl, tert-butyl, ethoxy, propyloxy, butoxy, isopropoxy or tert-parts in R ¹ , R ² , R ³ and R ⁴ What is necessary is just to introduce a high substituent, such as oxy.

It is appropriate to select 1,4-phenylene as A among the above-described required characteristics, particularly when it is desired to reduce residual DC.

In General Formula (2-1), X represents a single bond, oxygen, or sulfur. At this time, when it is desired to impart high VHR by the liquid crystal aligning agent, it is preferable that X is a single bond or oxygen, and X is most preferably a single bond. For example, in the case of the liquid crystal aligning film for IPS, in order to suppress burning, the liquid crystal aligning film with small volume resistivity of a polymer is useful, described in SID International Symposium Digest, page 1166, (2003) etc. For this purpose, it is preferred that X is oxygen or sulfur, and most preferably X is sulfur.

In formulas (1) and (2-1), Q is-(CH ₂ ) _n -or-((CH ₂ ) ₂ O) _m (CH ₂ ) _2- , but rubbing while the alignment film of the present invention maintains good orientation. In order to prevent cutting at the time, n is an integer of 3-10, or m is an integer of 1-3. Preferred examples are 1,3-propylene, 1,4-butylene, 1,5-pentylene, 1,6-hexylene, 1,7-heptylene, 1,8-octylene, 1,9-no Nylene, 1,10-decylene. For example, when it is desired to make the surface energy of the liquid crystal aligning film of the present invention small for reasons such as increasing the pretilt angle, it is preferable to select-(CH ₂ ) _n -as Q. Moreover, if you want to increase the surface energy of the liquid crystal alignment film of the present invention, there is provided a Q - is preferable to select the _{- ((CH 2) 2 O} ) m (CH 2) 2.

As a preferable example of the diamine represented by said formula (1), the case where X was limited to a single bond is shown in following Tables 1-5.

In Tables 1 to 5, Ph represents 1,4-phenylene; Substitution position represents the position with respect to an amino group; Me represents methyl; Et represents ethyl; Pr represents a profile; Bu represents butyl; t-Bu stands for tert-butyl.

As a preferable example of the diamine represented by said formula (1), the case where X is limited to oxygen is shown to following Tables 6-7.

In Tables 6 and 7, Ph represents 1,4-phenylene; Substitution position represents the position with respect to an amino group; Me represents methyl; Et represents ethyl; Pr represents a profile; Bu stands for butyl and t-Bu stands for tert-butyl.

As a preferable example of the diamine represented by said formula (1), the case where X is limited to sulfur is shown to Tables 8-10.

In Tables 8 to 10, Ph represents 1, 4-phenylene; The substitution position represents a position relative to an amino group; Me represents methyl; Et represents ethyl; Pr represents a profile; Bu represents butyl; t-Bu stands for tert-butyl.

As preferable examples of the diamine represented by the formula (1), Q is _{- ((CH 2) 2 O} ) m (CH 2) 2 -, shown in Table 11, the case of.

As the tetracarboxylic dianhydride which produces the tetravalent organic group represented by R <^5> in said Formula (2-1) and (2-2) of this invention, all well-known tetracarboxylic dianhydride can be used. Especially preferable examples are shown in Tables 12-14.

Some of these compounds may contain isomers, and may be mixtures of these isomers. In addition, the tetracarboxylic dianhydride used for this invention may be other than the said compound.

The liquid crystal aligning film which consists of polyamine acid or polyimide represented by Formula (2) comprised from these tetracarboxylic dianhydrides of these preferable examples satisfies the said characteristic required as an oriented film. Therefore, it is especially excellent as an orientation film for TFT type display elements containing a liquid crystal composition with a low threshold voltage, and driving at low voltage.

In order to give a high VHR to a liquid crystal display device in particular, No.4-2, 4-12, 4-13, 4-14, 4-15, 4-16, 4-17, 4-18, 4-20 At least one compound having an alicyclic skeleton, such as 4-21, 4-22, 4-23, 4-24, 4-28, 4-29, 4-30, 4-31, 4-32, 4-38 By the selection, the above object can be achieved. In addition, especially if you want to prevent the burning phenomenon, No.4-1, 4-3, 4-4, 4-5, 4-6, 4-7, 4-8, 4-9, 4-10, 4 This can be achieved by appropriately combining compounds such as -11 and 4-19 with other compounds.

As a diamine which produces the organic group represented by R <^6> of the said Formula (2-2), all well-known diamine can be used. In particular, preferable examples are shown in Tables 15 to 17 below.

The liquid crystal aligning film which has a structural unit represented by Formula (2-1) comprised from diamine of these preferable examples, and optionally contains the structural unit represented by Formula (2-2) is all required as an oriented film. Satisfies the above characteristics. Therefore, it contains especially the liquid crystal composition with a low threshold voltage, and is especially excellent for the oriented film of TFT type display elements which drive by low voltage.

