KR102369136B1 - Liquid crystal aligning agent, liquid crystal aligning film, and liquid crystal display element using same - Google Patents

Abstract

(R¹, R² 는 수소 원자 또는 1 가의 유기기이다. 벤젠 고리의 임의의 수소 원자는 1 가의 유기기로 치환되어 있어도 된다. * 는, 결합 부위를 나타낸다)A liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element from which it is excellent in voltage retention, relaxation of the accumulation|storage charge is quick, and the liquid crystal aligning film which a flicker does not generate|occur|produce easily during drive is provided.
The polymer obtained from diamine which has a structure shown by following formula (1), and organic solvent are contained, The liquid crystal aligning agent characterized by the above-mentioned.
[Formula 1]

(R ¹ , R ² are a hydrogen atom or a monovalent organic group. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group. * represents a bonding site)

Description

Liquid crystal aligning agent, liquid crystal aligning film, and liquid crystal display element using same

TECHNICAL FIELD This invention relates to the liquid crystal aligning agent which uses a novel polymer, a liquid crystal aligning film, and the liquid crystal display element using the same.

DESCRIPTION OF RELATED ART Liquid crystal display elements are widely used as display parts, such as a PC, a mobile phone, a smart phone, and a television. The liquid crystal display device includes, for example, a liquid crystal layer sandwiched between the device substrate and the color filter substrate, a pixel electrode and a common electrode for applying an electric field to the liquid crystal layer, an alignment film for controlling the alignment of liquid crystal molecules in the liquid crystal layer, and a pixel electrode A thin film transistor (TFT) for switching the supplied electrical signal is provided. As a driving method of liquid crystal molecules, a longitudinal electric field system, such as a TN system and a VA system, and a transverse electric field system, such as an IPS system and an FFS system, are known. In the transverse electric field method in which electrodes are formed only on one side of the substrate and an electric field is applied in a direction parallel to the substrate, compared to the conventional vertical electric field method in which a voltage is applied to electrodes formed on upper and lower substrates to drive liquid crystals, wide viewing angle characteristics and is known as a liquid crystal display device capable of high-quality display.

The transverse electric field type liquid crystal cell has excellent viewing angle characteristics, but since there are few electrode portions formed in the substrate, if the voltage retention is low, a sufficient voltage is not applied to the liquid crystal and display contrast decreases. Moreover, when stability of a liquid-crystal orientation is small, when a liquid crystal is driven for a long time, since a liquid crystal will not return to an initial state, and it will become a cause of a contrast fall and an afterimage, stability of a liquid-crystal orientation is important. In addition, static electricity is easy to accumulate in the liquid crystal cell, and even by application of a positive and negative asymmetric voltage generated by driving, electric charges are accumulated in the liquid crystal cell, and these accumulated charges affect the display as disturbance of liquid crystal alignment or an afterimage. This significantly reduces the display quality of the liquid crystal element. In addition, there arise problems such as charge accumulation even when backlight light is irradiated to a liquid crystal cell immediately after driving, an afterimage is generated even when driving for a short time, and a change in the size of flicker (flicker) during driving.

When it uses for the liquid crystal display element of such a transverse electric field system, it is excellent in voltage retention and it is a liquid crystal aligning agent which reduced charge accumulation|storage, In patent document 1, the liquid-crystal orientation containing specific diamine and an aliphatic tetracarboxylic-acid derivative|guide_body I am disclosed However, with performance improvement of a liquid crystal display element, the characteristic calculated|required of a liquid crystal aligning film is also becoming strict, and it is difficult to fully satisfy|fill all the requested|required characteristics by these conventional techniques.

International Publication No. WO2004/021076 pamphlet

The present invention is to provide a liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element that can obtain a liquid crystal aligning film excellent in voltage retention, rapid relaxation of accumulated charge, and less likely to generate flicker (flicker) during driving make it a task

As a result of these inventors earnestly examining in order to solve the said subject, they discovered that various characteristics were improved simultaneously by introduce|transducing a specific structure in the polymer contained in a liquid crystal aligning agent, and completed this invention.

This invention is based on this knowledge, and makes the following summary.

1. The polymer obtained from diamine which has a structure shown by following formula (1), and organic solvent are contained, The liquid crystal aligning agent characterized by the above-mentioned.

[Formula 1]

(In formula (1), R ¹ and R ² are a hydrogen atom or a monovalent organic group. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group. * represents a bonding site.)

2. At least 1 sort(s) of polymer chosen from the group which consists of the polyimide which is the polyimide precursor which is a polycondensate of the diamine and tetracarboxylic dianhydride which have the structure shown by the said polymer by said Formula (1), and its imidated substance. The liquid crystal aligning agent of said 1 which is phosphorus.

3. Liquid crystal aligning agent of said 1 or 2 in which said diamine is represented by following formula (2).

[Formula 2]

(In formula (2), the definitions of R ¹ and R ² are the same as those of the formula (1) above, each of R ³ independently represents a single bond or a structure of the following formula (3), and n is 1 to 3 represents an integer of. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group.)

[Formula 3]

(in formula (3), R ⁴ is a single bond, -O-, -COO-, -OCO-, -(CH ₂ ) _l -, -O(CH ₂ ) _m O-, -CONH-, and - represents a divalent organic group selected from NHCO- (l, m represents an integer of 1 to 5), * ₁ represents a site bonding to the benzene ring in formula (2), * ₂ represents an amino group in formula (2) indicates the site where it binds.)

4. The liquid crystal aligning agent of said 1-3 in which the said polyimide precursor has a structure represented by following formula (4).

[Formula 4]

(In the formula (4), X ₁ is a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ₁ is a divalent organic group derived from the diamine represented by the formula (1), and R ₅ is a hydrogen atom or It is an alkyl group having 1 to 5 carbon atoms.)

5. Liquid crystal aligning agent as described in said 4 which is at least 1 sort(s) chosen from the group which consists of a structure 5. X< ₁ > is represented by following (A-1) - (A-21) in said Formula (6).

6. The liquid crystal aligning agent of said 4 or 5 in which the polymer which has a structural unit represented by said Formula (4) contains 10 mol% or more with respect to all the polymers contained in a liquid crystal aligning agent.

7. The said organic solvent contains at least 1 sort(s) selected from the group which consists of 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, The said 1st term in any one of 1-6. liquid crystal aligning agent.

8. The liquid crystal aligning film obtained using the liquid crystal aligning agent in any 1 of said 1-7.

9. A liquid crystal display element provided with the liquid crystal aligning film of said 8.

10. The liquid crystal display element according to 9 above, wherein the liquid crystal display element is a transverse electric field drive system.

11. At least 1 sort(s) of polymer chosen from the group which consists of a polyimide precursor which is a polycondensate of the diamine which has a structure represented by following formula (1), and tetracarboxylic dianhydride, and the polyimide which is its imidated product.

[Formula 5]

(In formula (1), R ¹ and R ² are a hydrogen atom or a monovalent organic group. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group. * represents a bonding site.)

12. The polymer according to 11 above, wherein the diamine is represented by the following formula (2).

[Formula 6]

(In formula (2), the definitions of R ¹ and R ² are the same as those of the formula (1), R ³ each independently has a single bond or a structure represented by the following formula (3), and n is 1 to An integer of 3. Any hydrogen atom of the benzene ring may be substituted with a monovalent organic group.)

[Formula 7]

(in formula (3), R ⁴ is a single bond, -O-, -COO-, -OCO-, -(CH ₂ ) _l -, -O(CH ₂ ) _m O-, -CONH-, and - represents a divalent organic group selected from NHCO- (l, m represents an integer of 1 to 5), * ₁ represents a site bonding to the benzene ring in formula (2), * ₂ represents an amino group in formula (2) indicates the site where it binds.)

[Formula 8]

(In the formula (4), X ₁ is a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ₁ is a divalent organic group derived from the diamine represented by the formula (1), and R ₅ is a hydrogen atom or It is an alkyl group having 1 to 5 carbon atoms.)

14. The polymer according to 13 above, wherein in the above formula (6), X ₁ is at least one selected from the group consisting of structures represented by the following (A-1) to (A-21).

15. Diamine represented by the following formula (2).

[Formula 9]

(In formula (2), the definitions of R ¹ and R ² are the same as those of the formula (1), R ³ each independently has a single bond or a structure represented by the following formula (3), and n is 1 to An integer of 3. Any hydrogen atom of the benzene ring may be substituted with a monovalent organic group.)

According to use of the liquid crystal aligning agent of this invention, relaxation|moderation of an accumulation|storage electric charge is quick, and the liquid crystal display element excellent in the liquid crystal aligning film and display characteristic in which a flicker (flicker) does not generate|occur|produce easily during drive is provided.

Although it is not certain how the said subject can be solved by this invention, it is generally thought as follows. The diamine represented by said (1) which the polymer contained in the liquid crystal aligning agent of this invention has has a structure in which a conductive pyrrole ring and a benzene ring are conjugated, In the liquid crystal aligning film formed by such a liquid crystal aligning agent, the sphere of an element At the same time, it is considered that the transfer of the applied electric charge is facilitated, and the relaxation of the accumulated electric charge can be promoted, and the like.

<specific diamine>

The liquid crystal aligning agent of this invention contains the polymer obtained from the diamine (in this invention, it is also called specific diamine) which has a structure of following formula (1).

[Formula 10]

In the formula (1), R ¹ and R ² are as defined above. Among them, R ¹ and R ² are preferably an alkyl group, alkenyl group, alkoxy group, fluoroalkyl group, fluoroalkenyl group, or fluoroalkoxy group having 1 to 3 carbon atoms, in particular, a hydrogen atom or a methyl group desirable. In addition, * represents the site|part couple|bonded with an amino group, a substituted amino group, another organic group, etc.

In a specific diamine, as shown in the following formula (1-1), the bonding position of two benzene rings to the pyrrole ring is from the point of charge transfer, and at least one of them is a carbon next to the nitrogen atom on the pyrrole ring. It is preferable to couple|bond with an atom.

[Formula 11]

The said specific diamine can be represented by following formula (1-2), for example, and especially the diamine represented by following formula (1-3) is preferable, Furthermore, the diamine represented by Formula (1-4) is more preferably. In these formulas, * represents a binding site.

[Formula 12]

In Formulas (1-2) to (1-4), the definitions of R ¹ and R ² are the same as in the case of Formula (1), and Q ¹ and Q ² are each independently a single bond or 2 It is a valent organic group, ie, Q ¹ and Q ² may have structures different from each other. In addition, a mutually different structure may be sufficient as ^two Q2 in Formula (1-4). In addition, the arbitrary hydrogen atoms of a benzene ring may be substituted by the monovalent organic group similarly to the case of said Formula (1).

As a preferable example of the said specific diamine, the diamine represented by following formula (2) is mentioned, More preferably, it is the diamine represented by Formula (2-1).

[Formula 13]

In formula (2), the definitions of R ¹ and R ² are the same as those of the formula (1), R ³ each independently represents a single bond or a structure of the following formula (3), and n is 1-3 represents an integer. The arbitrary hydrogen atoms of a benzene ring may be substituted by the monovalent organic group.

[Formula 14]

(in formula (3), R ⁴ is a single bond, -O-, -COO-, -OCO-, -(CH ₂ ) _l -, -O(CH ₂ ) _m O-, -CONH-, and - represents a divalent organic group selected from NHCO- (l, m represents an integer of 1 to 5), * ₁ represents a site bonding to the benzene ring in formula (2), * ₂ represents an amino group in formula (2) indicates the site where it binds.)

In Formula (2) and Formula (2-1), n represents the integer of 1-3. Preferably it is 1 or 2.

Although the following can be illustrated as a specific example of the diamine of said Formula (2), it is not limited to these. Among them, (2-1-1), (2-1-2), (2-1-3), (2-1-4), (2-1-5) , (2-1-8), (2-1-9), (2-1-10), (2-1-11) or (2-1-12) is preferable, and (2-1-1) ), (2-1-2), (2-1-3), (2-1-4), (2-1-5), (2-1-11) or (2-1-12) Especially preferred.

[Formula 15]

<Synthesis method of specific diamine>

Although the method to synthesize|combine the specific diamine of this invention is not specifically limited, For example, the method of synthesize|combining the dinitro compound represented by following formula (1), reducing a nitro group and converting into an amino group is mentioned.

[Formula 16]

(R ₁ , R ₂ and R ₃ represent hydrogen or a monovalent organic group.)

The catalyst used for such a reduction reaction is preferably an activated carbon-supporting metal available as a commercially available product, and examples thereof include palladium-activated carbon, platinum-activated carbon, and rhodium-activated carbon. The catalyst may not necessarily be an activated carbon-supported metal catalyst such as palladium hydroxide, platinum oxide, or Raney nickel. In particular, palladium-activated carbon is preferable because good results are obtained.

In order to advance the reduction reaction more effectively, the reaction may be carried out in the presence of activated carbon. At this time, although the quantity of the activated carbon to be used is not specifically limited, The range of 1-30 mass % is preferable with respect to a dinitro compound, and its 10-20 mass % is more preferable. For the same reason, the reaction may be carried out under pressure. In this case, in order to avoid reduction of a benzene nucleus, it is preferable to carry out in the pressurization range of up to 20 atm, and it is more preferable to carry out in the pressurization range of up to 10 atm.

The solvent can be used without limitation as long as it is a solvent that does not react with each raw material. For example, aprotic polar organic solvents (DMF, DMSO, DMAc, NMP, etc.); ethers (Et ₂ O, i-Pr ₂ O, TBME, CPME, THF, dioxane, etc.); aliphatic hydrocarbons (pentane, hexane, heptane, petroleum ether, etc.); aromatic hydrocarbons (benzene, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, nitrobenzene, tetralin, etc.); halogen-based hydrocarbons (chloroform, dichloromethane, carbon tetrachloride, dichloroethane, etc.); lower fatty acid esters (methyl acetate, ethyl acetate, butyl acetate, methyl propionate, etc.); nitriles (acetonitrile, propionitrile, butyronitrile, etc.); etc. can be used. These solvents can be suitably selected in consideration of the easiness of reaction, etc., and can also be used in mixture of 2 or more types. If necessary, the solvent may be dried using an appropriate dehydrating agent or desiccant and used as a non-aqueous solvent.

0.1-10 mass times is preferable with respect to a dinitro compound, and, as for the usage-amount (reaction concentration) of a solvent, 0.5-30 mass times is more preferable, 1-10 mass times is especially preferable. Although the reaction temperature is not specifically limited, It is the range from -100 degreeC to the boiling point of the solvent to be used, Preferably, it is -50-150 degreeC. Reaction time is 0.05 to 350 hours normally, Preferably it is 0.5 to 100 hours.

On the other hand, the method for synthesizing the nitro compound (A-1) is not particularly limited, but when the amino group of the compound (A-1) is substituted at the 2-position and the 4-position, for example, the following formula (A-2 It can be obtained by reacting a diamine represented by ) with an aryl halide having a nitro group in the presence of a base and optionally in the presence of an additive (X represents F, Cl, Br, I, or OTf).

[Formula 17]

In the aryl halide having a nitro group, when X is F or Cl and the NO ₂ group is at the 2-position or 4-position with respect to X, the compound ( A-1) can be obtained. The base to be used is, for example, an inorganic base such as sodium hydrogen carbonate, potassium hydrogen carbonate, potassium phosphate, sodium carbonate, potassium carbonate, lithium carbonate, cesium carbonate, trimethylamine, triethylamine, tripropylamine, triisopropylamine , amines such as tributylamine, diisopropylethylamine, pyridine, quinoline and collidine, sodium hydride, potassium hydride, and the like can be used. The reaction solvent and reaction temperature are in accordance with the above description. The product may be purified by recrystallization, distillation, silica gel column chromatography, or the like.

When X is Br or I, the NO ₂ group may be in the 2-position, 3-position, or 4-position with respect to X, and a dinitro body can also be obtained by using a CN cross-coupling reaction in the presence of a suitable metal catalyst, ligand, or base. can be obtained Examples of the metal catalyst include palladium acetate, palladium chloride, palladium chloride-acetonitrile complex, palladium-activated carbon, bis(dibenzylideneacetone)palladium, tris(dibenzylideneacetone)dipalladium, bis(acetonitrile)dichloropalladium, Bis(benzonitrile)dichloropalladium, CuCl, CuBr, CuI, CuCN, etc., but are not limited thereto. Examples of ligands include triphenylphosphine, tri-o-tolylphosphine, diphenylmethylphosphine, phenyldimethylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenyl Phosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,1'-bis(diphenylphosphino)ferrocene, trimethylphosphite, triethylphosphite, triphenylphosphite, tri-tert- Butylphosphine etc. are mentioned, However, It is not limited to these. As an example of the base, the above-mentioned base may be used. The reaction solvent and reaction temperature are in accordance with the above description. The product may be purified by recrystallization, distillation, silica gel column chromatography, or the like.