The pretilt angle of the liquid crystal is generally controlled by changing the size of the side chains of the polyamic acid or the polyimide, and in most cases, this is done by changing the size of the diamine residues. As R ⁶ of the formula (2-2), diamines represented by preferred examples No. 5-1 to 5-33, 5-35, 5-37, and 5-40 to 5-42 of Table 5 are used. In this case, it is particularly suitable as an alignment film for the IPS mode in which a small pretilt angle is required. In addition, when using diamines represented by Nos. 5-33 to 5-36, 5-38, 5-39, and 5-43 to 5-52, TN, OCB, and VA, which require a relatively large pretilt angle, are required. It is especially suitable as a molten alignment film. Considering these points collectively, preferred R 6 is No. 5-8, 5-12, 5-13, 5-18, 5-22, 5-36, 5-37, 5-38, 5-41, 5 -42, 5-44, 5-46.

In order to more effectively express the characteristics required for the alignment film, a method of mixing two or more kinds of varnishes in which a polymer having a different surface energy value is dissolved in a solvent when thinned (hereinafter referred to as a polymer blend) is often performed. For example, Japanese Unexamined Patent Application Publication No. 8-43831 discloses a good liquid crystal alignment characteristic by using a characteristic in which a component having a small surface tension tends to spontaneously separate to a film surface when a resin coating film is formed from a polymer mixture of two or more components. By reducing the surface tension of the resin coating film, which exhibits good electrical properties, by 2dyne / cm or less than the surface tension of the resin coating film in which good electrical properties are expressed, a resin showing good liquid crystal alignment property is formed on the surface of the alignment film, and good electrical properties are expressed inside the alignment film. A method of forming a resin to obtain an alignment film is disclosed.

In order to improve the properties required for the alignment film, the polyamine acid of the present invention and the polyimide derived therefrom can also be polymer blended between different polymers of the present invention or polymers of the present invention and other polymers for the above-mentioned purposes. Do.

The polymer which has a structural unit represented by the said General formula (2-1) has especially excellent liquid-crystal orientation. Therefore, when polymer blending the polymer of this invention with another polymer, when the polymer of this invention is used as a component with small surface tension, the alignment film which the stable liquid crystal aligning characteristic can express effectively can be obtained. For this purpose, it is suitable to use the substituent which has a large side chain already demonstrated as R <^6> of the structural unit represented by General formula (2-2).

The polymer blend can be obtained by mixing a different polymer solution of the present invention or a solution of the polymer solution of the present invention with another polymer to form a mixture, and removing the solvent from the mixture solution. To prepare the alignment film from the mixture solution, it is used as a solution (varnish) diluted with a suitable solvent. If the density | concentration of each component of the polymer of the said mixture solution is as desired, it can also be used for manufacture of an oriented film as it is, without diluting.

An organosilicon compound or the like may be added to the liquid crystal aligning agent of the present invention in order to further improve the characteristics of the liquid crystal aligning film of the present invention and to improve the adhesion of the alignment film to the glass substrate or to control the hardness.

As an organosilicon compound added to the liquid crystal aligning agent of this invention, in order to improve the adhesiveness to a glass substrate of a oriented film, or hardness adjustment, the example of a silane coupling agent is aminopropyl trimethoxysilane, aminopropyl tree. Methoxysilane, vinyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) 3-aminopropyltrimethoxysilane, vinyltriethoxysilane, 3 -Methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, Examples of silicone oils are dimethylpolysiloxane, polydimethylsiloxane and polydiphenylsiloxane. The amount of the organosilicon compound added to the alignment agent is 0.01 to 5% by weight, preferably 0.1 to 3% by weight, based on the reaction product solids contained in the alignment agent.

Examples of the solvent used to prepare each liquid crystal aligning agent of the present invention include N-methyl-2-pyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide (DMAc), and dimethyl sulfoxide (DMSO). ), Ethylene glycol monobutyl ether (BC), ethylene glycol monoethyl ether and γ-butyrolactone. You may use these in mixture of 2 or more types. Moreover, even if it is other than the said solvent, if a reaction product is soluble, it will not be limited to these.

In order to make application to a glass substrate easy and to prevent cutting at the time of rubbing, the weight average molecular weight of the polyamine acid of this invention becomes like this. Preferably it is 5,000-500,000, More preferably, it is 10,000-100,000. Moreover, when apply | coating by the printing by the latest inkjet method, these molecular weights become like this. Preferably it is 5,000-100,000, More preferably, it is 10,000-50,000. As polyimide of this invention, the polyimide derived from the polyamine acid of the said molecular weight is preferable.

At a concentration of 0.1 to 30% by weight, preferably 1 to 10% by weight of the total weight of the solvent, one or more polymers of the present invention and other components are dissolved to prepare a liquid crystal aligning agent, and brush-coated the aligning agent. It is apply | coated on a board | substrate by the method, immersion method, the spinner method, the spray method, the printing method, etc. Thereafter, the solvent is evaporated at 50 to 150 ° C, preferably 80 to 120 ° C, and then heated at 150 to 400 ° C, preferably 180 to 280 ° C to form a film. If the surface of the substrate is treated with a silane coupling agent before application and a film is formed thereon, the adhesion between the film and the substrate can be improved. Thereafter, when the surface of the film is rubbed in one direction with cloth or the like, an alignment film is obtained.