In addition, there is no restriction|limiting in particular in the method of synthesizing a compound (A-2), For example, a method of synthesizing a diamine represented by the following formula (A-3) and introducing R ₁ , R ₃ into an NH ₂ group can be heard

[Formula 18]

In introducing R ₁ and R ₃ , any compound capable of reacting with amines is sufficient, for example, acid halides, acid anhydrides, isocyanates, epoxies, oxetanes, aryl halide, and alkyl halide. can Moreover, alcohol etc. which substituted the hydroxyl group of alcohol with leaving groups, such as OMs, OTf, OTs, can be used.

Although there is no restriction|limiting in particular in the method of introduce|transducing the monovalent organic group which consists of R< ₁ > and R< ₃ > into _the NH2 group, The method of making an acid halide react in presence of a suitable base is mentioned. Examples of the acid halide include acetyl chloride, propionic acid chloride, methyl chloroformate, ethyl chloroformate, chloroformate n-propyl, chloroformate i-propyl, chloroformate n-butyl, chloroformate i-butyl, chloroformate t-butyl, Benzyl chloroformate and 9-fluorenyl chloroformate are mentioned. As an example of the base, the above-mentioned base may be used. The reaction solvent and reaction temperature are in accordance with the above description.

R ₁ , R ₃ may be introduced by reacting the NH ₂ group with an acid anhydride. Examples of the acid anhydride include acetic anhydride, propionic acid anhydride, dimethyl dicarbonate, diethyl bicarbonate, di-tert-butyl dicarbonate, and dibenzyl dicarbonate. In order to accelerate the reaction, a catalyst may be used, or pyridine, collidine, N,N-dimethyl-4-aminopyridine, or the like may be used. The amount of the catalyst is preferably 0.0001 to 1 mol with respect to the usage-amount of (A-3). The reaction solvent and reaction temperature are in accordance with the above description.

You may introduce R _{<1 >} by making isocyanates react with NH2 group. Methyl isocyanate, ethyl isocyanate, n-propyl isocyanate, phenyl isocyanate etc. are mentioned as an example of isocyanate. The reaction solvent and reaction temperature are in accordance with the above description.

Epoxy compounds or oxetane compounds may be reacted with NH ₂ group to introduce R ₁ and R ₃ . Ethylene oxide, propylene oxide, 1,2-butyrene oxide, trimethylene oxide etc. are mentioned as an example of epoxies and oxetanes. The reaction solvent and reaction temperature are in accordance with the above description.

R ₁ and R ₃ may be introduced by reacting the NH ₂ group with an alcohol in which the hydroxyl group of the alcohol is substituted with a leaving group such as OMs, OTf, or OTs in the presence of a suitable base. Examples of alcohols include methanol, ethanol, 1-propanol, and the like. By reacting these alcohols with methanesulfonyl chloride, trifluoromethanesulfonyl chloride, paratoluenesulfonic acid chloride, etc., OMs, OTf, An alcohol substituted with a leaving group such as OTs can be obtained. As an example of the base, the above-mentioned base may be used. The reaction solvent and reaction temperature are in accordance with the above description.

R ₁ and R ₃ may be introduced by reacting the NH ₂ group with an alkyl halide in the presence of an appropriate base. Examples of the alkyl halide include methyl iodide, ethyl iodide, n-propyl iodide, methyl bromide, ethyl bromide, and n-propyl bromide. Examples of the base include, in addition to the above-mentioned base, metal alkoxides such as potassium-tert-butoxide and sodium-tert-butoxide. The reaction solvent and reaction temperature are in accordance with the above description.

In addition, there is no particular limitation on the method for synthesizing compound (A-3), and examples include a method of synthesizing a nitro compound represented by the following formula (4) and reducing the nitro group of the nitro compound to convert it to an amino group. .

[Formula 19]

The catalyst, solvent, and temperature used for the reaction are in accordance with the above description.

In addition, although there is no restriction|limiting in particular in the method of synthesizing compound (A-4), The 1, 4-diketone compound (A-5) represented by following formula (5) and a primary amine are dehydrated and condensed under acidic conditions. can be synthesized.

[Formula 20]

Examples of the acid used in the reaction include, but are not limited to, acetic acid, p-toluenesulfonic acid, pyridinium p-toluenesulfonic acid, and the like. The reaction solvent and reaction temperature are in accordance with the above description.

In addition, although there is no particular limitation on the method for synthesizing compound (A-5), it can be obtained by reacting an α-haloketone having a nitro group represented by the following formula (6) with a ketone having a nitro group in the presence of a base.

(X represents Br, I or OTf.)

[Formula 21]

As an example of the base used in the reaction, the above-mentioned base may be used. The reaction solvent and reaction temperature are in accordance with the above description. Additives may be used for the purpose of accelerating the reaction rate. Although zinc chloride, sodium iodide, potassium iodide, tetrabutylammonium iodide, etc. can be used as the said additive, it is not limited to these.

<Specific Polymer>

The polymer of this invention is a polymer obtained using the said specific diamine. Specific examples include polyamic acid, polyamic acid ester, polyimide, polyurea, polyamide, and the like. Especially, from a viewpoint of use as a liquid crystal aligning agent, the polyimide precursor containing the structural unit represented by following formula (4), and at least 1 sort(s) of polymer chosen from the polyimide which is its imidate (hereinafter also referred to as a specific polymer) ) is more preferable.

[Formula 22]

In the formula (4), X ₁ is a tetravalent organic group derived from a tetracarboxylic acid derivative, and Y ₁ is a divalent organic group derived from a specific diamine. R ₅ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R ₅ is preferably a hydrogen atom, a methyl group, or an ethyl group from the viewpoint of easiness of imidation by heating.

Said X ₁ is suitably selected according to the degree of characteristics required, such as the solubility with respect to the solvent of a polymer, the applicability|paintability of a liquid crystal aligning agent, the orientation of the liquid crystal in the case of setting it as a liquid crystal aligning film, voltage retention, accumulated electric charge, Two or more types may be sufficient in the same polymer.

If the specific example of X< ₁ > is shown, the structure etc. of Formula (X-1) - (X-46) which are published on page 13 - page 14 of International Publication 2015/119168 will be mentioned.

Although (A-1) - (A-21) which are preferable X< ₁ > are shown below, it is not limited to these.

[Formula 23]

[Formula 24]

Among the above, (A-1) and (A-2) are particularly preferable from the viewpoint of further improvement in rubbing resistance, (A-4) is particularly preferable from the viewpoint of further improvement of the relaxation rate of the accumulated charge, (A) -15) - (A-17) etc. are especially preferable from a viewpoint of the further improvement of the liquid-crystal orientation and the relaxation rate of an accumulation|storage charge.

<Other structural units>

In addition to the structural unit represented by Formula (4), the said polyimide precursor may have a structural unit represented by following formula (5).

[Formula 25]

In Formula ( ₅ ), X2 is the same as the definition in said Formula (4). As a specific example of X< ₂ >, what was illustrated by X< ₁ > of Formula (4) including a preferable example is mentioned. All of R ₄ are the same as defined in the formula (4). It is preferable that at least one of two R ₄ is a hydrogen atom.

In addition, Y2 is a _divalent organic group derived from the diamine which does not contain the structure shown by said Formula (1) in a principal chain direction, The structure is not specifically limited. Y ₂ is suitably selected according to the degree of properties required, such as solubility in the solvent of a polymer, applicability|paintability of a liquid crystal aligning agent, the orientation of a liquid crystal in the case of setting it as a liquid crystal aligning film, voltage retention, accumulated electric charge, etc., and the same polymer Two or more types may be mixed in it.

If specific examples of Y ₂ are shown, the structure of formula (2) published on page 4 of International Publication No. 2015/119168, and formulas (Y-1) to (Y-97), which are published on pages 8 to 12, , a structure of (Y-101) to (Y-118); A divalent organic group published on page 6 of International Publication No. 2013/008906, obtained by removing two amino groups from Formula (2); A divalent organic group obtained by removing two amino groups from Formula (1) published on page 8 of International Publication No. 2015/122413; The structure of formula (3) published on page 8 of International Publication No. 2015/060360; A divalent organic group in which two amino groups were removed from Formula (1) described on page 8 of JP 2012-173514 ; The divalent organic group etc. which removed two amino groups from Formula (A) - (F) published on the 9th page of international publication 2010-050523 are mentioned.

_Although the structure of preferable Y2 is shown below, this invention is not limited to these.

[Formula 26]

[Formula 27]

[Formula 28]

[Formula 29]

In said structure, (B-28), (B-29) etc. are especially preferable from a viewpoint of the further improvement of rubbing resistance, (B-1) - (B-3) etc. are further improvement of liquid-crystal orientation Particularly preferred from the viewpoint of It is preferable from the viewpoint of further improvement of voltage retention.

When the said polyimide precursor contains the structural unit represented by Formula (5) other than the structural unit represented by Formula (4), the structural unit represented by Formula (4) is the sum total of Formula (4) and Formula (5) It is preferably 10 mol% or more, more preferably 20 mol% or more, and particularly preferably 30 mol% or more.

As for the molecular weight of the polyimide precursor used for this invention, 2,000-500,000 are preferable at a weight average molecular weight, More preferably, it is 5,000-300,000, More preferably, it is 10,000-100,000.

<Polyimide>

Among specific polymers, the polyimide is obtained by ring-closing the polyimide precursor represented by Formula (4) and Formula (5). The imidation ratio in this case does not necessarily need to be 100 %, It can adjust arbitrarily according to a use and objective.

As a method of imidating a polyimide precursor, a known method can be used. Chemical imidation of adding a basic catalyst to the solution of the polyimide precursor is simple. Chemical imidization is preferable because the imidation reaction proceeds at a relatively low temperature and the molecular weight reduction of the polymer does not easily occur during the imidization process.

Chemical imidation can be performed by stirring a polyimide precursor in basic catalyst presence in an organic solvent. As an organic solvent, the solvent used at the time of the polymerization reaction mentioned above can be used. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, triethylamine is preferable because it has sufficient basicity to advance the reaction.

The temperature at the time of imidation reaction is -20-140 degreeC, Preferably it is 0-100 degreeC, Preferably the reaction time can be performed in 1-100 hours. The quantity of a basic catalyst is 0.5-30 mole times of an amic acid ester group, Preferably it is 2-20 mole times. The imidation rate of the polymer obtained is controllable by adjusting a catalyst amount, temperature, reaction time, etc.

Since the catalyst etc. which were added remain|survive in the solution after imidation reaction of a polyimide precursor, the obtained imidation polymer is collect|recovered by the means described below, it melt|dissolves again in an organic solvent, and it is liquid crystal aligning agent of this invention It is preferable to do

That is, a polymer can be deposited by injecting|pouring into a poor solvent, stirring well the solution of the polyimide obtained by making it above. Precipitation is performed several times, and after washing|cleaning with a poor solvent, it is made to room temperature or heat-drying, and the refined|purified polyimide powder can be obtained.

Although it does not specifically limit as a poor solvent, Methanol, acetone, hexane, a butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, etc. are mentioned.

<Liquid crystal aligning agent>

Although the liquid crystal aligning agent of this invention contains a specific polymer, the limit which exhibits the effect as described in this invention WHEREIN: You may contain 2 or more types of specific polymers of a different structure. Moreover, in addition to a specific polymer, you may contain another polymer. Examples of other polymers include polyamic acid, polyimide, polyamic acid ester, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene or a derivative thereof, and poly(styrene-phenylmaleimide). ) derivatives, poly(meth)acrylates, and the like. Moreover, you may contain the polyimide etc. chosen from the polyimide which imidated the polyimide precursor represented by said Formula (5), and this polyimide precursor.

When the liquid crystal aligning agent of this invention contains another polymer, as for the ratio of the specific polymer with respect to all the polymer components, 5 mass % or more is preferable, More preferably, 5-95 mass % is mentioned.

A liquid crystal aligning agent is used in order to produce a liquid crystal aligning film, From a viewpoint of forming a uniform thin film, it generally takes the form of a coating liquid. Also in the liquid crystal aligning agent of this invention, it is preferable that it is an above-described polymer component and it is preferable that it is a coating liquid containing the organic solvent in which this polymer component is dissolved. In that case, the density|concentration of the polymer in a liquid crystal aligning agent can be suitably changed by setting of the thickness of the coating film which you want to form. It is preferable that it is 1 mass % or more from the point of forming a uniform and defect-free coating film, and it is preferable to set it as 10 mass % or less from the point of storage stability of a solution. A particularly preferable concentration of the polymer is 2 to 8% by mass.

The organic solvent contained in a liquid crystal aligning agent will not be specifically limited if a polymer component melt|dissolves uniformly. Specific examples thereof include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyro Lactone, 1, 3- dimethyl imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, etc. are mentioned. Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, or γ-butyrolactone is preferable.

In addition, it is common to use the mixed solvent which used the organic solvent contained in a liquid crystal aligning agent together with the solvent which improves the applicability|paintability at the time of apply|coating a liquid crystal aligning agent, and the surface smoothness of a coating film in addition to the above solvents, Also in the liquid crystal aligning agent of this invention, such a mixed solvent is used preferably. Although the specific example of the organic solvent used together is given below, it is not limited to these examples.

For example, ethanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, Isopentyl alcohol, tert-pentyl alcohol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-ethyl-1- Butanol, 1-heptanol, 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol, 1-methylcyclohexanol, 2-methyl Cyclohexanol, 3-methylcyclohexanol, 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, dipropyl ether, dibutyl ether, dihexyl ether, dioxane, Ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-penta Non, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 2-pentanone, 3-pentanone, 2-hexanone, 2-heptanone, 4-heptanone, 3-ethoxybutyl acetate, 1- Methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, 2-(methoxymethoxy) ethanol, ethylene glycol monobutyl ether, ethylene glycol Monoisoamyl ether, ethylene glycol monohexyl ether, 2-(hexyloxy) ethanol, furfuryl alcohol, diethylene glycol, propylene glycol, propylene glycol monobutyl ether, 1-(butoxyethoxy) propanol, propylene glycol mono Methyl ether acetate, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene Glycol monobutyl ether acetate, ethylene glycol monoacetate, ethylene glycol diacetate , Diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy) ethyl acetate, diethylene glycol acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monomethyl ether Ethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, 3- Ethyl methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid propyl, 3-methoxybutyl propionate, methyl lactate ester, lactic acid ethyl ester, lactic acid n-propyl ester, lactic acid n-butyl ester , lactic acid isoamyl ester, a solvent represented by the following formulas [D-1] to [D-3], and the like.

[Formula 30]

In formula [D- ¹ ], D1 represents a C1-C3 alkyl group, in formula [D- ² ], D2 represents a C1-C3 alkyl group, In formula [D- ³ ], D3 represents a C1-C4 alkyl group. Among them, 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2- Pentanone, ethylene glycol monobutyl ether or dipropylene glycol dimethyl ether is preferable. The kind and content of such a solvent are suitably selected according to the coating apparatus of a liquid crystal aligning agent, application|coating conditions, application|coating environment, etc.

The liquid crystal aligning agent of this invention may contain components other than a polymer component and an organic solvent further. Such additional components include an adhesion aid for increasing the adhesion between the liquid crystal aligning film and the substrate or the adhesion between the liquid crystal aligning film and the sealing material, a crosslinking agent for increasing the strength of the liquid crystal aligning film, a dielectric or conductive material for adjusting the dielectric constant or electrical resistance of the liquid crystal aligning film and the like. Specific examples of these additional components are as variously disclosed in the known literature related to the liquid crystal aligning agent, but if the example is shown, on pages 53 to 55 of International Publication No. 2015/060357 The disclosed component etc. are mentioned.