Although the liquid crystal aligning agent containing the polymer of this invention by such a structure can be used as an oriented film, a protective film, an insulating film, etc., it is the most suitable especially as an oriented film for liquid crystal display elements. The said aligning agent can also mix other high molecular compounds, such as a polyamideimide and a polyamide.

Moreover, the polymer of this invention can be used for various polyimide coating agents, a polyimide resin molded article, a film, a fiber, etc. other than a liquid crystal aligning film.

The compound represented by the said Formula (1) of this invention can be synthesize | combined by the method described below.

(1) when A is a single bond:

(Wherein Q, R ¹ , R ² , R ³ , and R ⁴ are as described above, Prt. Represents a protecting group and T represents a straight or branched alkylene having 1 to 8 carbon atoms).

First step ; Commercially available phenol derivatives represented by formula (1-1) are Bull. Chem. Soc. According to Jpn., 60, 4187 (1987) or Synlett, 1241 (1997) and the like, a bromination reaction is carried out to obtain a compound represented by formula (1-2).

Second step ; According to a conventional method, the compound represented by formula (1-2) is protected with a protecting group such as methyl or benzyl.

Third step ; According to Organic Reaction, 22, 253 (1975) and the like, a compound represented by the formula (1-3) is used as a Grignard reagent, a coupling reaction with an acid chloride represented by the formula (1-4), followed by a hydrolysis by an acid. By decomposition, the target compound represented by formula (1-5) is obtained.

Fourth step ; The compound represented by formula (1-5) is converted to the compound represented by formula (1-7) by silane reduction or Wolff-Kishner reduction.

Fifth step ; According to a conventional method, the compound represented by the formula (1-7) is chlorinated with thionyl chloride or the like to obtain a compound represented by the formula (1-8), and represented by the formula (1-9) as described above. Reaction with a compound yields the compound represented by formula (1-10).

Sixth step ; By deprotecting the compound represented by Formula (1-10), the compound represented by Formula (1-11) is obtained. This compound is reacted with trifluoroacetic anhydride or the like according to a conventional method to obtain a compound represented by formula (1-12).

Seventh step ; According to Tetrahedron Lett., 38, 6367 (1997) and the like, the compound represented by the target formula (1) is obtained by converting the triflate group to an amino group.

Compounds wherein R ¹ = R ² and R ³ = R ⁴ are further used in the above reaction by using a compound represented by formula (1-3) of twice the equivalent of the compound represented by formula (1-4). It can be synthesized easily.

(2) when A is 1,4-phenylene:

(Wherein R ⁵ , R ⁶ , R ⁷ and R ⁸ represent hydrogen, alkyl having 1 to 4 carbon atoms, alkoxy or fluorine).

The compound represented by formula (1-12) is described in J. Org. It is obtained by reacting with a boronic acid derivative represented by a compound represented by the formula (1-13) according to the method of Chem., 58, 2201 (1993) and Synthesis, 735 (1993). In this case, the compound represented by the formula (1-13) is J. Am. Chem. Soc., 80, 3609 (1958) and US Pat. No. 4,462,819 and the like.

The compound represented by Formula (1) of the present invention can also be synthesized by the method shown in Examples described later.

EXAMPLE

Hereinafter, the product obtained by using the polymer of this invention, ie, the liquid crystal aligning agent of polyimide resin, is demonstrated in detail by an Example. In the examples, the reactions were all carried out under a nitrogen atmosphere, the molecular weight was measured using a standard solution of polystyrene by the GPC method, and the eluate was measured using DMF. Furthermore, the present invention is not limited to these examples.

Evaluation method of liquid crystal display element

Hereinafter, the evaluation method of the liquid crystal display element used in the present Example is described.

1. Pretilt angle

It carried out by the crystal rotation method.

2. Burning phenomenon (residual charge)

Residual electric charge was measured by the method of "theology report, EID91-111, p19 other than Miyake." The measurement was carried out by superimposing a 50 mV, 1 kHz alternating current and a low frequency triangular wave with a frequency of 0.0036 Hz in the liquid crystal cell. The residual charge was used as an index of the burning phenomenon. That is, the more the residual charge, the more likely the burning phenomenon occurs.

3. Voltage maintenance rate

It carried out according to the method described in "The 14th liquid crystal discussion meeting p78 except for Mizushima." The measurement conditions were 69 microseconds of gate width, frequency 60 Hz, and wavelength height ± 4.5V.

4. Liquid crystal alignment, black level

Visual inspection was performed using a polarization microscope. In particular, the black level was observed in the state of making the incident light and the rubbing direction of the cell the same in a cross nicol state.

5. Cutting

Visual inspection was performed using a microscope.