<Liquid crystal alignment film>

The liquid crystal aligning film of this invention is obtained from the said liquid crystal aligning agent of this invention. For an example of a method of obtaining a liquid crystal aligning film from a liquid crystal aligning agent, a liquid crystal aligning agent in the form of a coating liquid is applied to a substrate, dried, and a method of performing alignment treatment with a rubbing treatment method or a photo-alignment treatment method for a film obtained by firing can be heard

It will not specifically limit if it is a board|substrate with high transparency as a board|substrate which apply|coats a liquid crystal aligning agent, Plastic substrates, such as an acryl board|substrate and a polycarbonate board|substrate, etc. can also be used with a glass substrate and a silicon nitride board|substrate. In that case, it is preferable from the point of simplification of a process to use the board|substrate with which the ITO electrode etc. for driving a liquid crystal were formed. In the reflective liquid crystal display element, an opaque material such as a silicon wafer can be used as long as it is only a one-side substrate, and a material that reflects light such as aluminum can also be used for the electrode in this case.

Although the application method of a liquid crystal aligning agent is not specifically limited, Industrially, screen printing, offset printing, flexographic printing, the inkjet method, etc. are common. As another coating method, there exist a dip method, the roll coater method, the slit coater method, the spinner method, the spray method, etc., You may use these according to the objective.

After apply|coating a liquid crystal aligning agent on a board|substrate, a solvent is evaporated with heating means, such as a hotplate, heat circulation type oven, IR (infrared) type|mold oven, and it bakes. Drying after apply|coating a liquid crystal aligning agent, and a baking process can select arbitrary temperature and time. Usually, in order to fully remove the solvent to contain, it bakes at 50-120 degreeC for 1 to 10 minutes, and then, conditions to bake at 150-300 degreeC for 5 to 120 minutes are mentioned.

Although the thickness of the liquid crystal aligning film after baking is not specifically limited, Since reliability of a liquid crystal display element may fall when too thin, it is preferable that it is 5-300 nm, and 10-200 nm is more preferable.

The liquid crystal aligning film of this invention is preferable as a liquid crystal aligning film of the liquid crystal display element of transverse electric field systems, such as an IPS system and an FFS system, and is especially useful as a liquid crystal aligning film of the liquid crystal display element of an FFS system.

<Liquid crystal display element>

After obtaining the board|substrate with the liquid crystal aligning film obtained from the said liquid crystal aligning agent, the liquid crystal display element of this invention produces a liquid crystal cell by a known method, and sets it as an element using the liquid crystal cell.

As an example of the manufacturing method of a liquid crystal cell, the liquid crystal display element of a passive matrix structure is taken as an example and demonstrated. Moreover, the liquid crystal display element of the active matrix structure in which switching elements, such as TFT (Thin Film Transistor), were formed in each pixel part which comprises an image display may be sufficient.

Specifically, a transparent glass substrate is prepared, a common electrode is formed on one substrate, and a segment electrode is formed on the other substrate. These electrodes can be set as, for example, an ITO electrode, and are patterned so that a desired image display may be performed. Next, an insulating film is formed on each substrate so as to cover the common electrode and the segment electrode. The insulating film can be, for example, a film made of SiO ₂ -TiO ₂ formed by a sol-gel method. Next, a liquid crystal alignment film is formed on each substrate under the same conditions as described above.

Next, after arrange|positioning an ultraviolet curable sealing material in the predetermined place on one board|substrate among the board|substrates of 2 sheets in which the liquid crystal aligning film was formed, and also arrange|positioning a liquid crystal in predetermined several places on the liquid crystal aligning film surface, liquid crystal A liquid crystal cell is obtained by irradiating an ultraviolet-ray to the whole surface of a board|substrate and hardening a sealing material, after a liquid crystal is pressed to the whole surface of a liquid crystal aligning film by bonding and crimping|bonding the other board|substrate so that an alignment film may oppose.

Or as a process after forming a liquid crystal aligning film on a board|substrate, when arranging a sealing material in a predetermined place on one board|substrate, after forming the opening part which can be filled with a liquid crystal from the outside, and bonding a board|substrate together without arrange|positioning a liquid crystal , the liquid crystal material is injected into the liquid crystal cell through the opening formed in the sealing material, and the opening is then sealed with an adhesive to obtain a liquid crystal cell. A vacuum injection method may be sufficient for injection|pouring of a liquid crystal material, and the method using capillary phenomenon in air|atmosphere may be sufficient.

In any of the above methods, in order to secure the space in which the liquid crystal material is filled in the liquid crystal cell, columnar projections are formed on one substrate, the spacers are dispersed on the one substrate, or the spacers are mixed in the sealing material. Or, it is preferable to take measures such as a combination of these.

As said liquid crystal material, a nematic liquid crystal and a smectic liquid crystal are mentioned, Among them, a nematic liquid crystal is preferable, and either a positive liquid crystal material and a negative liquid crystal material may be used. Next, a polarizing plate is installed. Specifically, it is preferable to affix a pair of polarizing plates to the surface on the opposite side to the liquid-crystal layer of 2 board|substrates.

In addition, the liquid crystal aligning film and liquid crystal display element of this invention are not limited to said base material as long as the liquid crystal aligning agent of this invention is used, What was produced by other well-known methods may be sufficient. The process until obtaining a liquid crystal display element from a liquid crystal aligning agent is disclosed in Paragraph 0074 of page 17 of Unexamined-Japanese-Patent No. 2015-135393 - Paragraph 0081 of page 19, etc., for example.

Example

Hereinafter, the present invention will be specifically described with reference to Examples and the like. In addition, the analysis of this invention is not limited to these Examples.

The abbreviation of the raw material in the following and the characteristic evaluation method are as follows.

[Formula 31]

[Formula 32]

<Organic solvent>

NMP: N-methyl-2-pyrrolidone,

NEP: N-ethyl-2-pyrrolidone

GBL: γ-butyrolactone, BCS: butyl cellosolve

PB: propylene glycol monobutyl ether

DME: dipropylene glycol dimethyl ether

DAA: 4-hydroxy-4-methyl-2-pentanone

DEDG: Diethylene glycol diethyl ether

DIBK: 2,6-dimethyl-4-heptanone;

DIPE: diisopropyl ether,

DIBC: 2,6-dimethyl-4-heptanol;

Pd/C: palladium carbon,

DMSO: dimethyl sulfoxide, THF: tetrahydrofuran

<Additives>

LS-4668: 3-glycidoxypropyltriethoxysilane

<crosslinking agent>

[Formula 33]

In addition, in the specification, Boc and Fmoc represent groups shown below, and Me represents a methyl group.

[Formula 34]

(Measurement of ¹ H-NMR)

Apparatus: Varian NMR system 400NB (400 MHz) (manufactured by Varian), and JMTC-500/54/SS (500 MHz) (manufactured by JEOL)

Measurement solvent: CDCl ₃ (deuterated chloroform), DMSO-d ₆ (deuterated dimethyl sulfoxide)

Reference material: TMS (tetramethylsilane) (δ: 0.0 ppm, ¹ H) and CDCl ₃ (δ: 77.0 ppm, ¹³ C)

(Measurement of imidization rate)

20 mg of polyimide powder was placed in an NMR sample tube (NMR sampling tube standard, φ5 (manufactured by Kusano Scientific)), and deuterated dimethyl sulfoxide (DMSO-d6, 0.05% TMS (tetramethylsilane) mixture) (0.53 ml) was added, and ultrasonic wave was applied to completely dissolve it. Proton NMR of 500 MHz was measured for this solution with the NMR measuring instrument (JNW-ECA500, the Nippon Electronics Datum company make). The imidation rate is determined by determining a proton derived from a structure that does not change before and after imidization as a reference proton, and the integrated peak of this proton and the proton peak derived from the NH group of the amic acid appearing around 9.5 ppm to 10.0 ppm. It calculated|required by the following formula using the value.

Imidization rate (%) = (1 - α·x/y) × 100

In the above formula, x is the integrated value of the proton peak derived from the NH group of the amic acid, y is the integrated peak of the reference proton, and α is the NH of the amic acid in the case of polyamic acid (imidization rate is 0%) It is the ratio of the number of reference protons to one original proton.

<Synthesis of diamine compound (DA-1)>

[Formula 35]

Zinc chloride (120.3 g, 882 mmol) was added to a 3 L (liter) four-necked flask, and it heated up to 100 degreeC, and vacuum-dried with the oil pump for 1 hour. Then, at room temperature under a nitrogen atmosphere, toluene (460 g), diethylamine (45.0 g, 615 mmol), t-butanol (46.4 g, 626 mmol), 2-bromo-4-nitroacetophenone (100.0 g, 410 mmol), and 4-nitroacetophenone (104.2 g, 631 mmol) were sequentially added, and the mixture was stirred at room temperature for 3 days. After confirming completion|finish of reaction by HPLC (high-performance liquid chromatography), 5% sulfuric acid aqueous solution (400g) was added, it neutralized, and it stirred at room temperature for 1 hour. The precipitated crystals were filtered under reduced pressure, washed sequentially with toluene (200 g), pure water (300 g), and methanol (200 g), and then dried to obtain crude crystals. The obtained crude crystals were completely dissolved in tetrahydrofuran (1340 g) at 60°C, and ethanol (1340 g) was added thereto, followed by stirring at 5°C for 1 hour. The precipitated crystals were filtered under reduced pressure, washed with ethanol (200 g), and then dried to obtain powder crystals (1) (amount 63 g, yield 45%).

[Formula 36]

Compound (1) (65.8 g, 200 mmol), ammonium acetate (84.5 g, 1100 mmol), and acetic acid (855 g) were poured into a 2 L four-necked flask, and the temperature was raised to 120° C., and 3 under reflux time was stirred. After confirming the completion of the reaction by HPLC (high performance liquid chromatography), the reaction liquid was added to cold water (4000 g) and stirred for 1 hour. The precipitated crystals were filtered under reduced pressure, repulp washed with acetonitrile (100 g), and dried to obtain powder crystals (2) (amount 53 g, yield 78%).

[Formula 37]

Compound (2) (41.3 g, 134 mmol), potassium carbonate (27.8 g, 201 mmol), and dimethylformamide (540 g) were charged in a 1 L four-necked flask, and methyl iodide (38.1 g) at room temperature , 268 mmol) was added dropwise and stirred for 24 hours. After confirming completion of the reaction by HPLC (high-performance liquid chromatography), the reaction liquid was added to cold water (4300 g) and stirred for 1 hour. The precipitated crystals were filtered under reduced pressure, washed with 2-propanol (100 g), and then dried to obtain powder crystals (3) (amount 41.1 g, yield 90%).

[Formula 38]

A mixture of compound (3) (40 g, 124 mmol), 5 mass% Pd/C (50% water-containing type), premium egret activated carbon (4.0 g), and dioxane (400 g) was subjected to hydrogen pressure at 80° C. was stirred for 8 hours. After completion of the reaction, the catalyst was filtered, then concentrated, 2-propanol (400 g) was added, and the mixture was stirred at 5°C for 1 hour. The precipitated crystals were filtered under reduced pressure, washed with 2-propanol (100 g), and dried to obtain powder crystals (4) (amount 17 g, yield 52%).

[Formula 39]

Compound (4) (27.4 g, 104 mmol) and THF (270 g) were poured into a 1 L four-necked flask, and trifluoroacetic anhydride (46.5 g, 220 mmol) was added dropwise under ice-cooling, 1 hour stirred. After confirming the completion of the reaction by HPLC (high-performance liquid chromatography), the mixture was concentrated to dryness. To the obtained solid, THF (600 g) and potassium carbonate (45.1 g, 326 mmol) were added, and methyl iodide (45.8 g, 324 mmol) was added dropwise at room temperature, followed by stirring at 40°C for 22 hours. After confirming the completion of the reaction by HPLC (high-performance liquid chromatography), the salt was removed by filtration under reduced pressure and concentrated to dryness.

N-methylpyrrolidone (200g), pure water (30g), and potassium hydroxide (20.8g, 315 mmol) were added to the obtained solid, and it stirred at 60 degreeC for 30 minutes. After confirming completion of the reaction by HPLC (high-performance liquid chromatography), the reaction liquid was added to cold water (1200 g) and stirred for 1 hour. The precipitated crystals were filtered under reduced pressure, washed with 2-propanol (100 g), and then dried to obtain powder crystals (5) (amount 22.9 g, yield 76%).

[Formula 40]

Sodium hydride (19.7 g, 494 mmol) and N-methylpyrrolidone (20 g) were added to a 1-L four neck flask, and it ice-cooled. On the other hand, a solution of compound (5) (22.9 g, 78.7 mmol) and N-methylpyrrolidone (115 g) was slowly added dropwise under a nitrogen flow, followed by 4-fluoronitrobenzene (44.4 g) , 315 mmol) and a solution of N-methylpyrrolidone (44 g) were added dropwise, followed by stirring at room temperature for 24 hours.

After confirming completion of the reaction by HPLC (high-performance liquid chromatography), the reaction liquid was added to cold water (1800 g) and stirred for 1 hour. The obtained crude crystals were repulp-washed with tetrahydrofuran (450 g), filtered under reduced pressure, washed with methanol (100 g), and dried to obtain powdery crystals (6) (amount 22.7 g, yield 54%). .

[Formula 41]

A mixture of compound (6) (22.7 g, 42.6 mmol), 5 mass% Pd/C (50% water-containing type), characteristic egret activated carbon (2.0 g), and dioxane (230 g) was subjected to hydrogen pressure at 80° C. was stirred for 8 hours. After completion of the reaction, the catalyst was filtered, then concentrated, 2-propanol (300 g) was added, and the mixture was stirred at 5°C for 1 hour. The precipitated crystals were filtered under reduced pressure, washed with 2-propanol (100 g), and then dried to obtain powdered crystals (DA-1) (amount 17.4 g, yield 86%).

[Synthesis Example 1]

After adding DA-1 (1.99 g, 4.2 mmol) to a 100 ml four-neck flask equipped with a stirring device and a nitrogen introduction tube, 20.0 g of a mixed solvent of NMP:GBL = 1:1 (mass ratio) It was added and stirred while sending nitrogen to dissolve. While stirring this solution, CA-1 (0.61 g, 2.8 mmol), CA-2 (0.73 g, 3.7 mmol), and 8.0 g of a mixed solvent of NMP:GBL = 1:1 were added, followed by an additional 50 The polyamic-acid solution (PAA-A1) was obtained by stirring at degreeC for 12 hours.

[Synthesis Examples 2 to 6]

Polyamic acid solution (PAA-A2) and polyamic acid solution (PAA-B1) - ( PAA-B4) was obtained.

[Synthesis Example 7]

DA-6 (4.03 g, 16.5 mmol), DA-7 (3.59 g, 9.0 mmol), and DA-8 (2.51 g, After adding 4.5 mmol), NMP74.0g was added, and it stirred, sending nitrogen, and it was made to melt|dissolve. 9.0 g of CA-4 (4.37 g, 19.5 mmol) and NMP were added, stirring this solution, and it stirred under 40 degreeC conditions for 3 hours. Then, after adding CA-2 (1.71 g, 8.7 mmol) and 9.0 g of NMP on 25 degreeC conditions, the polyamic-acid solution was obtained by stirring further for 12 hours.

After fractionating 80.0g of this polyamic-acid solution and adding 20.0g of NMP, 6.8g of acetic anhydride and 1.8g of pyridines were added, and it was made to react at 50 degreeC for 3 hours. This reaction solution was injected|thrown-in to 434.4 g of methanol with stirring, and the precipitated deposit was separated by filtration. Methanol wash|cleaned this deposit, it dried under reduced pressure at 60 degreeC, and the powder of polyimide was obtained. The imidation ratio of this polyimide was 75 %. The polyimide solution (SPI-B5) was obtained by adding NMP80.0g to 20.0g of obtained polyimide powders, stirring at 70 degreeC for 20 hr, and making it melt|dissolve.

[Synthesis Example 8]

DA-5 (68.5 g, 280 mmol) and DA-8 (23.9 g, 70 mmol) were weighed into a 1000 ml four-necked flask equipped with a stirring device and a nitrogen inlet tube, and NMP was 586 g was added and stirred while sending nitrogen to dissolve. CA-4 (74.5 g, 332 mmol) was added, stirring this solution, NMP was further added so that solid content concentration might be 18 mass %, it stirred at room temperature for 24 hours, and the polyamic-acid solution was obtained.