Example 1

(1,3-bis (4-amino-2-methylphenyl) propane; synthesis of compound No. 1-2)

4-bromo-2-methylbenzaldehyde [synthesized according to Chem. Ber., 102, 2493 (1969)] (10.0 g, 50 mmol), methyl (methylthio) methylsulfoxide (12.4 g, 100 mmol) and trimethylbenzylammonium The mixture of hydroxide 40% methanol solution (10 ml) was refluxed for 5 hours. After cooling, toluene (50 ml) and pure water (50 ml) were added and the extraction operation was performed. The organic layer was washed with 0.5 M aqueous sulfuric acid (50 ml) and pure water (50 ml × 2), which was dried over anhydrous magnesium sulfate. Filtration and the solvent were distilled off under reduced pressure to obtain crude crystals of the desired product. Ethanol (20 ml) and 6M HCl (20 ml) were added to the compound and refluxed for 5 hours. After the solvent was removed under reduced pressure, the same extraction procedure as described above was performed with ethyl acetate (50 ml) and pure water (50 ml) for the remainder. The obtained composition was recrystallized in alcohol to obtain the desired 4-bromo-2-methylphenylacetic acid. Yield 7.4 g (64%).

The compound (7.4 g, 32 mmol) and iron powder (1.8 g, 32 mmol) were heated at 250 ° C. for 30 minutes. After cooling, toluene (100 ml) was added and the insolubles were filtered off. After removing toluene under reduced pressure, the remainder was purified by column chromatography (silica gel / toluene) to obtain the desired 1,3-bis (4-bromo-2-methylphenyl) -2-propanol. Yield 3.8 g (60%).

The diethylene glycol (10 ml) solution of the compound (3.8 g, 9.6 mmol), hydrazine monohydrate (1.9 ml, 39 mmol), and KOH (0.77 g, 19 mmol) was stirred at 140 ° C. for 1 hour and 200 ° C. for 2 hours. . After cooling, extraction was performed with toluene (50 ml) and pure water (50 ml). The same operation as described above was carried out, and the remainder was purified by column chromatography (silica gel / heptane) to obtain the desired 1,3-bis (4-bromo-2-methylphenyl) propane. Yield 3.4 g (92%).

Compound (3.4 g, 8.9 mmol), benzophenone imine (3.9 g, 21 mmol), palladium acetate (40 mg, 0.18 mmol), 2,2'-bis (diphenylphosphino) -1,1'-binafyl (BINAP, 166 mg, 0.27 mmol), and a mixture of cesium carbonate (4.0 g, 12 mmol) were refluxed in toluene (20 ml) for 7 hours. After cooling, toluene (40 ml) and pure water (50 ml) were added and extracted. The operation was carried out in the same manner as described above, and the remainder was purified by column chromatography (silica gel / toluene). This was 5% Pd / C and hydrocracked in toluene-alcohol (1: 1, 100 ml) according to a conventional method. After filtration of the catalyst, the solvent was removed under reduced pressure. The remainder was recrystallized with ethanol to obtain the desired 1,3-bis (4-amino-2-methylphenyl) propane. Recovery 1.4 g (61%).

Example 2

(1,3-bis- (4-amino-2-fluorophenyl) propane; synthesis of compound No.1-17)

In the same manner as in Example 1 using 4-bromo-2-fluorophenylacetic acid (8.0 g, 34 mmol, synthesized by the method described in JP-A 62-252774) and iron powder (1.9 g, 34 mmol) Reacted. The remainder was purified by column chromatography (silica gel / toluene) to give the desired 1,3-bis (4-bromo-2fluorophenyl) -2-propanol. Yield 4.0 g (58%).

The compound was converted as described above to obtain the desired 1,3-bis- (4-amino-2-fluorophenyl) propane.

The yield and purification conditions of each step are shown below:

Wolff-Kishner Reduction; Purification: column chromatography (silica gel / heptane). Yield: 90%.

Benzophenone iminolation; Purification: column chromatography (silica gel / heptane).

Hydrocracking; Purification: Recrystallization (ethanol). Yield 64%.

Example 3

(1,5-bis (4-amino-2-methylphenyl) pentane; synthesis of compound No.1-35)

Grignard reagent (solvent THF) prepared according to a conventional method from 4-bromo-3-methylanisole (25g, 124mmol) and magnesium (3.3g, 135mmol), THF (200ml) of copper iodide (24g, 126mmol) To the solution was added below 0 ° C. To the above, a THF (50 ml) solution of glutaric acid chloride (10.5 g, 67 mmol) was further added at 0 ° C or below. After stirring for 30 min at room temperature, the reaction was added dropwise in 3N HCl (100 ml). The extraction operation was carried out with toluene as described above. The crude product obtained was purified by column chromatography (silica gel / toluene) to give the desired 1,5-bis (4-methoxy-2-methylphenyl) -1,5-pentadione. Recovery 9.1g (43%).

To a mixture of the compound (9.0 g, 26 mmol), titanium tetrachloride (19.4 g, 104 mmol), and methylene chloride (80 ml), 18.6 ml (114 mmol) of triethylsilane were added at room temperature, and the mixture was stirred at room temperature as it was for 2 hours. After the reaction, the reaction mixture was poured into ice water, and extraction was performed in the same manner as described above. The hexaethyl siloxane produced | generated by reaction was removed by distillation under reduced pressure, and the target 1, 5-bis (4-methoxy- 2-methylphenyl) pentane was obtained. The said compound was used for the next reaction as it was, without refine | purifying.

To a methylene chloride (80 ml) solution of the compound (8.3 g, 26 mmol) was added boron tribromide (13 g, 52 mmol) at −50 ° C. or lower. After stirring at room temperature overnight, the reaction was added to pure water (80 ml). After the same extraction procedure as described above, the resultant was recrystallized (cyclohexane) to obtain the desired 1,5-bis (4-hydroxy-2-methylphenyl) pentane. 6.3 g (86%) recovery.

To a pyridine (20 ml) solution of the compound (6.3 g, 22 mmol) was added trifluoromethane sulfonic anhydride (13.7 g, 49 mmol) at 0-5 ° C. After stirring overnight at room temperature, the pyridine was removed under reduced pressure and the extraction operation was performed with toluene-pure water. The obtained crude product was purified by column chromatography (silica gel / toluene) to obtain the desired 1,5-bis (4-trifluoromethanesulfonyloxy-2-methylphenyl) pentane. Recovery 10.7 g (89%).

A mixture of the above compound (10.0 g, 18 mmol), benzophenone imine (7.3 g, 40 mmol), palladium acetate (81 mg, 0.36 mmol), BINAP (332 mg, 0.54 mmol) and cesium carbonate (16.8 g, 54 mmol) was added to THF (100 ml). ) For 20 hours. After cooling, the solvent was removed under reduced pressure, and toluene (200 ml) and pure water (200 ml) were added and extracted. The same operation as described above was carried out, and the rest was purified by column chromatography (silica gel / toluene). This was 5% Pd / C, and hydrocracked in toluene-alcohol (1: 1, 200 ml) according to a conventional method. After filtration of the catalyst, the solvent was removed under reduced pressure. The residue was recrystallized from ethanol to obtain the desired 1,5-bis (4-amino-2-methylphenyl) pentane. Yield 2.3 g (45%).

Example 4

(1,5-bis (4- (4-aminophenyl) -2-methylphenyl) pentane; synthesis of compound No.1-118)

1,5-bis (4-trifluoromethanesulfonyloxy-2-methylphenyl) pentane (4.0 g, 7.3 mmol) synthesized in Example 3, J. Am. Chem. 4-aminophenylboronic acid (2.0 g, 15 mmol), tetrakistriphenylphosphinopalladium (0) (210 mg, 0.18 mmol) and sodium carbonate (5.7 g, 54 mmol) synthesized according to Soc., 80, 3609 (1958) The mixture of was refluxed in toluene / alcohol / pure = 1/1/1 (v / v / v, 60 ml) for 8 hours. After cooling, an extraction operation was performed in a toluene-pure system. The crude product obtained by the same operation as described above was purified by column chromatography (silica gel / toluene: methanol = 20: 1) to obtain the desired 1,5-bis (4- (4-aminophenyl) -2-methylphenyl Pentane was obtained. 1.8 g (57%) recovery.

Example 4-2

(1,3-bis (4- (4-aminophenyl) phenyl) propane; synthesis of compound No. 1-100)

1,3-bis (4-bromophenyl) propane (10.0 g, 28 mmol), synthesized according to WO8803134, J. Am. Chem. Of 4-aminophenylboronic acid (7.7 g, 56 mmol), tetrakis liphenylphosphinopalladium (0) (780 mg, 0.67 mmol) and sodium carbonate (21 g, 200 mmol) synthesized according to Soc., 80, 3609 (1958) The mixture was refluxed in toluene / alcohol / pure = 1/1/1 (v / v / v, 300 ml) for 8 hours. After cooling, the extraction operation was carried out in a toluene-pure system. The crude product obtained by the same operation as described above was purified by column chromatography (silica gel / toluene: methanol = 20: 1) to obtain the desired 1,3-bis ((4- (4-aminophenyl) phenyl) propane Yield 16 g (54%).

Example 5

(1,4-bis (4-amino-2-t-butylphenyloxy) butane; synthesis of compound No.2-19)

J. Org. Using 4-nitro-2-tert-butylphenol (4.8 g, 25 mmol) and 1,4-dibromo butane (2.6 g, 12 mmol) synthesized according to the method described in Chem., 33, 223, (1968) J. Polym. Sci., Part A, Polym. The compound was synthesized according to the same method as Chem., 31, 1423 (1993).

Example 5-2

(Synthesis of di (2- (4-aminophenylsulfanyl) ethyl) ether; Synthesis of Compound No. 4-6)

4-nitrothiophenol (20.0 g, 129 mmol), 2-chloroethyl ether (9.2 g, 64 mmol), and K ₂ CO ₃ (21 g, 150 mmol) were reacted in DMF (100 ml) at 80 ° C. for 4 hours. After cooling, pure water (100 ml) and methylene chloride (200 ml) were added and extracted to the reaction solution. The organic layer was washed twice with pure water (100 ml) and then dried over anhydrous magnesium sulfate. After filtration and removal of the solvent under reduced pressure, the remainder was purified by column chromatography (silica gel / methylene chloride) and recrystallization (toluene) to obtain the desired di (2- (4-nitrophenylsulfanyl) ethyl) ether. Recovery 22 g (91%).