200g of this polyamic-acid solution was measured, 100g of NMPs were added, and it stirred for 30 minutes. 21.78 g of acetic anhydride and 2.81 g of pyridines were added to the obtained polyamic-acid solution, and it was made to react at 60 degreeC for 3 hours. The obtained reaction liquid was injected|thrown-in to 624.2 g of methanol, stirring, and the precipitated deposit was separated by filtration. Methanol wash|cleaned this deposit, it dried under reduced pressure at 60 degreeC, and the powder of polyimide was obtained. The imidation ratio of this polyimide was 68 %. The polyimide solution (SPI-B6) was obtained by adding NMP239.8g to 32.7g of obtained polyimide powders, stirring at 70 degreeC for 20 hours, and making it melt|dissolve.

[Examples 1 to 12] and [Comparative Examples 1 to 7]

A solvent and an additive are added, stirring the polyamic acid solution obtained by the synthesis examples 1-6, and the polyimide solution obtained by the synthesis examples 7 and 8 so that it may become a composition shown in Table 2 and Table 3, respectively, and it is room temperature The liquid crystal aligning agent of Examples 1-12 and Comparative Examples 1-7 was obtained by stirring for 2 hours.

In addition, in Tables 2 and 3, *1, *2 shows the content (addition) amount (mass part) with respect to 100 mass parts of all polymers, *3 of the solvent with respect to 100 mass parts of liquid crystal aligning agents The usage amount (parts by mass) is shown.

<Production of liquid crystal display element by rubbing method>

A glass substrate with an electrode having a thickness of 0.7 mm was prepared in a size of 30 mm in length × 35 mm in width. On the board|substrate, the IZO electrode provided with the beta phase pattern which comprises a counter electrode as a 1st layer is formed. On the counter electrode of the first layer, as the second layer, a SiN (silicon nitride) film formed by the CVD method is formed. The film thickness of the SiN film of the second layer is 500 nm, and functions as an interlayer insulating film. On the SiN film of the 2nd layer, the comb-tooth-shaped pixel electrode formed by patterning the IZO film as a 3rd layer is arrange|positioned, and two pixels of a 1st pixel and a 2nd pixel are formed. The size of each pixel is 10 mm long and about 5 mm wide. At this time, the counter electrode of the first layer and the pixel electrode of the third layer are electrically insulated by the action of the SiN film of the second layer.

The pixel electrode of the 3rd layer has a comb-tooth-shaped shape comprised by arranging a plurality of electrode elements in the shape of "<<" in which the central part is bent (refer FIG. 3 of Unexamined-Japanese-Patent No. 2014-77845). The width in the width direction of each electrode element is 3 µm, and the distance between the electrode elements is 6 µm. Since the pixel electrode forming each pixel is constituted by arranging a plurality of electrode elements in the shape of "a" in which the central part is bent, the shape of each pixel is not a rectangular shape, but in the central part similarly to the electrode element. It is curved and has a shape similar to the "letter of "" in bold. And each pixel is divided|segmented up and down with the bent part in the center as a boundary, and has a 1st area|region above a bending part, and a 2nd area|region below.

Comparing the 1st area|region and 2nd area|region of each pixel, the formation direction of the electrode element of the pixel electrode which comprises them differs. That is, based on the rubbing direction of the liquid crystal alignment layer to be described later, the electrode element of the pixel electrode is formed to form an angle of +10° (clockwise) in the first region of the pixel, and the electrode of the pixel electrode in the second region of the pixel The elements are formed to form an angle of -10° (counterclockwise). In addition, in the first region and the second region of each pixel, the directions of the rotational operation (in-plane switching) in the substrate plane of the liquid crystal caused by the voltage application between the pixel electrode and the counter electrode are opposite to each other. is structured to be

Next, after filtering the liquid crystal aligning agent with a filter having a pore diameter of 1.0 µm, an ITO film is formed on the back surface as the substrate on which the electrode is formed and as a counter substrate, and each of the glass substrates having a columnar spacer with a height of 4 µm was spin-coated. Then, after drying for 5 minutes on an 80 degreeC hotplate, it baked at 230 degreeC for 20 minutes, and obtained the polyimide film with a film thickness of 60 nm on each board|substrate. After rubbing the polyimide film surface with a rayon cloth under the conditions of a roll diameter of 120 mm, the number of roller rotations of 500 rpm, a stage movement speed of 30 mm/sec, and a rubbing pressure of 0.3 mm, ultrasonic wave in pure water for 1 minute It irradiated and dried at 80 degreeC for 10 minutes.

Using the two types of substrates on which the liquid crystal aligning film was formed, the respective rubbing directions were combined so as to be antiparallel, and the liquid crystal injection port was left and the periphery was sealed to prepare an empty cell having a cell gap of 3.8 µm. After vacuum-injecting a liquid crystal (Merck Corporation make, MLC-3019) into this empty cell at room temperature, the injection port was sealed and it was set as the liquid crystal cell of antiparallel orientation. The obtained liquid crystal cell comprises an FFS mode liquid crystal display element. Then, after heating a liquid crystal cell at 120 degreeC for 1 hour and leaving it to stand overnight, it was used for evaluation.

<Evaluation of afterimage erasing time>

The prepared liquid crystal cell was installed between two polarizing plates arranged so that the polarization axes were orthogonal to each other, the LED backlight was turned on in a state where no voltage was applied, and the arrangement angle of the liquid crystal cell was adjusted so that the luminance of the transmitted light was the smallest. Next, the V-T curve (voltage-transmittance curve) was measured, applying the alternating voltage with a frequency of 30 Hz to this liquid crystal cell, and relative transmittance computed the alternating voltage used as 23 % as a drive voltage.

In residual image evaluation, a 1V DC voltage was simultaneously applied and it was made to drive for 30 minutes, applying the alternating voltage of the frequency 30Hz used as 23 % and driving a liquid crystal cell in a relative transmittance|permeability. Thereafter, the applied DC voltage value was set to 0 V, only the application of the DC voltage was stopped, and the driving was performed in that state for an additional 15 minutes.

Residual image evaluation digitized the time when the relative transmittance fell to 30% or less from the time when application of a DC voltage was started until 30 minutes passed. When the relative transmittance fell to 30% or less within 5 minutes, it was evaluated as "○", and when it was within 6 to 30 minutes, it was evaluated as "Δ". When 30 minutes or more were needed until the relative transmittance|permeability fell to 30 % or less, it was set as the afterimage erasure|elimination impossibility, and evaluated as "x". And the residual image evaluation by the method mentioned above was performed on temperature conditions whose temperature of a liquid crystal cell is a state of 23 degreeC.

<Evaluation of the flicker shift that occurs immediately after starting the drive>

The prepared liquid crystal cell was installed between two polarizing plates arranged so that the polarization axes were orthogonal to each other, the LED backlight was turned on in a state where no voltage was applied, and the arrangement angle of the liquid crystal cell was adjusted so that the luminance of the transmitted light was the smallest. Next, the V-T curve (voltage-transmittance curve) was measured, applying the alternating voltage with a frequency of 30 Hz to this liquid crystal cell, and relative transmittance computed the alternating voltage used as 23 % as a drive voltage.

In the measurement of the flicker level, the LED backlight that has been turned on is temporarily turned off and left to block for 72 hours, then the LED backlight is turned on again, and an AC voltage with a frequency of 30 Hz at which the relative transmittance becomes 23% is applied at the same time as the backlight lighting starts. , the liquid crystal cell was driven for 60 min to track the flicker amplitude. The flicker amplitude was read with a data acquisition/data logger switch unit 34970A (manufactured by Agilent Technologies) connected through a photodiode and an I-V conversion amplifier to the transmitted light of the LED backlight passing through the two polarizing plates and the liquid crystal cell between them. The flicker level was calculated by the following equation.

Flicker level (%) = {flicker amplitude/(2 × z)} × 100

In the above formula, z is a value read by the data acquisition/data logger switch unit 34970A for the luminance when driving with an AC voltage having a frequency of 30 Hz at which the relative transmittance is 23%.

Evaluation of the flicker level was evaluated by defining "○" when the flicker level was maintained at less than 3% until 60 minutes passed from when the LED backlight was turned on and application of the AC voltage was started. . When the flicker level reached 3% or more for 60 minutes, it was defined as "x" and evaluated.

Evaluation of the flicker level by the method mentioned above was performed on the temperature condition of the state whose temperature of a liquid crystal cell is 23 degreeC.