The compound (22 g, 58 mmol) and iron powder (19 g, 340 mmol) were dissolved in 50% aqueous ethanol solution (40 ml) and refluxed under nitrogen stream. 1N hydrochloric acid 50% aqueous ethanol solution (20 ml) was slowly added dropwise thereto. After dropping, the mixture was refluxed again for 3 hours. After cooling, an aqueous 30% NaOH solution was added to bring the pH to 12. Methylene chloride (100 ml) was added to the reaction solution, and the mixture was filtered through Celite. The organic layer was washed twice with pure water (100 ml) and then dried over anhydrous magnesium sulfate. After filtering and removing the solvent under reduced pressure, the target product was obtained by column chromatography (silica gel / methylene chloride: methanol = 1: 1) and recrystallization (ethanol). Recovery 14 g (74%).

Example 5-3

(Synthesis of 1,4-bis (4′-aminodiphenyl-4-sulfanyl) butane; Synthesis of Compound No.3-64)

Instead of 4-nitrothio phenol, J. Am. Che. Soc., 200, 122 (3688) -based 4- (4-nitrophenyl) thiophenol, instead of 2-chloroethyl ether, 1,4-di It synthesize | combined by the method similar to Example 5-2 except using bromobutane. Total yield 54%.

Example 6

(Preparation of the liquid crystal aligning agent 6 containing polyamine acid 6 and the said polyamine acid 6)

In a 100 ml four-necked flask equipped with a stirrer, a nitrogen inlet, a thermometer, and a raw material inlet, 1.145 g (4.500 mmol) of 1,3-bis (4-amino-2-methylphenyl) propane synthesized in Example 1 was added. It was added and dissolved in 10 g of NMP. 0.4908 g (2.250 mmol) of pyromellitic dianhydride (hereinafter referred to as PMDA) and 0.4412 g (2.250 mmol) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride (hereinafter referred to as CBTA) were added. , Was stirred for 6 hours. Thereafter, the solution was diluted with 29 g of NMP to obtain a clear solution having a polyamic acid concentration of about 5% by weight. The weight average molecular weight of the polymer was 50,000, and the viscosity at 25 ° C. of the solution was 35 mPa · s. Hereinafter, this solution is called liquid crystal aligning agent 6.

Example 7

(Preparation of the liquid crystal aligning agent 7 containing polyamine acid 7 and the said polyamine acid 7)

Instead of 1,3-bis (4-amino-2-methylphenyl) propane, using 1.1803 g (4.500 mmol) of 1,3-bis (4-amino-2-fluorophenyl) propane synthesized in Example 2 Other than that, varnish was obtained based on Example 5. The weight average molecular weight of this polymer was 5.50,000, and the viscosity in 25 degreeC of this solution was 32 mPa * s. Hereinafter, the solution is referred to as liquid crystal aligning agent 7.

Example 8

(Preparation of the liquid crystal aligning agent 8 containing a polyimide and the said polyimide)

4.6 g (45 mmol) of acetic anhydride was added to varnish 1 prepared in the method of Example 6, and the mixture was reacted at 100 ° C for 1 hour. After cooling, the reaction solution was added to 100 ml of pure water, and the resulting precipitate was filtered off. The precipitate was washed with pure water (25 ml) and methanol (25 ml), which was dried in vacuo to give a polyimide. For physical property evaluation, the polymer was dissolved in NMP and used as a solution having a concentration of 5%. Hereinafter, the solution is called liquid crystal aligning agent 8.

The liquid crystal aligning agent shown in Table 18 was prepared according to the method according to Examples 6 and 7.

Example 22

6.7 g of BC was added to 10 g of liquid crystal aligning agent 6 (prepared in Example 6), and the solution of about 3 weight% of concentration was obtained to a screw vial. On the transparent glass substrate provided with the ITO electrode on one side, the said solution was dripped and apply | coated by the spinner method (2500 rpm, 15 second). After application | coating, it heated at 80 degreeC for 5 minutes, evaporated the solvent, heat-processed at 250 degreeC for 30 minutes in oven, and obtained the polyimide resin thin film of about 60 nm in film thickness. The glass substrate in which the said resin thin film was formed was rubbed, these two sheets were stuck so that a rubbing direction might become antiparallel, and the liquid crystal cell of 20 micrometers of cell thickness was assembled. The liquid crystal composition A which consists of the following compounds was injected into the said cell, the isotropic process was performed at 110 degreeC for 30 minutes, it cooled to room temperature, and the liquid crystal display element was obtained. The residual DC of the liquid crystal display device was 0.25 V at 25 ° C., and VHR at 20, 60, and 90 ° C. was 99.6, 98.9, and 96.7%, respectively. Moreover, as a result of measuring the pretilt angle using the said display element, it was 1.2 degree | times. Furthermore, as a result of observation by a microscope, the orientation defect of the liquid crystal was not observed and the black level was also favorable. Also no cutting was observed. (Hereinafter, these measured values are referred to as initial values.)

The cells were allowed to stand at 110 ° C. for 20 hours, and cooled to room temperature, and then these values were measured again. As a result, the residual DC was 0.26 V (25 ° C.), the VHR was 99.5 (20), 98.5 (60), 96.3% (90 ° C.), and the pretilt angle was 1.2 degrees. Moreover, the orientation defect of the liquid crystal was not observed and the black level was also favorable. No cutting was also observed (hereinafter, these measured values were defined as values after heating).

Liquid Crystal Composition A

Example 23

Except having used the liquid crystal aligning agent 7 instead of the liquid crystal aligning agent 6, the liquid crystal display element was produced by the method according to Example 22, and the characteristic was measured.

Initial value: residual DC; 0.29 V, VHR; 99.1 (20), 96.3 (60), 94.9 (90 ° C.)%, Pretilt angle; 1.3 degrees. No orientation defects and no cuts. Black level is good.

Value after heating: residual DC; 0.30 V, VHR; 99.0 (20), 96.2 (60), 94.7 (90 ° C.)%, Pretilt angle; 1.2 degrees. No orientation defects and no cuts. Black level is good.

According to Examples 22 and 23, the following liquid crystal display elements were produced, and the characteristics were measured.

Example 28

A liquid crystal display device was manufactured in accordance with Example 22, except that the liquid crystal aligning agent 6 was changed to a mixture [liquid crystal aligning agent 6: liquid crystal aligning agent 21 = 10: 1 (weight ratio)] of the liquid crystal aligning agent 6 and the liquid crystal aligning agent 21. It produced and measured the characteristic.

Initial value: residual DC; 0.48 V, VHR; 98.4 (20), 97.4 (60), 95.2 (90 ° C.)%, Pretilt angle; 7.5 degrees. No orientation defect. Black level is good.

Value after heating: residual DC; 0.53 V, VHR; 98.3 (20), 97.5 (60), 94.5 (90 ° C.)%, Pretilt angle; 7.6 degrees. No orientation defect. Black level is good.

Comparative Example 1

According to patent 1587418, the liquid crystal aligning agent A was prepared according to the method of Example 6 using compound No. 4-2 and compound No. 5-13. Except having used the liquid crystal aligning agent A instead of the liquid crystal aligning agent 6, the liquid crystal display element was produced by the method according to Example 22, and the characteristic was measured. The results are shown in Table 20.

When the liquid crystal aligning agent of this invention is used through the comparison of Examples 22-27 and the comparative example 1, it turns out that the display element with a favorable orientation and a black level can be manufactured, without degrading characteristics, such as residual DC and VHR. Can be.

Comparative Example 2

According to Unexamined-Japanese-Patent No. 5-43687, the liquid crystal aligning agent B was prepared according to the method of Example 6 with the following compositions. Except having used the liquid crystal aligning agent B instead of the liquid crystal aligning agent 6, the liquid crystal display element was produced by the method according to Example 22, and the characteristic was measured. The results are shown in Table 21.

Acid anhydride: compound No. 4-1 100 mol%

Diamine: Compound No. 5-8 80 mol%

      Compound No.5-1 120mol%

From the comparison between Example 29 and Comparative Example 2, it can be seen that the liquid crystal alignment film of the present invention has a low residual DC (V) and a high VHR even if the alignment film gives the same degree of pretilt angle. Furthermore, it turns out that especially the orientation of a liquid crystal is good.

Comparative Example 3

According to patent 33169062, the liquid crystal aligning agent C was prepared according to the method of Example 6 with the following compositions. Except having used the liquid crystal aligning agent C instead of the liquid crystal aligning agent 6, the liquid crystal display element was produced by the method according to Example 22, and the characteristic was measured.

The results are shown in Table 22.

Acid anhydrides; Compound No. 4-1 (Table 1), 100 mol%

Diamine; , 100mol%

It can be seen from the comparison between Example 26 and Comparative Example 3 that the liquid crystal aligning agent of the present invention has a high VHR.

The liquid crystal aligning agent of the present invention exhibits a stable pretilt angle, has a high voltage holding ratio (VHR), has a low residual DC, is hard to generate display stains, and the like. It is a liquid crystal aligning agent which expresses the outstanding orientation especially while filling.

FIG. 1 is an infrared absorption spectrum of a sample obtained by reprecipitating the polyamic acid synthesized in Example 6, filtering it, and drying under vacuum.