<Evaluation result>

About the liquid crystal display element using each liquid crystal aligning agent of said Example 1, 2, 4, 5 and Comparative Examples 1-4, 6, 7, the flicker shift which generate|occur|produces immediately after the afterimage erasing time implemented above and drive start Tables 4 to 6 show the evaluation results.

In addition, in Tables 4-6, *1 shows content (mass part) of each polymer with respect to 100 mass parts of all polymers.

As Tables 4-6 show, the liquid crystal display element using the liquid crystal aligning agent of Examples 1, 2, 4, 5 is quick in relaxation|moderation of an accumulation|storage electric charge, and the flicker shift which generate|occur|produces immediately after a drive start It turns out that it doesn't happen very well.

<Preparation of the liquid crystal display element by the photo-alignment method>

After filtering the liquid crystal aligning agent with a filter having a pore diameter of 1.0 μm, an ITO film is formed on the back surface as the prepared substrate on which the electrode is formed and a counter substrate, and spins on each of the glass substrates having columnar spacers with a height of 4 μm Coated. Subsequently, after drying for 5 minutes on an 80 degreeC hotplate, it baked at 230 degreeC for 30 minute(s), and obtained the polyimide film on each board|substrate as a 100-nm-thick coating film. This coating film surface was irradiated with 250 mJ/cm 2 of ultraviolet rays having a wavelength of 254 nm linearly polarized with an extinction ratio of 26:1 through a polarizing plate.

After making this board|substrate immersed in 25 degreeC EL (ethyl lactate) solution for 5 minutes, and then immersed in 25 degreeC pure water for 1 minute, it heated on a 230 degreeC hotplate for 30 minutes, and obtained the board|substrate with a liquid crystal aligning film. The above two boards are set as one set, a sealing compound is printed on the board, and the other board is bonded so that the liquid crystal aligning film surface is facing and the orientation direction is 0°, and then the sealing agent is cured and the blank cells were fabricated. MLC-7026-100 (made by Merck Corporation) of a negative liquid crystal was inject|poured into this empty cell by the reduced pressure injection method, the injection port was sealed, and the FFS drive liquid crystal cell was obtained. Then, after heating the obtained liquid crystal cell at 110 degreeC for 1 hour and leaving it to stand overnight, it was used for each evaluation.

<Evaluation of afterimage erasing time>

It carried out similarly to the case of the liquid crystal display element by a rubbing method, and evaluated the residual image using the optical system of the liquid crystal display element by the photo-alignment method produced above.

<Evaluation of the flicker level immediately after operation>

It carried out similarly to the case of the liquid crystal display element by a rubbing method, and evaluated the residual image using the optical system of the liquid crystal display element by the photo-alignment method produced above.

<Evaluation result>

About the liquid crystal display element using the liquid crystal aligning agent obtained by the said Example 12 and the comparative example 7, Table 7 shows the result of evaluation of the afterimage erasure|elimination time implemented above, and evaluation of the flicker level immediately after a drive. In addition, in Table 7, *1 shows content (mass part) of each polymer with respect to 100 mass parts of all polymers.

As Table 7 shows, in the liquid crystal display element using the liquid crystal aligning agent of Example 12, relaxation|moderation of an accumulation|storage electric charge is quick, and it turns out that the flicker shift which generate|occur|produces immediately after a drive start does not generate|occur|produce easily.

Industrial Applicability

The liquid crystal aligning agent using the novel polymer of this invention is widely used for liquid crystal display elements of vertical electric field systems, such as a TN system and a VA system, especially transverse electric field systems, such as an IPS system and an FFS system.

In addition, the specification of Japanese Patent Application No. 2016-191765 for which it applied on September 29, 2016, a claim, drawing, and the abstract are referred here, and it takes in as an indication of the specification of this invention.

Claims (15)

The polymer obtained from diamine which has a structure shown by following formula (1), and organic solvent are contained, The liquid crystal aligning agent characterized by the above-mentioned.

(In formula (1), R ¹ and R ² are a hydrogen atom or a monovalent organic group. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group. * represents a bonding site.) The method of claim 1,
The polymer is at least one polymer selected from the group consisting of a polyimide precursor which is a polycondensate of a diamine having a structure represented by the formula (1) and tetracarboxylic dianhydride, and a polyimide that is an imidized product thereof, liquid crystal aligning agent. The method of claim 1,
The liquid crystal aligning agent in which the said diamine is represented by the following formula (2).

(In formula (2), the definitions of R ¹ and R ² are the same as those of the formula (1) above, each of R ³ independently represents a single bond or a structure of the following formula (3), and n is 1 to 3 represents an integer of. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group.)

(in formula (3), R ⁴ is a single bond, -O-, -COO-, -OCO-, -(CH ₂ ) _l -, -O(CH ₂ ) _m O-, -CONH-, and - represents a divalent organic group selected from NHCO- (l, m represents an integer of 1 to 5), * ₁ represents a site bonding to the benzene ring in formula (2), * ₂ represents an amino group in formula (2) indicates the site where it binds.) 3. The method of claim 2,
The liquid crystal aligning agent in which the said polyimide precursor has a structure represented by following formula (4).

(In the formula (4), X ₁ is a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ₁ is a divalent organic group derived from the diamine represented by the formula (1), and R ₅ is a hydrogen atom or It is an alkyl group having 1 to 5 carbon atoms.) 5. The method of claim 4,
The liquid crystal aligning agent whose X< ₁ > is at least 1 sort(s) chosen from the group which consists of a structure of following (A-1) - (A-21) in said Formula (4).

5. The method of claim 4,
The liquid crystal aligning agent in which the polymer which has a structural unit represented by said Formula (4) contains 10 mol% or more with respect to all the polymers contained in a liquid crystal aligning agent. The method of claim 1,
The liquid crystal aligning agent in which the said organic solvent contains at least 1 sort(s) chosen from the group which consists of 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether. The liquid crystal aligning film obtained using the liquid crystal aligning agent in any one of Claims 1-7. A liquid crystal display element provided with the liquid crystal aligning film of Claim 8. 10. The method of claim 9,
A liquid crystal display element in which the liquid crystal display element is a transverse electric field driving method. The at least 1 sort(s) of polymer chosen from the group which consists of a polyimide precursor which is a polycondensate of the diamine which has a structure shown by following formula (1), and tetracarboxylic dianhydride, and the polyimide which is its imidated product.

(In formula (1), R ¹ and R ² are a hydrogen atom or a monovalent organic group. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group. * represents a bonding site.) 12. The method of claim 11,
The polymer in which the said diamine is represented by the following formula (2).

(In formula (2), the definitions of R ¹ and R ² are the same as those of the formula (1) above, each of R ³ independently represents a single bond or a structure of the following formula (3), and n is 1 to 3 represents an integer of. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group.)

(in formula (3), R ⁴ is a single bond, -O-, -COO-, -OCO-, -(CH ₂ ) _l -, -O(CH ₂ ) _m O-, -CONH-, and - represents a divalent organic group selected from NHCO- (l, m represents an integer of 1 to 5), * ₁ represents a site bonding to the benzene ring in formula (2), * ₂ represents an amino group in formula (2) indicates the site where it binds.) 13. The method according to claim 11 or 12,
The polymer in which the said polyimide precursor is represented by following formula (4).

(In the formula (4), X ₁ is a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ₁ is a divalent organic group derived from the diamine represented by the formula (1), and R ₅ is a hydrogen atom or It is an alkyl group having 1 to 5 carbon atoms.) 14. The method of claim 13,
In the formula (4), X ₁ is at least one polymer selected from the group consisting of structures represented by the following (A-1) to (A-21).

Diamine represented by the following formula (2).

(In formula (2), the definitions of R ¹ and R ² are the same as those of the formula (1) above, each of R ³ independently represents a single bond or a structure of the following formula (3), and n is 1 to 3 represents an integer of. Any hydrogen atom in the benzene ring may be substituted with a monovalent organic group.)

(in formula (3), R ⁴ is a single bond, -O-, -COO-, -OCO-, -(CH ₂ ) _l -, -O(CH ₂ ) _m O-, -CONH-, and - represents a divalent organic group selected from NHCO- (l, m represents an integer of 1 to 5), * ₁ represents a site bonding to the benzene ring in formula (2), * ₂ represents an amino group in formula (2) indicates the site where it binds.)