Claims (24)

 Diamine represented by following formula (1): (One) [Wherein Q is-(CH ₂ ) _n -or-((CH ₂ ) ₂ O) _m (CH ₂ ) _2- , n is an integer from 3 to 10 and m is an integer from 1 to 3; A is independently a single bond or 1,4-phenylene in which any hydrogen in the benzene ring may be substituted with fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; R ¹ and R ² are independently hydrogen, fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; R ³ and R ⁴ are independently hydrogen or fluorine; X is independently a single bond, oxygen or sulfur; Provided that when Q is-(CH ₂ ) _n- , A is a single bond, X is a single bond or sulfur, either R ¹ or R ² is fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; When A is a single bond and X is oxygen, at least one of R ¹ to R ⁴ is fluorine. The diamine according to claim 1, which is represented by one of the following formulas (1-A) to (1-L): A compound according to claim 1, wherein in formula (1), R ¹ and R ² are independently fluorine, hydrogen or tert-butyl, R ³ and R ⁴ are hydrogen, and A is a single bond or 1,4-phenylene Diamine characterized by the above-mentioned. The compound according to claim 2, wherein in formula (1), R ¹ and R ² are independently fluorine, hydrogen or tert-butyl, R ³ and R ⁴ are hydrogen, and A is a single bond or 1,4-phenylene Diamine characterized by the above-mentioned. The diamine according to any one of claims 1, 3 and 4, wherein X is a single bond. The diamine according to any one of claims 1, 3 and 4, wherein X is oxygen. Diamine according to any one of claims 1, 3 and 4, wherein X is sulfur. Polyamine acid which consists of 10-100 mol% of structural units represented by following formula (2-1), and 90-0 mol% of structural units represented by following formula (2-2): (2-1) (2-2) [Wherein Q is-(CH ₂ ) _n -or-((CH ₂ ) ₂ O) _m (CH ₂ ) _2- , n is an integer from 3 to 10 and m is an integer from 1 to 3; A is independently a single bond or 1,4-phenylene in which any hydrogen on the benzene ring may be substituted with fluorine, alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbon atoms; R ¹ and R ² are independently hydrogen, fluorine, alkyl having 1 to 4 carbons or alkoxy having 1 to 4 carbons; R ³ and R ⁴ are independently hydrogen or fluorine; X is independently a single bond, oxygen or sulfur; R ⁵ is independently a tetravalent organic group having 4 to 30 carbon atoms; R ⁶ is a divalent organic group having 2 to 60 carbon atoms; provided that when Q is-(CH ₂ ) _n- , A is a single bond, X is a single bond or a sulfur atom, one of R ¹ and R ² is fluorine; , Alkyl having 1 to 4 carbon atoms or alkoxy having 1 to 4 carbon atoms, and when A is a single bond and X is oxygen, at least one of R ¹ , R ² , R ³ and R ⁴ is fluorine. 8. In the formulas (2-1) and (2-2), R ⁵ is independently at least one of a tetravalent group selected from the groups represented by the following formulas (3) to (11): Characterized polyamic acid: [Wherein, G ¹ is a single bond, alkylene having 1 to 12 carbon atoms, 1,4-phenylene or 1,4-cyclohexylene, and G ² is a single bond, -CH _2- , -CH ₂ CH _2- , -O-, -CO-, -S-, -C (CH ₃ ) _2- , or -C (CF ₃ ) _2- , X ¹ is a single bond or -CH _2- , R ³² , R ³³ , R ³⁴ , and R ³⁵ are independently hydrogen, methyl, ethyl or phenyl, R ³⁶ is hydrogen or methyl, R ³⁷ is hydrogen, methyl, ethyl or phenyl, and A ³ is independently a cyclohexane ring or Benzene ring, q is 1 or 2, and the group represented by the formula (11) includes two pairs of bonding hands in which two bonding hands are positioned at α-site of each other. The polyamine acid according to claim 9, wherein R ⁵ is independently any one of groups represented by the following formulas (I) to (V): . The polyamine acid of claim 8, wherein R ⁶ is any one of the following groups: Where Bn represents benzyl. The compound according to claim 8, wherein in formula (2-1), R ¹ and R ² are independently fluorine, hydrogen or tert-butyl, R ³ and R ⁴ are hydrogen, and A is a single bond or 1,4- It is phenylene, Polyamine acid characterized by the above-mentioned. The group represented by following formula (2-3) which is a group which comprises a part of said formula (2-1) is a diamine of Claim 8 represented by said Formula (1-A)-(1-L). A polyamine acid, which is any one of groups represented by the following formulas (1-a) to (1-l) which are diamine residues: (2-3) The polyamine acid according to claim 8, wherein in formula (2-1), X is a single bond. The polyamine acid of Claim 8 whose X is oxygen in said Formula (2-1). The polyamine acid of Claim 8 whose X is sulfur in said Formula (2-1). 9. The polyamic acid according to claim 8, wherein the weight average molecular weight is 5,000 to 500,000. Polyimide obtained by dehydrating the polyamic acid according to any one of claims 8 to 17. The liquid crystal aligning agent containing the polyamine acid in any one of Claims 8-17. The liquid crystal aligning agent containing the polyimide of Claim 18. The liquid crystal aligning film obtained from the liquid crystal aligning agent of Claim 19. The liquid crystal aligning film obtained from the liquid crystal aligning agent of Claim 20. The liquid crystal display element using the liquid crystal aligning film of Claim 21. The display element using the liquid crystal aligning film of Claim 22.